7040

TGFB1

transforming growth factor, beta 1;TGFB1;transforming growth factor, beta 1

TGF-beta-1|latency-associated peptide|prepro-transforming growth factor beta-1|transforming growth factor beta-1

19q13.1

protein-coding

We have shown recently that the hyaluronan receptor, CD44, and matrix metalloproteinase 9 (MMP-9) form a complex on the surface of TA/St mouse mammary carcinoma cells that activates latent transforming growth factor-beta (TGF-beta) and is required for tumor invasion. Disruption of the CD44/MMP-9 complex by expression of soluble CD44 results in the loss of tumor invasiveness and abrogates tumor cell survival in host lung parenchyma following intravenous injection into syngeneic mice. To explore the molecular nature of the survival signals derived from the CD44/MMP-9 complex during the development of tumor metastasis, we investigated the possibility that activation of latent TGF-beta by the CD44/MMP-9 complex is responsible for tumor cell survival in host lung parenchyma. TA3 cells overexpressing dominant negative soluble CD44 (TA3sCD44), which compromises native CD44 function and the ability of TA3 cells to develop metastases, were transfected with constitutively active or latent TGF-beta2 and tested for their ability to form tumors in syngeneic mice. Our results demonstrate that expression of the constitutively active, but not the latent, form of TGF-beta2 rescues TA3sCD44 cells from apoptosis during lung colonization. These observations provide evidence that activation of latent TGF-beta constitutes an event downstream of CD44-dependent signals that is required for tumor cell survival and metastatic colony formation. The functional axis composed of CD44, MMP-9 and TGF-beta may therefore play an important role in the metastatic proclivity of selected tumor types.

During breast cancer progression, transforming growth factor-beta (TGF-beta) switches from a tumor suppressor to a pro-metastatic molecule. Several recent studies suggest that this conversion in TGF-beta function depends upon fundamental changes in the TGF-beta signaling system. We show here that these changes in TGF-beta signaling are concomitant with aberrant expression of the focal adhesion protein, p130Cas. Indeed, elevating expression of either the full-length (FL) or just the carboxyl terminus (CT) of p130Cas in mammary epithelial cells (MECs) diminished the ability of TGF-beta1 to activate Smad2/3, but increased its coupling to p38 MAPK. This shift in TGF-beta signaling evoked (i) resistance to TGF-beta-induced growth arrest, and (ii) acinar filling upon three-dimensional organotypic cultures of p130Cas-FL or -CT expressing MECs. Furthermore, rendering metastatic MECs deficient in p130Cas enhanced TGF-beta-stimulated Smad2/3 activity, which restored TGF-beta-induced growth inhibition both in vitro and in mammary tumors produced in mice. Additionally, whereas elevating TbetaR-II expression in metastatic MECs had no affect on their phosphorylation of Smad2/3, this event markedly enhanced their activation of p38 MAPK, leading to increased MEC invasion and metastasis. Importantly, depleting p130Cas expression in TbetaR-II-expressing metastatic MECs significantly increased their activation of Smad2/3, which (i) reestablished the physiologic balance between canonical and noncanonical TGF-beta signaling, and (ii) reversed cellular invasion and early mammary tumor cell dissemination stimulated by TGF-beta. Collectively, our findings identify p130Cas as a molecular rheostat that regulates the delicate balance between canonical and noncanonical TGF-beta signaling, a balance that is critical to maintaining the tumor suppressor function of TGF-beta during breast cancer progression.

The E3 ubiquitin ligase human murine double minute (HDM2) is overexpressed in 40%-80% of late-stage metastatic cancers in the absence of gene amplification. Hdm2 regulates p53 stability via ubiquitination and has also been implicated in altering the sensitivity of cells to TGF-beta1. Whether TGF-beta1 signaling induces Hdm2 expression leading to HDM2-mediated destabilization of p53 has not been investigated. In this study, we report that TGF-beta1-activated SMA- and MAD3 (Smad3/4) transcription factors specifically bound to the second promoter region of HDM2, leading to increased HDM2 protein expression and destabilization of p53 in human cancer cell lines. Additionally, TGF-beta1 expression led to Smad3 activation and murine double minute 2 (Mdm2) expression in murine mammary epithelial cells during epithelial-to-mesenchymal transition (EMT). Furthermore, histological analyses of human breast cancer samples demonstrated that approximately 65% of late-stage carcinomas were positive for activated Smad3 and HDM2, indicating a strong correlation between TGF-beta1-mediated induction of HDM2 and late-stage tumor progression. Identification of Hdm2 as a downstream target of TGF-beta1 represents a critical prosurvival mechanism in cancer progression and provides another point for therapeutic intervention in late-stage cancer.

OBJECTIVE: To investigate the expression of MMP-2, TIMP-2, TGF-beta1 and TGF-betaRI and the relationship among them in breast cancer. METHODS: The protein expression of MMP-2, TIMP-2, TGF-beta1 and TGF-betaRI was detected on tissue chips by S-P immunohistochemical staining in 160 cases of breast carcinoma. RESULTS: The positive rates of TGF-beta1, TGF-beta1 mRNA, MMP-2, MMP-9, TIMP-1 and TIMP-2 expression were 73.7%, 56.2%, 96.9%, 95.0%, 87.5% and 89.4%, respectively. Axillary lymph node metastasis and TNM staging (P < 0.01 and P < 0.01, respectively) were positively correlated to the expression of TGF-beta1. Relase-free survival of TGF-beta1 positive group was lower than that of TGF-beta1 negative group (P = 0.023). The expression of MMP-2 or MMP-9 was positively correlated to that of TGF-beta1 (r = 0.170, P < 0.05; r = 0.221, P < 0.01) and was negatively correlated to that of TGF-beta1 mRNA (r = -0.126, P > 0.05;r = 0.019, P > 0.05). CONCLUSION: The expression of TGF-beta1 may be closely correlated with the invasion and metastasis of breast cancer. TGF-beta1-induced invasiveness and metastasis of breast cancer cells are mediated by MMP-2 and MMP-9.

Annexin A1 (AnxA1) is a candidate regulator of the epithelial- to mesenchymal (EMT)-like phenotypic switch, a pivotal event in breast cancer progression. We show here that AnxA1 expression is associated with a highly invasive basal-like breast cancer subtype both in a panel of human breast cancer cell lines as in breast cancer patients and that AnxA1 is functionally related to breast cancer progression. AnxA1 knockdown in invasive basal-like breast cancer cells reduced the number of spontaneous lung metastasis, whereas additional expression of AnxA1 enhanced metastatic spread. AnxA1 promotes metastasis formation by enhancing TGFbeta/Smad signaling and actin reorganization, which facilitates an EMT-like switch, thereby allowing efficient cell migration and invasion of metastatic breast cancer cells.

Carcinoma are complex societies of mutually interacting cells in which there is a progressive failure of normal homeostatic mechanisms, causing the parenchymal component to expand inappropriately and ultimately to disseminate to distant sites. When a cancer cell metastasizes, it first will be exposed to cancer associated fibroblasts in the immediate tumor microenvironment and then to normal fibroblasts as it traverses the underlying connective tissue towards the bloodstream. The interaction of tumor cells with stromal fibroblasts influences tumor biology by mechanisms that are not yet fully understood. Here, we report a role for normal stroma fibroblasts in the progression of invasive tumors to metastatic tumors. Using a coculture system of human metastatic breast cancer cells (MCF10CA1a) and normal murine dermal fibroblasts, we found that medium conditioned by cocultures of the two cell types (CoCM) increased migration and scattering of MCF10CA1a cells in vitro, whereas medium conditioned by homotypic cultures had little effect. Transient treatment of MCF10CA1a cells with CoCM in vitro accelerated tumor growth at orthotopic sites in vivo, and resulted in an expanded pattern of metastatic engraftment. The effects of CoCM on MCF10CA1a cells were dependent on small amounts of active TGF-beta1 secreted by fibroblasts under the influence of the tumor cells, and required intact ALK5-, p38-, and JNK signaling in the tumor cells. In conclusion, these results demonstrate that transient interactions between tumor cells and normal fibroblasts can modify the acellular component of the local microenvironment such that it induces long-lasting increases in tumorigenicity and alters the metastatic pattern of the cancer cells in vivo. TGF-beta appears to be a key player in this process, providing further rationale for the development of anti-cancer therapeutics that target the TGF-beta pathway.

