Effects of Estrogen-related Receptor alpha (ERRα) on Proliferation and Metastasis of Human Lung Cancer A549 Cells

Estrogen-related receptor alpha （ERRα） plays an important role in the development of hor- monezdependent cancers, but its roles in lung cancer remain elusive. The present study was aimed to investigate the effects of ERRα on the proliferation and metastasis of lung cancer A549 cells. The mRNA and protein levels of ERRor were detected in lung cancer A549 and MCF-7 cells and bronchial epithelial BEAS-2B cells by qRT-PCR and Western blotting, respectively. ERRor plasmid transfection and XCT-790 （an inverse agonist of ERRc0 were used to up-regulate or down-regulate ERRα expression in A549 cells, respectively. The viability of A549 cells was measured by cell counting kit-8 （CCK-8） and the motility of A549 cells by wound healing assay and Transwell migration/invasion assay. The epithelial markers E-cadherin （E-Cad） and zona occludin-1 （ZO-1）, the mesenchymal markers fi- bronectin （FN） and vimentin （Vim） and the transcription factors （Snail, Zebl Twist and Slug） were fur- ther detected at mRNA and protein levels by qRT-PCR and Western blotting, respectively. The results showed that ERRor promoted the growth of lung cancer A549 cells in vitro. XCT-790 significantly in- hibited the migration and invasion of A549 cells. Over-expression of ERRα promoted the epithe- lial-to-mesenchymal transition （EMT） of A549 ceils, down-regulated the epithelial makers E-Cad and ZO-1, and up-regulated the mesenchymal makers FN and Vim. Silencing of Slug, but not other tran- scription factors, significantly abolished the ERRs-induced EMT of A549 cells. It was suggested that ERRor promoted the migration and invasion of A549 cells by inducing EMT, and Slug was involved in the process. Targeting ERRor might be an efficient approach for lung cancer treatment.

T29C genotype polymorphism of estrogen receptor alpha is associated with initial response to interferon-alpha therapy in chronic hepatitis B patients

BACKGROUND: Virological clearance, delayed progression to cirrhosis or liver cancer, and increased survival are the long-term goals of antiviral therapy in chronic hepatitis B patients. Identification of host factors correlated with therapeutic response may contribute greatly to individual treatment. This study aimed at investigating whether T29C genotype polymorphism of estrogen receptor alpha (ESR1) is associated with the initial response to interferon-alpha (IFN-alpha) therapy in chronic hepatitis B patients. METHODS: The initial responses of 100 patients to IFN-alpha therapy were evaluated and compared by classifying them into three groups according to T29C genotype polymorphism of ESR1: T/T, TIC, and C/C genotype groups. Polymerase chain reaction-restriction fragment length polymorphism was used to analyze the genotype polymorphism in T29C. RESULTS: The frequency of initially combined response was markedly higher in both the T/T and TIC groups than in the C/C group (Z=10.326, P=0.006 and Z=26.247, P=0.000, respectively). In addition, the initial virological response was higher in the T/T and T/C groups than the C/C group (chi(2)=5.674, P=0.017 and chi(2)=4.980, P=0.026, respectively). In 78 initially HBeAg-positive patients, however, the frequency of initial e-antigen disappearance or seroconversion among the T/T, T/C, and C/C genotype groups was 34.15%, 27.78% and 15.79%, respectively, which were not significantly different. CONCLUSION. The T29C genotype polymorphism of ESR1 is associated with the initial response to IFN-alpha in patients with chronic hepatitis B, and might be a significant marker for predicting the initial response to IFN-alpha, at least in this study population. (Hepatobiliary Pancreat Dis Int 2010; 9: 275-279)

Expression of estrogen receptor alpha,nerve growth factor,interleukin-2,and androgen receptor in the cerebellum of ovariectomized rats following soybean isoflavone treatment

