CASP3 and cancer: In the most studies, cell cycle arrest induced by RES in drug-resistant cancer cells was observed along with the activation of apoptosis, which is proved by an increase in apoptotic signal molecules, including PTEN, p53, and active caspases-3, -7, -8, and -9, and a decrease in anti-apoptotic regulators, such as p-AKT and EGFR [16,37,44,46,47].