2932

GSK3B

Accumulating evidence indicates that hyperactive Wnt signalling occurs in association with the development and progression of human breast cancer. As a consequence of engaging the canonical Wnt pathway, a beta-catenin-T-cell factor (TCF) transcriptional complex is generated, which has been postulated to trigger the epithelial-mesenchymal transition (EMT) that characterizes the tissue-invasive phenotype. However, the molecular mechanisms by which the beta-catenin-TCF complex induces EMT-like programmes remain undefined. Here, we demonstrate that canonical Wnt signalling engages tumour cell dedifferentiation and tissue-invasive activity through an Axin2-dependent pathway that stabilizes the Snail1 zinc-transcription factor, a key regulator of normal and neoplastic EMT programmes. Axin2 regulates EMT by acting as a nucleocytoplasmic chaperone for GSK3beta, the dominant kinase responsible for controlling Snail1 protein turnover and activity. As dysregulated Wnt signalling marks a diverse array of cancerous tissue types, the identification of a beta-catenin-TCF-regulated Axin2-GSK3beta-Snail1 axis provides new mechanistic insights into cancer-associated EMT programmes.

Acquisition of resistance to tamoxifen is a critical therapeutic problem in breast cancer patients. epithelial-mesenchymal transition (EMT), where cells undergo a developmental switch from a polarized epithelial phenotype to a highly motile mesenchymal phenotype, is associated with invasion and motility of cancer cells. Here, we found that tamoxifen-resistant (TAMR)-MCF-7 cells had undergone EMT, as evidenced by mesenchymal-like cell shape, downregulation of basal E-cadherin expression, and overexpression of N-cadherin and vimentin, as well as increased Snail transcriptional activity and protein expression. Given the roles of glycogen synthase kinase (GSK)-3beta and nuclear factor (NF)-kappaB in Snail-mediated E-cadherin deregulation during EMT, we examined the role of these signaling pathways in the EMT of TAMR-MCF-7 cells. Both Ser9-phosphorylated GSK-3beta (inactive form) and NF-kappaB reporter activity were increased in TAMR-MCF-7 cells, as was activation of the phosphatase and tensin homolog depleted on chromosome ten (PTEN)-phosphoinositide 3 (PI3)-kinase-Akt pathway. Pin1, a peptidyl-prolyl isomerase, was overexpressed in TAMR-MCF-7 cells, and Snail transcription and the expression of EMT markers could be decreased by Pin1 siRNA treatment. These results imply that Pin1 overexpression in TAMR-MCF-7 cells is involved in the EMT process via PTEN-PI3-kinase-Akt-GSK-3beta and/or GSK-3beta-NF-kappaB-dependent Snail activation, and suggest the potential involvement of Pin1 in EMT during breast cancer development.

OBJECTIVE: To investigate the role of phosphorylation of glycogen synthase kinase-3beta (GSK-3beta) inducing epithelial mesenchymal transition in human peritoneal mesothelial cells (HPMC). METHODS: Primary HPMC was harvested from human omental tissue and maintained under defined in vitro conditions. The expression of p-GSK-3beta and total GSK-3beta in HMPC was detected by Western blot after incubation with different concentrations (0, 5, 10, 20, and 40 mmol/L)of LiCl at different time points (0, 1, 3, 6, and 12 h). The protein expression of E-cadherin and alpha-SMA was also examined after treatment with 20 mmol/L LiCl according to different time courses. The intracellular distribution and expression of alpha-SMA were determined by indirect immunofluorescence. RESULTS: LiCl stimulated phosphorylation of GSK-3beta and the effect was time-dependent and concentration-dependent to limited extent (P<0.05). The expression of alpha-SMA increased (P<0.05) and the expression of E-cadherin decreased significantly (P<0.05) after 24 h stimulation by 20 mmol/L LiCl. The indirect immunoflurescence showed that the expression of alpha-SMA in HPMC increased significantly after 24 h incubation with 20 mmol/L LiCl. CONCLUSION: The phosphorylation of GSK-3beta leads HMPC to epithelial mesenchymal transition and provides new clue for the treatment of peritoneal fibrosis.