BACKGROUND： Studies have shown that estrogen receptor alpha （ERα）, nerve growth factor （NGF）, interleukin-2 （IL-2）, and androgen receptor （AR） expression in the cerebellum decreases when estrogen levels decrease in vivo. Soybean isoflavone, a type of non-steroid estrogen with similar molecular structure and function to estradiol, exhibits estrogen-like characteristics. OBJECTIVE： To investigate the effects of various doses of soybean isoflavone on expression of ERa, NGF, IL-2, and AR in the cerebellum of ovariectomized rat, and to determine whether there is a dose-dependent effect.DESIGN, TIME AND SETTING： Controlled trial at the cellular and molecular level. The study was performed at the Experimental Animal Engineering Center, College of Veterinary Medicine, Sichuan Agricultural University from July 2006 to May 2008. MATERIALS： Soybean isoflavone, comprised of daidzin, genistein and isoflavone, was provided by Taiyuan Yuantai Biochemical Industry, China. The ERα, NGF, IL-2, and AR in situ hybridization kit, rabbit anti-rat ERa, NGF, IL-2, and AR monoclonal antibodies, and SABC kit were purchased from Wuhan Boster Biological Technology, China. METHODS： A total of 50 female, Sprague Dawley rats, aged 3 months, were randomly assigned to 5 groups, with 10 animals in each group. With the exception of the sham-operation group （abdominal cavity opening alone）, all rats underwent bilateral ovariectomy. At 14 days after surgery, rats in the high-, middle-, and low-dose soybean isoflavone groups were subcutaneously injected with 1.5, 1.0, and 0.5 mg/kg soybean isoflavone, respectively, every 2 days for 6 consecutive weeks. Rats in the sham-operation and ovariectomized groups were subcutaneously injected with absolute alcohol （0.5 mL/kg）. MAIN OUTCOME MEASURES： Expression levels and distribution of ERα, NGF, IL-2, and AR in the cerebellum were detected by immunohistochemistry and in situ hybridization. RESULTS： Compared with the sham-operation group, immunoreactive products and hybridization signals of ERa, NGF, IL-2, and AR were significantly decreased in the cerebellar cortex and nuclei of ovariectomized rats （P 〈 0.05 or P 〈 0.01）, but increased following soybean isoflavone treatment. In particular, levels of the high-dose soybean isoflavone group were almost restored to levels of the sham-operation group （P 〉 0.05）. The immunoreactive products were primarily located in the cytoplasm and neurites, and rarely in the cell membrane and nuclei. However, the hybridization signals were predominantly located in the nuclei, but rarely in the cytoplasm, cell membrane, or neurites. CONCLUSION： Soybean isoflavone upregulated ERα, NGF, IL-2, and AR protein and gene expression in a dose-dependent manner, and played an important role in sustaining and protecting structure and function of cerebellar neurons. Moreover, the similarity of expression patterns of these molecules indicated that they were mutually interactive during the regulation of soybean isoflavone to the cerebellum.

Estrogen Receptor Alpha 36 Gene Knockdown Promote the Expression of NF-κB in PC12 Cells

The nuclear transcription factors κB (NF-κB) is widely existing in various kinds of cell types in the nervous system and plays an important role in neuron apoptosis and neurodegenerative diseases. Estrogen receptor alpha 36 (ER-α36), is a novel variant of ERα (as known ER-α66) which can transduce both estrogenand antiestrogen-dependent activation of MAPK signal pathway and stimulate cell growth. Here, we aimed to detect the effect of ER-α36 gene silencing on the expression of NF-κB in normal cultured PC12 cells and to provide an experimental foundation for understanding the function of ER-α36 innerve cells. PC12 cells with ER-α36 expression knocked down by the shRNA method. Then Western blot and immunocytochemical staining were performed to detect the expression and translocation of NF-κB after transfection. The results showed that NF-κB expression was significantly higher comparing with the control group after transfection (P 0.01). Also, NF-κB subunit entered nuclear after transfection;Immunofluorescence staining and immunocytochemical staining of PC12 cells demonstrated that ER-α36 was expressed mainly on the plasma membrane and on the cell nucleus membrane. These data indicate that ER-α36 gene silencing can increase the expression of NF-κB and promote its nuclear translocation in PC12 cells.

