Oxyresveratrol inhibits the growth of human lung squamous cell carcinoma cells by triggering S-phase arrest and apoptosis
Oxyresveratrol is found in mulberry (Morus alba L.) and possesses antioxidant, anti-inflammatory, and antitumor activities. However, to the best of our knowledge, relevant studies on the effects of oxyresveratrol on human lung squamous cell carcinoma cells are lacking. The aim of this study was to evaluate the antitumor activity of oxyresveratrol in human NCI-H520 lung squamous cell carcinoma cells using in vitro and in vivo approaches. Oxyresveratrol induced NCI-H520 cell apoptosis in an intrinsic signaling pathway. Therefore, oxyresveratrol resulted in enhanced cell numbers at the sub-G1 phase, increased caspase-3 and -9 activities, caused the MMP (mitochondrial membrane potential) to collapse, and decreased Bcl-2 and cyclin D protein expressions. In addition, oxyresveratrol induced arrest at the S-phase cell cycle in NCI-H520 cells through downregulating the cell-cycle-related protein expressions of cyclin A, cyclin B, and cdk2. These results indicated that oxyresveratrol inhibited the proliferation and induced apoptosis by activating an intrinsic pathway in NCI-H520 non-small cell lung cancer cells. Our results suggest that oxyresveratrol can be used as an alternative remedy for human non-small-cell lung cancer.