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In post-menopausal women, intra-mammary estrogen, which is converted from extra-ovarian estrone (E1), promotes the growth of breast cancer. Since the aromatase inhibitor letrozole does not suppress 17β-estradiol (E2) production from E1, high intra-mammary E1 concentrations impair letrozole''s therapeutic efficacy. Progesterone receptor membrane component 1 (Pgrmc1) is a non-classical progesterone receptor associated with breast cancer progression. In the present study, we introduced a Pgrmc1 heterozygous knockout (hetero KO) murine model exhibiting low Pgrmc1 expression, and observed estrogen levels and steroidogenic gene expression. Naïve Pgrmc1 hetero KO mice exhibited low estrogen (E2 and E1) levels and low progesterone receptor (PR) expression, compared to wild-type mice. In contrast, Pgrmc1 hetero KO mice that have been ovariectomized (OVX), including letrozole-treated OVX mice (OVX-letrozole), exhibited high estrogen levels and PR expression. Increased extra-ovarian estrogen production in Pgrmc1 hetero KO mice was observed with the induction of steroid sulfatase (STS). In MCF-7 cell, letrozole suppressed PR expression, but PGRMC1 knockdown increased PR and STS expression. Our presented results highlight the important role of Pgrmc1 in modulating estrogen production when ovary-derived estrogen is limited, thereby suggesting a potential therapeutic approach for letrozole resistance.  相似文献   
3.
Estrogen is an important hormone for health in both genders. It is indispensable to glucose homeostasis, immune robustness, bone health, cardiovascular health, and neural functions. The main way that estrogen acts in the cells is through estrogen receptors (ERs). The presence of specific estrogen receptors is required for estrogen to have its characteristic ubiquitous action in almost all tissues. Estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) are the major isoforms of estrogen that are highly specific in humans and enable selective hormonal actions in different tissues. This article reviews some of the observed estrogen actions and effects in different tissues and cells through these specific receptors. This ubiquitous, almost ordinary hormone may reveal itself as a significant factor that helped us to better understand the complexity of the human immune system response against respiratory infections, including the COVID-19, and especially in the current state of this painful pandemic.  相似文献   
4.
目的:通过生物信息学方法探讨雌激素受体α(ESRRA)在肺癌发生发展中的作用。方法:利用UALCAN在线平台对人肺癌组织(包括肺腺癌与肺鳞癌)和癌旁正常肺组织中ESRRA基因的表达变化进行分析,并利用Kaplan-Meier Plotter数据库对肺癌中ESRRA及其相关基因的表达进行生存分析。利用GEPIA2在线平台获得与ESRRA表达模式相似的前50个基因,在GeneMANIA在线平台上构建这50个基因编码的蛋白质-蛋白质的相互作用网络,并通过DAVID数据库对该50个基因群进行GO分析和KEGG通路富集。通过TIMER 2.0在线平台分析肺癌组织中ESRRA与富集在氧化磷酸化通路中核心基因表达水平的相关性。利用Western blot法验证ESRRA蛋白在肺癌细胞系中的表达水平。结果:与癌旁正常肺组织相比,ESRRA在肺癌组织中高表达(P<0.01),ESRRA表达水平高的肺癌患者显示出较差的预后(P<0.01)。与ESRRA表达模式相似的前50个基因主要富集在氧化磷酸化通路,包括ATP5B、ATP5G3、COX5A、COX8A、SDHD、UQCRC1UQCRC2。其中ATP5B、COX8AUQCRC1在肺癌组织中的表达水平与ESRRA的表达呈正相关(P<0.05)。ATP5B、ATP5G3、COX5A、COX8A、SDHD、UQCRC1UQCRC2在肺癌组织中均高表达,ATP5B、ATP5G3、COX5A、COX8A表达水平高和SDHD表达水平低的肺癌患者均显示出较差的预后(P<0.01)。Western blot验证结果显示,与正常人支气管上皮16HBE细胞相比,ESRRA蛋白的相对表达水平在肺腺癌NCI-H1975细胞和肺鳞癌SW900细胞中均高表达(P<0.01)。结论:ESRRA介导氧化磷酸化通路中ATP5BCOX8A的表达改变引起能量代谢紊乱可能是其促进肺癌发生和导致肺癌不良预后的原因之一。  相似文献   
5.