Polyubiquitination inhibition of estrogen receptor alpha and its implications in breast cancer

Estrogen receptor alpha(ERα) is detected in more than 70% of the cases of breast cancer. Nuclear activity of ERα, a transcriptional regulator, is linked to the development of mammary tumors, whereas the extranuclear activity of ERα is related to endocrine therapy resistance. ERα polyubiquitination is induced by the estradiol hormone, and also by selective estrogen receptor degraders, resulting in ERα degradation via the ubiquitin proteasome system. Moreover, polyubiquitination is related to the ERα transcription cycle, and some E3-ubiquitin ligases also function as coactivators for ERα. Several studies have demonstrated that ERα polyubiquitination is inhibited by multiple mechanisms that include posttranslational modifica-tions, intera-ctions with coregula-tors, a-nd forma-tion of specific protein complexes with ERα. These events are responsible for an increase in ERα protein levels and deregulation of its signaling in breast cancers. Thus, ERα polyubiquitination inhibition may be a key factor in the progression of breast cancer and resistance to endocrine therapy.

Estrogen receptor alpha gene amplification in breast cancer:25 years of debate

Twenty-five years ago,Nembrot and colleagues reported amplification of the estrogen receptor alpha gene(ESR1) in breast cancer,initiating a broad and still ongoing scientific debate on the prevalence and clinical significance of this genetic aberration,which affects one of the most important genes in breast cancer.Since then,a multitude of studies on this topic has been published,covering a wide range of divergent results and arguments.The reported prevalence of this alteration in breast cancer ranges from 0% to 75%,suggesting that ESR1 copy number analysis is hampered by technical and interpreter issues.To date,two major issues related to ESR1 amplification remain to be conclusively addressed:(1) The extent to which abundant amounts of messenger RNA can mimic amplification in standard fluorescence in situ hybridization assays in the analysis of strongly expressed genes like ESR1,and(2) the clinical relevance of ESR1 amplification:Such relevance is strongly disputed,with data showing predictive value for response as well as for resistance of the cancer to anti-estrogen therapies,or for subsequent development of cancers in the case of precursor lesions that display amplification of ESR1.This review provides a comprehensive summary of the various views on ESR1 amplification,and highlights explanations for the contradictions and conflicting data that could inform future ESR1 research.

Estrogen affects neuropathic pain through upregulating N-methyl-D-aspartate acid receptor 1 expression in the dorsal root ganglion of rats

Estrogen affects the generation and transmission of neuropathic pain,but the specific regulatory mechanism is still unclear.Activation of the N-methyl-D-aspartate acid receptor 1（NMDAR1） plays an important role in the production and maintenance of hyperalgesia and allodynia.The present study was conducted to determine whether a relationship exists between estrogen and NMDAR1 in peripheral nerve pain.A chronic sciatic nerve constriction injury model of chronic neuropathic pain was established in rats.These rats were then subcutaneously injected with 17β-estradiol,the NMDAR1 antagonist D（-）-2-amino-5-phosphonopentanoic acid（AP-5）,or both once daily for 15 days.Compared with injured drug na？ve rats,rats with chronic sciatic nerve injury that were administered estradiol showed a lower paw withdrawal mechanical threshold and a shorter paw withdrawal thermal latency,indicating increased sensitivity to mechanical and thermal pain.Estrogen administration was also associated with increased expression of NMDAR1 immunoreactivity（as assessed by immunohistochemistry） and protein（as determined by western blot assay） in spinal dorsal root ganglia.This 17β-estradiol-induced increase in NMDAR1 expression was blocked by co-administration with AP-5,whereas AP-5 alone did not affect NMDAR1 expression.These results suggest that 17β-estradiol administration significantly reduced mechanical and thermal pain thresholds in rats with chronic constriction of the sciatic nerve,and that the mechanism for this increased sensitivity may be related to the upregulation of NMDAR1 expression in dorsal root ganglia.