OBJECTIVE: To use cytoplasmic tissue extract as a new specimen source to quantify transforming growth factor beta 1 (TGFbeta1) protein in metastatic axillary lymph node tissue (ALNT) of breast cancer (BC) patients and to confirm the feasibility of this approach in a prospective pilot study on a subgroup of patients with invasive BC. STUDY DESIGN: The 6 selected malignant and autologous nonmalignant pairs of ALNT were fractionated, under special preanalytical, nonaggressive/nondenaturing conditions, to obtain respective cytoplasmic extracts for TGFbeta1 detection by the Quantikine (R&D Systems Inc., Minneapolis, Minnesota, U.S.A.) enzyme-linked immunosorbent assay kit. RESULTS: The data indicated a highly significant (r = 0.973054) positive linear correlation between the TGFbeta1 concentration and total protein concentration in cytoplasmic extract of metastatic ALNT. The subsequent patients' pilot study, performed strictly before any clinicopathologic factors were accessible, revealed significantly (p < 0.01) elevated TGFbeta1 in malignant ALNT (median value: 1.05 ng/mg protein, range: 0.67-3.6 ng/mg protein, n = 6) vs. autologous nonmalignant ALNT controls (median value: 0.48 ng/mg protein, range: 0.29-0.90 ng/mg protein, n = 6). This elevation was correlated with the number of metastatic axillary lymph nodes with respect to the total and was consistent with an increase in size of tumor deposits in axillary lymph nodes. CONCLUSION: Our data provide for the first time suggestive evidence that the TGFbeta1 level in cytoplasmic extracts of metastatic ALNTs may be a promising biomarker of invasiveness for BC patients. Confirmatory, large-scale studies are needed to evaluate possible implications of this putative biomarker in BC diagnosis and treatment.

metastasis is a complex process facilitated by the action of several genes. metastasis associated 1 (MTA1) gene is one such gene which assists the process of metastasis by regulating several molecular targets. MTA1 acts as part of a nucleosome remodelling and histone deacetylation complex, which is involved in transcriptional regulation. expression of MTA1 has been shown to be closely correlated with aggressiveness in several types of cancers, including breast cancer. In the present study we show that MTA1 regulates SMAD7, a component of Transforming growth factor beta (TGFbeta) signalling. TGFbeta signals are transduced to the nucleus by the Smad family of proteins, which includes Smad7, an inhibitory SMAD, which acts as a negative regulator of TGFbeta. On knockdown of MTA1, SMAD7 expression increases. Treating cells with a histone deacetylase inhibitor also increases SMAD7 expression. MTA1 is recruited to SMAD7 promoter region. SMAD7 inhibits activation of SMAD2 and SMAD3 and we show that the levels of these active SMAD proteins are decreased in cells expressing shRNA against MTA1. We further show that on MTA1 knockdown, the expression of downstream targets of SMAD7 is decreased. MTA1 thus appears to regulate a key inhibitor of TGFbeta signalling, SMAD7. By regulating molecules like SMAD7 MTA1 might assist the process of tumourigenesis and metastasis.

Although the role of TGF-beta in tumor progression has been studied extensively, its impact on drug delivery in tumors remains far from understood. In this study, we examined the effect of TGF-beta blockade on the delivery and efficacy of conventional therapeutics and nanotherapeutics in orthotopic mammary carcinoma mouse models. We used both genetic (overexpression of sTbetaRII, a soluble TGF-beta type II receptor) and pharmacologic (1D11, a TGF-beta neutralizing antibody) approaches to block TGF-beta signaling. In two orthotopic mammary carcinoma models (human MDA-MB-231 and murine 4T1 cell lines), TGF-beta blockade significantly decreased tumor growth and metastasis. TGF-beta blockade also increased the recruitment and incorporation of perivascular cells into tumor blood vessels and increased the fraction of perfused vessels. Moreover, TGF-beta blockade normalized the tumor interstitial matrix by decreasing collagen I content. As a result of this vessel and interstitial matrix normalization, TGF-beta blockade improved the intratumoral penetration of both a low-molecular-weight conventional chemotherapeutic drug and a nanotherapeutic agent, leading to better control of tumor growth.

The ErbB2 and TGFbeta signaling pathways cooperate to promote the migratory, invasive, and metastatic behavior of breast cancer cells. We previously demonstrated that ShcA is necessary for these synergistic interactions. Through a structure/function approach, we now show that the phosphotyrosine-binding, but not the Src homology 2, domain of ShcA is required for TGFbeta-induced migration and invasion of ErbB2-expressing breast cancer cells. We further demonstrate that the tyrosine phosphorylation sites within ShcA (Tyr(239)/Tyr(240) and Tyr(313)) transduce distinct and non-redundant signals that promote these TGFbeta-mediated effects. We demonstrate that Grb2 is required specifically downstream of Tyr(313), whereas the Tyr(239)/Tyr(240) phosphorylation sites require the Crk adaptor proteins to augment TGFbeta-induced migration and invasion. Furthermore, ShcA Tyr(313) phosphorylation enhances tumor cell survival, and ShcA Tyr(239)/Tyr(240) signaling promotes endothelial cell recruitment into ErbB2-expressing breast tumors in vivo, whereas all three ShcA tyrosine residues are required for efficient breast cancer metastasis to the lungs. Our data uncover a novel ShcA-dependent signaling axis downstream of TGFbeta and ErbB2 that requires both the Grb2 and Crk adaptor proteins to increase the migratory and invasive properties of breast cancer cells. In addition, signaling downstream of specific ShcA tyrosine residues facilitates the survival, vascularization, and metastatic spread of breast tumors.

A key feature of TGF-beta signaling activation in cancer cells is the sustained activation of SMAD complexes in the nucleus; however, the drivers of SMAD activation are poorly defined. Here, using human and mouse breast cancer cell lines, we found that oncogene forkhead box M1 (FOXM1) interacts with SMAD3 to sustain activation of the SMAD3/SMAD4 complex in the nucleus. FOXM1 prevented the E3 ubiquitin-protein ligase transcriptional intermediary factor 1 gamma (TIF1gamma) from binding SMAD3 and monoubiquitinating SMAD4, which stabilized the SMAD3/SMAD4 complex. Loss of FOXM1 abolished TGF-beta-induced SMAD3/SMAD4 formation. Moreover, the interaction of FOXM1 and SMAD3 promoted TGF-beta/SMAD3-mediated transcriptional activity and target gene expression. We found that FOXM1/SMAD3 interaction was required for TGF-beta-induced breast cancer invasion, which was the result of SMAD3/SMAD4-dependent upregulation of the transcription factor SLUG. Importantly, the function of FOXM1 in TGF-beta-induced invasion was not dependent on FOXM1's transcriptional activity. Knockdown of SMAD3 diminished FOXM1-induced metastasis. Furthermore, FOXM1 levels correlated with activated TGF-beta signaling and metastasis in human breast cancer specimens. Together, our data indicate that FOXM1 promotes breast cancer metastasis by increasing nuclear retention of SMAD3 and identify crosstalk between FOXM1 and TGF-beta/SMAD3 pathways. This study highlights the critical interaction of FOXM1 and SMAD3 for controlling TGF-beta signaling during metastasis.

Breast cancer (BC) is potentially life-threatening malignancy that still causes high mortality among women. Scientific research in this field is focused on deeper understanding of pathogenesis and progressing of BC, in order to develop relevant diagnosis and improve therapeutic treatment. Multifunctional cytokine TGF- beta 1 is one of many factors that have a direct influence on BC pathophysiology. expression of TGF- beta 1, induction of canonical and noncanonical signaling pathways, and mutations in genes encoding TGF- beta 1 and its receptors are correlated with oncogenic activity of this cytokine. In early stages of BC this cytokine inhibits epithelial cell cycle progression and promotes apoptosis, showing tumor suppressive effects. However, in late stages, TGF- beta 1 is linked with increased tumor progression, higher cell motility, cancer invasiveness, and metastasis. It is also involved in cancer microenvironment modification and promotion of epithelial to mesenchymal transition (EMT). This review summarizes the current knowledge on the phenomenon called "TGF- beta 1 paradox", showing that better understanding of TGF- beta 1 functions can be a step towards development of new therapeutic approaches. According to current knowledge several drugs against TGF- beta 1 have been developed and are either in nonclinical or in early stages of clinical investigation.

TGFbeta signaling is known to drive metastasis in human cancer. Under physiologic conditions, the level of TGFbeta activity is tightly controlled by a regulatory network involving multiple negative regulators. At metastasis, however, these inhibitory mechanisms are usually overridden so that oncogenic TGFbeta signaling can be overactivated and sustained. To better understand how the TGFbeta inhibitors are suppressed in metastatic breast cancer cells, we compared miRNA expression profiles between breast cancers with or without metastasis and found that the miR424-503 cluster was markedly overexpressed in metastatic breast cancer. Mechanistic studies revealed that miR424 and miR503 simultaneously suppressed Smad7 and Smurf2, two key inhibitory factors of TGFbeta signaling, leading to enhanced TGFbeta signaling and metastatic capability of breast cancer cells. Moreover, antagonizing miR424-503 in breast cancer cells suppressed metastasis in vivo and increased overall host survival. Interestingly, our study also found that heterogeneous expression of the miR424-503 cluster contributed to the heterogeneity of TGFbeta activity levels in, and metastatic potential of, breast cancer cell subsets. Overall, our findings demonstrate a novel mechanism, mediated by elevated expression of the miR424-503 cluster, underlying TGFbeta activation and metastasis of human breast cancer.

