A tumor suppressive role of lncRNA GAS5 in human colorectal cancer

AbstractObjectiveIt is already known that long non-coding RNA growth arrest-specific 5 (GAS5) is downregulated in human colorectal cancer (CRC) cells inhibiting cell proliferation. We further analyzed its involvement in cell cycle distribution and apoptosis induction.MethodsWe measured the expression level of GAS5 in CRC tissues and cell lines with the corresponding non-tumoral cells. We also analyzed the roles of GAS5 in modulation of cell growth, cell cycle distribution and apoptosis by the CCK-8 method and flow cytometry. Western blots were performed to evaluate the protein level of cyclin D1 and p21 after overexpression of GAS5ResultsGAS5 expression was significantly reduced in CRC samples and cell lines. Overexpression of GAS5 induced cell growth arrest and induced cell apoptosis in vitro. Meanwhile, we found that the growth suppressive role of GAS5 might be attributed to the inhibition of G1-S phase transition, reflected by the downregulation of cyclin D1 and upregulation of p21.ConclusionOur results demonstrate that GAS5 is a crucial tumor suppressor in human CRC cells.