MT2-MMP induces proteolysis and leads to EMT in carcinomas

// Yusi Liu 1, * , Xiaojiao Sun 2, * , Jinfa Feng 3, * , Li-Li Deng 4 , Yihao Liu 1 , Bokang Li 1 , Mingyue Zhu 1 , Changlian Lu 1 , Lingyun Zhou 5 1 Department of Biopharmaceutical Sciences, College of Pharmacy, Harbin Medical University, Harbin, China 2 Department of Pathophysiology, Harbin Medical University, Harbin, China 3 Department of General Surgery, Heilongjiang Province Hospital, Harbin, China 4 Department of Oncology, The Second Affiliated Hospital of Harbin Medical University, Harbin, China 5 Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, China * These authors have contributed equally to this work Correspondence to: Changlian Lu, email: lclian@aliyun.com Lingyun Zhou, email: zhoulingyun27@sina.com Keywords: MT2-MMP, cancer, epithelial-mesenchymal transition (EMT), E-cadherin, zonula occludens-1 (ZO-1) Received: January 20, 2016     Accepted: June 09, 2016     Published: June 21, 2016 ABSTRACT Epithelial-mesenchymal transition (EMT) is critical for carcinoma invasiveness and metastasis. To investigate the role of membrane-type-2 matrix metalloproteinase (MT2-MMP) in EMT, we generated lentiviral constructs of wild-type (WT) and an inactive Glu260Ala (E260A) mutant MT2-MMP and derived stably transfected HCT116 and A549 cell lines. WT-transfected cells appeared mesenchymal-like, whereas cells transfected with the E260A mutant were epithelial-like, as were cells treated with an MMP inhibitor (GM6001). Expression of E-cadherin, β-catenin, and zonula occludens-1 was lower in cells transfected with WT MT2-MMP compared to vector controls, cells treated with GM6001, or cells transfected with the E260A mutant. An 80-kD N-terminal fragment of E-cadherin was immunoprecipitated in conditioned medium from WT MT2-MMP cells, but not in the medium from vector controls, cells treated with GM6001, or E260A mutant cells. When endogenous expression of MT2-MMP in A2780 human ovarian cancer cells was inhibited using GM6001 or MT2-MMP-specific siRNA, levels of the 80-kD E-cadherin fragment in conditioned medium were decreased. Chick embryo chorioallantoic membrane invasion assays demonstrated that cells transfected with WT MT2-MMP were more invasive than cells transfected with control vector, treated with GM6001, or transfected with the E260A mutant. These results suggest that MT2-MMP degrades adherens and tight junction proteins and results in EMT, making it a potential mediator of EMT in carcinomas.