PURPOSE: Presence of pelvic lymph node metastases is the main prognostic factor in early-stage cervical cancer patients, primarily treated with surgery. Aim of this study was to identify cellular tumor pathways associated with pelvic lymph node metastasis in early-stage cervical cancer. EXPERIMENTAL DESIGN: Gene expression profiles (Affymetrix U133 plus 2.0) of 20 patients with negative (N(0)) and 19 with positive lymph nodes (N(+)), were compared with gene sets that represent all 285 presently available pathway signatures. Validation immunostaining of tumors of 274 consecutive early-stage cervical cancer patients was performed for representatives of the identified pathways. RESULTS: Analysis of 285 pathways resulted in identification of five pathways (TGF-beta, NFAT, ALK, BAD, and PAR1) that were dysregulated in the N(0), and two pathways (beta-catenin and Glycosphingolipid Biosynthesis Neo Lactoseries) in the N(+) group. Class comparison analysis revealed that five of 149 genes that were most significantly differentially expressed between N(0) and N(+) tumors (P < 0.001) were involved in beta-catenin signaling (TCF4, CTNNAL1, CTNND1/p120, DKK3, and WNT5a). Immunohistochemical validation of two well-known cellular tumor pathways (TGF-beta and beta-catenin) confirmed that the TGF-beta pathway (positivity of Smad4) was related to N(0) (OR: 0.20, 95% CI: 0.06-0.66) and the beta-catenin pathway (p120 positivity) to N(+) (OR: 1.79, 95%CI: 1.05-3.05). CONCLUSIONS: Our study provides new, validated insights in the molecular mechanism of lymph node metastasis in cervical cancer. pathway analysis of the microarray expression profile suggested that the TGF-beta and p120-associated noncanonical beta-catenin pathways are important in pelvic lymph node metastasis in early-stage cervical cancer.

AIM: To investigate the role of TGFbeta1 in invasion and metastasis in colorectal cancer by analysing TGFbeta1 correlated with depth of tumor invasion, stage and metastasis. METHODS: Serum TGFbeta1 levels were determined in 50 patients with colorectal cancer and 30 healthy volunteers using a TGFbeta1 enzyme-linked immunosorbent assay. TGFbeta1 expression in primary and lymph node metastatic lesions were detected in 98 cases of colorectal cancer by immunohistochemical staining and in situ hybridization. RESULTS: Serum levels of TGFbeta1 in patients with colorectal cancer(40+/-18 microg.L(-1)) were significantly higher than those in the healthy control group(19+/-8 microg.L(-1)), P<0.05. Elevated levels of serum TGFbeta1 were found in 60 % of patients with colorectal cancer when the mean +2 s was used as the upper limit of the normal range (35.1 microg.L(-1)). Increases in serum TGFbeta1 levels were significantly associated with Dukes stage (P<0.05), but there was no significant difference between Dukes stage B patients and Dukes stage C patients. In the cytoplasm of cancer cells, TGFbeta1 was immunostained in 37.8 % (37/98) of colorectal cancer, and this expression was confirmed by in situ hybridization. Among 35 cases of colorectal cancer with lymph node metastatic lesions, TGFbeta1 positive staining was found in 18 (51.4 %) cases of primary tumor, and 25 (71.4 %) cases with lymph node metastatic lesions, respectively. Of 17 cases w ith no staining in the primary lesion, 7 (41.2%) casesshowed TGFbeta1 staining in the metastatic lesion. Serum TGFbeta1 levels and TGFbeta1 expression in colorectal cancer tissues were correlated significantly with depth of tumor invasion, stage and metastasis. Patients in stage C-D,T3-T4 and with metastasis had significantly higher TGFbeta1 levels than patients in stage A-B,T1-T2 and without metastasis (P<0.05). CONCLUSION: These results suggest that transforming growth factor-beta1 is closely related to the invasion and metastasis of colorectal cancer. It increased the invasive and metastatic potential of tumor by altering a tumor microenvironment. TGFbeta1 may be used as a possible biomarker.

BACKGROUND: TGFbeta is an important cell growth regulator which may have a role in metastasis formation. Microsatellite unstable (MSI-H) colon cancer serves as a unique model to demonstrate this as most MSI-H colon cancers have a mutation in the transforming growth factor beta receptor II (TGFbetaRII) gene and a low metastatic rate. AIMS: To demonstrate an increase in invasion and metastasis in a MSI-H colorectal cancer cell line with a known mutation in TGFbetaRII. MATERIALS AND METHODS: By restoring the wild-type TGFbetaRII gene in the KM12C MSI-H colorectal carcinoma cell line with a known mutation in TGFbetaRII, we have demonstrated that both invasion and metastasis in this cell line was significantly increased. A mouse metastatic model have shown that liver metastases were increased in mice inoculated with cells containing a wild-type TGFbetaRII gene (42% for the transfected group compared with 15% for the control group; p = 0.0379), despite a reduction in the size of primary tumours. CONCLUSIONS: This study highlights an important mechanism which may contribute to the low metastatic rate of MSI-H colon cancers and demonstrates the importance of TGFbeta signalling in metastasis formation. Previous studies involving breast cancer cell lines have shown that blocking TGFbeta signalling results in a reduction in metastasis formation. This study is the first study to use a cell line with a low metastatic rate and TGFbetaRII mutations to demonstrate that restoring TGFbeta signalling increases the metastatic rate.

Colon adenocarcinoma is one of the most common fatal malignancies in Western countries. Progression of this cancer is dependent on tumor microenvironmental signaling molecules such as transforming growth factor-beta (TGF-beta) or acetylcholine (ACh). The present study was conducted to assess the influence of recombinant human transforming growth factor (rhTGF)-beta1 or ACh on nitric oxide (NO) and interleukin-1beta (IL-1beta) secretion by three human colon adenocarcinoma cell lines: HT29, LS180, and SW948, derived from different grade tumors (Duke's stage). The cells were cultured in 2D and 3D (spheroids) conditions. Colon carcinoma cells exhibited different sensitivities to rhTGF-beta1 or ACh dependent on the tumor grade and the culture model. ACh exhibited significant inhibitory effects towards NO, endothelial nitric oxide synthase (eNOS), and IL-1beta secretion especially by tumor cells derived form Duke's C stage of colon carcinoma. rhTGF-beta1 also decreased NO, IL-1beta, and eNOS expression, but its effect was lower than that observed after the administration of ACh. The inhibition of NO and IL-1beta production was more striking in 3D tumor spheroids than in 2D culture monolayers. Taken together, the TGF-beta1-ACh axis may regulate colon carcinoma progression and metastasis by altering NO secretion and influence inflammatory responses by modulating IL-1beta production.

metastasis causes most deaths from cancer yet mechanistic understanding and therapeutic options remain limited. Overexpression of the phosphatase PRL-3 (phosphatase of regenerating liver) is associated with metastasis of colon cancer. Here, we show that PRL-3 is a direct target of signaling by TGFbeta, which is broadly implicated in progression and metastasis. We found that suppression of PRL-3 expression by TGFbeta was mediated by Smad-dependent inhibition of PRL-3 transcription at the level of promoter activity. PRL-3 activation stimulated PI3K/AKT signaling that caused resistance to stress-induced apoptosis. PRL-3 overexpression promoted metastatic colonization in an orthotopic mouse model of colon cancer, whereas PRL-3 knockdown reduced metastatic potential. Altered metastatic phenotypes were not derivative of primary tumor development or local invasion but could be attributed to PRL-3-mediated cell survival. Our findings suggest that inhibiting PRL-3 expression might be an important mechanism through which TGFbeta suppresses metastasis in colon cancer. In addition, our findings suggest that loss of TGFbeta signaling, which occurs commonly during colon cancer progression, is sufficient to activate a PRL-3-mediated cell survival pathway that can selectively promote metastasis. Therefore, a major implication of our findings is that PRL-3 antagonists may offer significant value for antimetastatic therapy in patients with colon cancer.

The transforming growth factor beta (TGF-beta) signaling pathway has been considered both a tumor suppressor and a cancer promoter. Additionally, downregulation of cell adhesion molecules such as E-cadherin plays an important role in the metastatic potential of colorectal cancer (CRC). The aim of the present study was to evaluate TGF-beta, TGF-beta type I receptor (TGF-betaR1), TGF-beta type II receptor (TGF-betaR2), Smad4, pSmad2/3, and E-cadherin expression in colorectal carcinoma and to correlate the obtained data with other standard prognostic parameters, such as disease stage, metastases, and patient survival. TGF-beta, TGF-betaR1, TGF-betaR2, Smad4, pSmad2/3, and E-cadherin expression was evaluated immunohistochemically in 195 unrelated CRC specimens and the results subjected to various statistical analyses. TGF-beta was expressed in 71.28%, TGF-betaR1 in 61.0%, TGF-betaR2 in 54.4%, Smad4 in 61.5%, pSmad2/3 in 71.3%, and E-cadherin in 50.26% of the colorectal carcinoma samples tested. The correlation of immunoexpression with the clinicopathological parameters of CRC revealed that the high expression of TGF-beta and low expression of TGF-betaR1, TGF-betaR2, Smad4, pSmad2/3, and E-cadherin were correlated with tumor-node-metastasis (TNM) stage of disease. High TGF-beta expression and low TGF-betaR1, TGF-betaR2, Smad4, and pSmad2/3 expression were also correlated with lymph node metastasis. The Kaplan-Meier survival curves demonstrated a clear association of cancer-specific overall survival with high TGF-beta, as well as low TGF-betaR1, TGF-betaR2, Smad4, pSmad2/3, and E-cadherin expression. Our results suggest that TGF-beta, TGF-betaR1, TGF-betaR2, Smad4, pSmad2/3, and E-cadherin are closely related to TNM stage of CRC. Moreover, TGF-beta, TGF-betaR2, Smad4, pSmad2/3, and E-cadherin emerge as valuable independent biomarkers of prognosis in CRC patients.

