Transformation of mouse mammary epithelial cells with the Ha- ras but not with the neu oncogene results in a gene dosage-dependent increase in transforming growth factor-α production

• Published in: FEBS letters 1989-07, Vol.250 (2), p.474-478
• Main Authors: Ciardiello, Fortunato, Hynes, Nancy, Kim, Nancy, Valverius, Eva M., Lippman, Marc E., Salomon, David S.
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Blotting, Northern; Cell Line, Transformed; Cell physiology; Cell transformation and carcinogenesis. Action of oncogenes and antioncogenes; Cell Transformation, Neoplastic - metabolism; Cells, Cultured; CM, conditioned medium; DMEM, Dulbecco's modified Eagle's medium; EGF, epidermal growth factor; Epithelial Cells; Epithelium - metabolism; FBS, fetal bovine serum; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation; Mammary Glands, Animal - cytology; Mammary Glands, Animal - metabolism; Mice; Molecular and cellular biology; Oncogene; Oncogene Protein p21(ras); Oncogene Proteins, Viral - genetics; Oncogene, neu; Oncogene, ras; Proto-Oncogene Proteins - genetics; Proto-Oncogenes; Receptor, ErbB-2; RIA, radioimmunoassay; RNA, Messenger - analysis; RRA, radioreceptor assay; TGFα, transforming growth factor-α; Transformation; Transforming growth factor-α; Transforming Growth Factors - biosynthesis; Viral Proteins - genetics
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(89)80779-3

An enhanced expression of transforming growth factor-α (TGFα) was demonstrated in two clones of NOG-8 mouse mammary epithelial cells, NOG-8 SR1 and NOG-8 SR2, that have been transformed by a v-Ha- ras oncogene. The amount of TGFα production in NOG-8 SR1 and NOG-8 SR2 cells was dependent on the level of p21 ras expression in these clones, which directly correlated with their cloning efficiency in soft agar. There was also a decrease in the number of epidermal growth factor (EGF) receptors on the NOG-8 SR1 and NOG-8 SR2 cells that is proportional to the amount of TGFα secreted. These effects were specific for ras because neu-transformed NOG-8 cells grew in soft agar at a comparable level to NOG-8 SR2 cells yet did not show any increase in TGFα production or change in EGF receptor expression.