Glycogen synthase kinase 3 beta (GSK3beta) is highly inactivated in epithelial cancers and is known to inhibit tumor migration and invasion. The zinc-finger-containing transcriptional repressor, Slug, represses E-cadherin transcription and enhances epithelial-mesenchymal transition (EMT). In this study, we find that the GSK3beta-pSer9 level is associated with the expression of Slug in non-small cell lung cancer. GSK3beta-mediated phosphorylation of Slug facilitates Slug protein turnover. Proteomic analysis reveals that the carboxyl terminus of Hsc70-interacting protein (CHIP) interacts with wild-type Slug (wtSlug). Knockdown of CHIP stabilizes the wtSlug protein and reduces Slug ubiquitylation and degradation. In contrast, nonphosphorylatable Slug-4SA is not degraded by CHIP. The accumulation of nondegradable Slug may further lead to the repression of E-cadherin expression and promote cancer cell migration, invasion and metastasis. Our findings provide evidence of a de novo GSK3beta-CHIP-Slug pathway that may be involved in the progression of metastasis in lung cancer.

Chemokine (C-C motif) ligand 18 (CCL18), which is derived from tumour-associated macrophages (TAMs), plays a critical role in promoting breast cancer metastasis via its receptor, PYK2 N-terminal domain interacting receptor 1 (Nir1). However, the molecular mechanism by which Nir1 promotes breast cancer metastasis by binding to CCL18 remains elusive. In this study, Nir1 expression was associated with lymph node and distant metastasis in patients with invasive ductal carcinoma. For the first time, we report that Nir1 binding to CCL18 promotes the phosphorylation of Akt, LIN-11, Isl1 and MEC-3 protein domain kinase (LIMK), and cofilin, which is a critical step in cofilin recycling and actin polymerisation. Interestingly, Nir1 binding to CCL18 can enhance cell mesenchymal properties and induce epithelial-mesenchymal transition (EMT). Mechanistically, Nir1 binding to CCL18 stabilises Snail via the Akt/GSK3beta signalling pathway. In support of these observations, Nir1 binding to CCL18 promoted lung metastasis and LY294002 could inhibit it in vivo. In summary, our in vitro and in vivo results indicate that Nir1 binding to CCL18 plays an important role in breast cancer invasion/metastasis. This study identified both Nir1 and CCL18 as potential anti-invasion targets for therapeutic intervention in breast cancer.CI - Copyright (c) 2013 Elsevier Ltd. All rights reserved.

Radiotherapy is an effective treatment method for lung cancer, particularly when the disease is at an advanced stage. However, previous researchers have observed that the majority of patients with conventional radiation therapy develop distant metastases and succumb to the disease. Thus, identifying and understanding novel pathways for the development of new therapeutic targets is a major goal in research on pulmonary neoplasms. Recent studies suggest that epithelial-mesenchymal transition (EMT) is the most important contributor to cancer metastasis. Induction of this complex process requires endogenously produced microRNAs; specifically, downregulation of the miRNA-200c causes an induction of EMT. We recently identified the tank-binding kinase-1 (TBK1) as a downstream effector of the miR-200c-driven pathway, but the biological function of TBK1 in EMT remains unknown. In this study, we tested whether TBK1 has a role in radiation-induced EMT and identified associated potential mechanisms. Human alveolar type II epithelial carcinoma A549 cells were irradiated with (60)Co gamma-rays. Western blotting revealed a time- and dose-dependent decrease in E-cadherin with a concomitant increase in vimentin after radiation, suggesting that the epithelial cells acquired a mesenchymal-like morphology. TBK1 siRNA significantly inhibited radiation-induced suppression of the epithelial marker E-cadherin and upregulation of the mesenchymal marker vimentin. The invasion and migratory potential of lung cancer cells upon radiation treatment was also reduced by TBK1 knockdown. Furthermore, radiation-induced EMT attenuated by TBK1 depletion was partially dependent on transcriptional factor ZEB1 expression. Finally, we found glycogen synthase kinase-3beta (GSK-3beta) is involved in regulation of radiation-induced EMT by TBK1. Thus, our findings reveal that TBK1 signaling regulates radiation-induced EMT by controlling GSK-3beta phosphorylation and ZEB1 expression. TBK1 may therefore constitute a useful target for treatment of radiotherapy-induced metastasis diseases.

