Amplification and overexpression of the met gene in spontaneously transformed NIH3T3 mouse fibroblasts.
We have identified a class of transformed NIH3T3 mouse fibroblasts that arise at low frequencies in transfection experiments with DNA from both neoplastic and non-neoplastic cells and that may result from a low level of spontaneous transformation of NIH3T3 cells. DNA from the transformed cells was unable to transform NIH3T3 cells in a second cycle of transfection and, where examined, the cells showed no evidence for the uptake of the transfected DNA sequences. The results of Southern analyses demonstrate that a mouse homologue of the human met oncogene is amplified 4- to 8-fold in 7 of 10 lines of these transformed NIH3T3 mouse fibroblasts. The cells containing the amplified gene also exhibit at least a 20-fold overexpression of an 8.5-kb mRNA that is homologous to met. To test the hypothesis that met encodes a growth factor receptor, we examined the binding of platelet-derived growth factor, epidermal growth factor, insulin-like growth factor I and gastrin-releasing peptide to transformed and non-transformed NIH3T3 cells. The results show that there is no significant elevation of the binding of these growth factors to cells containing amplification and overexpression of met.
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D004262:DNA Restriction Enzymes; D005784:Gene Amplification; D006801:Humans; D051379:Mice; D008815:Mice, Inbred Strains; D009857:Oncogenes; D014158:Transcription, Genetic
D004262:DNA Restriction Enzymes