[Influence of phosphatidylinositol-3-kinases P85α silence by RNA interference on cell cycle and apoptosis of colorectal cancer cells in vitro].

OBJECTIVE: To investigate the effect of phosphatidylinositol- 3-kinases(PI3K) P85α silence on cell cycle and apoptosis of colorectal cancer cells. METHODS: Four shRNA vectors(shRNA/89, 324, 1073 and 1123) and one negative control vector were designed and stably transfected into SW480 cells. Western blotting was used to determine the expression level of P85α. Flow cytometry was used to determine the PI-labeled cycle after stable transfection. Annexin V-FITC kit was used to determine the apoptosis. RESULTS: Western blotting analysis showed that the expression level of PI3K P85α protein was significantly decreased in cells transfected with shRNA/324 vector. The inhibition rate was 90%. The group was selected for the following experiments. G1 phase cells in the interference group and the control group were (62.4±2.7)% and (51.2±3.5)%, respectively. S phase cells in the interference group and the control group were (23.9±1.7)% and (34.1±3.4)%, respectively. Apoptosis cells induced by 5-FU of interference group and control group were(11.1±3.7)% and (1.4±0.6)%, respectively. The differences were all significant (P<0.05). CONCLUSIONS: Depletion of PI3K P85α can significantly induce SW480 cell cycle arrest and sensitize SW480 cells to 5-FU induced apoptosis. PI3K P85α may be a new therapeutic target for colorectal cancer cells.