Fibroblast-dependent tumorigenicity of melanoma xenografts in athymic mice.
Two human melanoma cell lines, UCT-Mel 2 and UCT-Mel 3, were invariably tumorigenic in nude mice when inoculated s.c. in doses of 10(6) cells or higher; 10(5) cells or less did not give rise to tumours. In this report we show that otherwise sub-tumorigenic inocula developed into vigorously growing tumour xenografts when co-inoculated with normal fibroblasts. Fibroblasts derived from adult, neonatal or embryonic tissues all functioned as complementing cells, as did cells of human or murine origin. There was, however, a requirement for complementing cell viability, since ethanol-killed fibroblasts were inefficacious. The fibroblast effect was dose-dependent and was not observed if injections of fibroblasts and melanoma cells were separated anatomically or temporally. We have shown, by titrating admixtures of melanoma cells and fibroblasts, that fibroblasts are, in quantitative terms, more efficacious than melanoma cells as complementing cells. The system we describe provides a useful model for the study of stromal-cell regulation of tumour growth.
Gärtner
M F
MF
South African Medical Research Council Human Cell Biology Research Unit, Department of Clinical Science and Immunology, University of Cape Town.
Wilson
E L
EL
Dowdle
E B
EB
D000818:Animals; D002452:Cell Count; D003470:Culture Media; D000431:Ethanol / Q000494:pharmacology; D005347:Fibroblasts / Q000187:drug effects / Q000502:physiology* / Q000637:transplantation; D006801:Humans; D007700:Kinetics; D008546:Melanoma, Experimental / Q000473:pathology*; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D014407:Tumor Cells, Cultured
D003470:Culture Media; D000431:Ethanol