Abstract

Development of drug resistance in tumors during treatment is a major factor limiting the clinical use of anticancer agents. When tumor cells acquire resistance to anticancer drug, they show cross-resistance to other antitumor agents. In the present study, SNU-1 cell was induced adriamycin 10-7 drug resistance, SNU-1/ADR, in vitro culture system. We got the doubling time and number for viability test during 96 hours by MTT assay. To investigate the cross resistance of various anticancer drugs in human stomach cancer cell SNU-1 and SNU-1/ADR, We compared IC50 (drug concentration of 50% reduction) and the relative resistance (RR). SNU-1/ADR was expressed multidrug resistant with vinblastine (RR;>31.62), vincristine (RR;29.50), dactinomycin (RR;21.37), epirubicin (RR;17.78), daunorubicin (RR;14.12), adriamycin (RR;7.76), and etoposide (RR;4.46), and other drugs, 5-fluorouracil, cisplatin, cyclophosphamide, methotrexate, and calarubicin, have not cross resistant with adriamycin. There was double minute chromosome in SNU-1/ADR by karyotyping although this change was not seen in SUN-1.