ZC3H13 is a canonical CCCH zinc finger protein, which harbors a somatic frame‐shift mutation in colorectal cancer (CRC). However, its expression and biological function were still uncertain. In the current study, we found that ZC3H13 was served as a tumor suppressor in CRC cells, which decreased the expression of Snail, Cyclin D1, and Cyclin E1, and increased the expression of Occludin and Zo‐1 through inactivating Ras–ERK signaling pathway. Furthermore, reduction of ZC3H13 associated with advanced TNM stage (p = 0.02), positive regional lymph node metastasis ( p = 0.01). Taken together, the current study indicated that ZC3H13 may be an upstream regulator of Ras–ERK signaling pathway and suppressed invasion and proliferation of CRC.

The scaffolding protein WWC (WW and C2-domain containing) family is known to regulate cell proliferation and organ size via the Hippo signalling pathway. However, the expression level of WWC3 in human tumours and the mechanisms underlying its role in cellular signal transduction have not yet been reported. Herein, we explored the potential roles of WWC3 in lung cancer cells and the corresponding molecular mechanisms. We found low WWC3 expression in both lung cancer cell lines and lung cancer specimens, which was associated with low differentiation, advanced pTNM stage, positive lymph node metastasis, and poor prognosis in patients with lung cancer. Moreover, the overexpression of WWC3 inhibited the proliferation and invasiveness of lung cancer cells. These effects were mediated by the inhibition and stimulation of the Wnt and Hippo pathways, respectively, in vitro and in vivo. Specifically, WWC3 interacts with Dishevelled (Dvl) proteins, prevents casein kinase 1 from phosphorylating Dvls, and inhibits -catenin nuclear translocation to inhibit the Wnt pathway. Deleting the WW and C-terminal PDZ-binding domains of WWC3 abrogated these effects. Moreover, the interaction of WWC3 with Dvls reduced the interaction between WWC3 and large tumour suppressor 1 (LATS1), as well as decreasing LATS1 phosphorylation to increase the nuclear importation of yes-associated protein (YAP) and attenuate the Hippo pathway. Deleting the WW domain of WWC3 abrogated this effect. These findings demonstrate the molecular interplay between WWC3, Dvls, and LATS1, and reveal a link between the Wnt and Hippo pathways, which provides a potential target for clinical intervention in lung cancer.

Transmembrane protein 88 (TMEM88) is a transmembrane protein that plays a crucial role in regulating human stem cell differentiation and embryonic development. However, its expression and clinicopathologic significance in human neoplasms is unclear. In this study, the expression and subcellular localizations of TMEM88 were assessed in 214 cases of non-small cell lung cancer (NSCLC). Notably, TMEM88 was highly expressed in the cytosol of $60% NSCLC specimens examined. Higher expression of cytosolic TMEM88 in NSCLC correlated significantly with poor differentiation, high TNM stage, lymph node metastasis, and inferior survival. In NSCLC cells displaying membrane-localized TMEM88, we observed an inhibition of canonical Wnt signaling due to interactions of TMEM88 with the Wnt pathway factor Dishevelled (DVLS). In contrast, NSCLC cells with cytosol-localized TMEM88 lacked effects on Wnt signaling. Cytosolic interactions of TMEM88 and DVLS increased the expression of phosphorylated, active forms of p38, GSK3b (Thr390), and Snail, thereby reducing the expression of the tight junction-associated proteins ZO-1 and occludin, effects associated with enhanced invasive and metastatic cell characters. Importantly, attenuating the expression of cytosolic TMEM88 reduced metastatic prowess in xenograft models. Overall, our findings show how mislocalization of TMEM88 to the cytosol in NSCLC cells ablates its Wnt pathway regulatory properties, thereby promoting invasion and metastasis by activating the p38-GSK3b-Snail signaling pathway. Cancer Res; 75(21); 4527-37. Ó2015 AACR.

BackgroundZinc-finger protein-326 (ZNF326) was initially found in the NIH3T3 cell line to regulate cell growth, however, the expression and underlying role of ZNF326 in human tumours, especially in glioma, is not fully understood.MethodsImmunohistochemistry was applied to detect the expression of ZNF326 in glioma tissues, and statistical analysis was used to analyse the relationship between ZNF326 expression and clinicopathological factors. The effect of ZNF326 on glioma cells proliferation and invasion was conducted by functional experiments both in vivo and in vitro. Chromatin immunoprecipitation and dual-luciferase assays were performed to demonstrate that histone deacetylase enzyme-7 (HDAC7) is the target gene of ZNF326. Immunoblotting, real-time PCR, GST-pulldown and co-immunoprecipitation assays were used to clarify the underlying role of ZNF326 on Wnt pathway activation.ResultsHigh nuclear expression of ZNF326 was observed in glioma cell lines and tissues, and closely related with advanced tumour grade in the patients. Moreover, ectopic ZNF326 expression promoted the proliferation and invasiveness of glioma cells. Mechanistically, ZNF326 could activate HDAC7 transcription by binding to a specific promoter region via its transcriptional activation domain and zinc-finger structures. The interaction of the up-regulated HDAC7 with β-catenin led to a decrease in β-catenin acetylation level at Lys-49, followed by a decrease in β-catenin phosphorylation level at Ser-45. These changes in β-catenin posttranscriptional modification levels promoted its redistribution and import into the nucleus. Additionally, ZNF326 directly associated with β-catenin in the nucleus, and enhanced the binding of β-catenin to TCF-4, serving as a co-activator in stimulating Wnt pathway.ConclusionsOur findings elucidated ZNF326 promotes the malignant phenotype of human glioma via ZNF326-HDAC7-β-catenin signalling. This study reveals the vital role and mechanism of ZNF326 in the malignant progression of glioma, and provides the reference for finding biomarkers and therapeutic targets for glioma.Electronic supplementary materialThe online version of this article (10.1186/s13046-019-1031-4) contains supplementary material, which is available to authorized users.

BackgroundDisorders of cell adhesion are critical steps in cancer progression in which varieties of markers including cadherins are involved in.Btbd7 was found to inhibit E-cadherin expression in MDCK cells and play important roles during branching morphogenesis of embryonic salivary glands and lungs. However its function in malignant tumors is largely unknown. The aim of this study is to investigate the clinicopathological significance and possible function of Btbd7 in non-small cell lung cancer.MethodsImmunohistochemistry and Western blotting were used to investigate Btbd7 expression in non-small cell lung cancer and lung tissues. The clinicopathological association and the overall survival was analyzed. In vitro experiments were performed using siRNA to investigate the function of Btbd7 in lung cancer cells.ResultsBtbd7 expression was elevated in non-small cell lung cancer tissues compared to normal lung tissues. Increased Btbd7 expression was significantly associated with lymph node metastasis, reduced E-cadherin expression and patients’ poor clinical outcome. Downregulation of Btbd7 expression in lung cancer cells by siRNA significantly inhibits cancer cell invasion and effectively restores E-cadherin expression in cancer cell membrane.ConclusionsBtbd7 contributes to reduced expression of E-cadherin and may be a promising cancer marker in non-small cell lung cancer.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2407-14-704) contains supplementary material, which is available to authorized users.