Cell yield and cell survival following chemotherapy of the B16 melanoma

Open Access
Publisher Website
Google Scholar
Abstract
Cell survival studies were described, using in vitro clonogenic assays, performed on the [mouse] B16 melanoma treated in situ with various cytotoxic agents. The effects of these agents on the yield of cells obtained by trypsinization was determined. In untreated tumors the mean cell yield was .apprx. 108/g, which is 20-30% of the cells actually present in the tissue. The plating efficiency was .apprx. 40%. Most agents rapidly affected cell yield and cell survival. For example, within 20-30 h, .gamma.-radiation and several alkylating agents reduced cell yield by about 40%. The cell yield change was associated with an increase in mean cell size. Cell yield was reduced even more (.apprx. 70%) by Vinca alkaloids. This large reduction was associated with extensive cell lysis, observed as an increase in the necrotic fraction of tumors from .apprx. 35% to 70%. Adriamycin, bleomycin and Ara-C .apprx. also produced a moderate reduction in cell yield (.apprx. 40%), but actinomycin D did not reduce cell yield and FU [5-fluorouracil] increased it by about 30%. Only .gamma.-radiation, cyclophosphamide, CCNU [1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea], BCNU [1,3-bis(2-chloroethyl)-1-nitrosourea] and melphalan produced more than a 90% reduction in cell survival, although there was a small but measurable reduction with all other agents except vinblastine, HN2 [nitrogen mustard] and actinomycin D.