Diallyl disulfide induced cell cycle arrest in G₁ phase by downregulation of cyclin D1 and CDK4 in human nasopharyngeal carcinoma CNE2 cells

Aim: To investigate the effect of diallyl disulfide (DADS) on human nasopharyngeal carcinoma CNE2 cell line and its underlying molecular mechanism. Motheds: The antiproliferative effect of DADS in different concentrations on CNE2 cell line was measured by MTT assay. Cell cycle analysis was analyzed by flow cytometry. The expression levels of cyclin D1 and CDK4 were detected by RT-PCR and Western blot. Results: The MTT assay showed that DADS had potent antiproliferative effect on CNE2 in a dose-dependent manner. After 90,140,240 and 400 μmol·L^-1 DADS treatment for 48 hours, the viabilities of CNE2 cells were inhibited by 4.0%, 13.8%, 25.8% and 51.2%, respectively (P < 0.05). Flow cytometry analysis revealed that CNE2 cells of G₁ phase were arrested after exprosed to different concentrations of DADS. The expression levels of cyclin D1, CDK4 were decreased significantly after treated with DADS in a dose-dependent manner using RT-PCR and Western blot. Conclusion: The antiproliferative effect of DADS in CNE2 cell line is related to G₁ phrase arrest through decreasing expression levels of cyclin D1 and CDK4.