Expression of estrogen receptor (ER) -α and -βtranscripts in the neonatal and adult rat cerebral cortex, cerebellum, and olfactory bulb

In the present study expression of estrogen receptor subtype -alpha (ERalpha) and -beta (ERbeta) in the cerebral cortex, cerebellum, and olfactory bulb was investigated and compared between neonatal (1 to approximately 3-days-old) and adult (250 to approximately 350 g) rats, using reverse transcription-polymerase chain reaction (RT-PCR). No ERalpha transcripts were detectable in the adult cerebellum and olfactory bulb, whereas very weak expression of ERalpha was present in the adult cerebral cortex. No significant difference in ERbeta transcripts was detectable between the neonatal and adult rats. While transcripts for both ER subtypes were co-expressed in these brain areas of neonatal rats, although ERalpha expression was significantly weaker than ERbeta. Even in the cerebral cortex known to contain both ER subtypes in adult rats, ERalpha transcripts in neonatal rats were much higher than in adult. These observations provide evidence for the existence of different expression patterns of ERalpha/ERbeta transcripts in these three brain areas between the neonatal and adult rats, suggesting that each ER subtype may play a distinct role in the regulation of differentiation, development, and functions of the brain by estrogen.

Expression of estrogen receptor alpha in preimplantation mice embryos

Objective:To study the expression of estrogen receptor alpha(ERα) in preimplantation mice embryos.Methods:Mice zygotes were collected from superovulated Kunming mice and cultured in vitro.Embryos at different developmental stages were collected at 0,24,36,48,72 and 96hours after cultivation.The expression of ERα in early mice embryos was detected by reverse transcription-PCR(RT-PCR) and immunocytochemistry.Results:The expression of ERα mRNA was detected in all of the examined embryonic stages.The relative amount of ERα mRNA showed no significant difference between 1-cell stage embryos and 4-cell stage embryos(P>0.05).However,the relative level of ERα mRNA significantly decreased(P<0.05) at 2-cell stage and was the lowest at this stage.Over 2-cell stage,the ERα mRNA relative level would increase and achieve the peak level at blastocyst stage.The location of immunocytochemistry showed that ERα immunopositive cells could be firstly detected at 8-cell stage,after which they are consistently detected until blastocyst stage.In addition,the intensity of ERα positive staining was higher at blastocyst stage compared with that at 8-cell stage and morula stage.Conclusion:ERα is expressed in preimplantation mice embryos in a temporal and spatial pattern and may be involved in regulating the development of early mice embryos,which probably plays crucial roles in early embryonic development.

Increased Cellular Invasion and Proliferation via Estrogen Receptor after 17-<i>β</i>-Estradiol Treatment in Breast Cancer Cells Using Stable Isotopic Labeling with Amino Acids in Cell Culture (SILAC)

17-β-estradiol (estrogen) is a steroid hormone important to human development;however, high levels of this molecule are associated with increased risk of breast cancer primarily due to estrogen’s ability to bind and activate the estrogen receptor (ER) and initiate gene transcription. Currently, estrogen mechanisms of action are classified as genomic and non-genomic and occur in an ER-dependent and ER-independent manner. In this study, we examine estrogen signaling pathways, by measuring changes in protein expression as a function of time of exposure to estrogen in both ER-positive (MCF-7) and ER-negative (MDA-MB-231) cell lines. Using a robust experimental design utilizing isotopic labeling, two-dimensional LC-MS, and bioinformatics analysis, we report genomic and non-genomic ER regulated estrogen responsive proteins. We find a little over 200 proteins differentially expressed after estrogen treatment. Cell proliferation, transcription, actin filament capping and cell to cell signaling are significantly enriched in the MCF-7 cell line alone. Translational elongation and proteolysis are enriched in both cell lines. Subsets of the proteins presented in this study are for the first time directly associated with estrogen signaling in mammary carcinoma cells. We find that estrogen affected the expression of proteins involved in numerous processes that are related to tumorigenesis such as increased cellular division and invasion in an ER-dependent manner. Moreover, we identified negative regulation of apoptosis as a non-genomic process of estrogen. This study complements gene expression studies and highlights the need for both genomic and proteomic analyses in unraveling the complex mechanisms by which estrogen affects progression of breast cancer.

