N-myc oncogene enhances mitogenic responsiveness of diploid human fibroblasts to growth factors but fails to immortalize.

摘要: The N-myc gene is amplified in several types of human tumors. To assess the role transformation normal cells, we transfected an expression vector into diploid fibroblasts. Transfected clones were isolated and found to express at levels similar those seen a tumor cell line (neuroblastoma LA-N-1) which contains gene. level decreased as senesced. Clones expressing had increased saturation density altered morphology but did not have extended lifespan. Under low serum conditions, neither nor control cells showed anchorage-dependent growth. compared determine if different growth factors would affect ability grow soft agarose. agarose supplemented with epidermal factor (EGF) or transforming factor-alpha (TGF-alpha). However, grew 2.8- 18-fold higher response basic fibroblast (bFGF) 5.5- 55-fold platelet-derived B-chain homodimer (PDGF-BB).