目的基于下丘脑-垂体-卵巢轴(hypothalamus-pituitary-ovary axis,HPOA)探讨藏药二十五味鬼臼丸对去卵巢大鼠骨质疏松的影响。方法将40只SD雌性未孕大鼠随机分为假手术组、模型组、雌二醇组、二十五味鬼臼丸组,每组10只。除假手术组仅摘取卵巢旁同样大小的脂肪块,其余3组大鼠均摘除双侧卵巢建立绝经后骨质疏松症(postmenopausal osteoporosis,PMOP)大鼠模型。手术1周后开始给药处理,雌二醇组ig0.1mg/kg戊酸雌二醇,二十五味鬼臼丸组ig441mg/kg二十五味鬼臼丸,假手术组和模型组ig等体积蒸馏水,1次/d,连续12周后,ELISA法检测血清雌二醇、黄体生成素(luteinizing hormone,LH)、卵泡刺激素(follicle stimulating hormone,FSH)、促性腺激素释放激素(gonadotropin releasing hormone,GnRH)水平;RT-PCR检测下丘脑、垂体、左侧股骨远端雌激素受体α(estrogen receptorα,ERα)、雌激素受体β(estrogen receptorβ,ERβ)m RNA表达;免疫荧光染色法检测下丘脑、垂体和右侧股骨远端ERα、ERβ蛋白表达;HE染色法观察大鼠右侧股骨远端组织形态变化;Micro-CT检测右侧股骨远端微结构的改变。结果藏药二十五味鬼臼丸能显著降低大鼠体内血清LH、FSH、GnRH水平(P0.05、0.01),并在HPOA轴中显著性上调下丘脑及垂体ERαm RNA及蛋白表达(P0.01),同时显著性上调股骨ERβm RNA及蛋白表达(P0.01),并能显著回调大鼠股骨密度及骨微结构参数(P0.01)。结论藏药二十五味鬼臼丸可有效防治PMOP,其机制可能与药物直接作用骨组织雌激素受体或作用HPOA轴靶器官相关雌激素受体后,通过改变体内性激素的水平间接调控骨代谢有关。  相似文献   
6.
BackgroundAs more patients with early-stage breast cancer receive neoadjuvant endocrine therapy (NET), there is a need for reliable biomarkers that can identify patients with HR+ HER2- tumors who are likely to benefit from NET. NBRST (NCT01479101) compared the prognostic value of the 70-gene risk classification and 80-gene molecular subtyping signatures with conventional pathological classification methods in response to neoadjuvant therapy. We evaluated the association of these signatures with clinical response and 5-year outcome of patients treated with NET.Methods1091 patients with early-stage breast cancer scheduled to receive neoadjuvant therapy were prospectively enrolled into NBRST, and a sub-analysis of 67 patients treated with NET was performed. Patients received standard of care genomic testing using the 70-gene and 80-gene signatures and were treated with NET, per physician's discretion. The primary endpoint was pathologic partial response (pPR) and secondary endpoints were distant metastasis-free survival (DMFS) and overall survival (OS). Clinical benefit was defined as having a pPR or stable disease (SD) with NET.ResultsOverall, 94.4% of patients with genomically (g) Luminal A-Type (50.0% pPR and 44.4% SD) and 95.0% with Luminal B-Type tumors (55.0% pPR and 40.0% SD) exhibited clinical benefit. At 5 years, patients with gLuminal B tumors had significantly worse DMFS (75.6%, 95% CI 50.8–89.1) than patients with gLuminal A (91.1%; 95% CI 74.8–97.1; p = 0.047), with a similar trend for OS, albeit not significant (81.0%, 95% CI 56.9–92.4 and 91.1%, 95% CI 74.8–97.1, respectively; p = 0.13).ConclusionsGenomic assays offer a broader understanding of the underlying tumor biology, which adds precision to pathology as a preoperative risk classifier. Patients with 70-gene signature Low Risk, gLuminal A tumors treated with endocrine therapy alone have excellent 5-year outcomes. Most patients with genomically-defined Luminal A- and B-Type tumors respond well to NET, suggesting these patients may be safely treated with NET, while those with gLuminal B tumors will also require post-operative chemotherapy or CDK4/6 inhibitors to improve long-term outcomes. Overall, these findings demonstrate that genomic classification, defined by the combined 70- and 80-gene signatures, is associated with tumor response and prognostic of long-term outcomes.  相似文献   
7.
Adiponectin is the major adipocytes-secreted protein involved in obesity-related breast cancer growth and progression. We proved that adiponectin promotes proliferation in ERα-positive breast cancer cells, through ERα transactivation and the recruitment of LKB1 as ERα-coactivator. Here, we showed that adiponectin-mediated ERα transactivation enhances E-cadherin expression. Thus, we investigated the molecular mechanism through which ERα/LKB1 complex may modulate the expression of E-cadherin, influencing tumor growth, progression and distant metastasis. We demonstrated that adiponectin increases E-cadherin expression in ERα-positive 2D and higher extent in 3D cultures. This occurs through a direct activation of E-cadherin gene promoter by ERα/LKB1-complex. The impact of E-cadherin on ERα-positive breast cancer cell proliferation comes from the evidence that in the presence of E-cadherin siRNA the proliferative effects of adiponectin is no longer noticeable. Since E-cadherin connects cell polarity and growth, we investigated if the adiponectin-enhanced E-cadherin expression could influence the localization of proteins cooperating in cell polarity, such as LKB1 and Cdc42. Surprisingly, immunofluorescence showed that, in adiponectin-treated MCF-7 cells, LKB1 and Cdc42 mostly colocalize in the nucleus, impairing their cytosolic cooperation in maintaining cell polarity. The orthotopic implantation of MCF-7 cells revealed an enhanced E-cadherin-mediated breast cancer growth induced by adiponectin. Moreover, tail vein injection of MCF-7 cells showed a higher metastatic burden in the lungs of mice receiving adiponectin-treated cells compared to control. From these findings it emerges that adiponectin treatment enhances E-cadherin expression, alters cell polarity and stimulates ERα-positive breast cancer cell growth in vitro and in vivo, sustaining higher distant metastatic burden.  相似文献   
8.
