4-Hydroxyandrostenedione treatment for postmenopausal patients with advanced breast cancer

We have treated 128 postmenopausal women with advanced breast cancer with 4-hydroxyandrostenedione. Of these, 118 were assessable for toxicity and 100 for response to treatment. Response to therapy was seen in 34% of patients and stabilization of disease in 12 patients. Three dose regimens were used (500 mg intramuscularly weekly; 250 mg intramuscularly every 2 weeks; and 500 mg orally daily). There was no difference in response in these three groups. Side effects were minimal and local reaction to injected drug was seen in 13% of patients. The sole severe side effect observed was neutropenia which was transient and reversible on discontinuing therapy. 4-Hydroxyandrostenedione is an effective nontoxic agent in the treatment of breast cancer.     

Aromatization inhibition alone or in combination with GnRH agonists for the treatment of premenopausal breast cancer patients.

Aromatase inhibition in postmenopausal women causes a marked fall in the plasma levels of oestrogens and is an effective treatment for breast cancer, however, trials with aminoglutethimide found that this aromatase inhibitor was ineffective in suppressing plasma oestrogen levels in premenopausal breast cancer patients. We found that the more potent inhibitor, 4-hydroxyandrostenedione (4-OHA), which can suppress oestrogen synthesis in rodents and non-human primates with intact ovarian function, was also unsuccessful as an oestrogen suppressant in premenopausal women at its maximum tolerated dose (500 mg/week i.m.). GnRH agonists are effective suppressants of ovarian oestrogen synthesis but oestrogen production from peripheral sites is unaffected. Our studies of a combination of the GnRH agonist goserelin and 4-OHA demonstrated that the combination caused greater oestrogen suppression than goserelin alone and led to objective clinical response in 4/6 breast cancer patients after their relapse from treatment with goserelin as a single agent. The combination of a GnRH agonist and an aromatase inhibitor should be subjected to clinical trials.     

Aromatase inhibitors: basic and clinical studies

Application of aromatase inhibitors to the treatment of conditions in which estrogen plays, a role is discussed. Studies in vitro demonstrate that 4-hydroxyandrostenedione (4-OHA) is a potent inhibitor of aromatase. The compound reduces ovariant estrogen production and causes regression of carcinogen (DMBA)-induced mammary tumors in the rat. In the rhesus monkey, 4-OHA was also shown to inhibit peripheral aromatization. To date 58 postmenopausal breast cancer patients with advanced metastatic disease have received 500 mg im weekly while 31 patients received 250 mg 4-OHA orally per day. Estradiol levels were significantly reduced in all patients from a mean of 7.2 + 0.8 pg/ml to 2.8 + 0.3 pg/ml. Of patients receiving 4-OHA im 27% had partial or complete responses and in 10% of patients the disease was stabilized. Similar responses occurred in the patients receiving 4-OHA orally. These results suggest that 4-OHA is effective and that this compound and other aromatase inhibitors could be valuable new additions to the treatment of breast cancer.     

老年乳腺癌患者的临床病理特点及其辅助治疗模式的研究

目的:探讨老年乳腺癌患者的临床病理特点及其辅助治疗模式,为老年乳腺癌患者的临床治疗提供参考。方法:选取2008年1月-2012年1月期间我院收治的50例老年乳腺癌患者作为研究对象,同时选取同期收治的50例中青年乳腺癌患者,比较两组患者的临床病理特征,并采用新辅助内分泌疗法治疗本组50例老年乳腺癌患者,治疗4个月后观察治疗效果。结果:老年乳腺癌患者的病灶5cm比例以及ER和PR阳性率均明显高于中青年患者,两组患者数据比较差异有统计学意义(P0.05);老年乳腺癌患者的淋巴结转移率、Ki67阳性率以及HER-2阳性率均低于中青年患者,两组患者数据比较差异均有统计学意义(P0.05);本组50例老年乳腺癌患者治疗总有疗效为82.0%,ER、PR均为阳性患者的治疗有效率为90.0%,明显高于ER和PR非双阳性患者(76.9%,57.1%),数据比较差异均有统计学意义(P0.05);TNM I期患者的治疗有效率为93.8%,明显高于TNM II期(76.9%)或TNM III期患者(20.0%),数据比较差异均有统计学意义(P0.05)。患者在治疗期间均未出现严重不良反应。结论:老年乳腺癌患者的生物学行为较好,病灶大、淋巴转移率低以及ER和PR阳性率高;新辅助内分泌治疗老年乳腺癌患者,尤其对ER、PR均为阳性以及TNM分期低的患者临床效果安全有效,不良反应发生率低,值得临床推广应用。     

