Progesterone induces BRCA1 mRNA decrease, cell cycle alterations and apoptosis in the MCF7 breast cancer cell line.
(2005)
Journal - Anticancer research (Greece )
Abstract :
BACKGROUND: Inherited mutations of the BRCA1 gene are responsible for hereditary breast and ovarian cancer syndrome. However, little is known of how disruption of BRCA1 functions preferentially increases cancer risk in hormone-dependent organs. We aimed to study whether BRCA1 was regulated by progesterone in the MCF7 breast cancer cell line. MATERIALS AND METHODS: MCF7 breast cancer cells were incubated with 10(-4) or 10(-10) M progesterone for 24 or 48 hours. BRCA1 expression, proliferation and apoptosis were analysed. RESULTS: 10(-4) M progesterone decreased cell proliferation, cell cycle progression and induced apoptosis. In addition, BRCA1 and cyclin A mRNA decreased. In contrast, none of these effects were observed in MCF7 cells incubated with 10(-10) M progesterone. CONCLUSION: The down-regulation of BRCA1 in MCF7 cells incubated with 10(-4) M progesterone seems to be a consequence of cell cycle alterations rather than a direct effect of the hormone on BRCA1.
| ISSN : | 0250-7005 |
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| Mesh Heading : | Apoptosis BRCA1 Protein Breast Neoplasms Cell Cycle Cell Line, Tumor Cell Proliferation Cyclins Humans Progesterone RNA, Messenger Receptors, Estrogen Receptors, Progesterone drug effects biosynthesis metabolism pathology drug effects drug effects biosynthesis genetics genetics metabolism biosynthesis biosynthesis |
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| Mesh Heading Relevant : | genetics genetics pharmacology |
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Expression of BRCA1, HER-1 (EGFR) and HER-2 in sporadic breast cancer and relationships to other clinicopathological prognostic features.
(2005)
Journal - Anticancer research (Greece )
Abstract :
BACKGROUND: The BRCA1 caretaker gene is associated with poor prognostic features in hereditary breast cancer and may also play a role in sporadic breast cancer (SBC). HER-1 and HER-2 overexpression is associated with adverse prognosis in SBC. We studied whether BRCA1 expression was associated with HER1, HER2 and other prognostic features in SBC. PATIENTS AND METHODS: Fifty newly-diagnosed SBC patients were studied for prognostic features and immunohistochemical expressions of BRCA1, HER-1 and HER-2. RESULTS: Tumors were positive for BRCA1 in 26%, HER-1 in 32% and HER-2 in 20% of cases. Lack of BRCA1 expression was associated with node metastases and decreased estrogen receptor. HER-2 expression was associated with young age, HER-1, Ki67 and decreased hormone receptors. No correlation was observed between BRCA1 and HER-1 or HER-2. CONCLUSION: In SBC, the lack of BRCA1 expression was associated with poor prognostic features, but unrelated to HER-1 and HER-2. HER2 and HER-1 were, however, highly correlated.
| ISSN : | 0250-7005 |
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| Mesh Heading : | Adult Aged Aged, 80 and over BRCA1 Protein Breast Neoplasms Humans Immunohistochemistry Middle Aged Prognosis Receptor, Epidermal Growth Factor Receptor, erbB-2 genetics genetics pathology genetics genetics |
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| Mesh Heading Relevant : | biosynthesis metabolism biosynthesis biosynthesis |
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