The growth promoting effect of transforming growth factor-alpha in human breast cancer cell lines.
Two human breast cancer cell lines, BT-20 and ZR-75-1, were examined with the aim of the elucidating the pathological roles of human transforming growth factor (TGF)-alpha in breast cancers. The TGF-alpha receptor was found to be present in both cell lines. A clonogenic assay revealed that concentrations of TGF-alpha greater than 10(10) M induced a significant increase in colony formation, indicating TGF-alpha to be a breast cancer cell growth factor. Northern blot analysis revealed, moreover, that both cell lines expressed TGF-alpha mRNA. Taking these observations together, it is reasonably possible to assume that TGF-alpha is an autocrine growth factor for breast cancer cells. Although it has been proposed that TGF-alpha could be an epidermal growth factor (EGF) superagonist with regard to its colony formation stimulating activity, the present study demonstrated the colony formation stimulating activities of TGF-alpha and EGF not to be all that much different in the two breast cancer cell lines.
Kuranami
M
M
Growth Factor Division, National Cancer Center Research Institute, Tokyo.
Yamaguchi
K
K
Asanuma
F
F
Suzuki
M
M
Abe
K
K
D000818:Animals; D015152:Blotting, Northern; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology*; D004815:Epidermal Growth Factor / Q000378:metabolism / Q000494:pharmacology; D005260:Female; D005347:Fibroblasts / Q000187:drug effects; D006801:Humans; D008970:Molecular Weight; D012333:RNA, Messenger / Q000032:analysis; D012334:RNA, Neoplasm / Q000032:analysis; D051381:Rats; D015291:Transforming Growth Factors / Q000378:metabolism / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D012333:RNA, Messenger; D012334:RNA, Neoplasm; D004815:Epidermal Growth Factor; D015291:Transforming Growth Factors