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1.
《Allergology international》2022,71(4):432-436
Steroid hormones, especially glucocorticoids, androgens, and estrogens, have profound influence on immunity. Recent studies using cell-type specific steroid hormone receptor-deficient mice have revealed the precise roles of some of these hormones in the immune system. Glucocorticoids are known to have strong anti-inflammatory and immunosuppressive effects and pleiotropic effects on innate and adaptive immune responses. They suppress the production of inflammatory cytokines by macrophages and DCs and the production of IFN-γ by NK cells, thus inhibiting innate immunity. By contrast, glucocorticoids enhance the immune response by inducing the expression of IL-7R and CXCR4 in T cells and the accumulation of T cells in lymphoid organs in accordance with the diurnal change of the glucocorticoid concentration. Thus, glucocorticoids suppress innate immunity but enhance adaptive immunity. Androgens suppress the homeostasis and activation of ILC2s and the differentiation of Th2 and Th17 cells and enhance the suppressive function of Tregs, thereby alleviating allergic airway inflammation. Thus, these steroid hormones have pleiotropic functions in the immune system. Further investigations are awaited on the regulation of immunity and allergy by estrogens using cell-specific steroid hormone receptor-deficient mice. 相似文献
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目的探讨新型雌激素受体亚型ER-α30和ER-α36在乳腺癌中的表达及与他莫昔芬治疗预后的关系。方法收集2015年1月至2015年11月间在河北北方学院附属第一医院接受他莫昔芬内分泌治疗的Luminal A型乳腺癌患者75例,并收集同时期30例ER(-)乳腺癌患者组织。采用免疫组化染色SP法检测ER-α30和ER-α36蛋白表达。分析ER-α30和ER-α36蛋白表达与Luminal A型乳腺癌临床病理特征的关系。随访患者的无病生存时间(DFS)。采用Cox风险比例回归模型分析影响DFS的因素。结果Luminal A型乳腺癌组织中ER-α30蛋白阳性表达率为32.0%(24/75),低于ER(-)乳腺癌组织(P<0.05)。ER-α30蛋白表达与TNM分期、肿瘤直径、浸润深度、淋巴结转移、孕激素受体状态有关(P<0.05)。ER-α36蛋白阳性表达率为52.0%(39/75),与ER(-)乳腺癌组织比较差异无统计学意义(P>0.05)。ER-α36蛋白表达与TNM分期和肿瘤直径有关(P<0.05)。随访时间为11~54个月,患者48个月无病生存率为64.0%(48/75)。ER-α30阳性患者48个月无病生存率为33.33%(8/24),阴性患者为78.43%(40/51),差异具有统计学意义(P=0.001)。ER-α36阳性患者48个月无病生存率为48.7%(19/39),阴性患者为80.6%(29/36),差异具有统计学意义(P=0.002)。Cox风险比例回归分析显示,ER-α30、ER-α36是影响Luminal A型乳腺癌患者DFS的独立预后因素(P<0.05)。结论Luminal A型乳腺癌ER-α30和ER-α36阳性表达者接受他莫昔芬治疗无病生存期较短,其有望成为预测他莫昔芬治疗反应性的重要指标。 相似文献
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《Journal of thoracic oncology》2020,15(1):62-79
IntroductionMounting evidence supports a role for estrogen signaling in NSCLC progression. We previously reported a seven-gene signature that predicts prognosis in estrogen receptor β positive (ERβ+) NSCLC. The signature defines a network comprised of ER and human EGFR-2/3 (HER2/HER3) signaling.MethodsWe tested the efficacy of combining the pan-HER inhibitor, dacomitinib, with the estrogen antagonist, fulvestrant, in ERβ+ NSCLC models with differing genotypes. We assessed the potency of this combination on xenograft growth and survival of host mice, and the ability to reverse the gene signature associated with poor outcome.ResultsSynergy was observed between dacomitinib and fulvestrant in three human ERβ+ NSCLC models: 201T (wild-type EGFR), A549 (KRAS mutant), and HCC827 (EGFR 19 deletion) with combination indices of 0.1-0.6. The combination, but not single agents, completely reversed the gene signature associated with poor prognosis in a mechanism that is largely mediated by activator protein 1 downregulation. In vivo, the combination also induced tumor regression and reversed the gene signature. In HCC827 xenografts treated with the combination, survival of mice was prolonged after therapy discontinuation, tumors that recurred were less aggressive, and two mechanisms of HER inhibitor resistance involving c-Met activation and PTEN loss were blocked.ConclusionsThe combination of an ER blocker and a pan-HER inhibitor provides synergistic efficacy in different models of ERβ+ NSCLC. Our data support the use of this combination clinically, considering its ability to induce potent antitumor effects and produce a gene signature that predicts better clinical outcomes. 相似文献
4.
