Study of orthotopic implantation of multidrug-resistance gastric carcinoma cell in nude mice

Objective To establish an orthotopic model of h uman multidrug-resistance(MDR)gastric carcinoma in the stomach wall of nude mice and investigate its dru g-resistance characteristics.Methods The human gastric carcinoma cell str ain SGC-7901and multidrug-resista nce gastric carcinoma cell strain SGC-7901/VCR were respectively transplanted into the stoma ch wall of two group nude mice.MTT assay was used to examine the drug-re sistance characteristic of tissue c ell of xenografts.The MDR gene expression was showed by means of RT-PCR technology.Results MTT assay showed IC 50 of the tissue cell of the resistance xenografts and its counterparts were 5.78mg /L and 0.98mg /L respectively.No difference was found between the orthotopic xen oplasms cell and their parent cell(1.01mg /L and 5.20mg /L).RT-PCR assay showed the MDR gene expression of the tissue cell of the resistance x enoplasms was positive and its counterpart was negative.Conclusion The human MDR gastric carcinoma cell orthotopic xenoplasms in nude mice provides a good animal model having the host organ's microenvir onment for the study of human MDR gastric carcinoma.