Estradiol down-regulates CD36 expression in human breast cancer cells.
CD36 is a trans-membrane receptor that regulates apoptosis and angiogenesis in response to its ligand thrombospondin-1 (TSP-1). This study measures expression of CD36 and TSP-1 in breast cancer cell lines. Expression of TSP-1 was approximately 50-fold higher in the aggressive cell line MDA-MB-231 than in less aggressive MCF-7, BT-474, ZR-75 and T47-D cells. In contrast, MDA-MB-231 express 30 to 100-fold less CD36 than less aggressive cells. Hormone-dependent T47-D and MCF-7 cells down-regulate CD36 in response to estradiol, and anti-hormone ICI 182,780 block this effect. These results suggest that the estrogen receptors play a role in regulating CD36 expression and ICI 182,780 prevents loss of CD36 as a novel mechanism for its anti-estrogen effect in breast cancer cells.
Uray
Ivan P
IP
Department of Integrative Biology and Pharmacology, University of Texas Health Science Center, Houston, USA.
Liang
Yayun
Y
Hyder
Salman M
SM
D018931:Antineoplastic Agents, Hormonal / Q000494:pharmacology; D017209:Apoptosis; D015152:Blotting, Northern; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D018955:CD36 Antigens / Q000096:biosynthesis*; D002455:Cell Division; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000502:physiology*; D005260:Female; D000077267:Fulvestrant; D006801:Humans; D009389:Neovascularization, Pathologic; D012313:RNA / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019700:Thrombospondin 1 / Q000378:metabolism; D013997:Time Factors
D018931:Antineoplastic Agents, Hormonal; D018955:CD36 Antigens; D011980:Receptors, Progesterone; D019700:Thrombospondin 1; D000077267:Fulvestrant; D004958:Estradiol; D012313:RNA