BACKGROUND: epithelial-mesenchymal transition (EMT) plays a pivotal role in the development of metastatic cancers. Basic fibroblast growth factor (bFGF) is significantly elevated in metastatic prostate cancers, which has been mentioned mainly to induce EMT in normal cells. However, there is no description about bFGF induced EMT and its underlying mechanism in prostate cancer cells. METHODS: Western blotting, immunofluorescence and qRT-PCR assays were used to study protein or mRNA expression profiles of the EMT. Wound healing scratch, migration and invasion assays were used to test the motility of cells undergoing EMT. More methods were used to explore the underlying mechanisms. RESULTS: We demonstrated that bFGF promoted EMT and motility of human prostate cancer PC-3 cells. Both protein and mRNA expression of Snail were rapidly increased after bFGF treatment. Ectopic expression of Snail triggered EMT and enhanced cell motility in PC-3 cells, and knockdown of Snail almost abolished bFGF induced EMT, suggesting the critical role of Snail. Mechanistic study demonstrated that bFGF promoted the stability, nuclear localization and transcription of Snail by inhibiting the activity of glycogen synthase kinase 3 beta (GSK-3beta) through phosphatidylinositide 3 kinases (PI3K)/protein kinase B (AKT) signaling pathway. CONCLUSIONS: It is concluded that bFGF can promote EMT and motility of PC-3 cells, and AKT/GSK-3beta signaling pathway controls the stability, localization and transcription of Snail which is crucial for this bFGF induced EMT. GENERAL SIGNIFICANCE: To our knowledge, this is the first study to demonstrate that bFGF can induce EMT via AKT/GSK-3beta/Snail signaling pathway in prostate cancer cells.CI - Copyright (c) 2014 Elsevier B.V. All rights reserved.

cancer metastasis is considered a major challenge in cancer therapy. Recently, epidermal growth factor (EGF)/epidermal growth factor receptor (EGFR) signaling has been shown to induce epithelial-mesenchymal transition (EMT) and thereby to promote cancer metastasis. However, the underlying mechanism has not been fully elucidated. We demonstrate that EGF can induce EMT in human prostate and lung cancer cells and thus promote invasion and migration. EGF-induced EMT has been characterized by the cells acquiring mesenchymal spindle-like morphology and increasing their expression of N-cadherin and fibronectin, with a concomitant decrease of E-cadherin. Both protein and mRNA expression of transcription factor Snail rapidly increases after EGF treatment. The knockdown of Snail significantly attenuates EGF-induced EMT, suggesting that Snail is crucial for this process. To determine the way that Snail is accumulated, we demonstrate (1) that EGF promotes the stability of Snail via inhibiting the activity of glycogen synthase kinase 3 beta (GSK-3beta), (2) that protein kinase C (PKC) rather than the phosphatidylinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway is responsible for GSK-3beta inhibition and (3) that GSK-3beta inhibition promotes the transcription of Snail. Taken together, these results reveal that the PKC/GSK-3beta signaling pathway controls both the stability and transcription of Snail, which is crucial for EMT induced by EGF in PC-3 and A549 cells. Our study suggests a novel signaling pathway for Snail regulation and provides a better understanding of growth-factor-induced tumor EMT and metastasis.

