The EGF receptor (EGFR) is overexpressed in many human tumors implicating it in the pathogenesis of some cancers. To test the role of the EGFR in cancer, a retrovirus encoding the EGFR was constructed and shown to cause EGF dependent transformation of 3T3 cells. To study regulation of the EGFR gene, the promoter region was shown to contain many transcription factor binding sites including six Sp1 sites and sites for three other factors. Factor ETF1 stimulates EGFR transcription, has a Mr of 120 kilodaltons, and binds to region -230 to -250. Factor ETF2 stimulates both EGFR and SV40 transcription and binds to -120 to -145. EGF has been shown to raise EGFR RNA levels in KB cells. This effect appears to be due to an increase in EGFR RNA half life.
