Aims
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.
Conclusion
Our study indicates that miR-183 down-regulates MTA1 to inhibit the proliferation, EMT, migration and invasion of human NSCLC cells.
Methods
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.
Results
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.