Transforming growth factor beta (TGF-beta) plays important roles in tumor metastasis by regulating miRNAs expression. miR-182 is an important molecule in the regulation of cancer progression. The aim of the study is to assess the role of miR-182 in TGF-beta-induced cancer metastasis. In the present study, we found that miR-182 levels are significantly upregulated in GBC tissues compared with normal controls, and miR-182 expression is remarkably increased in primary tumors that subsequently metastasized, when compared to those primary tumors that did not metastasize. TGF-beta induces miR-182 expression in GBC cells, and overexpression of miR-182 promotes GBC cell migration and invasion, whereas miR-182 inhibition suppresses TGF-beta-induced cancer cell migration and invasion. The blockage of miR-182 by a specific inhibitor effectively inhibits pulmonary metastases in vivo. We further identified that the cell adhesion molecule1 (CADM1) is a new target gene of miR-182. miR-182 negatively regulates CADM1 expression in vitro and in vivo. Importantly, re-expression of CADM1 in GBC cells partially abrogates miR-182-induced cell invasion. CONCLUSIONS: miR-182 is an important mediator of GBC metastasis, thus offering a new target for the development of therapeutic agents against GBC.

The objective of this study was to identify genes regulated by thyroid hormone (T(3)) and associated with tumor invasion. The gene encoding furin, as previously identified by cDNA microarray, is known to be up-regulated by T(3) treatment, and stimulated furin production occurs in thyroidectomized rats after administration of T(3). Presently, by using serial deletion of the promoter and EMSAs, the T(3) response element on the furin promoter was localized to the -6317/-6302 region. T(3)-mediated furin up-regulation was cooperative with TGF-beta because T(3) induction increased after Smad3/4 addition. Furthermore, the invasiveness of HepG2-thyroid hormone receptor (TR) cells was significantly increased by T(3) treatment, perhaps due to furin processing of matrix metalloproteinase-2 and -9. In addition, furin up-regulation either by stable overexpression or T(3) and/or TGF-beta induction was evident in severe-combined immune-deficient mice inoculated with HepG2-TRalpha1 cells. The HepG2-furin mice displayed a higher metastasis index and tumor size than HepG2-neo mice. Notably, the increased liver and lung tumor number or size in the hyperthyroid severe-combined immune-deficient mice as well as TGF-beta mice was attributed specifically to furin overexpression in the HepG2-TRalpha1 cells. Furthermore, this study demonstrated that furin overexpression in some types of hepatocellular carcinomas is TR dependent and might play a crucial role in the development of hepatocellular carcinoma. Thus, T(3) regulates furin gene expression via a novel mechanism or in cooperation with TGF-beta to enhance tumor metastasis in vitro and in vivo.

Progression from chronic hepatitis C virus infection to cirrhosis then to hepatocellular carcinoma usually results in some protein changes in peripheral blood. We evaluated MAGE-4 mRNA, TGFbeta1 and AFP in peripheral blood as potential biochemical markers for diagnosis and prognosis of some complications of HCV infection. MAGE-4 mRNA in blood by reverse transcription polymerase chain reaction, serum TGF-Beta1 and AFP by ELISA was assayed in seventy-five individuals who were classified into five groups: group I (control) comprised fifteen apparently healthy volunteers, group II involved fifteen HCV-infected patients without cirrhosis, group III involved fifteen HCV fifteen HCV-infected patients with cirrhosis, group IV included fifteen HCV-infected patients with cirrhosis and early stage HCC, and group V included fifteen HCV cirrhotic patients and late-stage HCC. We found that the frequency of positivity of MAGE-4 among the late hepatoma group was 40 %, while in the early hepatoma group the positivity was 6.7 %. The results for TGF-Beta1 revealed a significant increase in serum TGF-Beta1 in groups IV and V as compared to control, II, III groups. The obtained results of AFP showed a significant positive increase in serum AFP in groups IV and V when compared to groups II and III. Detection of MAGE-4 transcripts in blood, especially with follow-up survey, may help to predict the prognosis and monitoring of the response to the therapy, and serum TGF-Beta1 level in HCC patients is directly correlated with metastasis and recurrence of tumors and increases gradually with the progression of HCC.

BACKGROUND: Hypermethylation of the TGFBI promoter has been shown to correlate with decreased expression of this gene in human tumor cell lines. In this study, we optimized a methylation-specific polymerase chain reaction (MSP) method and investigated the methylation status of the TGFBI promoter in human lung and prostate cancer specimens. METHODS: Methylation-specific primers were designed based on the methylation profiles of the TGFBI promoter in human tumor cell lines, and MSP conditions were optimized for accurate and efficient amplification. Genomic DNA was isolated from lung tumors and prostatectomy tissues of prostate cancer patients, bisulfite-converted, and analyzed by MSP. RESULTS: Among 50 lung cancer samples, 44.0% (22/50) harbored methylated CpG sites in the TGFBI promoter. An analysis correlating gene methylation status with clinicopathological cancer features revealed that dense methylation of the TGFBI promoter was associated with a metastatic phenotype, with 42.9% (6/14) of metastatic lung cancer samples demonstrating dense methylation vs. only 5.6% (2/36) of primary lung cancer samples (p < 0.05). Similar to these lung cancer results, 82.0% (41/50) of prostate cancer samples harbored methylated CpG sites in the TGFBI promoter, and dense methylation of the promoter was present in 38.9% (7/18) of prostate cancer samples with the feature of locoregional invasiveness vs. only 19.4% (6/31) of prostate cancer samples without locoregional invasiveness (p < 0.05). Furthermore, promoter hypermethylation correlated with highly reduced expression of the TGFBI gene in human lung and prostate tumor cell lines. CONCLUSION: We successfully optimized a MSP method for the precise and efficient screening of TGFBI promoter methylation status. Dense methylation of the TGFBI promoter correlated with the extent of TGFBI gene silencing in tumor cell lines and was related to invasiveness of prostate tumors and metastatic status of lung cancer tumors. Thus, TGFBI promoter methylation can be used as a potential prognostic marker for invasiveness and metastasis in prostate and lung cancer patients, respectively.

Lung cancer is a highly malignant carcinoma, and most deaths of lung cancer are caused by metastasis. The alterations associated with epithelial-to-mesenchymal transition (EMT) may be related to the cancer cell metastasis. Nevertheless, the mechanism of lung cancer metastasis remains unclear. We conducted a study in vitro to investigate whether transforming growth factor-beta1 (TGF-beta1) could induce changes of, such as cell morphology, expression of relative protein markers, and cellular motile and invasive activities. In this research, the changes of cell morphology were first investigated under a phase contrast microscope, then western blotting was employed to detect the expression of E-cadherin, vimentin, and fibronectin, and finally cell motility and invasion were evaluated by cell wound-healing as well as invasion assays. The data indicated that human lung adenocarcinoma cell lines, A-549 and PC-9 cells of epithelial cell characteristics, were induced to undergo EMT by TGF-beta1. Following TGF-beta1 treatment, cells showed dramatic morphological changes assessed by phase contrast microscopy, accompanied by decreased epithelial marker E-cadherin and increased mesenchymal markers vimentin and fibronectin. More importantly, cell motility and invasion were also enhanced in the EMT process. These results indicated that TGF-beta1 may promote lung adenocarcinoma invasion and metastasis via the mechanism of EMT.

Medulloblastoma (MB) is the most common malignant brain tumor of childhood. Very little is known about aggressive forms of this disease, such as metastatic or recurrent MBs. In order to identify pathways involved in aggressive MB pathophysiology, we performed unbiased, whole genome microarrays on MB tumors at both the human and murine levels. Primary human MBs were compared, transcriptomically, to their patient-matched recurrent or metastatic tumors. expression profiling was also performed on murine tumors from two spontaneously developing MB mouse models (Ptch+/- and Smo/Smo) that present with differing clinical severities. At both the human and murine levels we identified transforming growth factor-beta (TGF-beta) as a potential contributor to MB progression/metastasis. Smad3, a major downstream component of the TGF-beta pathway, was also evaluated using immunohistochemistry in malignant human tissues and was shown to correlate with MB metastasis and survival. Similarly, Smad3 expression during development identified a subset of cerebellar neuronal precursors as putative cells of origin for the Smad3-positive MBs. To our knowledge, this is the first study that links TGF-beta to MB pathogenesis. Our research suggests that canonical activation of this pathway leads to better prognosis for patients.

