Methylsulfonylmethane induces G1 arrest and mitochondrial apoptosis in YD-38 gingival cancer cells

Abstract

Gingival squamous cell carcinoma is a rare form of cancer that accounts for less than 10% of all head and neck cancers. Targeted therapies with natural compounds are of interest because they possess high efficacy with fewer side-effects. Methylsulfonylmethane (MSM) is an organic sulfur-containing compound with anticancer activities. The main goal of this study was to induce proliferation inhibition and apoptosis in the metastatic YD-38 cell line. MSM upregulated expression of P21Waf1/Cip1 and P27Kip1 genes and down-regulated expression of cyclin D1 (CCND1) and CDK4. Moreover, treatment with MSM induced apoptosis and up-regulation of BAX in YD-38 cells. In accordance, the expression of the BCL-2 and BCL-XL, were inhibited, indicating the role of mitochondria in MSM-induced apoptosis. Analysis of mitochondrial integrity showed a loss of mitochondrial potential with an increased level of cytochrome c in the cytosol compared to mitochondria. Active CASPASE-3 (CASP3) was also observed, confirming that MSM-induced apoptosis is caspase-mediated.