雌激素受体与乳腺癌内分泌治疗耐药的相关性研究

目的探讨雌激素受体β(ERβ)与乳腺癌内分泌治疗耐药的相关性。方法选取2010年1月至2015年6月间广东省惠州市中心人民医院收治的行乳腺癌改良根治术且接受他莫昔芬(TAM)内分泌治疗的100例早中期绝经后乳腺癌患者。检测乳腺癌患者ERβ表达情况,计算患者无肿瘤生存时间,比较不同ERβ表达患者间临床因素和预后的差异,分析ERβ表达差异与TAM内分泌治疗耐药的关系。结果 ERβ表达与原癌基因人类表皮生长因子受体2(HER-2)的表达相关,差异有统计学意义(P<0.05),与患者年龄、肿瘤大小、淋巴结转移、化疗及放疗无关,差异无统计学意义(P>0.05)。ERβ阳性表达患者无肿瘤生存率明显低于ERβ阴性表达患者,差异有统计学意义(P<0.05)。Cox多因素分析显示,ERβ阳性表达患者中,淋巴结转移是乳腺癌内分泌治疗预后不良的独立危险因素,差异有统计学意义(P<0.05)。结论 ERβ阳性表达在乳腺癌患者内分泌治疗耐药中具有重要作用,可能是导致患者预后不佳的危险因素之一。     

他莫昔芬对转染ERβ1基因的MCF-7细胞生长特性的影响

目的研究在不同处理因子作用下,外源基因ERβ1的表达对MCF-7乳腺癌细胞系生长特性的影响。方法利用脂质体转染方法将ERβ1真核表达载体pcDNA3.1-EGFPERβ1导入MCF-7乳腺癌细胞系。采用Western blot方法检测转染细胞中ERβ1的蛋白表达水平,筛选阳性克隆。以亲本细胞MCF-7为对照,分别在雌激素和雌激素受体拮抗剂他莫昔芬作用下观察细胞的生长特点。结果在转染ERβ1基因的MCF-7细胞系中,Western blot检测证实ERβ1的蛋白表达水平显著增高。在无处理因子的情况下,外源基因ERβ1在MCF-7细胞系中的表达能抑制细胞生长。与亲本细胞MCF-7细胞相比,转染ERβ1的MCF-7细胞对雌激素的敏感性下降,但对他莫昔芬的敏感性无明显变化。结论外源性ERβ1基因在MCF-7乳腺癌细胞中的稳定表达不增加对他莫昔芬的耐药性,但使之对雌激素的敏感性下降。     

miR-181d 对小细胞肺癌化疗药物敏感性的影响

目的:探讨miR-181d 在调节小细胞肺癌化疗敏感性中的作用。方法:通过QRT-PCR和Westernblot检测小细胞肺癌敏感细胞株H 69及耐药细胞株H 69AR中miR-181d 的差异表达。上调H 69AR细胞中的miR-181d 表达,检测miR-181d 和BCL 2表达;通过CCK 8 检测细胞对各种化疗药物（ADM、DDP 、VP- 16）的敏感性变化,QRT-PCR检测87例小细胞肺癌组织标本中miR-181d 表达,所有患者均接受EP方案（依托泊苷＋顺铂）化疗,分析其与患者预后及生存时间的关系。结果:miR-181d 在H 69AR及对化疗耐药患者中呈低表达,同时伴随着BCL 2 高表达（P < 0.001）。 上调miR-181d 能降低BCL 2 表达水平,增加H 69AR细胞对化疗药物（ADM、DDP 、VP- 16）的敏感性（P < 0.01）。 miR-181d 的表达与肿瘤的分期、对化疗药物的敏感性及生存时间相关（P <0.001）,高表达miR-181d 的患者总生存时间（OS）和无进展生存时间（DFS）较低表达者延长（P < 0.001）。 结论:miR-181d 可能在小细胞肺癌多药耐药中发挥着重要的作用,miR-181d 可望作为评价小细胞肺癌疗效的预测指标。      

miR-125a增强多西他赛对乳腺癌生长的抑制作用

背景与目的:研究表明miR-125a通过下调Her-2或者Her-3的表达抑制乳腺癌细胞生长,可能是指导乳腺癌治疗的靶点.本研究旨在观察miR-125a是否具有增强多西他赛对乳腺癌细胞株和裸鼠荷瘤模型的生长抑制作用.方法:转染miR-125a联合不同浓度多西他赛处理MCF-7和MDA-MB-231乳腺癌细胞株和MDA-MB-231乳腺癌裸鼠模型,观察细胞株和裸鼠接种肿瘤的生长情况.结果:miR-125a与多西他赛可协同抑制MDA-MB-231及MCF-7乳腺癌细胞株、MDA-MB-231乳腺癌裸鼠模型肿瘤的增殖,单纯转染miR-125a也可抑制MDA-MB-231及MCF-7乳腺癌细胞株的增殖.结论:miR-125a与多西他赛有协同抗乳腺癌作用,可成为乳腺癌靶向治疗的潜在靶点.     