The tumor invasive phenotype driven by seprase expression/activity has been widely examined in an array of malignant tumor cell types; however, very little is known about the transcriptional regulation of this critical protease. Seprase (also named fibroblast activation protein-alpha, antiplasmin-cleaving enzyme, and dipeptidyl prolyl peptidase 5) is expressed at high levels by stromal fibroblast, endothelial, and tumor cells in a variety of invasive tumors but is undetectable in the majority of normal adult tissues. To examine the transcriptional regulation of the gene, we cloned the human seprase promoter and demonstrated that endogenous seprase expression and exogenous seprase promoter activity are high in invasive melanoma cells but not in non-invasive melanoma cells/primary melanocytes. In addition, we identified a crucial TGF-beta-responsive cis-regulatory element in the proximal seprase promoter region that enabled robust transcriptional activation of the gene. Treatment of metastatic but not normal/non-invasive cells with TGF-beta1 caused a rapid and profound up-regulation of endogenous seprase mRNA, which coincided with an abolishment of the negative regulator c-Ski, and an increase in binding of Smad3/4 to the seprase promoter in vivo. Blocking TGF-beta signaling in invasive melanoma cells through overexpression of c-Ski, chemically using SB-431542, or with a neutralizing antibody against TGF-beta significantly reduced seprase mRNA levels. Strikingly, RNAi of seprase in invasive cells greatly diminished their invasive potential in vitro as did blocking TGF-beta signaling using SB-431542. Altogether, we found that seprase is transcriptionally up-regulated in invasive melanoma cells via the canonical TGF-beta signaling pathway, supporting the roles of both TGF-beta and seprase in tumor invasion and metastasis.

Members of the integrin family recognize a variety of spatially-restricted extracellular ligands. Classically, ligation of integrins activates cytoplasmic signals in the integrin-expressing cell and contributes to cell adhesion, migration, proliferation and survival. At least two members of this family, alphavbeta6 and alphavbeta8 perform an additional function, activation of latent complexes of transforming growth factor beta. In effect, this process allows integrins on one cell to activate signals on adjacent (in the case of alphavbeta6) or nearby cells (in the case of alphavbeta8). Integrin-mediated TGFbeta activation has been shown to play important roles in modulating tissue fibrosis, acute lung injury and pulmonary emphysema. Given the important roles that TGFbeta plays in modulating epithelial cell growth, epithelial-to-mesenchymal transformation and tumor invasion and metastasis, integrin-mediated TGFbeta activation is likely to play important roles in tumor growth and metastasis.

TGF-beta signaling regulates tumorigenesis and in human cancer its signaling pathways are often modified during tumor progression. Prior to initiation and early during progression TGF-beta acts upon the epithelium as a tumor suppressor, however at later stages it is often a tumor promoter. Over the years, many studies have focused on the epithelial cell autonomous role for TGF-beta, however, TGF-beta is not strictly limited to this compartment in vivo. Recent studies addressing TGF-beta mediated stromal-epithelial interactions have significantly improved our understanding related to the regulation of cancer. In addition, stromal fibroblast cell autonomous effects have been observed in response to TGF-beta stimulation. According to the current literature and experimental evidence, TGF-beta is a potent ligand that regulates carcinoma initiation, progression and metastasis through a broad and complex spectrum of interdependent interactions.

In HER2 (ErbB2)-overexpressing cells, transforming growth factor beta (TGF-beta), via activation of phosphoinositide-3 kinase (PI3K), recruits actin and actinin to HER2, which then colocalizes with Vav2, activated Rac1, and Pak1 at cell protrusions. This results in prolonged Rac1 activation, enhanced motility and invasiveness, Bad phosphorylation, uncoupling of Bad/Bcl-2, and enhanced cell survival. The recruitment of the HER2/Vav2/Rac1/Pak1/actin/actinin complex to lamellipodia was abrogated by actinin siRNAs, dominant-negative (dn) p85, gefitinib, and dn-Rac1 or dn-Pak1, suggesting that the reciprocal interplay of PI3K, HER2 kinase, and Rac GTPases with the actin cytoskeleton is necessary for TGF-beta action in oncogene-overexpressing cells. Thus, by recruiting the actin skeleton, TGF-beta "cross-links" this signaling complex at cell lamellipodia; this prolongs Rac1 activation and increases metastatic properties and survival of HER2-overexpressing cells.

PURPOSE OF REVIEW: Most cancers are characterized by excessive transforming growth factor-beta production by tumors, which can promote tumor growth and mediate epithelial-to-mesenchymal transition. Transforming growth factor-beta also has the ability to overproduce extracellular matrix components in response to injury and other stimuli. There are many strategies undergoing current evaluation for inhibiting the deleterious biological effects of transforming growth factor-beta by disrupting its signaling at various levels. The current review focuses on the recent advances made in this area, and the potential of these strategies in the clinical treatment of cancer and fibrosis. RECENT FINDINGS: Four main strategies used most recently for disrupting transforming growth factor-beta signaling are brought into focus in this review: inhibition or sequestration of the transforming growth factor-beta protein ligands, inhibition of transforming growth factor-beta receptor kinase activity, inhibition of SMAD signaling downstream of transforming growth factor-beta kinase activity and restoration of antitumor immunity upon transforming growth factor-beta inhibition. Various techniques currently used to employ these four strategies are discussed. SUMMARY: Several lines of evidence suggest that altered transforming growth factor-beta signaling contributes to tumor progression and metastasis as well as development of fibrosis. Accumulating data from preclinical and clinical studies indicate that antagonizing aberrant transforming growth factor-beta signaling is a promising novel therapeutic approach in cancer and fibrotic disorders.

The objective of this study was to identify genes regulated by thyroid hormone (T(3)) and associated with tumor invasion. The gene encoding furin, as previously identified by cDNA microarray, is known to be up-regulated by T(3) treatment, and stimulated furin production occurs in thyroidectomized rats after administration of T(3). Presently, by using serial deletion of the promoter and EMSAs, the T(3) response element on the furin promoter was localized to the -6317/-6302 region. T(3)-mediated furin up-regulation was cooperative with TGF-beta because T(3) induction increased after Smad3/4 addition. Furthermore, the invasiveness of HepG2-thyroid hormone receptor (TR) cells was significantly increased by T(3) treatment, perhaps due to furin processing of matrix metalloproteinase-2 and -9. In addition, furin up-regulation either by stable overexpression or T(3) and/or TGF-beta induction was evident in severe-combined immune-deficient mice inoculated with HepG2-TRalpha1 cells. The HepG2-furin mice displayed a higher metastasis index and tumor size than HepG2-neo mice. Notably, the increased liver and lung tumor number or size in the hyperthyroid severe-combined immune-deficient mice as well as TGF-beta mice was attributed specifically to furin overexpression in the HepG2-TRalpha1 cells. Furthermore, this study demonstrated that furin overexpression in some types of hepatocellular carcinomas is TR dependent and might play a crucial role in the development of hepatocellular carcinoma. Thus, T(3) regulates furin gene expression via a novel mechanism or in cooperation with TGF-beta to enhance tumor metastasis in vitro and in vivo.

TGFbeta ligands act as tumor suppressors in early stage tumors but are paradoxically diverted into potent prometastatic factors in advanced cancers. The molecular nature of this switch remains enigmatic. Here, we show that TGFbeta-dependent cell migration, invasion and metastasis are empowered by mutant-p53 and opposed by p63. Mechanistically, TGFbeta acts in concert with oncogenic Ras and mutant-p53 to induce the assembly of a mutant-p53/p63 protein complex in which Smads serve as essential platforms. Within this ternary complex, p63 functions are antagonized. Downstream of p63, we identified two candidate metastasis suppressor genes associated with metastasis risk in a large cohort of breast cancer patients. Thus, two common oncogenic lesions, mutant-p53 and Ras, selected in early neoplasms to promote growth and survival, also prefigure a cellular set-up with particular metastasis proclivity by TGFbeta-dependent inhibition of p63 function.

During breast cancer progression, transforming growth factor-beta (TGF-beta) switches from a tumor suppressor to a pro-metastatic molecule. Several recent studies suggest that this conversion in TGF-beta function depends upon fundamental changes in the TGF-beta signaling system. We show here that these changes in TGF-beta signaling are concomitant with aberrant expression of the focal adhesion protein, p130Cas. Indeed, elevating expression of either the full-length (FL) or just the carboxyl terminus (CT) of p130Cas in mammary epithelial cells (MECs) diminished the ability of TGF-beta1 to activate Smad2/3, but increased its coupling to p38 MAPK. This shift in TGF-beta signaling evoked (i) resistance to TGF-beta-induced growth arrest, and (ii) acinar filling upon three-dimensional organotypic cultures of p130Cas-FL or -CT expressing MECs. Furthermore, rendering metastatic MECs deficient in p130Cas enhanced TGF-beta-stimulated Smad2/3 activity, which restored TGF-beta-induced growth inhibition both in vitro and in mammary tumors produced in mice. Additionally, whereas elevating TbetaR-II expression in metastatic MECs had no affect on their phosphorylation of Smad2/3, this event markedly enhanced their activation of p38 MAPK, leading to increased MEC invasion and metastasis. Importantly, depleting p130Cas expression in TbetaR-II-expressing metastatic MECs significantly increased their activation of Smad2/3, which (i) reestablished the physiologic balance between canonical and noncanonical TGF-beta signaling, and (ii) reversed cellular invasion and early mammary tumor cell dissemination stimulated by TGF-beta. Collectively, our findings identify p130Cas as a molecular rheostat that regulates the delicate balance between canonical and noncanonical TGF-beta signaling, a balance that is critical to maintaining the tumor suppressor function of TGF-beta during breast cancer progression.

