N-cadherin functions as a growth suppressor in a model of K-ras-induced PanIN
ONCOGENE
Authors: Su, Y.; Li, J.; Shi, C.; Hruban, R. H.; Radice, G. L.
Abstract
Cadherin subtype switching from E-cadherin to N-cadherin is associated with the epithelial-to-mesenchymal transition (EMT), a process required for invasion and dissemination of carcinoma cells. We found that N-cadherin is expressed in human and mouse pancreatic intraepithelial neoplasia (PanIN), suggesting that N-cadherin may also have a role in early-stage pancreatic cancer. To investigate the role of N-cadherin in mouse PanIN (mPanIN), we simultaneously activated oncogenic K-ras(G12D) and deleted the N-cadherin (Cdh2) gene in the murine pancreas. Genetic ablation of N-cadherin (N-cad KO) caused hyperproliferation, accelerated mPanIN progression, and early tumor development in K-ras(G12D) mice. Decreased E-cadherin and redistribution of beta-catenin accompanied the loss of N-cadherin in pancreatic ductal epithelial cells (PDEC). Nuclear accumulation of beta-catenin and its transcription co-activator Tcf4 led to activation of Wnt/beta-catenin target genes. Unexpectedly, loss of N-cadherin in the K-rasG12D model resulted in increased mPanIN progression and tumor incidence. These in vivo results demonstrate for the first time that N-cadherin functions as a growth suppressor in the context of oncogenic K-ras.
MicroRNA-124 Functions as a Tumor Suppressor by Regulating CDH2 and Epithelial-Mesenchymal Transition in Non-Small Cell Lung Cancer
CELLULAR PHYSIOLOGY AND BIOCHEMISTRY
Authors: Ma, Teng; Zhao, Ye; Wei, Ke; Yao, Guoliang; Pan, Chunfeng; Liu, Bin; Xia, Yang; He, Zhicheng; Qi, Xiaotong; Li, Zhi; Wang, Jun; Shao, Yongfeng
Abstract
Background/Aims: Abnormal expression of microRNA-124 (miR-124) was found in non-small cell lung cancer (NSCLC). However, the association between miR-124 and CDH2 has not been reported yet. This study aims to reveal the inhibiting effects of miR-124 on the expression of CDH2 in NSCLC. Methods: Quantitative real-time polymerase chain reaction was used to evaluate the expression of miR-124 and CDH2 in NSCLC tissues. Cell viability, apoptosis and invasion assays were carried out in NSCLC cell lines after transfection. The regulation mechanism was confirmed by luciferase report assay and western blot (WB). Results: Significantly decreased expression of miR-124 was found in NSCLC specimens and cell lines. Overexpression of miR-124 apparently suppressed the proliferation and invasion of NSCLC cell lines in vitro. Luciferase report assay and WB revealed that CDH2 was a target gene of miR-124. Furthermore, results of WB showed that epithelial-mesenchymal transition (EMT) could be inhibited by up-regulation of miR-124. Conclusions: Taken together, our findings present the first evidence that miR-124 could suppress the expression of CDH2 and regulate EMT, which might lead to a potential therapeutic strategy focusing on miR-124 and CDH2 for human lung cancer. (C) 2016 The Author(s) Published by S. Karger AG, Basel