miR-206通过调节ERα水平影响乳腺癌细胞MCF-7对他莫昔芬敏感度的初步研究

目的 探讨乳腺癌细胞株MCF-7中miR-206能否调节ERα表达水平并影响乳腺癌细胞对他莫昔芬的敏感度。方法 将miR-206 mimic、miR-206 inhibitor及相应阴性对照（miR-206 mimic NC、miR-206 inhibitor NC）分别转染乳腺癌MCF-7细胞,RT-PCR法检测转染后各组乳腺癌细胞中miR-206和ERα mRNA的表达量,用5 μg/ml他莫昔芬处理MCF-7细胞后,MTT法检测不同转染组细胞增殖情况。结果 miR-206 mimic组中乳腺癌细胞miR-206表达升高,ERα mRNA表达降低; miR-206 inhibitor组中乳腺癌细胞miR-206表达降低,ERα mRNA表达升高。他莫昔芬作用24 h后,miR-206 mimic组与阴性对照组（miR-206 mimic NC）的乳腺癌细胞增殖抑制差异无统计学意义（t=-1.169, P=0.276）;miR-206 inhibitor组的乳腺癌细胞增殖抑制明显强于阴性对照组（miR-206 inhibitor NC）（t=-3.054, P=0.016）。结论 下调miR-206表达可以增加ERα阳性乳腺癌细胞对他莫昔芬的敏感度。     

MiR-34a对乳腺癌Mcf-7／ADR细胞株多柔比星敏感性影响研究

目的：探讨乳腺癌细胞株MCF7和耐药株MCF7／ADR中miR-34a的表达差异及miR-34a对于多柔比星化疗敏感性的影响。方法：采用实时定量PCR技术检测MCF-7细胞及MCF-7／ADR细胞中miR-34a的表达差异。采用转染技术,以脂质体为载体,在MCF_7／ADR细胞株中过表达miR-34a后,检测其对于多柔比星耐药活性的影响,同时采用实时定量PCR技术和蛋白质印迹法技术检测靶基因的表达变化。结果：MCF-7细胞株和耐药株MCF-7／ADR中miR-34a的相对表达量分别为1．01±0．03和0．76±0．04,在耐药细胞株中呈现下调表达,P=0．007。MTT结果显示,MCF7及其耐药株MCF-7／ADR细胞多柔比星半数抑制浓度Ic5。分剐为（0,22±0．02）和（18．7±0．09）ftmol／L。对耐药株MCF-7／ADR过表达miR34a后,MCF-7／ADR细胞对多柔比星的ICso降低为（10．7士0．11）mol／L,明显增强此细胞株对于多柔比星的耐药敏感性。实时定量PCR结果显示,与转染阴性对照RNA相比,于耐药株MCF7／ADR细胞中转染miR--34a后耐药相关靶基因Bcl-2和CCNDl的mRNA水平分别降低了0．46±0．02（P=0．002）和0．33±0．02（P=0．008）。蛋白质印迹结果显示,过表达miR-34a后,可明显下调靶基因Bcl-2和CCNDl的表达。结论：上调表达miR34a可以增加耐药细胞株MCF-7／ADR对于多柔比星的耐药敏感性。     

