Molecular Mechanism Of OrphaninFQ Combined With Adriamycin Reverse Multi-drug Resistance Of K562/ADM Cells

Objective:To investigate the molecular mechanism of OFQ combined with ADM reverse multi-drug resistance of K562/ADM cells, as well as the correlation with the expression of MDR1mRNA and P-glycoprotein(P-gp).Method:MTT method was used to test the proliferation ability of K562/ADM the treated with OFQ, ADM and the combination of them; Flow cytometry was performed to measure the cell apoptosis rate; Real time-PCR was applied to detect the MDR1mRNA expression; Western blot was used to check the P-gp expression.Results:K K562/ADM cells were treated with different concentration of OFQ(10-5-10-9mol/l) and ADM(5-40μg/mL), there were inhibitied on several levels, according to the concentration-inhibition ratio curve, oue research use non-cytotoxic dose10-7mol/l OFQ(IR<5%) and15μg/ml ADM (IC50was21μg/ml at72hours) as optimal concentration.2、OFQ(10-7mol/l) combined with ADM(15μg/mL) could significantly inhibit the cell proliferation of K562/ADM,compared with ADM group, date at48hours were statistically significant (P<0.05); The cell proliferation inhibition rates of ADM group are17.2%、19.5%、22.4%and32.3%, as well as the ADM+OFQ group were18.7%、22.4%、34.1%、35.8%at12h,24h,48h and72h respectively. Drug resistance reversal fold were1.09,1.15,1.41and1.11fold of12h,24h,48h and72h respectively, It was time related (r=0.97)and got the highest effect at48hours.3、Flow cytometry showed:Compared with ADM group, OFQ combined with ADM could markly raise the cells apoptosis percentage of K562/ADM (P<0.01); Drug resistance reversal fold were18.91,10.84,6.76and1.61of12h,24h,48h and72h respectively.4、Real time-qPCR diaplayed:MDR1mRNA expression was significantly different (P<0.01) between ADM alone and the combination of OFQ and ADM, while the decline of MDR1mRNA expression in ADM+OFQ group were time-dependent within48hour(r=0.91).5、Western blot showed:With times extends, the P-gp expression of ADM+OFQ group was gradually reduced(r=0.98), compared with ADM group, it was significantly difference (P<0.01). OFQ combined with ADM could reverse the multidrug resistance of K562/ADM, reversal fold were1.261,1.517,3.382,2.103respectively.Conclusion:1、OFQ combined with ADM can reverse the multi-drug resistance of K562/ADM in time-dependent manner, and48h is the best reverse time.2、 Molecular mechanism of OFQ combined with ADM reversing multi-drug resistance of K562/ADM may be related with the done reguiating the expression of MDR1mRNA and P-gp.