MicroRNA-183 Acts as a Tumor Suppressor in Human Non-Small Cell Lung Cancer by Down-Regulating MTA1.

MicroRNAs (miRs) often contribute to the progression of non-small cell lung cancer (NSCLC) via regulation of mRNAs that are involved in lung homeostasis. We conducted a study aimed at exploring the roles of miR-183 in the proliferation, epithelial-mesenchymal transition (EMT), invasion and migration of human NSCLC cells via targeting MTA1. NSCLC and adjacent normal tissues were collected from 194 patients with NSCLC. Positive expression of MTA1 protein was detected by immunohistochemistry. The highest levels of expression of miR-183 were detected using RT-qPCR in SPC-A-1 cells, which were selected and assigned to the following groups: blank, negative control (NC), miR-183 mimic, miR-183 inhibitor, siRNA-MTA1, and miR-183 inhibitor + siRNA-MTA1. The expression of miR-183 and the mRNA and protein expression of MTA1, E-cadherin, Vimentin, Snail, PCNA, Bax and Bcl-2 in tissues and transfected cells were measured using RT-qPCR and western blot analysis. Cell proliferation, apoptosis, migration and invasion were evaluated by CCK-8, flow cytometry, scratch tests and Transwell assays. Tumor xenografts were conducted in nude mice to determine tumor growth. SPC-A-1 cells with the highest levels of miR-183 expression were selected. Compared with adjacent normal tissues, the expression of miR-183 and the mRNA and protein expression of E-cadherin and Bax were decreased in NSCLC tissues, while mRNA and protein expression of MTA1, Vimentin, snail, PCNA and Bcl-2 were increased. MiR-183 was over-expressed in the miR-183 mimic group and under-expressed in the miR-183 inhibitor and miR-183 inhibitor + siRNA-MTA1 groups. In the miR-183 mimic and siRNA-MTA1 groups, the mRNA and protein expression of E-cadherin and Bax, as well as cell apoptosis, were enhanced, while the expression levels of MTA1, Vimentin, snail, PCNA and Bcl-2 mRNA and protein, cell proliferation, migration, invasion and tumor growth were reduced relative to the blank and NC groups. The miR-183 inhibitor group exhibited an opposite trend. Our study indicates that miR-183 down-regulates MTA1 to inhibit the proliferation, EMT, migration and invasion of human NSCLC cells.

Yang CL ，Zheng XL ，Ye K ，Ge H ，Sun YN ，Lu YF ，Fan QX ... -  《-》

Effects of microRNA-183 on epithelial-mesenchymal transition, proliferation, migration, invasion and apoptosis in human pancreatic cancer SW1900 cells by targeting MTA1.

This study aims to explore effects of miR-183 on epithelial-mesenchymal transition (EMT) and invasion by targeting MTA1 in human pancreatic cancer (PC) cells. Totally, 108 PC patients admitted in Wenzhou Central Hospital and Wenzhou People's Hospital, The Dingli Clinical Institute of Wenzhou Medical University from March 2010 to March 2014 were enrolled. qRT-PCR and immunohistochemistry were applied to examine expression of MTA1 mRNA and protein. Samples were divided into 6 groups: blank, NC, miR-183 mimics, miR-183 inhibitors, MTA1-siRNA and miR-183 inhibitors +MTA1-siRNA groups. CCK8 method was employed for determining cell proliferation rate, flow cytometry for cell apoptosis rate, scratch test for cell migration and Transwell assay for cell invasion. qRT-PCR and Western blotting were used to determine expression of MTA1, E-cadherin and Vimentin mRNA and protein. Positive expression rate of MTA1 was upregulated in PC tissues, and expression of miR-183 and MTA1 was associated with differentiation, migration, tumor size, TNM. The miR-183 mimics and MTA1-siRNA groups showed a decrease in proliferation, migration and invasion, whereas increased apoptosis, in comparison with blank and NC groups, as expression of MTA1 and Vimentin mRNA and protein were reduced, expression of E-cadherin mRNA and protein was elevated. Compared to blank and NC groups, the miR-183 inhibitors group exhibited enhanced proliferation, migration and invasion and inhibited apoptosis; increased expressions of MTA1 and Vimentin mRNA and protein and decreased expressions of E-cadherin mRNA and protein. Our study supported that miR-183 could repress EMT and invasion of human PC cells through inhibition of MTA1 expression.

Lin X ，Zheng L ，Song H ，Xiao J ，Pan B ，Chen H ，Jin X ，Yu H ... -  《-》

MTA1 promotes epithelial to mesenchymal transition and metastasis in non-small-cell lung cancer.

Ma K ，Fan Y ，Dong X ，Dong D ，Guo Y ，Wei X ，Ning J ，Geng Q ，Wang C ，Hu Y ，Li M ，Niu W ，Li E ，Wu Y ... -  《Oncotarget》

Downregulation of N-Acetylglucosaminyltransferase GCNT3 by miR-302b-3p Decreases Non-Small Cell Lung Cancer (NSCLC) Cell Proliferation, Migration and Invasion.

