Study on ascorbic acid enhancing arsenic trioxide to induce apoptosis in cervical cancer HeLa cells

Objective To study whether ascorbic acid can enhance arsenic trioxide to induce apoptosis and to inhibit telomerase activity in cervical cancer HeLa cells.Methods After HeLa cells were treated with various concentrations of As_(2)O_(3) plus 250 μmol·L~(-1) ascorbic acid,effects of As_(2)O_(3 )and ascorbic acid on survival and apoptosis of HeLa cells were determined by light microscope,MTT assay,flow-cytometric analysis.Telomerase activity in HeLa cells was determined by TRAP?ELISA.Results There was no marked effect on the survival of HeLa cells after the cells treated by 1 μmol·L~(-1) As_(2)O_(3.)However,after 1 μmol·L~(-1) As_(2)O_(3)plus 250 μmol·L~(1) ascorbic acid treated HeLa cells,significant growth inhibition and apoptosis characteristics were found.As to the higher concentrations of As_(2)O_(3)(2,5,10 μmol·L~(-1)),the apoptosis rate of HeLa cells treated by(As_(2)O_(3))plus ascorbic acid was higher than that of HeLa cells treated by As_(2)O_(3)alone and apoptosis characteristics were earlier.Meanwhile,there was more marked telomerase inhibition following to As_(2)O_(3)plus 250?μmol·L~(-1) ascorbic acid treatment than As_(2)O_(3)alone.Conclusion Ascorbic acid enhances arsenic trioxide to induce apoptosis in HeLa cells,which is related to its inhibiting telomerase activity in HeLa cells.