Effect of fractionated radiation on multidrug resistance in human ovarian cancer / 中华放射医学与防护杂志

ABSTRACT

Objective To investigate the effect of different subtypes of fractionated doses on multidrug resistance in ovarian cancer cells.Methods The human ovarian cancer cell lines SKOV3 and its drug-resistant subtype SKVCR were divided into four groups i.e., sham-irradiated, single dose (10 Gy),fractionated dose (2 Gy × 5 ) and multi-fractionated dose (1 Gy × 2 × 5).Cell sensitivity to vincristine(VCR),etoposide ( VP-16),pirarubicin (THP) and cisplatin (DDP) was measured by MTT assay.Western blot was applied to detect the expression of P-gp after irradiation.Results The doubling time of SKVCR was about 1.8-fold of that of SKOV3 cells.P-gp was expressed in SKVCR but not in SKOV3.IC50 values of SKVCR were higher than those of SKOV3.To SKOV3 cells,single dose irradiation decreased cell sensitivity to THP and DDP and fractionated irradiation decreased cell sensitivity to VCR,THP and VP-16.Multi-fractionated irradiation decreased cell sensitivity to VP-16.In SKVCR cells,all these irradiation treatments increased cell sensitivity to VCR and VP-16 but not to DDP.In addition,single and fractionated irradiation decreased P-gp expression in SKVCR cells.Conclusions Single,fractionated and multi-fractionated radiation induced chemotherapy resistance in SKOV3 cells,while reversed drug resistance to VCR and VP-16 in SKVCR cells.