The Effect Of γ-TmT (γ-Tocopherol-Rich Mixture Of Tocopherols) On Esophageal Squamous Cell Carcinoma In Vitro

Objective:(1) To investigate the growth inhibitory and apoptotic effects of y-TmT, luteolin and sodium selenite (SS) alone or in combination on human esophageal cancer Eca-109 cells in vitro. (2) To evaluate the effects of y-TmT, luteolin and SS on the antioxidant enzyme activities of Eca-109 cells in vitro. (3) To study the effects of γ-TmT, luteolin and SS alone or in combination on the apoptotic proteins; Bcl-2, Bax and caspase-3 in human esophageal cancer Eca109 cells line in vitro.Methods:(1) 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to measure the growth inhibition of the Eca-109 cells. Morphological changes after treatment with y-TmT, luteolin and SS were observed by Inverted Phase Contrast Microscope. Cell apoptotic analysis was performed using flow cytometry. (2) Antioxidant enzymes activities such as glutathione peroxidase (GSH-Px), glutathione reductase (GR), catalase (CAT), and total superoxide dismutase (SOD), total antioxidant capacity (TAOC) and malondialdehyde (MDA) of Eca-109 cells with and without treatments with y-TmT, luteolin and SS alone or in combination were measured. (3) Apoptotic protein such as Bcl-2 and Bax were analyzed by quantitative real time polymerase chain reaction (qRT-PCR) and caspase-3 was analyzed by enzyme linked immunesorbent assay (ELISA).Results:(1) The results from MTT assay of y-TmT treatment showed dose and time dependent response on cell growth inhibition (p<0.05). Our results showed that the y-TmT significantly (p<0.05) induced apoptosis on Eca-109 cells. The combined results of y-TmT and luteolin on Eca-109 cells were higher than their alone effects (p<0.05). The MTT assay results of growth inhibition of on Eca-109 cells showed that the SS significantly (p<0.05) decreased the cell growth. Our results also found that the SS had higher effects on cell apoptosis. Similarly, the combined results of y-TmT and SS on Eca-109 cells showed that y-TmT and SS in combination significantly increased cell growth inhibition and induced cell apoptosis. (2) γ-TmT, luteolin and SS effects on antioxidant enzymes activities were significantly increased. (3) γ-TmT, luteolin and SS were significantly decreased the mRNA gene expression of Bcl-2 and increased the mRNA gene expression of Bax as well as caspase-3 levels in Eca-109 cells.Conclusion:γ-TmT, luteolin and SS are potent antioxidants and anticancer agents. Their use in combination may provide a novel strategy for preventing and treating esophageal cancer and other prevailing cancers. In future, these cancer therapeutic agents could provide useful insight on the synergistic mechanisms, and their potential application as a chemosensitizer in cancer therapy.