Induction of multidrug resistance in human breast cancer cells by exposure to chemotherapeutic drugs in vitro / 中国药理学通报

ABSTRACT

Aim To investigate the effect of exposure to high or low concentration chemotherapeutic drugs on multidrug resistance of human breast cancer cell MDA-MB-231.Method MDA-MB-231 was treated with high dose of adriamycin and paclitaxel or with low concentration of paclitaxe.SRB assay was used to determine the IC50 and RF.HE assay was used to evaluate the cellular morphology.The variations of P-gp and MDR1 were analyzed by immunocytochemistry and RT-PCR respectively.Results Cells survived only after treated with high dose of paclitaxel (MDA-MB-231/a).SRB assay showed that the growth rate of MDA-MB-231/a was the same as that of parent MDA-MB-231/w.The IC50 of the cells(MDA-MB-231/b)treated with low concentration of paclitaxel to several chemotherapeutic drugs was a little higher than that of MDA-MB-231/w.Immunocytochemistry showed that there was no difference between MDA-MB-231/a and MDA-MB-231/w in the expression of P-gp while the P-gp expression was a little higher in MDA-MB-231/b.RT-PCR assay showed that the MDR1 gene was over-expressed in MDA-MB-231/b.Conclusions The multidrug resistance cell lines can not be derived from MDA-MB-231/w by high dose of chemotherapeutic drugs.Induction of multidrug resistance response to chemotherapeutic drugs is related with transient exposure to low concentration of paclitaxel and this may be a way to establish the multidrug resistance model of MDA-MB-231 cells.