Protocadherin 9 (PCDH9) was found frequently lost in hepatocellular carcinoma (HCC). Here we investigated the role of PCDH9 in the development of HCC. We confirmed that PCDH9 was down-regulated in HCC tissues and cell lines compared with the adjacent non-tumor tissues. PCDH9 downregulation was significantly associated with malignant portal vein invasion of HCC patients. Gain- and loss-of-function studies revealed that downregulation of PCDH9 facilitated tumor cell migration and epithelial-mesenchymal transition (EMT). We identified PCDH9 as a novel regulator of EMT by increasing the activity of GSK-3beta and inhibiting Snail1, indicating its potential therapeutic value for reducing metastasis of HCC.CI - Copyright (c) 2014 The Authors. Published by Elsevier Inc. All rights reserved.

epithelial to mesenchymal transition (EMT) has received considerable attention as a conceptual paradigm for explaining the invasive and metastatic behavior of cells during cancer progression. Our previous study showed that loss of expression of TSSC3 is positively associated with osteosarcoma malignancy and progression. However, whether TSSC3 mediates EMT in osteosarcoma is poorly understood. In the present study, we determined that TSSC3 downregulation induced cell migration and invasion ability and promoted mesenchymal transition of osteosarcoma cells by upregulating mesenchymal markers and inhibiting the epithelial markers. Furthermore, TSSC3 downregulation elicited a signaling cascade that included increased levels of Wnt3a and LRP5, inactivation of GSK-3beta, accumulation of nuclear beta-catenin and Snail, the augmented binding of beta-catenin to TCF-4, and accordingly increased the expression of Wnt target genes (CD44, MMP7). The gene knockdown of these signaling proteins could inhibit TSSC3 downregulation-promoted EMT, migration, and invasion in osteosarcoma. Finally, TSSC3 overexpression obviously inhibited cell migration, invasion, and repressed mesenchymal phenotypes, reducing lung metastasis through GSK-3beta activation. Collectively, TSSC3 downregulation promotes the EMT of osteosarcoma cells by regulating EMT markers via a signal transduction pathway that involves Snail, Wnt-beta-catenin/TCF, and GSK-3beta.CI - Copyright (c) 2016 Elsevier Ireland Ltd. All rights reserved.

Hepatocellular carcinoma progression is thought to be driven by cancer stem cells (CSCs). No clinical trial has, as yet, shown convincing long-term disease free survival results for the majority of patients in HCC. So it is important to discover new anti-cancer agents. In our study, we chose sophocarpine, which is derived from the foxtail-like sophora herb, for its efficacy to inhibit HCC including CSCs and potential mechanism study. Our results show that sophocarpine could not only reduce HCC cell viability, eliminate HCC and reverse hepatoma cells malignant phenotype, but also reduce the ratio of CSCs and inhibit the sphere formation of CSCs in vitro. In vivo, sophocarpine significantly displayed antitumor effects in subcutaneous xenograft HCC models and orthotopic transplantation tumor models. Further studies showed that sophocarpine could exert anti-tumor effects partly via downregulating the activity of the cancer stem cell related pathways and inhibiting EMT induced by TGF-beta.CI - Copyright (c) 2016 Elsevier Ireland Ltd. All rights reserved.

epithelial-mesenchymal transition (EMT) plays an important role in metastasis of gastric cancer. Our previous study showed that Gastrokine-2 (GKN2) can inhibit the metastasis of SGC-7901 and AGS cells. Herein, we further explored the role of GKN2 in epithelial mesenchymal transition of gastric cancer cells and the underlying mechanisms. We found that overexpression of GKN2 can lower the protein expression level of Snail and markedly elevate E-cadherin protein level in SGC7901 and AGS cells. Further data showed that knockdown of snail can inhibit the migration and invasion of SGC-7901 and AGS cells. It is known that Snail can be phosphorylated by GSK3beta, a downstream protein of PI3K/AKT pathway. We then test protein expression of p-GSK3beta(Ser-9), the downstream protein of PI3K/AKT, which was significantly decreased under the circumstance of GKN2 overexpression. Moreover, LY294002, a PI3K inhibitor, can reverse the protein expression change of E-cadherin and snail induced by siGKN2. Taken together, these findings suggested that GKN2 suppressed epithelial mesenchymal transition of gastric cancer cells by downregulation of snail through PI3K/AKT/GSK3beta signaling pathway.