维甲酸联合他莫昔芬对人乳腺癌细胞株作用的研究

目的:探讨他莫昔芬(TAM)与维甲酸(ATRA)联合对人乳腺癌他莫昔芬耐药株的作用.方法:在体外培养条件下,分别或联合应用ATRA和TAM作用于MCF-7人乳腺癌他莫昔芬耐药株(MCF-7/T)及敏感组(MCF-7/S).MTT比色法分析细胞生长抑制作用;用流式细胞仪(FCM)检测细胞周期分布、凋亡率及用药前后Bcl-2、Bax、Fas和FasL蛋白的变化.结果:TAM能抑制ER阳性MCF-7/S的生长,阻滞细胞周期于G0/G1期,并可诱导细胞凋亡,TAM不能抑制MCF-7/T的生长; ATRA预处理细胞24 h后,TAM抗乳腺癌细胞MCF-7/S的作用增强,且恢复了MCF-7/T对TAM的敏感性.ATRA与TAM联用后,MCF-7/T细胞Bcl-2蛋白表达下调,细胞Bax、Fas和FasL蛋白表达水平未见明显变化.结论:体外条件下,TAM通过影响细胞周期、诱导细胞凋亡而发挥抗ER阳性MCF-7/S作用;视黄酸能加强TAM对激素敏感细胞MCF-7/S的抗乳腺癌作用,恢复耐受细胞MCF-7/T对TAM的敏感性.同时恢复TAM对MCF-7/T的促凋亡作用.     

雌激素受体低表达乳腺癌的研究进展

细胞周期抑制剂改善了雌激素受体（estrogen receptor，ER）阳性乳腺癌患者的生存质量及预后。ER低表达作为ER阳性乳腺癌的一种类型，不同于ER高表达，其内分泌治疗效果差。随着检测技术的发展和耐药机制的研究，ER低表达患者的流行病学、临床病理特征以及治疗策略越来越多引起关注，本文将就ER低表达乳腺癌的研究进展进行综述。      

miR-27a在三阴性乳腺癌中的表达及其对细胞耐药的影响

目的:探讨miR-27a在三阴性乳腺癌（triple-negative breast cancer,TNBC）中的表达及其对细胞耐药的影响。方法:首先通过QRT-PCR检测TNBC细胞株及非TNBC细胞株中miR-27a及P-gp的差异表达;上调TNBC细胞中的miR-27a的表达,通过CCK8检测细胞对化疗药物敏感性的变化。同时收集TNBC患者化疗前后血液标本,将其分为化疗敏感组和化疗耐药组,QRT-PCR检测患者血液标本中miR-27a及P-gp的表达,分析miR-27a与乳腺癌患者预后相关性。结果:miR-27a在TNBC细胞株中的表达明显低于非TNBC细胞株,上调TNBC细胞株中miR-27a的表达能够降低P-gp的表达,增加细胞对化疗药物的敏感性,此外TNBC组中miR-27a的表达与患者组织学分级、临床分期及淋巴结转移相关（P<0.05）;在非TNBC组中miR-27a的表达与患者临床病理特征无明显相关性（P均＞0.05）。结论:miR-27a参与调节TNBC细胞耐药,miR-27a可作为评估乳腺癌化疗敏感性及临床预后的潜在靶基因。     

Relation of estrogen receptor expression to clonal growth and antiestrogen effects on human breast cancer cells

Expression of estrogen receptor (ER) was studied in the ER-positive human breast cancer cell line MCF-7 using immunoperoxidase staining with monoclonal antibodies to ER. Using a soft agar colony assay and liquid culture, effects of growth and the antiestrogen tamoxifen were examined. Heterogeneity in expression of ER was observed between different clones in the agar cultures as well as among cells within the same clone. Clonal expression of ER increased progressively with increasing cell number within a clone. At pharmacological doses, tamoxifen significantly reduced clonal growth but also markedly reduced the expression of ER within clones that grew despite the presence of the antiestrogen. These findings are consistent with the hypothesis that ER-positive colonies arise from ER-negative progenitors and that ER expression occurs along with differentiation of cells within clones. Furthermore, the findings are consistent with tamoxifen exerting its antineoplastic action beyond the level of the tumor stem cell. Such therapy would therefore be capable of suppression but not eradication of breast cancer clonal progenitors.     

A pilot study of the effects of short-term tamoxifen therapy on Ki-67 labelling index in women with primary breast cancer

In this study we demonstrate the change in estrogen receptor (ER) level and cell proliferation in human breast cancer after a short-term tamoxifen therapy. Ten pre- and post-treatment breast tumor samples were examined immunohistochemically using ER and Ki-67 antibodies. Before tamoxifen treatment, six (60%) of ten patients were positive for ER. Tamoxifen increased the ER level in one patient and decreased the level in 4 patients. There was no significant change in ER level by tamoxifen therapy. On the other hand, Ki-67 labelling index (LI) significantly decreased after tamoxifen treatment. When Ki-67 LI was analyzed according to ER level, there was no difference between pre- and post-tamoxifen treatment in ER-negative patients, however, a significant decrease of Ki-67 LI by tamoxifen treatment was seen in ER-positive patients. Patients who showed down-regulation of ER expression tended to show a decrease of Ki-67 LI after tamoxifen therapy. In conclusion, short-term tamoxifen therapy decreased the proliferation of breast cancer, in ER-positive breast tumor samples.     

