1490

CTGF

connective tissue growth factor;CTGF;connective tissue growth factor

CCN family member 2|IBP-8|IGF-binding protein 8|IGFBP-8|hypertrophic chondrocyte-specific protein 24|insulin-like growth factor-binding protein 8

6q23.1

protein-coding

The role of CTGF/CCN2 in osteolytic metastasis by breast cancer cells and its mechanism of action were studied. Osteolytic metastasis accompanied by CCN2 and PTHrP overproduction was efficiently inhibited by an anti-CCN2 antibody. Furthermore, we found that CCN2 was induced by PTHrP through PKA-, PKC-, and ERK-mediated pathways therein. INTRODUCTION: Connective tissue growth factor (CTGF/CCN2) is a mediator of local angiogenesis induced by breast cancer, but its role in osteolytic metastasis has not been evaluated. PTH-related peptide (PTHrP) is another critical factor in the development of the osteolytic metastasis. Using both in vivo and in vitro approaches, we studied whether/how neutralization of CCN2 prevented bone metastasis and how PTHrP signaling is related. MATERIALS AND METHODS: A mouse model of bone metastasis by human breast cancer cell line MDA231 was treated with a CCN2-neutralizing antibody, and osteolytic bone metastases were assessed on radiographs and immunohistochemistry. Ccn2 gene expression and transcription were examined by Northern blot and luciferase analysis. Immunoblot analysis and kinase inhibitors were used to identify the signaling pathways implicated. Anti-angiogenic/osteoclastogenic effects of ccn2 downregulation were also evaluated. RESULTS: Treatment of mice with a CCN2-neutralizing antibody greatly decreased osteolytic bone metastasis, microvasculature, and osteoclasts involved. The antibody also suppressed the growth of subcutaneous tumor in vivo and proliferation and migration of human umbilical vein endothelial cells (HUVECs) in vitro. Downregulation of ccn2 also repressed osteoclastogenesis. CCN2 expression was specifically observed in cancer cells producing PTHrP and type I PTH/PTHrP receptor (PTH1R) invaded the bone marrow, and PTHrP strongly upregulated ccn2 in MDA231 cells in vitro. Activation of protein kinase C (PKC) and protein kinase A (PKA) was necessary and sufficient for the stimulation of ccn2 by PTHrP. Indeed, inhibition of the extracellular signal-regulated kinase (ERK1/2), PKC, or PKA by specific inhibitors counteracted the stimulation of ccn2 expression. Incubation of MDA231 cells with PTHrP induced the activation of ERK1/2. Consistent with these findings, inhibition of PKC prevented PTHrP-induced ERK1/2 activation, whereas 12-O-tetradecanoylphorbol13-acetate (TPA), a stimulator of PKC, upregulated it. CONCLUSIONS: CCN2 was critically involved in osteolytic metastasis and was induced by PKA- and PKC-dependent activation of ERK1/2 signaling by PTHrP. Thus, CCN2 may be a new molecular target for anti-osteolytic therapy to shut off the PTHrP-CCN2 signaling pathway.

Connective tissue growth factor (CTGF) is believed to be a multifunctional signaling modulator involved in a wide variety of biological or pathological processes including carcinogenesis. The role of CTGF in gastric cancer (GC) has not been reported so far. In the present study the expression of CTGF, vascular endothelial growth factor (VEGF), VEGF-C and VEGF-D on immunohistochemistry in GC and the correlation between the expression of CTGF and VEGF, VEGF-C, VEGF-D were examined, along with the correlation between the expression of CTGF and clinicopathological parameters, as well as survival of the patients with GC. The expression of CTGF was significantly in agreement with expression of VEGF, VEGF-C and VEGF-D (kappa and P, respectively: 0.538, P < 0.001; 0.502, P < 0.001; 0.558, P < 0.001). High CTGF expression was significantly associated with lymph nodes metastasis (P = 0.038) and lower postoperative 5 year overall survival rates (23.9%) compared with those patients with low CTGF expression (48.4%, P = 0.0035). The present findings suggest that CTGF is a useful prognostic marker for GC. High CTGF expression is associated with the risk of lymph nodes metastasis and a poor survival time in GC.

OBJECTIVE: To study the expressions of CTGF and OPN and detect their clinical value and correlation in the laryngeal squamous cell carcinoma tissues and paracancerous tissues. METHOD: SP immunohistochemical method was used for the assays of CTGF and OPN on the routinely paraffin-embedded sections of surgical operated specimens of 41 cases with laryngeal squamous cell carcinoma and 20 ones with paracancerous tissues. RESULT: The positive rate of CTGF and the score were significantly lower in cancer tissues than those in paracancerous tissues (61.0% vs 90.0%, P < 0.05; 2.41 +/- 1.60 vs 4.24 +/- 1.42, P < 0.01), but those of OPN were opposite (61.0% vs 15.0%, P < 0.01; 3. 10 +/- 1.63 vs 1.12 +/- 0.84, P < 0.01). The positive rates and scores of CTGF were significantly higher in the cases without-metastasis of lymph node and clinical stage T1 than those in the ones with-metastasis of lymph node and clinical stage T3 (P < 0.01) . The positive rates and scores of OPN were significantly lower in the cases without-metastasis of lymph node, clinical stage T1 and histological grade I those that in the ones with-metastasis of lymph node, Clinical stage T3 and histological grade III (P < 0.01). The closely negative correlation was found between the score of CTGF and that of OPN. CONCLUSION: The expression of CTGF and/or OPN might be important biological markers in reflecting the progression, biological behaviors, metastatic potential and prognosis of the laryngeal squamous cell carcinoma.

