Objective: To set up a mdr1 multidrug resistant model of orthotopic transplantation of liver carcinoma in nude mice by intermittent abdominal chemotherapy.
Methods: The hepatocellular carcinoma cell line HepG2 was first cultured, then subcutaneous carcinoma was produced to form the tumor donor mice. An orthotopic mdr1 hepatoma was produced by implanting the tumor fragment subserosally to the mice liver, and intermittent chemotherapy with Pharmorubicin given to induce drug resistance. Physical examination, ultrasonography, spiral CT and laparotomy were used to examine the growth of the tumor. RT-PCR and SP method by the monoclonal antibody JSB-1 were adoped to detect the expression of mdr1-mRNA and p-gp protein.
Results: There was no mortality. The successful rate of tumor implantation is 88% (22/25), the successful rate of supplementary implantation was 100% (3/3), and the successful rate of induction of drug resistance was 80% (16/20). The expressions of mdr1-mRNA and p-gp in the Pharmorubicin group were 23 folds and 13 folds of the control group, respectively.
Conclusions: The nude mice mdr1 multidrug resistant model of orthotopic liver carcinoma were set up successfully, with its features similar to clinical cases. It would be helpful for the further study of the diagnosis and reversal strategy of the MDR phenomenon.