Cholangiocarcinoma (CCA) invasion and metastasis are the primary causes of poor survival rates in patients. The epithelial-mesenchymal transition (EMT) is a crucial step in cancer invasion and metastasis. However, it is still unclear of the molecular mechanism. In this study, the expression of 14-3-3zeta and atypical protein kinase C-iota (aPKC-iota) was further detected in CCA tissues and cell lines. Meanwhile, we established the EMT model of CCA cells and investigated 14-3-3zeta and aPKC-iota co-regulatory effect on the EMT in vitro and in vivo. Further, we identified the downstream molecular glycogen synthase kinase 3 beta (GSK-3beta)/Snail signalling pathway that contribute to regulating the EMT. Our data showed that the expression of 14-3-3zeta and aPKC-iota was synergistically increased in CCA tissues compared with adjacent noncancerous tissues and was intimately associated with differentiation and the tumour-node-metastasis (TNM) stage. Multivariate Cox regression analysis indicated that high 14-3-3zeta and aPKC-iota expression separately predicted a poor prognosis and were independent prognostic indicators in patients with CCA. The CO-IP experiment confirmed that the mutual binding relationship between 14-3-3zeta and aPKC-iota. Small interfering RNAs and siRNA rescue experiment demonstrated that 14-3-3zeta and aPKC-iota regulated each other. In addition, 14-3-3zeta and aPKC-iota pretreatment by si-RNA inhibit the phosphorylated GSK-3beta and Snail expression during EMT. Meanwhile, silence of 14-3-3zeta or aPKC-iota suppressed CCA cells migration, metastasis and proliferation in vitro and in vivo. Our study demonstrates that 14-3-3zeta and aPKC-iota synergistically facilitate EMT of CCA via GSK-3beta/Snail signalling pathway, and may be potential therapeutic target for CCA.

Metastasis is the major cause of treatment failure in anaplastic thyroid carcinoma (ATC) patients. In the preliminary study, we demonstrated that interleukin (IL)-11 expression is positively correlated with distant metastasis in ATC. However, the mechanisms underlying remain largely unknown. Here, we found that cobalt chloride (a hypoxia mimetic) promoted IL-11 expression via HIF-1alpha activation. Furthermore, the resultant increase in IL-11 expression significantly induced epithelial-mesenchymal transition (EMT) in ATC cells, accompanied by Akt/GSK3beta pathway activation and increased invasive and migratory abilities. Conversely, HIF-1alpha or IL-11 knockdown, or treating cells with a neutralizing antibody against IL-11, a PI3K inhibitor, or Akt inhibitor V, significantly suppressed the induction of EMT and counteracted the enhancements in invasive and migratory abilities. These results indicate that hypoxia increases IL-11 secretion in ATC cells via HIF-1alpha induction and that IL-11 then induces EMT in these cells via the PI3K/Akt/GSK3beta pathway, ultimately improving their invasive and migratory potential. This study elucidates the prometastatic role played by IL-11 in ATC metastasis and indicates it as a potential target for the treatment of cancer metastasis. However, many questions remain to be explored.