乳腺癌组织中COL11A1表达与ER、PR、HER-2和Ki-67的相关性分析

目的探讨乳腺癌组织中Ⅺ型胶原α1(COL11A1)表达与雌激素受体(ER)、孕激素受体(PR)、人表皮生长因子受体-2(HER-2)和Ki-67的关系。方法采用免疫组化EnVision两步法检测18例乳腺纤维腺瘤组织和120例乳腺癌组织(36例原位癌组织、84例浸润性癌组织)中COL11A1的表达,同时对乳腺癌组织进行ER、PR、HER-2和Ki-67免疫组化检测,对HER-2(2+)进行荧光原位杂交检测;分析COL11A1表达与乳腺癌临床病理特征和多种免疫标记(ER、PR、HER-2和Ki-67)的关系。结果免疫组化结果显示COL11A1主要表达于乳腺癌细胞中。在纤维腺瘤组织中COL11A1表达呈弱阳性。COL11A1在原位癌中表达高于浸润性乳腺癌(P<0.05)。COL11A1表达与乳腺癌患者的年龄、部位、肿块大小和淋巴结转移无关(P>0.05),而中、高分化组织的COL11A1表达水平高于低分化组织,差异有统计学意义(P<0.05)。进一步分析COL11A1与乳腺癌其他免疫标记间的相关性发现,在Ki-67高表达组织中COL11A1低表达的比例更高,差异有统计学意义(P<0.05),而其他3种标记与COL11A1的表达无关(P>0.05)。结论COL11A1在浸润性乳腺癌中表达较原位癌低,在低分化乳腺癌中表达水平较中高分化更低,且与Ki-67表达有关,提示COL11Al表达在乳腺癌发生发展过程中是动态变化的,为乳腺癌的诊断治疗提供潜在标记物。

雌激素相关受体alpha特性抑制剂XCT-790对细胞糖代谢的影响

目的探讨雌激素相关受体α(ERRα)特异性抑制剂XCT-790对细胞糖代谢的影响。方法采用同位素示踪技术检测XCT-790对细胞糖酵解和糖吸收的影响,实时定量PCR检测XCT-790对糖代谢相关基因表达的影响。结果 ERRα特异性抑制剂XCT-790可以显著地增加细胞的糖酵解和糖吸收,并降低ERRa靶基因SDH和Nduf表达,增加糖代谢相关基因Tigar的表达。结论 ERRα特异性抑制剂XCT-790可以显著地增加癌细胞糖酵解和糖代谢。

Estrogen-related receptor γ disruption of source water and drinking water treatment processes extracts

Environmental chemicals in drinking water can impact human health through nuclear receptors. Additionally, estrogen-related receptors （ERRs） are vulnerable to endocrine-disrupting effects. To date, however, ERR disruption of drinking water potency has not been reported. We used ERRy two-hybrid yeast assay to screen ERRy disrupting activities in a drinking water treatment plant （DWTP） located in north China and in source water from a reservoir, focusing on agonistic, antagonistic, and inverse agonistie activity to 4-hydroxytamoxifen （4-OHT）. Water treatment processes in the DWTP consisted of pre-chlorination, coagulation, coal and sand filtration, activated carbon filtration, and secondary chlorination processes. Samples were extracted by solid phase extraction. Results showed that ERRγ antagonistic activities were found in all sample extracts, but agonistic and inverse agonistic activity to 4-OHT was not found. When calibrated with the toxic equivalent of 4-OHT, antagonistic effluent effects ranged from 3.4 to 33.1 μg/L. In the treatment processes, secondary chlorination was effective in removing ERRy antagonists, but the coagulation process led to significantly increased ERRy antagonistic activity. The drinking water treatment processes removed 73.5 % of ERRy antagonists. To our knowledge, the occurrence of ERRy disruption activities on source and drinking water in vitro had not been reported previously. It is vital, therefore, to increase our understanding of ERRγ disrupting activities in drinking water.