Transforming growth factor-beta1 (TGF-beta1) is known to suppress antitumor immune responses, and its overexpression is closely associated with a poor prognosis in patients with malignant tumors. Moreover, TGF-beta1 29T>C genetic polymorphism is known to affect survival among breast cancer patients. The relationship between TGF-beta1 polymorphism and the clinicopathological characteristics of non-small cell lung cancer remains unknown, however. The study participants were 91 Japanese patients who underwent curative surgery for adenocarcinoma of the lung. DNA was extracted from tumor samples, and TGF-beta1 29T>C genetic polymorphism was investigated using the polymerase chain reaction-restriction fragment length polymorphism method, after which genotype was correlated with clinicopathological factors. There were no differences between the TGF-beta1 29TT and 29TC+CC genotypes with respect to age, sex, histological differentiation grade, tumor size, or pathological stage. However, the frequency of nodal metastasis was significantly greater in the TGF-beta1 29TC+CC group than the TGF-beta1 29TT group. Multivariate logistic regression analysis of lymph node metastasis revealed that male, tumor size, differentiation grade, and TGF-beta1 29TC+CC genotypes (hazard ratio, 5.26; 95% CI, 1.03-40.0; P = 0.045) are factors associated with a significantly greater likelihood of developing lymph node metastasis. TGF-beta1 29T>C genetic polymorphism is an independent factor associated with lymph node metastasis in adenocarcinoma of the lung.

Cellular niches in adult tissue can harbour dysregulated microenvironments that become the driving force behind disease progression. The major environmental change when metastatic cells arrive in the bone is the destruction of mineralized type I collagen matrix. Once metastatic niches establish in bone, the invading tumour cells initiate a vicious cycle of osteolytic lesion formation via the dysregulation of paracrine signals and uncoupling of normal bone resorption and production. Here we report that the collagen receptor Endo180 (CD280, MRC2, uPARAP) participates in collagen deposition by primary human osteoblasts during de novo osteoid formation. This newly recognized function of Endo180 was suppressed in osteoblasts following heterotypic direct cell-cell contact in co-culture with prostate tumour cells. Reciprocal Endo180 up-regulation in osteolytic prostate tumour cells (PC3 and DU145) followed their direct contact with osteoblasts and promoted de novo collagen internalization, which is a previously characterized function of the constitutively recycling Endo180 receptor. The osteoblastic suppression and tumour cell-associated enhancement of Endo180 expression were equally sustained in these direct co-cultures. These findings are the first to demonstrate that increased tumour cell participation in collagen degradation and decreased collagen formation by osteoblasts in the osteolytic microenvironment are linked to the divergent regulation of a collagen-binding receptor. Immunohistochemical analysis of core biopsies from bone metastasis revealed higher levels of Endo180 expression in tumour cell foci than cells in the surrounding stroma. Additional experiments in prostate cell-osteoblast co-cultures indicate that divergent regulation of Endo180 is the result of dysregulated TGFbeta1 signalling. The findings of this study provide a rationale for targeting collagen remodelling by Endo180 in bone metastases and other collagen matrix pathologies.

TGFbeta1 is a major fibrotic factor and its actions involve induction of epithelial cell death, together with the stimulation and transdifferentiation of fibroblasts into collagen- and fibronectin-secreting myofibroblasts. These actions of TGFbeta1 are also consistent with a pro-metastatic role, by aiding epithelial cell escape through mesenchymal tissues. Recently IGFBP-5 has been described as a pro-fibrotic (pro-metastatic?) agent and the aim of this study was to compare and contrast the actions of IGFBP-5 with TGFbeta1. We used NMuMG cells and cloned stable epithelial and mesenchymal lines from the parent cells. TGFbeta1 induced apoptosis and/or EMT in the epithelial cells, whereas it enhanced mesenchymal cell survival and migration. IGFBP-5, in contrast, enhanced both cell-cell and cell-ECM adhesion and also improved wound closure in epithelial cells whereas, in mesenchymal cells, IGFBP-5 decreased adhesion and migration. Furthermore, IGFBP-5 was able to antagonise the actions of TGFbeta1. In a co-culture model simulating epithelial-mesenchymal boundaries, IGFBP-5 was able to antagonise the disruptive transgressions induced by TGFbeta1. Overall, these findings suggest that IGFBP-5 is important in maintaining epithelial-mesenchymal boundaries and thus may limit metastasis and fibrosis by inducing an orderly repair mechanism, very distinct from the fibrotic disruption induced by TGFbeta1. A role for IGFBP-5 in the inhibition of metastasis is supported by immunohistochemical studies of breast cancer microarrays, where we show that elevated IGFBP-5 expression is associated with increased disease-free survival.

PURPOSE: Brain metastasis (BM) from non-small cell lung cancer (NSCLC) is relatively common, but identifying which patients will develop brain metastasis has been problematic. We hypothesized that genotype variants in the TGF-beta signaling pathway could be a predictive biomarker of brain metastasis. PATIENTS AND METHODS: We genotyped 33 SNPs from 13 genes in the TGF-beta signaling pathway and evaluated their associations with brain metastasis risk by using DNA from blood samples from 161 patients with NSCLC. Kaplan-Meier analysis was used to assess brain metastasis risk; Cox hazard analyses were used to evaluate the effects of various patient and disease characteristics on the risk of brain metastasis. RESULTS: The median age of the 116 men and 45 women in the study was 58 years; 62 (39%) had stage IIIB or IV disease. Within 24 months after initial diagnosis of lung cancer, brain metastasis was found in 60 patients (37%). Of these 60 patients, 16 had presented with BM at diagnosis. Multivariate analysis showed the GG genotype of SMAD6: rs12913975 and TT genotype of INHBC: rs4760259 to be associated with a significantly higher risk of brain metastasis at 24 months follow-up (hazard ratio [HR] 2.540, 95% confidence interval [CI] 1.204-5.359, P = 0.014; and HR 1.885, 95%

Oral squamous cell carcinoma (OSCC) is a world-wide health problem and its incidence accounts for 1.9-3.5% of all malignant tumors. Transforming growth factor beta/Smads (TGF-beta/Smads) signaling pathway plays an important role in oncogenesis, but its function and molecular mechanisms in OSCC remain unclear. expression of transforming growth factor-beta receptor type II (TbetaRII) and Smad4 was studied by immunohistochemistry in 108 OSCC patients and 10 normal controls. Function and molecular mechanisms of TGF-beta/Smads signaling pathway was then investigated in two human tongue squamous carcinoma cell lines with high and low metastasis (Tb and Tca8113) by RT-PCR, Western Blot, immunofluorescence, cell growth curve and flow cytometry (FCM), respectively. TbetaRII and Smad4 were significantly down-regulated in tumor tissues (with or without lymph node metastasis) compared to normal oral epithelium tissues (P < 0.05). TGF-beta1 induced arrest of the cell cycle rather than cell death in Tca8113 and Tb cells, and this influence was mediated by the increasing the expression and changing the location of its downstream components of TGF-beta1/Smads signaling pathway. TGF-beta1 rapidly increased the expression of p15 and p21 in both Tca8113 and Tb cells. TGF-beta1 did not increase p27 expression in Tca8113 cells, but p27 expression was increased in Tb cells. These indicated that TGF-beta1 induced G(1) arrest of cell cycle through a different regulating pathway in Tb cells compared with Tca8113 cells. Thus, we conclude that TGF-beta/Smads signaling pathway play a important role on cell growth and metastasis potential in OSCC.

The transforming growth factor-beta (TGF-beta) signaling pathway plays critical roles in the development of various diseases. The current study investigated whether TGF-beta was involved in the pathogenesis of osteosarcoma from the genetic polymorphism perspective and serum level perspective. We first examined two TGF-beta1 polymorphisms, rs1800469C/T and rs1800470T/C, in 202 osteosarcoma patients and 216 healthy controls. Data revealed that the prevalence of rs1800470TT genotype and T allele was significantly elevated in patients than in controls (odds ratio [OR]=2.28, 95% confidence interval [CI]: 1.30-3.98, p<0.001, and OR=1.49, 95% CI: 1.14-1.96, p<0.001). Function analyses showed that healthy controls carrying rs1800470TT genotype had a significantly higher serum level of TGF-beta than those carrying the rs1800470CC genotype (191.1+/-15.7 pg/mL vs. 129.4+/-10.9 pg/mL, p=0.003). We then compared the serum level of TGF-beta between osteosarcoma patients and healthy controls. Results demonstrated a significantly increased serum level of TGF-beta in patients than in controls. Further analyses identified that patients with metastasis had augmented levels of serum TGF-beta than those without metastasis. These data indicate that TGF-beta may be closely involved in the pathogenesis of osteosarcoma.