Recently, beta-arrestin1 was indicated as a tumor promoter in prostate cancer, but its exact role in cancer metastasis still have not been well clarified. Here, our data revealed that beta-arrestin1 could promote the migration and invasion of prostate cancer cells via initiating epithelial-mesenchymal transition (EMT). Mechanically, beta-arrestin1 could increase the transcriptional activity and expression of beta-catenin, together with Akt activity, whereas decrease the activities of GSK-3beta and PP2A. In addition, beta-arrestin1 could function as a scaffold protein in modulating the interactions between PP2A, Akt, GSK-3beta and beta-catenin. These results reveal a novel mechanism of beta-arrestin1 in modulating EMT and GSK-3beta/beta-catenin signaling in prostate cancer, thereby suggest that assessment of beta-arrestin1 may provide a potential therapeutic target for prostate cancer.CI - Copyright (c) 2016 Elsevier Inc. All rights reserved.

epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy. Despite the anticancer capabilities of emodin observed in many cancers, including EOC, the underlying molecular mechanism remains to be elucidated. A crucial link has been discovered between the acquisition of metastatic traits and the epithelial-mesenchymal transition (EMT). The present study aimed to determine whether emodin could inhibit the EMT of EOC cells and explore the underlying mechanism. The CCK-8 assay and transwell assay showed that emodin effectively repressed the abilities of proliferation, invasion, and migration in A2780 and SK-OV-3 cells. The Western blot showed that emodin upregulated epithelial markers (E-cadherin and Claudin) while it downregulated mesenchymal markers (N-cadherin and Vimentin) and transcription factor (Slug) in a dose-dependent fashion. After transfection of siRNA-Slug, both Slug and N-cadherin were downregulated in EOC cells while E-cadherin was upregulated, which was intensified by emodin. Besides, emodin decreased the expression of ILK, p-GSK-3beta, beta-catenin, and Slug. Transfection of siRNA-ILK also achieved the same effects, which was further strengthened by following emodin treatment. Nevertheless, SB216763, an inhibitor of GSK-3beta, could reverse the effects of emodin except for ILK expression. These findings suggest that emodin inhibited the EMT of EOC cells via ILK/GSK-3beta/Slug signaling pathway.

While TGF-beta1 is known to induce epithelial-mesenchymal transition (EMT), a major factor in the pathogenesis of proliferative vitreoretinopathy (PVR), in ARPE-19 cells. The molecular pathways involved in EMT formation have not yet to be fully characterized. In this study, we have found that TGF-beta1-mediated induction of EMT in ARPE-19 cells varied in a dose- and time-dependent manner. Specifically, TGF-beta1 inhibited GSK-3beta by accelerating phosphorylation at ser9. GSK-3beta inhibitor or knockdown of GSK-3beta resulted in enhanced TGF-beta1-mediated EMT, migration and collagen contraction in ARPE-19 cells, which were then abrogated by GSK-3beta overexpression and PI3K/AKT inhibitor. Importantly, GSK-3beta also mediated metabolic reprogramming in TGF-beta1-treated cells. Our results indicate that GSK-3beta plays a pivotal role in TGF-beta1-mediated EMT in ARPE-19 cells.CI - Copyright (c) 2017 Elsevier Inc. All rights reserved.

In this study, we investigated the underlying mechanism of the phosphoinositide 3-kinase/Akt- and Wnt/beta-catenin-mediated promotion of epithelial-to-mesenchymal transition by epigenetic regulation of histone acetylation in gastric cancer. First, we used immunohistochemistry to detect the expression of phosphorylated Akt, phosphorylated glycogen synthase kinase 3 beta, and beta-catenin in gastric cancer tissues and adjacent tissues. In addition, we confirmed that the phosphoinositide 3-kinase/Akt and Wnt/beta-catenin signaling pathways were correlated with tumorigenesis, progression, and maintenance of gastric cancer using the phosphoinositide 3-kinase inhibitor LY294002 and an inhibitor of the beta-catenin/TCF4 complex, FH535. epithelial-to-mesenchymal transition-related gene expression was measured by western blotting and quantitative real-time polymerase chain reaction assays. Furthermore, we detected the acetylation of histone H3 lysine 4 and lysine 27 using the FH535 and LY294002 inhibitors at different concentrations for 24 and 48 h. Finally, chromatin immunoprecipitation-quantitative polymerase chain reaction was performed to detect the specific binding of H3K27ac to the promoter of the epithelial-to-mesenchymal transition-related factor, Twist. Taken together, abnormal activation of the phosphoinositide 3-kinase/Akt and Wnt/beta-catenin signaling pathway was correlated with the gastric cancer progression and contributed to epithelial-to-mesenchymal transition regulation by controlling histone acetylation.