Effects of delayed estrogen treatment and 20-HETE synthesis inhibition on postischemic pial artery response to acetylcholine in rats

Relatively little is known about the effects of estrogen on postischemic cerebral vasomotor dynamics after ischemic injury. Emerging hypotheses suggest that the timing after menopause at which hormone replacement is initiated might be important and might modulate the potential benefits of estrogen on brain rescue once a cerebral ischemic event occurs. Therefore, we sought to determine if protracted hypoestrogenicity modifies estrogen’s protective effects on postischemic pial artery dilatory dysfunction and if the arachidonic acid metabolite 20-hydroxyeicosatetraeonic (20-HETE) contributes to the dysfunction. Pial artery dilation to acetylcholine was examined before and 1 hour after 15 minutes forebrain ischemia. The rat study groups included: sexually mature males (M), naive (N), OVX (OV), estrogen-treated OVX females (E1;estrogen started 1 week post ovariectomy) and delayed estrogen-treated (E10;started 10 weeks post ovariectomy) females. Postischemic responses were assessed before and after superfusion of the 20-HETE synthesis inhibitor N-hydroxy-N’-(4-butyl-2-methylphenyl)-formamidine (HET0016). Postischemic acetylcholine dilation was depressed in M, OV and E10 compared to N and E1 rats. Compared to E1, delayed estrogen replacement worsened acetylcholine-induced dilation. Postischemic microvascular estrogen receptor alpha (ERα) density was similar in the OV, E1 and E10 rats. Postischemic application of HET0016 failed to improve acetylcholine dilation. Continuous infusion of HET0016 during and after ischemia did not reverse postischemic pial vasodilatory dysfunction. Timing of estrogen replacement may be critical for vascular health after cerebral ischemic injury. Postischemic loss of acetylcholine reactivity does not appear to involve mechanisms related to 20-HETE synthesis or microvascular ERα expression.

直肠癌患者MDSC百分比和RORαmRNA、IL-17E mRNA、FOXP3 mRNA表达的临床意义

目的探讨外周血单个核细胞(PBMC)中视黄酸相关孤儿核受体α(RORα)mRNA、白细胞介素17E(IL-17E)mRNA、叉头框蛋白P3(FOXP3)mRNA和髓源性抑制细胞(MDSC)百分比在直肠癌中的临床价值。方法选取直肠癌患者95例(直肠癌组)、健康体检者45名(正常对照组),收集所有研究对象的临床资料,检测所有研究对象PBMC中RORαmRNA、FOXP3 mRNA、IL-17E mRNA水平和MDSC百分比。结果直肠癌组FOXP3 mRNA、IL-17E mRNA相对表达量和MDSC百分比均高于正常对照组(P<0.05),RORαmRNA相对表达量低于正常对照组(P<0.05)。有淋巴转移、TNM分期Ⅲ期的直肠癌患者FOXP3mRNA、IL-17E mRNA相对表达量和MDSC百分比分别高于无淋巴转移、TNM分期Ⅰ~Ⅱ期的患者(P<0.05),RORαmRNA相对表达量分别低于无淋巴转移、TNM分期Ⅰ~Ⅱ期的患者(P<0.05)。不同性别、年龄、肿瘤直径的直肠癌患者之间RORαmRNA、FOXP3 mRNA、IL-17E mRNA相对表达量和MDSC百分比差异均无统计学意义(P>0.05)。结论直肠癌患者IL-17E mRNA、FOXP3 mRNA水平和MDSC显著升高,RORαmRNA水平显著降低,且与TNM分期和淋巴转移有关,或可作为直肠癌筛查和病情监测的指标。

