Production of epithelial and mesenchymal tumours with rat liver cells transformed in vitro.
Epithelial-like cells originating from the livers of 10-day and 8-week-old BD rats were established in culture. The cells were treated in vitro for 1 or 4 weeks with dimethylnitrosamine (DMN) or N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Although some structural changes were observed in treated cells, it was not possible to score for morphological transformation in vitro. Newborn syngeneic rats were injected with 1.5-2 times 10(6) treated or 1.5-5 times 10(6) control cells at various times up to 38 weeks from the beginning of treatment with the carcinogen. Following the injection of DMN-treated cells, a total of 32 of the 42 injected rat developed tumours, of which 17 were epithelial, 10 carcinosarcomas and 5 fibrosarcomas. Following the injection of the MNNG-treated cells into 61 rats, a total of 30 tumours were observed, including 8 carcinomas, 9 carcinosarcomas and 13 fibroscarcomas. Tumours, mainly of the mesenchymal type, were also observed in rats inoculated with control cells but at a lower frequency. The observation observed in rats inoculated with control cells but at a lower frequency. The observation of mesenchymal tumours is attributed to the presence of a mixed population of epithelial and mesenchymal cells in the orginal culture.
D000818:Animals; D002296:Carcinosarcoma / Q000473:pathology; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000187:drug effects*; D002478:Cells, Cultured; D004128:Dimethylnitrosamine / Q000494:pharmacology*; D004847:Epithelial Cells; D004848:Epithelium / Q000187:drug effects; D005354:Fibrosarcoma / Q000473:pathology; D066298:In Vitro Techniques; D008099:Liver / Q000166:cytology; D008637:Mesenchymoma / Q000473:pathology; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology*; D009362:Neoplasm Metastasis; D009368:Neoplasm Transplantation; D009374:Neoplasms, Experimental; D009602:Nitrosamines / Q000494:pharmacology*; D009604:Nitrosoguanidines / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012513:Sarcoma, Experimental / Q000473:pathology; D014185:Transplantation, Isogeneic
D009602:Nitrosamines; D009604:Nitrosoguanidines; D008769:Methylnitronitrosoguanidine; D004128:Dimethylnitrosamine