BACKGROUND: This study was aimed to investigate the epithelial differentiation of human adipose-derived mesenchymal stem cells (ADSCs) by inhibiting glycogen synthase kinase-3 (GSK3) and transforming growth factor beta (TGFbeta) signaling. METHODS AND RESULTS: STEMPRO human ADSCs at passage 2 were treated with CHIR99021 (GSK3 inhibitor), E-616452 (TGFbeta1 receptor kinase inhibitor), A-83-01 (TGFbeta type 1 receptor inhibitor), valproic acid (histone deacetylase inhibitor), tranylcypromine (monoamine oxidase inhibitor) and all-trans retinoic acid for 72 h. The mesenchymal-epithelial transition was shown by down-regulation of mesenchymal genes (Slug, Zinc Finger E-box Binding Homeobox 1 ZEB1, integrin alpha5 ITGA5 and vimentin VIM) and up-regulation of epithelial genes (E-cadherin, epithelial Cell Adhesion Molecule EpCAM, Zonula Occludens-1 ZO-1, occludin, deltaN p63 deltaNp63, Transcription Factor 4 TCF4 and Twist Family bHLH Transcription Factor TWIST), compared to untreated ADSCs. Cell morphology and stress fiber pattern were examined and the treated cells became less migratory in scratch wound closure assay. The formation of cell junction complexes was observed under transmission electron microscopy. Global gene expression using GeneChip((R)) Human Genome U133 Array (Affymetrix) showed that the treatment up-regulated 540 genes (containing genes for cell cycle, cytoskeleton reorganization, chemotaxis, epithelium development and regulation of cell migration) and down-regulated 483 genes. CONCLUSION: Human ADSCs were transited to epithelial lineage by inhibiting GSK3 and TGFbeta signaling. It can be an adult stem cell source for epithelial cell-based therapy.CI - Copyright (c) 2017 Elsevier Inc. All rights reserved.

epithelial-mesenchymal transition (EMT) plays a pivotal role in the invasion and metastasis of breast cancer. Livin is a recently identified member of the inhibitors of the apoptosis protein family, which has been revealed to facilitate the progression of several types of cancer. However, the role of Livin in EMT and metastasis of breast cancer and its underlying mechanisms are not fully elucidated. In the present study, the levels of Livin mRNA and protein expression were found to be elevated in breast cancer tissues and cell lines. In addition, Livin expression was positively correlated with TNM stage and lymph node metastasis in total and triple-negative breast cancer (TNBC) cases. Livin overexpression enhanced the migratory and invasive abilities of the MCF-7 cells, accompanied by increases in vimentin, N-cadherin, Snail, MMP-2 and MMP-7 and a decrease in E-cadherin. Conversely, the downregulation of Livin had the opposite effect in MDA-MB-231 cells. Furthermore, the upregulation of Livin expression markedly stimulated the activation of the p38/GSK3beta pathway, while the downregulation of Livin expression clearly suppressed the activation of the p38/GSK3beta pathway. In conclusion, our results revealed that Livin induced EMT through the activation of the p38/GSK3beta pathway, which in turn promoted the progression and metastasis of breast cancer, especially for TNBC.