【摘要】目的 探讨鲜天南星水提取物对小鼠子宫纤维瘤的抑制作用及对小鼠雌激素水平的影响。方法 选取SD健康雌性小鼠30只,随机分为正常组、模型组、实验组3组,每组各10只,对模型组、实验组进行子宫纤维瘤模型建立,正常组不作处理。实验组小鼠予以鲜天南星水提取物进行干预,正常组、模型组小鼠注射等体积生理盐水。对小鼠子宫重及子宫系数进行统计计算,酶联免疫吸附试验法检测雌二醇(Estradiol,E2)、孕酮(Progesterone,P)、卵泡刺激素(Follicle stimulating hormone,FSH)、黄体生成激素(Luteinizing Hormone,LH)水平。结果 干预后,模型组及实验组小鼠子宫重及子宫系数均高于正常组,实验组小鼠子宫重及子宫系数均低于模型组(P<0.05);干预后,模型组及实验组小鼠血清E2、P、FSH、LH水平均高于正常组,但实验组小鼠血清E2、P、FSH、LH水平均低于模型组(P<0.05)。结论 鲜天南星水提取物可对小鼠子宫纤维瘤起到一定的抑制作用,并能对E2、P、FSH、LH等激素水平进行调控,为子宫纤维瘤的临床治疗提供一定的理论依据,值得临床借鉴。 相似文献
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Estradiol, either from peripheral or central origin, activates multiple molecular neuroprotective and neuroreparative responses that, being mediated by estrogen receptors or by estrogen receptor independent mechanisms, are initiated at the membrane, the cytoplasm or the cell nucleus of neural cells. Estrogen-dependent signaling regulates a variety of cellular events, such as intracellular Ca2+ levels, mitochondrial respiratory capacity, ATP production, mitochondrial membrane potential, autophagy and apoptosis. In turn, these molecular and cellular actions of estradiol are integrated by neurons and non-neuronal cells to generate different tissue protective responses, decreasing blood-brain barrier permeability, oxidative stress, neuroinflammation and excitotoxicity and promoting synaptic plasticity, axonal growth, neurogenesis, remyelination and neuroregeneration. Recent findings indicate that the neuroprotective and neuroreparative actions of estradiol are different in males and females and further research is necessary to fully elucidate the causes for this sex difference. 相似文献
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《European journal of surgical oncology》2021,47(6):1316-1323
IntroductionBreast cancer co-occurred with thyroid cancer might be associated with thyroid hormone receptor (TR) and estrogen receptor (ER), but few have been reported. We aimed to investigate the expression and prognostic significance of ERs and TRs in such settings.Material and methodsTissue microarrays were constructed from 75 patients with breast and thyroid cancer (BC + TC) who were retrospectively recruited between 1999 and 2012 and 147 with breast cancer only (BC controls). The ERα, ERβ, TRα, and TRβ expression levels were analyzed by immunohistochemistry.ResultsTRα expression was more frequently observed in the BC + TC group than the BC control group both in the normal (51.5% vs 23.3%, respectively, p = 0.009) and cancer tissues (21.6% vs 6.8%, respectively, p = 0.001). The BC + TC group showed greater ERα-positivity in the cancer tissues (79.7% vs 58.7%, respectively, p = 0.002) than the BC control group. The degree of ERα- and TRα-positivity was unchanged by radioactive treatment or serum thyroid stimulating hormone levels. In the BC + TC group, ERα-positivity was associated with earlier disease stage I/IIA (81.0% vs 50.0%; p = 0.031) and lower recurrence rates (8.5% vs 40.0%; p = 0.002). TRα-positivity alone was not associated with any recurrence-free survival-related differences, and ERα- and TRα-negativity were associated with significantly shorter recurrence-free survival (p < 0.001).ConclusionEnhanced ERα and TRα expression in breast cancer is associated with thyroid cancer occurrence, and the observed association with prognosis suggests the possible role of ERs and TRs in the link between breast cancer and thyroid cancer. 相似文献
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