MicroRNA 145 may play an important role in uveal melanoma cell growth by potentially targeting insulin receptor substrate-1.

Abstract:

BACKGROUND:MicroRNAs (miRNAs) contribute to tumorigenesis by acting as either oncogenes or tumor suppressor genes. In this study, we investigated the role of miR-145 in the pathogenesis of uveal melanoma. METHODS:Expression profiles of miRNAs in uveal melanoma were performed using Agilent miRNA array. Quantitative real-time polymerase chain reaction was used to screen the expression levels of miR-145 in normal uveal tissue, uveal melanoma tissue, and uveal melanoma cell lines. Lenti-virus expression system was used to construct MUM-2B and OCM-1 cell lines with stable overexpression of miR-145. Cell proliferation, cell cycle, and cell apoptosis of these miR-145 overexpression cell lines were examined by MTT assay and flow cytometry respectively. The target genes of miR-145 were predicted by bioinformatics and confirmed using a luciferase reporter assay. The expression of insulin-like growth factor-1 receptor (IGF-1R), insulin receptor substrate-1 (IRS-1) proteins was determined by Western blotting analysis. IRS-1 was knocked down in OCM-1 cells. TUNEL, BrdU, and flow cytometry assay were performed in IRS-1 knocked down OCM-1 cell lines to analyze its function. RESULTS:Forty-seven miRNAs were up regulated in uveal melanoma and 61 were down regulated. miR-145 expression was significantly lower in uveal melanoma sample and the cell lines were compared with normal uveal sample. Overexpression of miR-145 suppressed cell proliferation by blocking the G1 phase entering S phase in uveal melanoma cells, and promoted uveal melanoma cell apoptosis. IRS-1 was identified as a potential target of miR-145 by dual luciferase reporter assay. Knocking down of IRS-1 had similar effect as overexpression of miR-145. CONCLUSION:miR-145 might act as a tumor suppressor in uveal melanoma, and downregulation of the target IRS-1 might be a potential mechanism.

journal_name

Chin Med J (Engl)

journal_title

Chinese medical journal

authors

Li Y,Huang Q,Shi X,Jin X,Shen L,Xu X,Wei W

subject

Has Abstract

pub_date

2014-01-01 00:00:00

pages

1410-6

issue

8

eissn

0366-6999

issn

2542-5641

journal_volume

127

pub_type

杂志文章