This study investigated the effects of microRNA-135a (miR-135a) targeting of glycogen synthase kinase 3beta (GSK3beta) on the epithelial-mesenchymal transition (EMT), migration and invasion of bladder cancer (BC) cells by mediating the Wnt/beta-catenin signaling pathway. BC and adjacent normal tissues were collected from 165 BC patients. Western blotting and quantitative real-time PCR were used to detect the expression of GSK3beta, beta-catenin, cyclinD1, E-cadherin, vimentin and miR-135a in BC tissues and cells. Cells were assigned to blank, negative control (NC), miR-135a mimics, miR-135a inhibitors, small interfering RNA (siRNA)-GSK3beta or miR-135a inhibitors+siRNA-GSK3beta groups. miR-135a, beta-catenin, cyclinD1 and vimentin expression increased, while GSK3beta and E-cadherin expression decreased in BC tissues compared with adjacent normal tissues. Compared with the blank and NC groups, the expression of miR-135a, beta-catenin, cyclinD1 and vimentin was higher, and cell proliferation, migration, invasion and tumor growth were increased in the miR-135a mimics and siRNA-GSK3beta groups. These groups showed an opposite trend in GSK3beta and E-cadherin expression and cell apoptosis. The miR-135a inhibitors group was inversely correlated with the blank and NC groups. It was concluded that miR-135a accelerates the EMT, invasion and migration of BC cells by activating the Wnt/beta-catenin signaling pathway through the downregulation of GSK3beta expression.

Despite the availability of a number of treatment options, certain cases of primary prostate cancer (PCa) will develop into metastatic PCa, in which epithelialmesenchymal transition (EMT) serves an important role. Recently, a natural flavonoid known as 2'hydroxyflavanone (2HF) exerts remarkable anticancer activity on various types of cancer. Our previous study demonstrated that 2HF could promote apoptosis and inhibit the proliferation of PCa cells, but whether 2HF is involved in the regulation of EMT, and cell migration and invasion in metastatic PCa remains unknown. The present study used two different metastatic PCa cell lines (PC3 and DU145) to investigate the effects of 2HF on EMT, and cell migration and invasion. The results demonstrated that 2HF could inhibit EMT, and cell migration and invasion through the Wnt/betacatenin signaling pathway by suppressing GSK3beta phosphorylation, betacatenin expression and transactivation. In conclusion, the present study revealed a novel function of 2HF, which may be used to prevent or treat PCa metastasis.

epithelial-mesenchymal transition (EMT) is important for diabetic nephropathy (DN). Podocytes are specialized epithelial cells, which form a major component of the glomerular filtration barrier. Podocyte damage has been suggested to be the primary mechanism behind the albuminuria associated with DN. The present study aimed to determine the function of glycogen synthase kinase (GSK)3beta in EMT and barrier dysfunction of mouse podocytes exposed to high glucose (HG) conditions. Matured and differentiated podocytes were treated with normal glucose (NG), HG or NG + mannitol. Podocytes were also transfected with a small interfering RNA (siRNA) against GSK3beta or a scrambled siRNA, or were treated with lithium chloride (LiCl), a GSK3beta inhibitor, under NG or HG conditions. The expression levels of the epithelial cell markers, nephrin and podocin, and the myofibroblast cell markers, alphasmooth muscle actin (SMA) and fibronectin, in podocytes by western blot analysis and immunofluorescence staining, respectively. The monolayer barrier function was assessed by albumin inflow. The phosphorylation and activity levels of GSK3beta were also quantified. It was observed that HG promotes EMT in podocytes, due to the increased levels of podocin and nephrin expression and the reduced alphaSMA and fibronectin expression levels. HG also induced barrier dysfunction and increased the expression level of total GSK3beta, Try216phosphorylatedGSK3beta and the GSK3beta activity in podocytes. Transfection of GSK3beta siRNA or treatment with LiCl reversed the HGinduced EMT and barrier dysfunction in podocytes. In conclusion, the present study determined that GSK3beta is required for EMT and barrier dysfunction in podocytes under HG conditions; therefore, GSK3beta may be a novel target for the treatment of DN.