Progesterone receptor expression is an independent prognostic variable in early breast cancer: a population-based study

Background:

Progesterone receptor (PR) expression assessment in early invasive breast cancer remains controversial. This study sought to re-evaluate PR expression as a potential therapeutic guide in early breast cancer; particularly in oestrogen receptor (ER)-positive, lymph node (LN)-negative disease.

Methods:

A population cohort of 1074 patients presenting to a single Cancer Centre over 4 years (2000–2004) underwent surgery for primary invasive breast cancer with curative intent. Prospective data collection included patient demographics, pathology, ER and PR expression, HER2 status, adjuvant chemotherapy and endocrine therapy. Progesterone receptor expression was compared with (all causes) overall survival (OS), breast cancer-specific survival (BCSS) and disease-free survival (DFS).

Results:

Overall survival was 71.0% and BCSS was 83.0% at median follow-up of 8.34 years. Absent PR expression was significantly associated with poorer prognosis for OS, BCSS and DFS (P<0.0001, log-rank), even within the ER-positive, LN-negative group (hazard ratio for BCSS 3.17, 95% CI 1.43–7.01) and was not influenced by endocrine therapy. Cox''s regression analysis demonstrated that PR expression was an independent prognostic variable.

Conclusion:

Absence of PR expression is a powerful, independent prognostic variable in operable, primary breast cancer even in ER-positive, LN-negative patients receiving endocrine therapy. Absence of PR expression should be re-evaluated as a biomarker for poor prognosis in ER-positive breast cancer and such patients considered for additional systemic therapy.     

E2F7 overexpression leads to tamoxifen resistance in breast cancer cells by competing with E2F1 at miR-15a/16 promoter

About 50–70% of breast cancers are estrogen receptor α (ERα) positive and most of them are sensitive to endocrine therapy including tamoxifen. However, one third of these patients will eventually develop resistance and relapse. We found that the expression of miR-15a and miR-16 were significantly decreased in tamoxifen resistant ER positive breast cancer cell lines. Exogenous expression of miR-15a/16 mimics re-sensitized resistant cells to tamoxifen by inhibiting Cyclin E1 and B cell lymphoma-2 (Bcl-2) to induce cell growth arrest and apoptosis respectively. Further, we identified that a repressive member of E2F family, E2F7, was responsible for the suppression of miR-15a/16 cluster by competing with E2F1 for E2F binding site at the promoter of their host gene DLEU2. Moreover, high expression of E2F7 is correlated with high risk of relapse and poor prognosis in breast cancer patients receiving tamoxifen treatment. Together, our results suggest that overexpression of E2F7 represses miR-15a/16 and then increases Cyclin E1 and Bcl-2 that result in tamoxifen resistance. E2F7 may be a valuable prognostic marker and a therapeutic target of tamoxifen resistance in breast cancer.     

Microtubule-associated protein-tau is a bifunctional predictor of endocrine sensitivity and chemotherapy resistance in estrogen receptor-positive breast cancer.

PURPOSE: The clinical outcome for patients with breast cancer is influenced by the metastatic competence of the cancer and its sensitivity to endocrine therapy and chemotherapy. A molecular marker may be prognostic of outcome or predictive of response to therapy, or a combination of both. EXPERIMENTAL DESIGN: We examined separately the prognostic and predictive values of tau mRNA expression in estrogen receptor (ER)-positive primary breast cancers in three patient cohorts. We used gene expression data from 209 untreated patients to assess the pure prognostic value of tau, data from 267 patients treated with adjuvant tamoxifen to assess predictive value for endocrine therapy, and data from 82 patients treated with preoperative paclitaxel followed by 5-fluorouracil, doxorubicin, and cyclophosphamide (paclitaxel/FAC) to assess predictive value for chemotherapy response. Wilcoxon rank sum test was used to compare tau expression between different outcome groups. RESULTS: Higher tau mRNA expression showed borderline nonsignificant association with better prognosis in the absence of systemic adjuvant therapy. Higher tau mRNA expression was significantly associated with no recurrence (at 5 and 10 years, P = 0.005 and P = 0.05, respectively) in patients treated with tamoxifen, indicating a predictive value for endocrine therapy. Tau expression was significantly lower in patients who achieved pathologic complete response to paclitaxel/FAC chemotherapy (P < 0.001). CONCLUSION: This study suggests that high tau mRNA expression in ER-positive breast cancer indicates an endocrine-sensitive but chemotherapy-resistant disease. In contrast, low tau expression identifies a subset of ER-positive cancers that have poor prognosis with tamoxifen alone and may benefit from taxane-containing chemotherapy.     