柴胡四物汤对围绝经期综合征模型大鼠血清E_(2)水平、子宫形态及ERα表达的影响

目的:通过观察柴胡四物汤对围绝经期综合征模型大鼠血清E_(2)水平、子宫形态及子宫、下丘脑ERα表达的影响,初步探讨柴胡四物汤治疗围绝经期综合征的作用机制。方法:将75只雌性SD大鼠随机分为假手术组、模型组、西药组、柴胡四物汤高、中、低剂量组,采用双侧卵巢切除法造模,选取符合条件的60只大鼠纳入实验,每组10只。从术后第14天开始,连续给药28 d。给药结束后,观察各组大鼠子宫指数及形态学的改变;采用ELISA法检测血清E_(2)水平;采用RT-PCR法及Western Blot法检测子宫、下丘脑ERα的表达水平。结果:与假手术组比较,模型组血清E_(2)水平明显下降(P<0.01),子宫湿重、子宫指数显著下降(P<0.01),子宫体积明显缩小,宫腔变窄,腺体数量较少,内膜及肌层萎缩,子宫ERαmRNA及蛋白的表达水平明显下降(P<0.01),下丘脑ERαmRNA及蛋白的表达水平显著升高(P<0.01)。与模型组比较,西药组、柴胡四物汤高、中剂量组血清E_(2)水平明显升高(P<0.01),西药组、柴胡四物汤高、中、低剂量组的子宫指数明显上升(P<0.01),子宫腺体数量增加,内膜及肌层的萎缩程度有所缓解,西药组、柴胡四物汤高、中剂量组子宫ERαmRNA表达水平增加(P<0.01),西药组、柴胡四物汤高剂量组子宫ERα蛋白表达水平增加(P<0.01),西药组、柴胡四物汤高、中、低剂量组下丘脑ERαmRNA及蛋白的表达水平降低(P<0.01)。结论:柴胡四物汤可改善围绝经期的各类症状,其作用机制可能与升高围绝经期综合征模型大鼠血清E_(2)水平,改善子宫指数及萎缩程度,提高子宫ERα的表达并同时下调下丘脑ERα的表达有关。

Association of estrogen receptor alpha gene polymorphisms with bone mineral density： a meta-analysis

Background A number of studies have examined the association between estrogen receptor alpha （ESR-a） gene polymorphisms and bone mineral density （BMD）, but previous studies of ESR-a gene Xbal （rs9340799） and Pvull （rs2234693） polymorphisms have been hampered by small sample size, regional restrictions and inconclusive results. Thus a meta-analysis is needed to assess their pooled effects. Methods This study reviewed all published articles indexed in Pubmed using the keywords in the title or abstract. All data were extracted independently by two reviewers using a standard form, the studies were meta-analyzed and minor discrepancies were resolved by authors＇ discussion. Results Twenty seven eligible studies involving 8467 women and 2032 men were identified. The Xbal and Pvull polymorphisms were significantly associated with BMD of the lumbar spine. XX and PP homozygotes had a protective effect in comparison with carriers of the x and p alleles, the effects were more significant in premenopausal women or Western women. At the femoral neck, the results were different. XX served as a protective factor in postmenopausal women, Western women, Western postmenopausal women, and men, while PP was likely to serve as a risk factor in Eastern women, Eastern postmenopausal women, and men. Conclusions The Xbal polymorphism is correlated to BMD at diverse skeletal sites. PP had a protective role for the lumbar spine but might be a risk factor for the femoral neck.

Stable transfection of estrogen receptor-alpha suppresses expression of cyclooxygenase-2 and vascular endothelial growth factor-C in MDA-MB-231 breast cancer cells

