The Research Of Oxymatrine To Reverse The Multidrug Resistance Of Human Hepatocellular Carcinoma HepG2/ADM Cells

Objective: To explore the reversal effect of multidrug resistance ofoxymatrine on human hepatocellular carcinoma drug-resistant cell lineHepG2/ADM in vitro and its potential mechanism.Methods: To culture human hepatocellular carcinoma cell line HepG2andhuman hepatocellular carcinoma drug-resistant cell line HepG2/ADM in vitro;MTT assay was used to test not only the restrained effect of oxymatrine onHepG2cell line and HepG2/ADM cell line, but also the multidrug resistance ofHepG2/ADM cell line and its oxymatrine interventional change ofchemotherapeutic drugs sensitivity; Flow cytometry (FCM) was used to detectthe influence of oxymatrine on the apoptosis of HepG2/ADM cells; Real-timefluorescence quantitative PCR was used to detect the change of oxymatrineeffecting on the expression of ABCB1gene in HepG2/ADM cells; FCM wasused to test the change of oxymatrine effecting on P-glycoprotein expression ofthe surface of cytomembrane in HepG2/ADM cells.Results:1. Oxymatrine(OM) with concentration lower than0.5mg/mL had no apparent cytotoxic effects on the HepG2，HepG2/ADM cell line and thegrowth inhibitory rates of cell lines are lower than10%.2.The half-maximalinhibitory concentration (IC50) value of Adriamycin(ADM) in HepG2andHepG2/ADM cell lines were respectively0.42mg/L and11.56mg/L, theresistance indexes were27.52; after the treatment of OM, the IC50of ADM inHepG2/ADM cell line decreased to3.14mg/L, and the reversal multiple wasabout3.68times. The IC50of Cisplatin (CDDP) in HepG2and HepG2/ADMcell lines were respectively3.29mg/L and18.08mg/L, the resistance indexeswere5.50; after the treatment of OM, the IC50of CDDP in HepG2/ADM cellline significantly decreased to6.41mg/L, the reversal multiple was about1.95times. The IC50of5-FU(5-Fluorouracil) in HepG2and HepG2/ADM cell lineswere respectively7.94mg/L and34.83mg/L, the resistance indexes were4.39;after the treatment of OM, the IC50of5-FU in HepG2/ADM cell line decreasedto17.17mg/L,the reversal multiple was about2.03times.3. After the OMtreatment with the concentration at0.5mg/mL on HepG2/ADM cells for24,48,and72hours, the early cell apoptosis rates of the HepG2/ADM cells wereincreased gradually along with the extended time of treatment, comparing withthe control group(1.77%±0.25%vs0.50%±0.10%,2.53%±0.15%vs0.63%±0.06%,3.83%±0.42%vs0.66%±0.06%,all P＜0.05).4. Comparing with the negativecontrol, OM with the concentration at0.5mg/mL can down-regulate theexpression of related genes ABCB1of drug resistance after the treatment onHepG2/ADM cells for48hours.5. Comparing with the negative control, OMwith the concentration at0.5mg/mL can down-regulate the expression of P-gpafter the treatment on HepG2/ADM cells for48hours, but still higher than the group of HepG2cells(21.50%±1.08%vs40.83%±0.35%,21.50%±1.08%vs10.36%±0.60%，P＜0.01).Conclusions:1.Oxymatrine(OM) can inhibite the proliferation of thehepatocellular carcinoma cell line HepG2and drug-resistant cell lineHepG2/ADM.2. OM is able to everse multidrug resistance of the hepatocellularcarcinoma drug-resistant cell line HepG2/ADM in vitro.3.The possiblemechanisms of the reversing effect of OM on the multidrug resistance may berelated to the down-regulated expression levels of ABCB1and P-gp and thepromotion of cell early apoptosis after oxymatrine treatment.