Induction of mouse mammary tumours in a transplantation system by the sequential introduction of the myc and ras oncogenes.
A novel helper-free defective retrovirus containing the v-Ha-ras oncogene has been constructed and used to introduce the gene into primary mouse mammary epithelial cells already containing the v-myc oncogene. Transplantation of such doubly altered cells into cleared mammary fat pads led to the formation of mammary tumors within 6 to 8 weeks of transplantation. In a separate experiment, both oncogenes were simultaneously introduced to normal epithelium and once again tumours were formed. Neither oncogene alone gave a significant rate of tumour formation, although myc alone gave a reproducible hyperplasia as previously reported and ras alone gave occasional dysplastic or alveolar lesions. The results presented here demonstrate the progression of a normal cell through a hyperplastic intermediate to a tumour-forming cell in a versatile in vivo transplantation model.
Bradbury
J M
JM
Department of Pathology, University of Cambridge, UK.
Sykes
H
H
Edwards
P A
PA
D000818:Animals; D015152:Blotting, Northern; D015139:Blotting, Southern; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D004847:Epithelial Cells; D004848:Epithelium / Q000473:pathology; D005260:Female; D016259:Genes, myc; D011905:Genes, ras; D005822:Genetic Vectors; D008321:Mammary Glands, Animal / Q000166:cytology / Q000473:pathology; D008325:Mammary Neoplasms, Experimental / Q000235:genetics* / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D009924:Organ Culture Techniques; D051381:Rats; D015183:Restriction Mapping; D012190:Retroviridae / Q000235:genetics