AIM: To investigate the expression of cysteine-rich61 (Cyr61), connective tissue growth factor (CTGF) and nephroblastoma overexpressed gene (Nov) in hepatocellular carcinoma (HCC), and to evaluate the relationship between Cyr61, CTGF and Nov genes expression with invasion and metastasis of HCC. METHODS: Thirty-one HCC specimens were divided into small hepatocellular carcinoma (SHCC), nodular hepatocellular carcinoma (NHCC), solitary large hepatocellular carcinoma (SLHCC) according to their diameter and number of nodes. Reverse transcription polymerse chain reaction (RT-PCR) was used to detect the mRNA expression levels of Cyr61, CTGF and Nov genes in 31 resected specimens of hepatocellular carcinoma and para-cancerous normal liver tissues semi-quantitatively and the relation between their expression levels and clinical pathological parameters were compared. RESULTS: The expressions of Cyr61 and CTGF mRNA in carcinoma tissues were significantly higher than those in para-cancerous normal liver tissues (P<0.01). The expressions of Cyr61 and CTGF mRNA in HCC with venous invasion were higher than those in HCC without venous invasion. CTGF expression in HCC Edmondson's grade III-IV was significantly higher than that in HCC Edmondson's grade I-II (P = 0.022). There was no obvious correlation between Nov mRNA and clinical-pathological features. Compared to NHCC, SLHCC had better cell differentiation, easier capsule formation, less microscopic venous invasion, milder liver cirrhosis. The expressions of Cyr61 and CTGF mRNA in NHCC were significantly higher than those in SLHCC and SHCC. CONCLUSION: Cyr61 and CTGF genes may play an important role in hepatocellular carcinogenesis and correlate with recurrence and metastasis of hepatocellular carcinoma. SLHCC has better biological behaviors than NHCC.

PURPOSE: The biology underlying bone-specific metastasis (BM) of hepatocellular carcinoma (HCC) is poorly understood. The goal of the present study is to further elucidate the molecular and cellular mechanisms underlying HCC with BM. METHODS: The expression of connective tissue growth factor (CTGF) and interleukin-11 (IL-11) in RNA extracted from 127 formalin-fixed, paraffin-embedded HCC specimens was examined by quantitative real-time polymerase chain reaction. A cellular hypoxic model was established in vitro to investigate CTGF and osteoprotegerin (OPG) expression and roles in hypoxia-induced tumor aggressiveness. RESULTS: The mean CTGF expression in BM versus non-metastatic samples was 3.63-times higher, and IL-11 expression was detected in 62.5 % (10/16) of BM samples versus only in 18.9 % (21/111) of the non-metastatic ones. Highly metastatic HCC cell lines tended to show strong expression of CTGF and IL-11, but low expression of OPG. Hypoxic stimulation of HCC 97L cells increased the level of CTGF mRNA by 2.80-fold within 1.5 h, and hypoxia-inducible factor-1alpha mRNA levels in these cells could be increased by stimulation with recombinant CTGF protein. Furthermore, OPG and matrix metalloproteinase-2 and -9 levels were also induced under hypoxic conditions. CONCLUSIONS: expression levels of intratumoral CTGF or IL-11 were independent prognostic factors for the development of BM in HCC patients. tumor hypoxia enhanced the expression of CTGF, which initiates the invasive angiogenesis cascade and enhances expression of many hypoxia-associated genes. Cellular release of OPG may play a role in tumor cell survival. The hypoxia-induced cascade in HCC cells may contribute to invasion and metastasis in vivo.

