孕酮对乳腺癌细胞中VEGF增殖和激活的膜起始效应。

Membrane-initiated effects of progesterone on proliferation and activation of VEGF in breast cancer cells.

作者信息

Neubauer H, Adam G, Seeger H, Mueck A O, Solomayer E, Wallwiener D, Cahill M A, Fehm T

机构信息

Department of Obstetrics and Gynecology, University of Tuebingen, Tuebingen, Germany.

出版信息

Climacteric. 2009 Jun;12(3):230-9. doi: 10.1080/13697130802635637.

DOI:10.1080/13697130802635637

PMID:19340614

Abstract

OBJECTIVE

Progesterone influences mammary gland development and probably breast cancer tumorigenesis and functions by regulating a broad spectrum of physiological processes. We investigated receptor membrane-initiated actions of progesterone in MCF-7 breast cancer cells via progesterone receptor membrane component 1 (PGRMC1).

DESIGN AND METHOD

The expression of PGRMC1 in breast cancer was verified by immune fluorescent analysis of paraffin sections. MCF-7 cells were transfected with PGRMC1 (wild type) or PGRMC1 variants. These cells were stimulated with a membrane-impermeable progesterone (P4) conjugate (P4-BSA-fluorescein isothiocyanate, P4-BSA-FITC, 10(-6) mol/l) or unconjugated progesterone (P4, 10(-6) mol/l) in the presence or absence of the progesterone receptor blocker RU-486 (10(-6) mol/l). Additionally, the effects on the expression of vascular endothelial growth factor A (VEGF-A) were determined using quantitative real-time polymerase chain reaction.

RESULTS

PGRMC1 is perinuclearly localized in breast cancer cells. Western Blot analysis suggests that PGRMC1 is phosphorylated at serine 180. MCF-7-PGRMC1 (S180A) cells show an approximately 35% increase in proliferation after incubation with P4-BSA-FITC compared to MCF-7 control and MCF-7-PGRMC1 (wild type) cells. This effect cannot be blocked by RU-486. P4 reduced proliferation of MCF-7-PGRMC1 cells by approximately 10% compared to untreated controls. P4-BSA-FITC treatment led to a roughly three-fold activation of VEGF-A gene expression compared to MCF-7 cells.

CONCLUSION

PGRMC1 is expressed in breast cancer tissue and mediates an RU-486-independent proliferative signal. It might also contribute to VEGF-induced neovascularization in tumor tissue. Thus, screening for PGRMC1 expression might be of interest to identify women with a higher expression of PGRMC1 and who might thus be susceptible for breast cancer development under hormone replacement therapy.

摘要

目的

孕酮通过调节多种生理过程影响乳腺发育，并可能影响乳腺癌的发生和功能。我们通过孕酮受体膜成分1（PGRMC1）研究了孕酮在MCF-7乳腺癌细胞中的受体膜起始作用。

设计与方法

通过石蜡切片的免疫荧光分析验证PGRMC1在乳腺癌中的表达。用PGRMC1（野生型）或PGRMC1变体转染MCF-7细胞。在存在或不存在孕酮受体阻滞剂RU-486（10⁻⁶mol/L）的情况下，用膜不可渗透的孕酮（P4）偶联物（P4-牛血清白蛋白-异硫氰酸荧光素，P4-BSA-FITC，10⁻⁶mol/L）或未偶联的孕酮（P4，10⁻⁶mol/L）刺激这些细胞。此外，使用定量实时聚合酶链反应测定对血管内皮生长因子A（VEGF-A）表达的影响。

结果

PGRMC1在乳腺癌细胞中呈核周定位。蛋白质印迹分析表明PGRMC1在丝氨酸180处被磷酸化。与MCF-7对照和MCF-7-PGRMC1（野生型）细胞相比，MCF-7-PGRMC1（S180A）细胞在与P4-BSA-FITC孵育后增殖增加约35%。这种作用不能被RU-486阻断。与未处理的对照相比，P4使MCF-7-PGRMC1细胞的增殖降低约10%。与MCF-7细胞相比，P4-BSA-FITC处理导致VEGF-A基因表达大约三倍的激活。