Transforming growth factor-beta (TGF-beta) is thought to play a role in the pathobiological progression of ovarian cancer because this peptide hormone is overexpressed in cancer tissue, plasma, and peritoneal fluid. In the current study, we investigated the role of the TGF-beta/Smad3 pathway in ovarian cancer metastasis by regulation of an epithelial-to-mesenchymal transition. When cancer cells were cultured on plastic, TGF-beta1, TGF-beta2, and TGF-beta3 induced pro-matrix metalloproteinase (MMP) secretion, loss of cell-cell junctions, down-regulation of E-cadherin, up-regulation of N-cadherin, and acquisition of a fibroblastoid phenotype, consistent with an epithelial-to-mesenchymal transition. Furthermore, Smad3 small interfering RNA transfection inhibited TGF-beta-mediated changes to a fibroblastic morphology, but not MMP secretion. When cancer cells were cultured on a three-dimensional collagen matrix, TGF-beta1, TGF-beta2, and TGF-beta3 stimulated both pro-MMP and active MMP secretion and invasion. Smad3 small interfering RNA transfection of cells cultured on a collagen matrix abrogated TGF-beta-stimulated invasion and MMP secretion. Analysis of Smad3 nuclear expression in microarrays of serous benign tumors, borderline tumors, and cystadenocarcinoma revealed that Smad3 expression could be used to distinguish benign and borderline tumors from carcinoma (P = 0.006). Higher Smad3 expression also correlated with poor survival (P = 0.031). Furthermore, a direct relationship exists between Smad3 nuclear expression and expression of the mesenchymal marker N-cadherin in cancer patients (P = 0.0057). Collectively, these results implicate an important role for the TGF-beta/Smad3 pathway in mediating ovarian oncogenesis by enhancing metastatic potential.

Ovarian cancer metastasis is characterized by the shedding of malignant cells from the surface of the ovary and their implantation onto the peritoneal surface, which lines the abdominal cavity. As the factors promoting this process are poorly understood, we investigated the ovarian cancer-peritoneal interaction by means of in vitro coculture experiments with ovarian cancer (OVCAR-5 and SKOV-3) and peritoneal (LP-9) cells. One of the proteins differentially expressed in the coculture secretome was identified by MALDI-TOF/TOF mass spectrometry as the extracellular matrix protein transforming growth factor-beta-induced protein (TGFBIp, also known as betaig-H3). Immunohistochemistry showed high TGFBIp levels in normal surface ovarian epithelial and peritoneal cells, whereas TGFBIp levels in primary serous ovarian carcinomas and matching metastatic implants was very low. In functional in vitro experiments, treatment with recombinant TGFBIp significantly increased the motility and invasiveness of OVCAR-5 and SKOV-3 cells and significantly increased ovarian cancer cell (OVCAR-5, OVCAR-3 and SKOV-3) adhesion to LP-9 cells. TGFBIp was found to be processed at both the N- and C-terminus in the secretome of the ovarian cancer-peritoneal cell coculture. Plasmin inhibitors blocked TGFBIp processing and significantly reduced OVCAR-5 cell adhesion to peritoneal cells. We conclude that TGFBIp expressed by peritoneal cells increases the metastatic potential of ovarian cancer cells. TGFBIp is therefore a potential novel therapeutic target against ovarian cancer.

OBJECTIVE: To detect the expression of the protein of TGF-beta1 and E-cadherin in the primary and metastatic lesions of ovarian carcinoma and explore the mechanism of the metastasis of ovarian carcinoma. METHODS: Immunohistochemistry (IHC) was performed to detect the expression of TGF-beta1 and E-cadherin proteins in primary and metastatic ovarian carcinoma, benign epithelial ovarian tumor and normal ovarian tissue. RESULTS: The expression of TGF-beta1 was significantly higher in ovarian carcinoma (67.2%) than in benign tumors (28.6%) and normal ovarian tissue (18.9%) (Chi2=26.94, P<0.001), but E-cadherin expression showed a reverse pattern. TGF-beta1 expression in the primary ovarian carcinoma carcinoma was associated with the FIGO stage, lymph metastasis and ascites of the tumor (P=0.01, P=0.01, and P=0.04, respectively). E-cadherin expression in the tumor was associated with the differentiation (P=0.02) and lymph metastasis of ovarian carcinoma (P=0.04). The expressions of TGF-beta1 and E-cadherin were all significantly lower in the primary tumors than in the metastatic tumor (Chi2=4.70, P=0.03; Chi2=5.91, P=0.015). A significant correlation was found between the expressions of the TGF-beta1 and E-cadherin in the primary carcinoma (Kappa value of -0.32, P=0.01). CONCLUSION: TGF-beta1 and E-cadherin are closely associated with the metastasis of ovarian carcinoma and might be potential targets for controlling the metastasis of ovarian carcinoma.

Tissue transglutaminase (TG2), an enzyme involved in cell proliferation, differentiation and apoptosis is overexpressed in ovarian carcinomas, where it modulates epithelial-to-mesenchymal transition (EMT) and promotes metastasis. Its regulation in ovarian cancer (OC) remains unexplored. Here, we show that transforming growth factor (TGF)-beta, a cytokine involved in tumor dissemination is abundantly secreted in the OC microenvironment and induces TG2 expression and enzymatic activity. This is mediated at transcriptional level by SMADs and by TGF-beta-activated kinase 1-mediated activation of the nuclear factor-kappaB complex. TGF-beta-stimulated OC cells aggregate as spheroids, which enable peritoneal dissemination. We show that TGF-beta-induced TG2 regulates EMT, formation of spheroids and OC metastasis. TG2 knock-down in OC cells decreases the number of cells harboring a cancer stem cell phenotype (CD44+/CD117+). Furthermore, CD44+/CD117+ cells isolated from human ovarian tumors express high levels of TG2. In summary, TGF-beta-induced TG2 enhances ovarian tumor metastasis by inducing EMT and a cancer stem cell phenotype.

OBJECTIVE: To investigate the relation of transfer growth factor (TGF-beta1) and beta-glucuronidase (beta-GCD) on the occurrence and progress of pancreatic cancer. METHODS: The expression of TGF-beta1 and beta-GCD in the pancreatic cancer tissue and normal pancreatic tissue was determined synchronously using ABC method of immunohistochemistry. RESULTS: The percentage of TGF-beta1 positive cells was significantly higher in pancreatic cancer tissue (43.8%+/-5.2%) than in adjacent pancreatic tissue (28.7%+/-3.6%, P<0.01). The worse the cancer cells differentiated and lymph nodes metastasis, the more over-expression of TGF-beta1. The percentage of beta-GCD positive cells was also significantly higher in the pancreatic cancer tissue (62.5%+/-4.1%) than in the adjacent pancreatic tissue (33.5%+/-2.8%, P<0.01). The degree of over-expression of beta-GCD was related to the degree of cancer cells differentiation, but not to the lymph nodes metastasis. The expression of TGF-beta1 was significantly correlated with the expression of beta-GCD in pancreatic cancer tissue. CONCLUSIONS: The genesis of pancreatic cancer results from multi-factor, multi-step and multi-gene variation. The synchronous detection of TGF-beta1 and beta-GCD helps to determine the malignant degree of tumors and the prognosis of patients with such disease.

BACKGROUND: The purpose of our study was to investigate the immunohistochemical expression of TGF-beta1 and p27 in pancreatic adenocarcinomas and to compare the findings with the clinicopathological features and survival. We also aimed to evaluate the expression of TGF-beta1 and p27 in the context of other cell cycle and proliferation markers such as cyclin D1 and Ki-67. METHODS: We examined TGF-beta1 and p27 expression immunohistochemically in 63 cases of invasive ductal adenocarcinoma of the pancreas. Standard streptavidin-biotin immunperoxidase method was used for immunostaining and the stained slides were examined microscopically using semiquantitative criteria. RESULTS: TGF-beta1 stained the cytoplasms of the tumor cells in 43 cases [68.3%]. There was a statistically significant difference among TGF-beta1 staining scores in terms of clinicopathologic factors such as blood vessel invasion, stage and distant metastasis [p < 0.05]. Of the 63 tumors evaluated 23 [36.5%] were positive for p27 within the nucleus. An inverse correlation was found between p27 immunoreactivity and grade [p < 0.05]. But no significant correlation was found between p27 and other parameters. Among the patients with survival data 27 patients had RO resections and these cases were considered in survival analysis. In the univariate analysis, neither TGF-beta1 nor p27 expression was related with patient survival. CONCLUSION: Our findings suggest that in pancreatic carcinoma, TGF-beta1 expression is related to tumor growth and metastasis. But it is not associated with cell cycle proteins. p27 expression is reduced in pancreatic adenocarcinomas and decreased protein levels of p27 may play a role in the differentiation of pancreatic cancer.

Human pancreatic cancer invasion and metastasis have been found to correlate with increased levels of active matrix metalloproteinase 2 (MMP-2). The multifunctional cytokine transforming growth factor beta 1 (TGF-beta1) has been shown to increase both secretion of MMP-2 and invasion by several pancreatic cancer cell types. In the present study, we investigated the signaling pathway involved in TGF-beta1-promoted MMP-2 secretion and invasion by human pancreatic cancer cells SW1990. Using specific inhibitors, we found that stimulation of these tumor cells with TGF-beta1 induced secretion and activation of the collagenase MMP-2, which was required for TGF-beta1-stimulated invasion. Our results also indicate that signaling events involved in TGF-beta1-enhanced SW1990 invasiveness comprehend activation of Rac1 followed by generation of reactive oxygen species through nicotinamide adenine dinucleotide phosphate-oxidase, activation of nuclear factor-kappa beta, release of interleukin-6, and secretion and activation of MMP-2.