The WHI found an unexpected reduced breast cancer risk in women using CEE alone. We hypothesized CEE alone induces estrogen hydroxylation along the 2-pathway rather than the competing 16-pathway, a pattern linked to reduced postmenopausal breast cancer risk. One thousand eight hundred and sixty-four women in a WHIOS case–control study of estrogen metabolism and ovarian and endometrial cancer were studied of whom 609 were current E + P users (351 used CEE + MPA), while 272 used E alone (162 used CEE). Fifteen EM were measured, and analyses were conducted for each metabolite, hydroxylation pathway (2-, 4-, or 16-pathway) and ratios of pathway concentrations using inverse probability weighted linear regression. Compared to E + P users, all EM were higher in E alone users (significant for unconjugated estrone, total/conjugated estradiol, total/unconjugated 2-methoxyestrone, 4-methoxyestrone and unconjugated estriol). The relative concentrations of 2- and 4-pathway EM did not differ between the MHT users (2-pathway EM comprised 15% and 4-pathway EM <2% of the total), but 16-pathway EM were lower in E alone users (p = 0.036). Ratios of 2- and 4-pathway EM compared to 16-pathway EM were significantly higher in E alone compared to E + P users. Similar but not significant patterns were observed in CEE-alone and CEE + MPA users. Our data suggest that compared to E + P users, women using E alone have more extensive metabolism via the 2- vs. the competing 16-pathway. This is consistent with epidemiologic evidence of reduced postmenopausal breast cancer risk associated with this metabolic profile and may provide a clue to the breast cancer risk reduction in CEE alone users during the WHI.  相似文献   
9.
目的:探讨二仙汤对围绝经期大鼠心脏电生理的作用及机制。方法:雌性SD大鼠,根据体质量随机分组,分为假手术组,模型组,戊酸雌二醇组(8×10~(-4)g·kg~(-1)·d~(-1)),二仙汤低、中、高剂量组(4,8,12 g·kg·~(-1)d~(-1))。除假手术组外,其余各组大鼠均彻底摘除卵巢复制围绝经期大鼠模型。同时分别灌胃给药,假手术组和模型组则灌胃等量生理盐水,每天1次,连续80 d。以生物信号采集仪连接Ⅱ导联电极记录大鼠心电图,酶联免疫吸附测定(ELISA)检测大鼠血清中雌二醇(E2)的含量,苏木素-伊红(HE)染色观察大鼠子宫病理形态学变化,蛋白免疫印迹法(Western bot)检测大鼠心肌组织中雌激素α受体(ERα)蛋白的表达。结果:与假手术组比较,模型组大鼠心电图P波,R波,T波幅度显著减小(P 0. 01),PR间期,QRS时程,QT间期不同程度的缩短,大鼠血清中E2水平显著降低(P 0. 01);大鼠子宫明显干瘪,皱缩,子宫内膜层变薄,腺体数量明显减少;心肌组织ERα受体蛋白表达显著降低(P 0. 01)。与模型组比较,二仙汤各剂量组均能改善上述大鼠子宫的病理变化,中、高剂量二仙汤能显著升高E2水平(P 0. 01),显著逆转上述子宫的病理变化,上调ERα受体蛋白的表达(P 0. 01)。结论:二仙汤能改善围绝经期大鼠的心脏电生理变化,其机制可能与提高大鼠体内雌激素活性和雌激素受体表达有关。  相似文献   
10.
目的:探讨他莫昔芬(TAM)对雌激素受体(ER)阴性、G蛋白偶联雌激素受体(GPER)阳性乳腺癌细胞上皮间质转化(EMT)的影响。方法:以ER阴性(ER-)、GPER阳性(GPER+)乳腺癌MDA-MB-468细胞为研究对象,用TAM处理细胞,GPER特异性抑制剂G15抑制胞内GPER活性,siRNA干扰GPER蛋白表达,侵袭小室实验检测细胞侵袭能力,Western blot检测ERα、GPER、Vimentin、E-cadherin及N-cadherin蛋白表达变化。结果:TAM(5 μmol/L)可明显增强MDA-MB-468细胞的侵袭能力(P<0.01);G15(10 μmol/L)预处理能显著抑制TAM诱导的细胞侵袭活动(P<0.01);GPER-siRNA可明显干扰MDA-MB-468细胞GPER蛋白表达(P<0.01);干扰GPER蛋白表达能有效抑制TAM诱导的细胞侵袭活动(P<0.01)。TAM处理明显诱导Vimentin和N-cadherin蛋白表达上调(P<0.01),E-cadherin蛋白表达下调(P<0.01);G15预处理或干扰GPER蛋白表达均能抑制TAM的上述诱导作用(均P<0.05)。结论:TAM能诱导ER- GPER+乳腺癌MDA-MB-468细胞EMT,其作用与其激活GPER有关。  相似文献   
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