The cytostatic effects of alpha-interferon may be mediated by transforming growth factor-beta.
There is some evidence to suggest that transforming growth factor-beta (TGF-beta) mediates the cytostatic effects of the anti-oestrogen tamoxifen. In this study we have demonstrated that alpha-interferon has a significant anti-proliferative effect on the oestrogen receptor-positive human breast cancer cell line ZR-75. There is decreased phenotypic expression of the oestrogen receptors (to about 30% of control values) and increased TGF-beta mRNA. Under the growth conditions used here, ZR-75 cells had approximately 5800 TGF-beta binding sites per cell, with an apparent dissociation constant of 70 pm, and we have shown that the anti-proliferative effects of alpha-interferon can be reduced by 60% by co-treating the cells with a TGF-beta polyclonal antibody. The cytostatic effects of alpha-interferon may therefore be mediated by TGF-beta in this human breast cancer cell line.
Kerr
D J
DJ
Beatson Institute for Cancer Research, Glasgow.
Pragnell
I B
IB
Sproul
A
A
Cowan
S
S
Murray
T
T
George
D
D
Leake
R
R
D000906:Antibodies / Q000276:immunology; D000970:Antineoplastic Agents; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology / Q000648:ultrastructure; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology* / Q000627:therapeutic use; D007457:Iodine Radioisotopes; D010641:Phenotype; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D015291:Transforming Growth Factors / Q000276:immunology / Q000378:metabolism / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000187:drug effects
D000906:Antibodies; D000970:Antineoplastic Agents; D007457:Iodine Radioisotopes; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D015291:Transforming Growth Factors; D007371:Interferon-gamma