Background Estrogen receptor （ER）-negative breast cancer cells are more aggressive than ER-positive cells. Elevated levels of cyclooxygenase-2 （COX-2） and vascular endothelial growth factor-C （VEGF-C） expression have been detected in cultured human breast cancer cells and are associated with negative hormone receptor status. In this study, we created ERα stable transfectants in MDA-MB-231 cells to explore the effect of ERα on cell growth and COX-2 and VEGF-C expression.Methods The green fluorescent protein （GFP）-ERα plasmids were stably transfected into ER-negative MDA-MB-231 cells. The proliferation and migration of untransfected MDA-MB-231 cells, ERα-transfected MDA-MB-231 cells and ER-positive MCF-7 cells were determined. The expression of COX-2, and the levels of VEGF-C mRNA and the VEGF-C secretion concentration were assayed in these cell lines.Results The proliferation and migration capacities of ERα-tranfected MDA-MB-231 cells were significantly decreased （P 〈0.05）. The expression of COX-2 was significantly lower in ERa-tranfected MDA-MB-231 cells than in untranfected MDA-MB-231 cells. The mRNA and protein levels of VEGF-C were lower in ERa-tranfected MDA-MB-231 cells than in untransfected MDA-MB-231 cells （P〈0.05）.Conclusions ERα stable transfection inhibits proliferation and migration capacities of MDA-MB-231 cells and decreases expression of COX-2 and VEGF-C. The decreases of proliferation and migration capacities may be related to suppression of COX-2 and VEGF-C expression.

雌激素受体α在绝经后骨质疏松中的研究进展及作用机制

绝经后骨质疏松(postmenopausal osteoporosis, PMOP)是亟需解决的公共健康问题。患者雌激素减少,雌激素受体(estrogen receptor α,ERα)表达水平下降,成骨细胞功能下降,破骨细胞活性增强,骨代谢偶联失衡。ERα在PMOP的发生发展中具有重要作用,笔者从PubMed、Web of Science和中国知网检索近10年(2013-2023年)骨质疏松研究领域的文献,总结归纳ERα在骨髓间充质干细胞、成骨细胞祖细胞、成骨细胞前体细胞、成熟成骨细胞、破骨细胞和骨细胞中的作用,并以能显著改善PMOP的黄酮类成分淫羊藿苷为例阐述基于ERα的抗PMOP相关机制。

17β-雌二醇调控子宫内膜癌细胞孤儿核受体ERRα表达的研究

背景与目的:雌激素受体相关受体α(estrogenreceptor-relatedreceptorα,ERRα)是孤儿核受体亚家族成员之一,可与雌激素受体α(estrogenreceptorα,ERα)竞争结合同一靶基因位点,从而干扰雌激素-雌激素受体核内信号通路的转导,因而可能在子宫内膜癌的发生方面发挥一定作用。本研究旨在探讨17β-雌二醇(E2)对子宫内膜癌细胞孤儿核受体ERRα的调控作用,明确ERRα在子宫内膜癌发生中的作用及与ER信号通路的关系。方法:采用RT-PCR和Westernblot方法,检测不同浓度17β-E(210-10、10-8、10-6mol/L)作用于ERα阳性的子宫内膜癌细胞系Ishikawa细胞和ERα阴性的子宫内膜癌细胞系HEC-IA细胞24h、48h后ERRαmRNA水平和蛋白水平的变化,并应用完全性ER拮抗剂ICI182780同时作用细胞,观察是否可阻断E2对ERRα的调控作用。结果:不同浓度的17β-E2作用于Ishikawa细胞24h、48h后ERRαmRNA水平及蛋白水平均有不同程度的下调,以10-8mol/L作用后下调最明显。同时加入10-8mol/LE2和10-6mol/LICI182780作用于Ishikawa细胞后,E2对ERRα的下调作用被阻断。不同浓度的17β-E2作用于HEC-IA细胞24h后ERRαmRNA水平出现不同程度上调,但蛋白水平未见明显变化。当17β-E2作用细胞48h后,ERRα蛋白水平出现明显上调,以10-8mol/L作用后上调最明显。同时加入10-8mol/LE2和10-6mol/LICI182780作用于HEC-IA细胞后,E2对ERRα的上调作用无明显变化。结论:17β-E2可下调Ishikawa细胞ERRα的表达,且这种降调作用是通过ER介导完成的;17β-E2可上调HEC-IA细胞ERRα的表达,且这种上调作用不被完全性ER拮抗剂ICI182780所阻断。