The prognostic biomarkers HOXB13, IL17BR, and CHDH are regulated by estrogen in breast cancer.

PURPOSE: We previously identified three genes, HOXB13, IL17BR, and CHDH, that strongly predict clinical outcome in estrogen receptor (ER)-positive breast cancer patients receiving tamoxifen monotherapy. The biological mechanisms linking these genes to estrogen signaling and tamoxifen response in breast cancer remain to be determined. EXPERIMENTAL DESIGN: In a consecutive series of 148 ER-positive and ER-negative breast cancers, HOXB13, IL17BR, and CHDH gene expression was measured by quantitative real-time PCR and correlated with ER, PR, and HER2 expression. The role of estrogen and ER in the regulation of these three genes was assessed in several ER-positive and ER-negative breast cancer cell lines. RESULTS: In primary breast tumors, HOXB13 expression correlated negatively, and IL17BR and CHDH expression correlated positively, with ER status, and all three genes exhibited an ER-dependent correlation pattern with HER2 status that differs from PR and PS2, two canonical estrogen-regulated genes. Results using breast cancer cell lines show that these genes are regulated by estradiol in an ER-dependent manner, and that this regulation is abrogated by tamoxifen. CONCLUSIONS: HOXB13, IL17BR, and CHDH are estrogen-regulated genes, but their pattern of correlation with known positive (ER, PR) and negative (HER2) predictors of tamoxifen response differs from canonical ER signature genes. These results provide a biological rationale for the prognostic utility of these three genes in early-stage ER-positive breast cancer and for their potential to predict anti-estrogen resistance.     

Differential sensitivity of human breast cancer cell lines to the growth-inhibitory effects of tamoxifen

In eight estrogen receptor (ER)-positive breast cancer cell lines (including three sublines of MCF-7) and five ER-negative breast lines, the action of the nonsteroidal antiestrogen, tamoxifen, was studied, and the concentrations of ER and antiestrogen binding site were measured. The concentration of antiestrogen binding site was significantly [P less than 0.005] greater in ER-positive cells [236,600 +/- 29,900 (SE) sites/cell] than in ER-negative cell lines [66,600 +/- 16,800 sites/cell]. In ER-positive cell lines, a cell cycle phase-specific growth-inhibitory effect, 20% inhibitory dose less than 0.1 to 1.0 microM, was seen which was shown for some representative cell lines to be estrogen reversible. Within this group of cell lines, the degree of tamoxifen-induced inhibition of growth correlated with control population doubling time, but not ER or antiestrogen binding site concentration. The changes in cell cycle kinetic parameters characteristic of all ER-positive lines were a decrease in percentage of S-phase cells and a corresponding increase in percentage of G0-G1 cells. In all cell lines, 5 to 12.5 microM tamoxifen caused cytotoxicity, and this was shown to be estrogen-irreversible in 3 representative cell lines; moreover, estradiol synergistically enhanced the cytotoxic effects of tamoxifen under some experimental conditions. The cell cycle effects of tamoxifen in three ER-negative cell lines (Hs0578T, MDA-MB-231, MDA-MB-330) were decreased proportions of G0-G1 cells with an increase in percentages of S and G2+M cells. These results implied that the mechanism of tamoxifen cytotoxicity may differ in ER-positive and ER-negative breast cancer cells. However, although the ER-negative BT-20 line was much less sensitive to tamoxifen than were the ER-positive cells, growth inhibition and cytotoxicity in this line were associated with a slight decrease in percentage of S-phase cells. These results confirm that ER-positive breast cancer cells are more sensitive (4- to greater than 75-fold) than ER-negative breast cells to the growth-inhibitory effects of tamoxifen and demonstrate that, in all ER-positive cells, growth inhibition and cytotoxicity are accompanied by characteristic changes in cell cycle kinetic parameters. In contrast, different mechanisms may be involved in the effects of tamoxifen on different ER-negative cell lines.     