GCNT3 is a member of N-acetylglucosaminyltransferase family involved with mucin biosynthesis. GCNT3 aberrant expression is known to promote the progression of several human cancers. However, its role in tumorigenesis and the progression of non-small cell lung cancer (NSCLC) has not been well-characterized. Our study investigated the functional mechanisms of GCNT3 regulated by microRNAs (miRNAs) in NSCLC. The differential expression of mRNAs in NSCLC tissues and matched adjacent non-cancerous lung tissues from patients in Xuanwei, Yunnan province, China, was screened via mRNA microarray. The expression of GCNT3 and its correlation with NSCLC progression was measured in 92 paired tumor tissues and adjacent normal tissues. The functions of GCNT3 in NSCLC cells and its underlying mechanisms were measured using siRNA and GCNT3-expression vectors. The miRNA immunoprecipitation (miRIP) method was used to identify the miRNAs targeting GCNT3. The protein were measured using western blot assay, and the mRNAs were measured by quantitative real-time PCR (qRT-PCR) assay. Cell proliferation was measured using Cell Counting Kit-8 (CCK-8) and a colony forming assays; cell migration and invasion assays were performed using 24-well Transwell chambers with 8-μm pores filter, and analyses of the cell cycle and apoptosis were performed via flow cytometric analysis. The dual luciferase reporter assay was performed to confirm whether GCNT3 gene was a direct target of miR-302b-3p. GCNT3 was found to be highly expressed in both NSCLC tissues and cell lines, and higher expression correlated significantly with advanced tumor-node-metastasis (TNM) stage, positive lymph node metastasis, and poor overall survival. Knockdown of GCNT3 inhibited the proliferation, migration and invasion ability of NSCLC cells, while overexpression facilitated these activities. Further mechanistic experiments using miRIP and dual luciferase reporter assays revealed that GCNT3 was a direct target of miR-302b-3p. Low expression of miR-302b-3p was found in NSCLC cells and negatively correlated with GCNT3 levels, while miR-302b-3p overexpression inhibited the proliferation, migration and invasion of NSCLC cells. Co-transfection with miR-302b-3p and the expression vector of GCNT3 abrogated the effects of mir-302b-3p, confirming that miR-302b-3p inhibited NSCLC progression by targeting GCNT3. Western blotting revealed that E-cadherin, N-cadherin, vimentin, p-Erk and cyclin D1 were downstream molecules of miR-302b-3p/GCNT3 pathway. miR-302b-3p/GCNT3 axis regulated cell proliferation, migration, and invasion by activating the Erk signaling pathway and epithelial-mesenchymal transition (EMT), which was identified as a potential therapeutic target for NSCLC.

Li Q ，Ran P ，Zhang X ，Guo X ，Yuan Y ，Dong T ，Zhu B ，Zheng S ，Xiao C ... -  《-》

Effect of microRNA-135a on Cell Proliferation, Migration, Invasion, Apoptosis and Tumor Angiogenesis Through the IGF-1/PI3K/Akt Signaling Pathway in Non-Small Cell Lung Cancer.

This study explored the ability of microRNA-135a (miR-135a) to influence cell proliferation, migration, invasion, apoptosis and tumor angiogenesis through the IGF-1/PI3K/Akt signaling pathway in non-small cell lung cancer (NSCLC). NSCLC tissues and adjacent normal tissues were collected from 138 NSCLC patients. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression levels of miR-135a and IGF-1, PI3K, Akt, VEGF, bFGF and IL-8 mRNA; western blotting was used to determine the expression levels of IGF-1, PI3K and Akt protein; and enzyme-linked immunosorbent assay (ELISA) was used to analyze the expression levels of VEGF, bFGF and IL-8 protein. Human NSCLC cell lines (A549, H460, and H1299) and the human bronchial epithelial cell line (HBE) were selected. A549 cells were assigned to blank, negative control (NC), miR-135a mimics, miR-135a inhibitors, IGF-1 siRNA and miR-135a inhibitors + IGF-1 siRNA groups. The following were performed: an MTT assay to assess cell proliferation, a scratch test to detect cell migration, a Transwell assay to measure cell invasion, and a flow cytometry to analyze cell apoptosis. The expression level of miR-135a was lower while those of IGF-1, PI3K and Akt mRNA were higher in NSCLC tissues than in the adjacent normal tissues. Dual-luciferase reporter assay indicated IGF-1 as a target of miR-135a. The in vitro results showed that compared with the blank group, cell proliferation, migration and invasion were suppressed, mRNA and protein levels of IGF-1, PI3K, Akt, VEGF, bFGF and IL-8 were reduced, and cell apoptosis was enhanced in the miR-135a mimics and IGF-1 siRNA groups. Compared with the IGF-1 siRNA group, cells in the miR-135a inhibitors + IGF-1 siRNA group demonstrated increased cell proliferation, migration and invasion, elevated mRNA and protein levels of IGF-1, PI3K, Akt, VEGF, bFGF and IL-8 and reduced cell apoptosis. These findings indicated that miR-135a promotes cell apoptosis and inhibits cell proliferation, migration, invasion and tumor angiogenesis by targeting IGF-1 gene through the IGF-1/PI3K/Akt signaling pathway in NSCLC.

Zhou Y ，Li S ，Li J ，Wang D ，Li Q ... -  《-》