title: microRNA-20a enhances the epithelial-to-mesenchymal transition of colorectal cancer cells by modulating matrix metalloproteinases.
abstract: The mortality rates associated with colorectal cancer (CRC) are high due to metastasis. Epithelial-to-mesenchymal transition (EMT) is a key step in tumor metastasis. The aim of the present study was to investigate the function of microRNA-20a (miR-20a) in EMT. The expression of miR-20a was analyzed in CRC tissues and cell lines using the reverse transcription-quantitative polymerase chain reaction. Plasmids containing miR-20a short hairpin RNA and miR-20a mimics were transfected into SW620 and LS174T cell lines, respectively. Cell counting kit-8, Transwell® and wound healing assays were performed to assess the effects of miR-20a on cell proliferation, invasion and migration. EMT markers and matrix metalloproteinases (MMPs) were identified using western blotting. The results showed that increased expression of miR-20a in CRC tissues was associated with tumor invasion and lymph node metastasis (P<0.05). Further experiments indicated that miR-20a-knockdown inhibited the proliferation, invasion and migration of CRC cells, upregulated the expression of vimentin and tissue inhibitor of metalloproteinases-2 (TIMP-2) and downregulated the expression of E-cadherin, MMP-2 and MMP-9. The opposite effects were observed in CRC cell lines overexpressing miR-20a. In conclusion, these results have shown that the upregulation of miR-20a suppresses TIMP-2 expression, which subsequently increases the expression of MMP-2 and MMP-9, thereby promoting the EMT of CRC cells. These findings suggest that miR-20a represents a potential therapeutic target for patients with CRC.
authors.affiliation: Department of Gastrointestinal Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China.
authors.forename: Tao
authors.initials: T
authors.lastname: Xu
authors.affiliation: Department of Gastrointestinal Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China.
authors.forename: Changqing
authors.initials: C
authors.lastname: Jing
authors.affiliation: Department of Gastrointestinal Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China.
authors.forename: Yulong
authors.initials: Y
authors.lastname: Shi
authors.affiliation: Department of Gastrointestinal Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China.
authors.forename: Ruizheng
authors.initials: R
authors.lastname: Miao
authors.affiliation: Department of Gastrointestinal Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China.
authors.forename: Lipan
authors.initials: L
authors.lastname: Peng
authors.affiliation: Department of Gastrointestinal Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China.
authors.forename: Shuai
authors.initials: S
authors.lastname: Kong
authors.affiliation: Department of Gastrointestinal Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Department of Gastrointestinal Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong 250021, P.R. China.
authors.forename: Leping
authors.initials: L
authors.lastname: Li
keywords: colorectal cancer; epithelial-to-mesenchymal transition; microRNA-20a