Abstract: ObjectiveTo observe the apoptosis of breast cancer cells induced by small direct-current electric field (EF) and its related possible mechanism in expression of p21 and p16 genes.MethodsSmall direct-current EF was applied in human breast cancer cell line MCF7 in vitro and the effect of EF on apoptosis and expression of p21 and p16 important genes of breast cancer cells was observed.ResultsThe small direct-current EF had an obvious apoptosis inducing effect on breast cancer cells. A lot of cancer cells were sloughed from culture dish by 200 mV/mm of the EF strength. The number of the apoptotic cancer cells was gradually significantly increased and mRNA expressions of p21 and p16 genes were raised following the EF strength being up (P<0.01).ConclusionThe small direct-current EF has an obvious apoptosis inducing effect on breast cancer cells. It may be related with the expression of p21 and p16 genes.

Key words: breast neoplasm, direct-current electric field, gene