Studies on over-expression of aromatase in leiomyoma of the uterus and its application for conservative management

在这项研究中，我们详细描述了芳香化酶P450在平滑肌瘤中的表达，以确定原位雌激素在平滑肌瘤生长优势中的生理和病理作用。1）我们通过三种不同和互补的方法证明了芳香化酶P450在平滑肌瘤组织中的过度表达，与周围的子宫肌层相比：芳香化酶P45 O转录物的水平通过定量竞争RT-PCR进行定量。蛋白质的量通过使用平滑肌瘤组织的微粒体组分的Western印迹分析进行半定量。2）为了鉴定平滑肌瘤组织中表达芳香化酶P450的细胞类型，对组织样品和从新鲜平滑肌瘤组织中释放和培养的平滑肌瘤细胞进行免疫组织化学分析。3）为了确定内源性芳香化酶P450是否在平滑肌瘤细胞的生长促进中起作用，我们使用WST-1测定和胸苷掺入测定来评估用不同浓度的雌激素和雄激素处理的平滑肌瘤细胞的细胞W生长。我们证实平滑肌瘤细胞自身合成雌激素，雌激素通过自分泌/内分泌机制促进其生长。4）术前促性腺激素释放激素（GnRH）激动剂治疗显著抑制平滑肌瘤组织中芳香化酶P450的表达。体外实验表明，GnRH激动剂直接作用于平滑肌瘤细胞，降低芳香化酶的表达。GnRH激动剂对原位芳香化酶的这种直接抑制作用似乎有助于GnRH激动剂治疗期间平滑肌瘤的快速消退。

In the this study we characterized in detail the expression of aromatase P450 in leiomyomas to determine the physiological and pathological role of in situ estrogen in the growth advantage of leiomyomas.1) We demonstrated over-expression of aromatase P450 in leiomyoma tissues in comparison to the surrounding myometrium by three different and complementary methods: The levels of aromatase P45O transcripts were quantitated by quantitative competitive RT-PCR The amount of protein was semi-quantitated by Western blot analysis using microsomal fractions of leiomyoma tissues. Enzyme activity was measured by tritiated water-releasing assay using microsomal fractions.2) To identify a cell type that express aromatase P450 in leiomyoma tissues, immunohistochemical analysis was performed on the tissue samples and the leiomyoma cells that were released and cultured from the fresh leiomyoma tissues. Strong immunoreactivity was localized in the cytoplasm of leiomyoma cells.3) To determine whether endogenous aromatase P450 plays a role in the growth promotion of leiomyoma cells, we evaluated the cell W growth of leiomyoma cells treated with various concentration o of estrogens as well as androgens using a WST-1 assay and thymidine incorporation assay. We confirmed mat leiomyoma cells per se synthesize estrogen, which promotes their growth via an autocrine/intracrine mechanism.4) The expression of aromatase P450 in leiomyoma tissues was profoundly suppressed by preoperative gonadotrophin releasing hormone (GnRH) agonist therapy. In vitro experiment indicated that GnRH agonist acted directly on the leiomyoma cells to reduce the expression of aromatase. This direct inhibitory action of GnRH agonist on in situ aromatase seems to contributes to the rapid regression of leiomyoma during GnRH agonist therapy.