| Objective: To investigate whether oxymatrine(OM)can affect the drug resistance of xenograft tumors of HepG2/ADM drug-resistant hepatocellular carcinoma cell line by inhibiting the expression of Mi R-181 a in vivo,and study the possible mechanism.Methods: HepG2 / ADM cells from human hepatoma cells were used to inoculate underarms of nude mice to create a subcutaneous xenograft model in nude mice.42 female nude mice were randomly divided into 6 groups(7 mice per group): miR-181 a mimic group(50μg/ml),oxymatrine group(100mg/kg),oxymatrine+miR-181 a mimic group(100mg/kg+50μg/ml),adriamycin(ADM)group(6mg/kg),miRNA mimic NC group(50μg/ml),control group(PBS 50μg/ml),0.1ml tail vein injection per nude mouse.Injection every two days,after 18 days of drug intervention,the tumor was taken out,and the tumor volume was calculated by formula.Hematoxylin-eosin staining(HE)method was used to observe the cytopathic condition of tissues.Western blot(WB)and immunohistochemistry were used to detect the expression of Bim,a target protein of miR-181 a,and P-gp,a drug resistance index.Quantitative real-time quantitative PCR(q PCR)was used to detect the expression of Bim-related genes BCL2L11,P-gp-related drug resistance genes ABCB1 and miR-181 a.Results:(1)15 days after HepG2 / ADM inoculation,the model was successfully established,and the tumor formation rate of nude mice was 100%.(2)After 18 days of intervention,there was no significant difference between the adriamycin group,the controlgroup,and the miRNA mimic NC group(P> 0.05),and the differences between the other groups were statistically significant(P <0.05),miR-181 a mimic group has the strongest effect on tumor growth promotion,followed by the effect of oxymatrine + miR-181 a mimic group,and the effect of oxymatrine group on tumor growth is obvious.Adriamycin alone has a poor inhibitory effect on xenograft tumors.(3)HE staining results showed that adriamycin was basically ineffective against human liver cancer resistant cell line HepG2 / ADM,oxymatrine could promote tumor tissue necrosis,and miR-181 a mimic could inhibit tumor tissue necrosis.(4)Immune group The results of chemical analysis and western blot showed that the expression of Bim protein was highest in the oxymatrine group.The expression of Bim protein in miR-181 a mimic group and oxymatrine+miR-181 a mimic group was significantly reduced(P <0.05);miR-181 a mimic group P-gp protein expression was highest,followed by oxymatrine+miR-181 a mimic group and adriamycin group,P-gp protein expression in the oxymatrine group was significantly reduced(P <0.05).(5)Real-time quantitative PCR results showed that BCL2L11 m RNA expression was highest in the oxymatrine group,and the expression of BCL2L11 m RNA in miR-181 a mimic group and oxymatrine+miR-181 a mimic group was significantly reduced(P <0.05);ABCB1 m RNA expression was highest in the miR-181 a mimic group,followed by oxymatrine + miR-181 a mimic group and adriamycin group,ABCB1 m RNA expression was lowest in the oxymatrine group(P <0.05);miR-181 a expression was highest in miR-181 a mimic group,followed by oxymatrine+miR-181 a mimic group and adriamycin group,miR-181 a expression was lowest in the oxymatrine group(P<0.05).Conclusion:(1)Oxymatrine can inhibit the growth of HepG2 / ADM resistant nude mice xenografts and improve the general situation of resistant nude mice.(2)miR-181 a increase the expression of ABCB1 m RNA and P-gp protein in nude mice with HepG2 / ADM-resistant xenograft tumors.The mechanism may be related to the down-regulation of Bim protein expression.(3)Oxymatrine reduce the expression of ABCB1 m RNA and P-gp protein in nudemice with HepG2 / ADM-resistant xenograft tumors.The mechanism may be to increase the expression of Bim protein by inhibiting the expression of miR-181 a.Thereby activating the mitochondrial apoptotic pathway and promoting tumor cell apoptosis to reverse the multidrug resistance of liver cancer. |
PDF Full Text Request