Objective      To investigate the effect of albendazole (ABZ) on the chemoresistance of cisplatin-resistant human ovarian cancer SKOV-3/DDP cells by inhibiting P-glycoprotein (P-gp) expression.       Method      The effect of ABZ on the proliferation of SKOV-3/DDP cells was detected by methyl thiazolyl tetrazolium (MTT) colorimetry. According to the inhibition concentrations (IC) of 0%

25%

50% and 75%

the cells wer

e then divided into 4 groups including a control group

an IC

25

group

an IC

50

group and an IC

75

group. Moreover

each group was divided into three subgroups (12

24 and 36 h) based on the ABZ treatment time. P-gp expression was determined by flow cytometry. The proliferation of SKOV-3/DDP cells was detected by MTT colorimetry after the treatment with ABZ combined and sequential with cisplatin (DDP)

epirubicin (EPI) and 5-fluorouracil (5-Fu).       Results      The expression of P-gp was decreased by ABZ in a dose- and time-dependent manner. Both combined and sequential with ABZ could decrease the effective concentrations of DDP

EPI and 5-Fu to SKOV-3/DDP cells in a dose- and time-dependent manner

and the effect of combination was better than that of sequential treatment.       Conclusion      Through down-regulating the expression of P-gp in SKOV-3/DDP cells

ABZ can increase the sensitivity of SKOV-3/DDP cell to DDP

EPI and 5-Fu

and reverse its chemoresistance.