All the specimens were marked by CD31 antibody, the expression of nm23HlmRNA, TGF-beta1mRNA was detected in 42 cases of prostate cancer in situ hybridization with EnVision and Leica-Qwin computer image analysis system. The Weidner's highest vessel density counting method was used to analysis the microvessel density(MVD) of the specimens,and the patients' viability rate after operation was investigated. The correlation between the expression of nm23H1mRNA, TGF-betamRNA,CD31 and neoangiogenesis, hyperplasia of microvessel, tumor metastases in prostate cancer was studied. The positive expression of nm23H1mRNA in prostate cancer was 66.67% (28 cases). There was negative correlation between the positive expression of nm23H1mRNA and bone metastasizing, TNM staging,MVD in prostate cancer (P < 0.05). The positive expression of TGF-beta1mRNA was 78.75% (33 cases), and was positive correlative to the bone metastasis, TNM stages, MVD in prostate cancer (P < 0.05). It is significantly different (P < 0.01 or P < 0.05) with that in adjacent nontumorous tissue. The MVD (78.51 +/- 10.29/mm2) in prostate cancer was significantly (P < 0.05) higher than that in adjacent nontumorous tissue (34.19 +/- 9.27/mm2). The MVD (92.41 +/- 15.42/mm2) in those who died in five years (18 cases) was significantly higher (P < 0.05) than that (62.79 +/- 13.58/mm2) in those who were still alive. In tumor pathology grading,different differentiation, the difference of nm23H1mRNA positive expression was statistically significant (P < 0.05). Higher the nm23H1mRNA expressed,lower the bone metastasized,and higher the viability rate was. Therefore, the nm23H1 gene was thought to have the effect of suppressing prostate cancer occurring and bone metastasizing. Higher the TGF-beta1mRNA expressed, higher the tumor bone metastasized, and lower the viability rate was. Therefore, the TGF-beta1 gene was thought to have the promote genesis and metastasize of prostate cancer. There is close correlation between the CD31 expression, MVD and prostate cancer bone metastasizing. The higher MVD level indicated neoangiogenesis in prostate cancer. TGF-beta1mRNA promote neoangiogenesis induced by tumor and play an important role in bone metastasizing.

Growth and survival of tumors at a site of metastasis involve interactions with stromal cells in the surrounding environment. Stromal cells aid tumor cell growth by producing cytokines as well as by modifying the environment surrounding the tumor through modulation of the extracellular matrix (ECM). Small leucine-rich proteoglycans (SLRPs) are biologically active components of the ECM which can be altered in the stroma surrounding tumors. The influence tumor cells have on stromal cells has been well elucidated. However, little is understood about the effect metastatic cancer cells have on the cell biology and behavior of the local stromal cells. Our data reveal a significant down-regulation in the expression of ECM components such as collagens I, II, III, and IV, and the SLRPs, decorin, biglycan, lumican, and fibromodulin in stromal cells when grown in the presence of two metastatic prostate cancer cell lines PC3 and DU145. Interestingly, TGF-beta down-regulation was observed in stromal cells, as well as actin depolymerization and increased vimentin and alpha5beta1 integrin expression. MT1-MMP expression was upregulated and localized in stromal cell protrusions which extended into the ECM. Moreover, enhanced stromal cell migration was observed after cross-talk with metastatic prostate tumor cells. Xenografting metastatic prostate cancer cells together with "activated" stromal cells led to increased tumorigenicity of the prostate cancer cells. Our findings suggest that metastatic prostate cancer cells create a metastatic niche by altering the phenotype of local stromal cells, leading to changes in the ECM.

Hypoxia and transforming growth factor-beta1 (TGF-beta1) increase vascular endothelial growth factor A (VEGFA) expression in a number of malignancies. This effect of hypoxia and TGF-beta1 might be responsible for tumor progression and metastasis of advanced prostate cancer. In the present study, TGF-beta1 was shown to induce VEGFA(165) secretion from both normal cell lines (HPV7 and RWPE1) and prostate cancer cell lines (DU145 and PC3). Conversely, hypoxia-stimulated VEGFA(165) secretion was observed only in prostate cancer cell lines. Hypoxia induced TGF-beta1 expression in PC3 prostate cancer cells, and the TGF-beta type I receptor (ALK5) kinase inhibitor partially blocked hypoxia-mediated VEGFA(165) secretion. This effect of hypoxia provides a novel mechanism to increase VEGFA expression in prostate cancer cells. Although autocrine signaling of VEGFA has been implicated in prostate cancer progression and metastasis, the associated mechanism is poorly characterized. VEGFA activity is mediated via VEGF receptor (VEGFR) 1 (Flt-1) and 2 (Flk-1/KDR). Whereas VEGFR-1 mRNA was detected in normal prostate epithelial cells, VEGFR-2 mRNA and VEGFR protein were expressed only in PC3 cells. VEGFA(165) treatment induced phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) in PC3 cells but not in HPV7 cells, suggesting that the autocrine function of VEGFA may be uniquely associated with prostate cancer. Activation of VEGFR-2 by VEGFA(165) was shown to enhance migration of PC3 cells. A similar effect was also observed with endogenous VEGFA induced by TGF-beta1 and hypoxia. These findings illustrate that an autocrine loop of VEGFA via VEGFR-2 is critical for the tumorigenic effects of TGF-beta1 and hypoxia on metastatic prostate cancers.

Although the potential roles of endothelial cells in the microvascules of prostate cancer during angiogenesis have been documented, their direct impacts on the prostate cancer metastasis remain unclear. We found that the CD31-positive and CD34-positive endothelial cells are increased in prostate cancer compared with the normal tissues and that these endothelial cells were decreased upon castration, gradually recovered with time, and increased after prostate cancer progressed into the castration-resistant stage, suggesting a potential linkage of these endothelial cells with androgen deprivation therapy. The in vitro invasion assays showed that the coculture of endothelial cells with prostate cancer cells significantly enhanced the invasion ability of the prostate cancer cells. Mechanism dissection found that coculture of prostate cancer cells with endothelial cells led to increased interleukin (IL)-6 secretion from endothelial cells, which may result in downregulation of androgen receptor (AR) signaling in prostate cancer cells and then the activation of TGF-beta/matrix metalloproteinase-9 (MMP-9) signaling. The consequences of the IL-6-->AR-->TGFbeta-->MMP-9 signaling pathway might then trigger the increased invasion of prostate cancer cells. Blocking the IL-6-->AR-->TGFbeta-->MMP-9 signaling pathway either by IL-6 antibody, AR-siRNA, or TGF-beta1 inhibitor all interrupted the ability of endothelial cells to influence prostate cancer invasion. These results, for the first time, revealed the important roles of endothelial cells within the prostate cancer microenvironment to promote the prostate cancer metastasis and provide new potential targets of IL-6-->AR-->TGFbeta-->MMP-9 signals to battle the prostate cancer metastasis.

In developed countries, prostate cancer (PC) is the neoplasia more frequently diagnosed in men. The signaling pathway induced by the transforming growth factor beta1 (TGFbeta1) has an important role in cell growth, differentiation, and development, the downregulation of this pathway being associated with cancer development. In PC, the activation of this signaling pathway is lost, resulting in favoring of tumor growth, proliferation, and evasion of apoptosis. Several studies have shown that microRNAs (miRNAs), small non-coding RNA, are closely associated with the development, invasion, and metastasis, suggesting that they have a critical role in cancer development. Recently, Smad proteins, the signal transducers of the TGFbeta1 signaling pathway, were found to regulate miRNA expression, through both transcriptional and posttranscriptional mechanisms. In this review, we summarize the mechanisms underlying Smad-mediated regulation of miRNA biogenesis and the effects on cancer development, particularly in PC. We identify that TGFbeta1-related miR-143, miR-145, miR-146a, and miR-199a may have a key role in the development of prostate cancer metastasis and the restoration of their expression may be a promising therapeutic strategy for PC treatment.

OBJECTIVE: To study the expression of transforming growth factor-beta1 (TGF-beta1) and E-cadherin (E-cd) in Supraglottic larynx squamous cell carcinoma (SGLSCC) and the correlation with lymph node metastasis of neck. METHOD: The expression of TGF-beta1 and E-cd were studied in 60 cases of samples with SGLSCC and 10 cases of normal laryngeal mucosa by immunohistochemical staining (SABC method). They connected with clinical and followed data were analyzed. RESULT: Among 60 cases of human SGLSCC, 81.7% (49/60), 70.0% (42/60) were respectively defined as TGF-beta1 and E-cd - positive. Among 10 cases of normal laryngeal mucosa, 20.0% (2/10) 90.0% (9/10) were respectively defined as TGF-beta1 and E-cd - positive. There is a positive correlation between the expression of TGF-beta1 and the groups of lymph node metastasis, pathologic grade and clinical stage. However, there is a negative correlation between the expression of E-cd and the groups of lymph node metastasis, pathologic grade and clinical stage. The expression of the two indexes were significantly related to lymph node metastasis and not related to the age and sex of the patients,as well as the size of tumors. Although the two indexes were not concerted, they were inversely correlated with each other. E-cd expression was directly correlated with the survival functions of operated patients. CONCLUSION: The expression of TGF-beta1 and E-cd are correlated with lymph node metastasis in SGLSCC. There was negatively related to the two indexes. The two indexes may become the marker to predict the lymph node metastasis in SGLSCC, and E-cd may become the marker to judge the prognosis of SGLSCC.