Mechanisms of FGFR3 actions in endocrine resistant breast cancer

Although endocrine therapy has dramatically improved the treatment of breast cancer therapeutic resistance and tumour recurrence occurs, even in estrogen receptor (ER) positive cases. Identifying and understanding the molecular mechanisms which underpin endocrine resistance is therefore important if future therapeutic strategies are to be developed. Members of the fibroblast growth factor (FGF) and fibroblast growth factor receptor (FGFR) families have been implicated in breast cancer development and progression. Our results demonstrate that culture of michigan cancer foundation - 1 (MCF)7 cells with FGF1 results in reduced sensitivity to tamoxifen in vitro. Furthermore, our tissue microarray expression data demonstrates that FGFR3 expression is increased in tamoxifen resistant breast tumours. To confirm that activation of FGFR3 reduced sensitivity to tamoxifen we used an inducible activation system and a constitutively active mutant of FGFR3 expressed in MCF7 cells. Activation of FGFR3 reduced sensitivity to tamoxifen and Fulvestrant but did not lead to phosphorylation of ER demonstrating that FGFR3 does not feedback to modulate ER activity. FGFR3 activation in MCF7 cells stimulated activation of the mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) signalling pathways, both of which have been implicated in tamoxifen resistance in breast cancer. Furthermore, our data indicates that activation of phospholipase C gamma is a key-signalling event regulating MAPK and PI3K activation and that its activation reduces sensitivity to tamoxifen. Therefore, we hypothesise that FGFRs could play an integral part, not only in breast cancer development but also in resistance to endocrine-therapy.     

PELP-1 regulates adverse responses to endocrine therapy in Estrogen Receptor (ER) positive breast cancer

Introduction: Endocrine therapy has played an important role in the management of ER positive breast cancer over recent decades. Despite this, not all patients respond equally to endocrine intervention, which can lead to resistance, associated disease relapse and progression. Previous reports suggest that endocrine agents themselves may induce an invasive phenotype in ER positive breast cancers with low/aberrant expression of E-cadherin. Here we investigate this phenomenon further and provide data supporting a role for the ER co-receptor, PELP-1, in mediating an adverse response to endocrine agents.Materials and Methods: The effects of tamoxifen, fulvestrant and estrogen withdrawal (as a model for aromatase inhibitor therapy) on the invasive and migratory capacity of endocrine-sensitive MCF-7 and T47D cells, in the presence or absence of functional E-cadherin and/or PELP-1 (using siRNA knockdown), was assessed via Matrigel invasion and Boyden chamber migration assays. The effects of these endocrine therapies alongside E-cadherin/PELP-1 modulation on cell proliferation were further assessed by MTT assay. Western blotting using phospho-specific antibodies was performed to investigate signalling pathway changes associated with endocrine-induced changes in invasion and migration.Results: Both tamoxifen and fulvestrant induced a pro-invasive and pro-migratory phenotype in ER positive breast cancer cells displaying a high basal expression of PELP-1, which was augmented in the context of poor cell-cell contact. This process occurred in a Src-dependent manner with Src inhibition reversing endocrine induced invasion/migration. While this adverse response was observed using both tamoxifen and fulvestrant therapy, it was not observed under conditions of estrogen withdrawal.Conclusions: Our data confirms previous reports that anti-estrogens induce an adverse cell phenotype in ER+ breast cancer, particularly in the absence of homotypic cell contact. These results implicate E-cadherin and PELP-1 as potential biomarkers when deciding upon optimum adjuvant endocrine therapy, whereby tumours with high PELP-1/low E-cadherin expression may benefit from estrogen withdrawal therapy via aromatase inhibition, as opposed to ER modulation/antagonism.     

雄激素受体与乳腺癌内分泌耐药的研究进展

乳腺癌是女性最常见的恶性肿瘤。其中雌激素受体（ER）阳性乳腺癌对内分泌治疗敏感,通过规范的内分泌治疗,患者复发及死亡风险显著降低。但是,内分泌耐药的出现成为临床治疗中最大的障碍。雄激素受体（AR）在ER阳性乳腺癌中广泛表达,与ER之间存在串扰,影响乳腺癌发展、内分泌耐药及预后。本文就AR在ER阳性乳腺癌中的作用机制、预后及内分泌治疗影响,尤其是内分泌耐药的相关研究进展进行综述。