PTEN and neoplasm: The effect of WM622 on tumor growth was stronger than that of 5-Fu;Western experiments showed that expression levels of p-PI3K (Tyr458), p-AKT(Thr308), p-EGFR(Tyr1068) and p-GSK3β(Ser9) were down-regulated and the level of PTEN was up-regulated dose dependently