BRCA1 regulates progesterone receptors A and B protein expressions in breast cancer cells in vitro

• Published in: Nan fang yi ke da xue xue bao = Journal of Southern Medical University Vol. 28; no. 7; p. 1157
• Main Authors: Guo, Yin-xia, Zeng, Wei-sen, Liu, Ya-wei, Li, Yu-sheng, Lin, Jun, Xiong, Jing-bo, Luo, Shen-qiu
• Format: Journal Article
• Language: Chinese
• Published: China 01.07.2008
• Subjects: Blotting, Western; BRCA1 Protein - biosynthesis; BRCA1 Protein - genetics; Breast Neoplasms - genetics; Breast Neoplasms - metabolism; Breast Neoplasms - pathology; Cell Line, Tumor; Female; Gene Expression Regulation, Neoplastic; Humans; Receptors, Progesterone - biosynthesis; Receptors, Progesterone - genetics; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - biosynthesis; RNA, Messenger - genetics; RNA, Small Interfering - genetics; Transfection
• ISSN: 1673-4254

To study the regulatory role of BRCA1 in the expression of progesterone receptors A and B (PRA and PRB) in breast cancer cells. Breast cancer MCF-7 cells were transfected with pFlag-CMV2-BRCA1 wt plasmid containing a full-length BRCA1 cDNA or with BRCA1-specific siRNA via lipofectamine 2000 to induce overexpression or suppressed expression of BRCA1, respectively. Twenty-four hours after the transfection, the cells were incubated in fresh culture medium containing 100 nmol/L progesterone for 24 h. The total RNA extract or whole cell lysate was prepared for detecting BRCA1, PRA and PRB expressions using RT-PCR and Western blotting. The protein expressions of PRA and PRB were significantly decreased whereas their mRNA expressions remained unchanged in MCF-7 cells overexpressing BRCA1. In MCF-7 cells with BRCA1 knock-down, in contrast, the PRA and PRB protein expressions were markedly increased. In breast cancer cells, exogenous and endogenous BRCA1 can both down-regulate the expressions of PRA and PRB at the pro