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FZD7

Frizzled-7 (FZD7) has been demonstrated as a critical receptor of the Wnt signaling and involves in tumorigenesis and metastasis in many cancer types. However, limited information was found in cervical cancer. The aim of this study was to investigate the functional role of FZD7 in migration, invasion, and epithelial-mesenchymal transition (EMT) of cervical cancer cells. HeLa and SiHa cervical carcinoma cell lines with FZD7 expression were chosen in this study. A short hairpin RNA (shRNA) construct targeting FZD7 mRNA was transfected into HeLa and SiHa cells, and the stably transfected cell lines were obtained through G418 screening. Functional experiments were further performed to assess whether FZD7 down-regulation affects the migration, invasion, and EMT of HeLa and SiHa cells. Our results revealed that down-regulation of FZD7 expression significantly inhibited cell invasion and migration, as well as decreased the expression and activities of MMP2 and MMP9 in both cell types. Additionally, FZD7 silencing resulted in down-regulation of mesenchymal markers including Vimentin and Snail while increased the levels of epithelial marker E-cadherin. We further found that decreased FZD7 expression inhibited the phosphorylation levels of JNK and c-jun in both HeLa and SiHa cells, as determined by Western blot analysis and immunofluorescence. Overall, our results indicate that shRNA-mediated knockdown of FZD7 inhibits invasion, metastasis, and EMT of cervical cancer cells. FZD7 may provide a promising therapeutic target in cervical cancer.

BACKGROUND: Metastasis underlies most colorectal cancer mortality. cancer cells spread through the body as single cells or small clusters of cells that have an invasive, mesenchymal, nonproliferative phenotype. At the secondary site, they revert to a proliferative "tumor constructing" epithelial phenotype to rebuild a tumor. We previously developed a unique in vitro three-dimensional model, called LIM1863-Mph, which faithfully recapitulates these reversible transitions that underpin colorectal cancer metastasis. Wnt signaling plays a key role in these transitions and is initiated by the coupling of extracellular Wnt to Frizzled (FZD). Using the LIM1863-Mph model system we demonstrated that the Wnt receptor FZD7 is necessary for mesenchymal to epithelial transition (MET). Here we investigate the role of Wnt in MET. RESULTS: Wnt secretion is dependent on palmitoylation by Porcupine (PORC). A PORC inhibitor (IWP2) that prevents Wnt secretion, blocked the epithelial transition of mesenchymal LIM1863-Mph cells. Wnt gene array analysis identified several Wnts that are upregulated in epithelial compared with mesenchymal LIM1863-Mph cells, suggesting these ligands in MET. Wnt2B was the most abundant differentially expressed Wnt gene. Indeed, recombinant Wnt2B could overcome the IWP2-mediated block in epithelial transition of mesenchymal LIM1863-Mph cells. CONCLUSIONS: Wnt2B co-operates with Frizzled7 to mediate MET in colorectal cancer. developmental Dynamics 247:521-530, 2018. (c) 2017 Wiley Periodicals, Inc.CI - (c) 2017 Wiley Periodicals, Inc.

A sub-population of chemoresistant cells exhibits biological properties similar to cancer stem cells (CSCs), and these cells are believed to be a main cause for tumor relapse and metastasis. In our study, we explored the role of SOX8 and its molecular mechanism in the regulation of the stemness properties and the epithelial mesenchymal transition (EMT) of cisplatin-resistant tongue squamous cell carcinoma (TSCC) cells. We found that SOX8 was upregulated in cisplatin-resistant TSCC cells, which displayed CSC-like properties and exhibited EMT. SOX8 was also overexpressed in chemoresistant patients with TSCC and was associated with higher lymph node metastasis, advanced tumor stage and shorter overall survival. Stable knockdown of SOX8 in cisplatin-resistant TSCC cells inhibited chemoresistance, tumorsphere formation, and EMT. The Wnt/beta-catenin pathway mediated the cancer stem-like properties in cisplatin-resistant TSCC cells. Further studies showed that the transfection of active beta-catenin in SOX8 stable-knockdown cells partly rescued the SOX8 silencing-induced repression of stem-like features and chemoresistance. Through chromatin immunoprecipitation and luciferase assays, we observed that SOX8 bound to the promoter region of Frizzled-7 (FZD7) and induced the FZD7-mediated activation of the Wnt/beta-catenin pathway. In summary, SOX8 confers chemoresistance and stemness properties and mediates EMT processes in chemoresistant TSCC via the FZD7-mediated Wnt/beta-catenin pathway.CI - (c) 2017 UICC.