PIK3CA and cervical cancer: To further determine the function of PI3K E542K and E545K in cervical cancer, we introduced PI3K E542K and E545K cDNA into SiHa and MS751 cells and established SiHa/PI3K E542K, SiHa/PI3K E545K, MS751/PI3K E542K, and MS751/PI3K E545K cells stably expressing PI3K E542K and E545K cDNA (Fig. 2a).