Reversal of Multidrug Resistance in NPC HNE-1(200) Cell Line by Oxymatrine / 中国药房

ABSTRACT

OBJECTIVE:To study the reversal mechanism of oxymatrine on multidrug resistance in the NPC HNE-1(200) cell line. METHODS: The multidrug resistant HNE-1(200) subline was derived from an HNE-1 cell line after exposure to fractionated X-irradiation. The expression of P-gp was tested by immunocytochemical method and western blot and that of mdr1 mRNA was measured by RT-PCR. RESULTS: After 24-hour treatment with oxymatrine, both the immunocytochemical method and western blot showed a decrease in the expression of P-gp. However, RT-PCR measurement showed that the expression of mdr1 mRNA of HNE-1 and HNE-1(200) was nonsignficant. CONCLUSION: Oxymatrine can reverse the multidrug resistance of NPC HNE-1(200) cell line to some degree by down-regulating the expression of P-gp. However, this medicine did no effect on the expression of mdr1 mRNA, suggesting the up-regulation of the expression of P-gp is under the control of multiple mechanism.