Control of aromatase activity in breast cancer cells: the role of cytokines and growth factors.
The aromatase complex has a key role in regulating oestrogen formation in normal and malignant breast tissues. Using dexamethasone-treated fibroblasts, derived from breast tumours, breast tumour cytosol and breast tumour-derived conditioned medium (CM) markedly stimulate aromatase activity. The cytokine, interleukin-6 (IL-6) has been identified as a factor present in CM which is capable of stimulating aromatase activity. To examine whether IL-6 may have a role in vivo in regulating breast tissue aromatase activity, IL-6 production and aromatase activity in breast tumour and adipose tissue from breast quadrants were examined. In 5/6 breasts examined so far, aromatase activity was highest in adipose tissue in the breast quadrant containing the tumour or on which the tumour impinged. There was a significant correlation (P < 0.05, Kendall's rank correlation) between IL-6 production and aromatase activity in these breast tissues. It is concluded that IL-6 may have an important role in regulating aromatase activity in breast tissues.
Reed
M J
MJ
Unit of Metabolic Medicine, St Mary's Hospital Medical School, Imperial College of Science, Technology and Medicine, London, England.
Topping
L
L
Coldham
N G
NG
Purohit
A
A
Ghilchik
M W
MW
James
V H
VH
D000273:Adipose Tissue / Q000201:enzymology / Q000473:pathology; D001141:Aromatase / Q000378:metabolism*; D001943:Breast Neoplasms / Q000201:enzymology* / Q000473:pathology / Q000601:surgery; D017077:Culture Media, Conditioned; D003600:Cytosol / Q000201:enzymology; D003907:Dexamethasone / Q000494:pharmacology; D004815:Epidermal Growth Factor / Q000494:pharmacology; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000201:enzymology; D006133:Growth Substances / Q000494:pharmacology*; D006801:Humans; D007328:Insulin / Q000494:pharmacology; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D007375:Interleukin-1 / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D017077:Culture Media, Conditioned; D006133:Growth Substances; D007328:Insulin; D007375:Interleukin-1; D004815:Epidermal Growth Factor; D007334:Insulin-Like Growth Factor I; D003907:Dexamethasone; D001141:Aromatase