AIM: To determine the expression characteristics of connective tissue growth factor (CTGF/CCN2) in human hepatocellular carcinoma (HCC) in histology and to elucidate the roles of CCN2 on hepatoma cell cycle progression and metastasis in vitro. METHODS: Liver samples from 36 patients (who underwent hepatic resection for the first HCC between 2006 and 2011) and 6 normal individuals were examined for transforming growth factor beta1 (TGF-beta1) or CCN2 mRNA by in situ hybridization. Computer image analysis was performed to measure integrated optimal density of CCN2 mRNA-positive cells in carcinoma foci and the surrounding stroma. Fibroblast-specific protein-1 (FSP-1) and E-cadherin were examined to evaluate the process of epithelial to mesenchymal transition, alpha-smooth muscle actin and FSP-1 were detected to identify hepatic stellate cells, and CD34 was measured to evaluate the extent of vascularization in liver tissues by immunohistochemical staining. CCN2 was assessed for its stimulation of HepG2 cell migration and invasion using commercial kits while flow cytometry was used to determine CCN2 effects on HepG2 cell-cycle. RESULTS: In situ hybridization analysis showed that TGF-beta1 mRNA was mainly detected in connective tissues and vasculature around carcinoma foci. In comparison to normal controls, CCN2 mRNA was enhanced 1.9-fold in carcinoma foci (12.36 +/- 6.08 vs 6.42 +/- 2.35) or 9.4-fold in the surrounding stroma (60.27 +/- 28.71 vs 6.42 +/- 2.35), with concomitant expression of CCN2 and TGF-beta1 mRNA in those areas. Epithelial-mesenchymal transition phenotype related with CCN2 was detected in 12/36 (33.3%) of HCC liver samples at the edges between carcinoma foci and vasculature. Incubation of HepG2 cells with CCN2 (100 ng/mL) resulted in more of the cells transitioning into S phase (23.85 +/- 2.35 vs 10.94 +/- 0.23), and induced a significant migratory (4.0-fold) and invasive (5.7-fold) effect. TGF-beta1-induced cell invasion was abrogated by a neutralizing CCN2 antibody showing that CCN2 is a downstream mediator of TGF-beta1-induced hepatoma cell invasion. CONCLUSION: These data support a role for CCN2 in the growth and metastasis of HCC and highlight CCN2 as a potential novel therapeutic target.

BACKGROUND: tumor invasion and metastasis cause most deaths in cancer patients. Connective tissue growth factor (CTGF), a secreted protein that binds to integrins, modulates the invasive behavior of certain human cancer cells, but few mechanistic details are known. We investigated the roles of CTGF and collapsin response mediator protein 1 (CRMP-1) in metastasis and invasion of human lung adenocarcinoma. METHODS: We compared vector control-transfected cells with corresponding CTGF gene-transfected cells. Invasive activity was measured with a modified Boyden chamber assay, and metastatic activity was measured in an animal model. We used CTGF deletion mutants, CTGF and CRMP-1 antisense oligonucleotides, and anti-integrin and anti-CRMP-1 antibodies to investigate the functional relationship between CTGF and CRMP-1. expression of CTGF protein in 78 lung adenocarcinoma specimens was investigated immunohistochemically. All statistical tests were two-sided. RESULTS: Invasive (both P<.001) and metastatic (P<.001 and P=.003, respectively) activities were lower in cells that overexpress CTGF than in vector control cells. expression of CRMP-1 was higher in CTGF-transfected clones than in vector control cells, and its level decreased after cells were treated with anti-integrin alpha(v)beta3 and alpha(v)beta5 antibodies. Reduced levels of CRMP-1 protein after the transfection of CRMP-1-specific antisense oligonucleotides, but not sense oligonucleotides, increased the invasiveness of CTGF-transfected cells (mean numbers of invasive CTGF-transfected cells treated with 20 microM CRMP-1-specific sense and antisense oligonucleotides were 327 and 516 cells, respectively [difference = 189 cells, 95% confidence interval [CI] = 156 to 221 cells; P<.001]). The CT module of CTGF was the region primarily responsible for the increased expression of CRMP-1 and the inhibition of invasion (mean numbers of invasive cells expressing full-length CTGF and CT module-deleted mutant were 148 and 385 cells, respectively [difference = 237 cells, 95%

Connective tissue growth factor (CTGF) plays an important role in fibrosis by modulating cell migration and cell growth but may also modify tumor growth and metastasis. Because CTGF is overexpressed in pancreatic ductal adenocarcinoma, we investigated the in vitro effects of CTGF on the proliferation and invasiveness of PANC-1 pancreatic cancer cells and examined the consequences of its in vivo inhibition on the growth and metastasis of these cells using a fully human CTGF-specific monoclonal antibody (FG-3019) in an orthotopic nude mouse model. Although PANC-1 cells expressed relatively high levels of endogenous CTGF mRNA, the addition of CTGF to conditioned medium increased the proliferation and invasiveness of PANC-1 cells. Moreover, transforming growth factor-beta1 caused a further increase in CTGF expression in these cells. In vivo, the twice weekly i.p. administration of FG-3019 decreased tumor growth and metastasis and attenuated tumor angiogenesis and cancer cell proliferation. FG-3019 did not enhance apoptosis and did not attenuate the inhibitory effects of gemcitabine on tumor growth and metastasis. These findings suggest that CTGF may contribute to aberrant autocrine and paracrine pathways that promote pancreatic cancer cell growth, invasion, metastasis, and angiogenesis. Therefore, blocking CTGF actions with FG-3019 may represent a novel therapeutic approach in pancreatic ductal adenocarcinoma.