ISL treatment inhibits the activation of the PI3K/AKT signaling pathway in A549 cells. (A) Effects of ISL on protein expression of AKT, mTOR, p-AKT, p-mTOR, P70 and Cyclin D1 in A549 cells, determined using western blot analysis. β-tubulin was used as the loading control. (B) Quantitative results of protein expression. The data was calculated using mean ± standard deviation of three repeats. *P<0.05 compared with NC. NC, negative control; ISL, Isoliquiritigenin; PI3K, phosphatidylinositol 3-kinase; AKT, AKT serine/threonine kinase; mTOR, mammalian target of rapamycin; p, phosphorylated.