Chemotherapy of human choriocarcinoma transplanted to nude mice

Two human choriocarcinomas serially transplanted to athymic nude mice (BALB/c, nu/nu) were treated with intraperitoneal injections of methotrexate (MTX), actinomycin D (ACTD), and vinblastine (VLB) with doses per injection slightly smaller than LD10 in mice. Both ACTD and VLB significantly suppressed the growth of one tumor strain (SCH) but MTX did not. The growth of another tumor strain (CC-1) was not inhibited by either ACTD or VLB. In strain SCH, plasma HCG of tumor-bearing animals increased approximately in parallel with the growth of tumors in control and MTX-, ACTD-, and VLB-treated groups but the suppression of the hormone release was more marked in the ACTD-treated group. The results indicate that these two transplantable human tumors are useful models for the study of choriocarcinoma, particularly for therapeutic experiments.