The effect of microRNA-29a on the proliferation and migration of breast cancer cell via phosphatase and tensin homologue deleted on chromosome ten/phosphatidylinositol 3 kinase/protein kinase B signal pathway

Abstract

Objective To explore microRNA (miRNA, miR)-29a on the proliferation and migration of breast cancer cell MCF-7 via phosphatase and tensin homologue deleted on chromosome ten/phosphatidylinositol 3 kinase/protein kinase B (PTEN/PI3K/Akt) signal pathway. Methods miR-29a inhibitor and miR-29a NC were transfected into MCF-7 cell by liposome Lipofectamine™3000. The expression of miR-29a was detected by real-time quantitative polymerase chain reaction (Real-time PCR). Cell viability was detected by cell counting kit-8 (CCK-8) assay. Cell apoptotic rate and cell cycle was detected by flow cytometry. Cell migration ability was detected by Transwell method. The expression of B cell lymphoma/leukemia-2 (bcl-2), Cyclin D1, matrix metalloproteinase (MMP)-2, MMP-9, PTEN, PI3K and phosphorylated Akt (p-Akt) was detected by Western blotting. Results The expression of miR-29a in miR-29a inhibitor group (0.53±0.05) was lower than that in miR-29a NC (2.74±0.27) (P<0.05). Cell viability in miR-29a inhibitor group (0.35±0.02) was lower than that in miR-29a NC group (0.58±0.05) (P<0.05). The early apoptosis rate (15.38±1.54)%, late apoptosis rate (23.69±2.37)% in miR-29a inhibitor group were higher than that in miR-29a NC group [ (2.53±0.23)%, (3.17±0.31)%] (P<0.05). The cell cycle G1 phase in miR-29a inhibitor group was longer than that of miR-29a NC group (P<0.05). Cell migration number in miR-29a inhibitor group (42.87±4.88) was lower than that in miR-29a NC group (136.49±10.37) (P<0.05). The expression of bcl-2, Cyclin D1, MMP-2, MMP-9, PI3K and p-Akt in miR-29a inhibitor group was lower than that in miR-29a NC group (P<0.05). The expression of PTEN in miR-29a inhibitor group was higher than that in miR-29a NC group (P<0.05). Conclusion Down-regulation expression of miR-29a could suppress proliferation and migration in breast cancer MCF-7 cell via inhibition of PTEN/PI3K/Akt signal pathway. Key words: MicroRNA-29a; Breast cancer; Proliferation; Migration; Phosphatase and tensin homologue deleted on chromosome ten/phosphatidylinositol 3 kinase/protein kinase B signal pathway