Development and evolution of therapies targeted to the estrogen receptor for the treatment and prevention of breast cancer

This article describes the origins and evolution of "antiestrogenic" medicines for the treatment and prevention of breast cancer. Developing drugs that target the estrogen receptor (ER) either directly (tamoxifen) or indirectly (aromatase inhibitors) has improved the prognosis of breast cancer and significantly advanced healthcare. The development of the principles for treatment and the success of the concept, in practice, has become a model for molecular medicine and presaged the current testing of numerous targeted therapies for all forms of cancer. The translational research with tamoxifen to target the ER with the appropriate duration (5 years) of adjuvant therapy has contributed to the falling national death rates from breast cancer. Additionally, exploration of the endocrine pharmacology of tamoxifen and related nonsteroidal antiestrogen (e.g. keoxifene now known as raloxifene) resulted in the laboratory recognition of selective ER modulation and the translation of the concept to use raloxifene for the prevention of osteoporosis and breast cancer. However, the extensive evaluation of tamoxifen treatment revealed small but significant side effects such as endometrial cancer, blood clots and the development of acquired resistance. The solution was to develop drugs that targeted the aromatase enzyme specifically to prevent the conversion of androstenedione to estrone and subsequently estradiol. The successful translational research with the suicide inhibitor 4-hydroxyandrostenedione (known as formestane) pioneered the development of a range of oral aromatase inhibitors that are either suicide inhibitors (exemestane) or competitive inhibitors (letrozole and anastrozole) of the aromatase enzyme. Treatment with aromatase inhibitors is proving effective and is associated with reduction in the incidence of endometrial cancer and blood clots when compared with tamoxifen and there is also limited cross resistance so treatment can be sequential. Current clinical trials are addressing the value of aromatase inhibitors as chemopreventive agents for postmenopausal women.     

Point mutation of estrogen receptor (ER) in the ligand-binding domain changes the pharmacology of antiestrogens in ER-negative breast cancer cells stably expressing complementary DNAs for ER.

The antiestrogen tamoxifen is used in the treatment of hormone-responsive breast cancer. However, therapeutic failure has frequently been observed in both patients and animal models after long term treatment. We have studied the effect of a point mutation that leads to the substitution of Val for Gly at codon 400 in the ligand-binding domain of the estrogen receptor (ER) on estrogenic and antiestrogenic activities of 4-hydroxytamoxifen (4-OHT) and its derivatives. Stable ER transfectants derived from MDA-MB-231 CL10A, an ER-negative breast cancer cell line, have been used in these studies. 4-OHT and its fixed ring derivatives showed more estrogen-like activity in ER transfectants than in MCF-7, an ER-positive breast cancer cell line. In this study, 4-OHT was a partial agonist of cell growth in the transfectant S30 cells, which express the wild-type ER. However, it was a full agonist in the mutant ER transfectant ML alpha 2H, which expressed ER with Val at codon 400. The increased estrogenic activity of 4-OHT in ML alpha 2H cells was not due to the preferential isomerization of trans 4-OHT to cis 4-OHT, since the nonisomerizable fixed ring trans 4-OHT was a partial agonist for cell growth in S30 cells and was a full agonist in ML alpha 2H cells. Transient transfection using a reporter plasmid containing an estrogen response element demonstrated that fixed ring trans 4-OHT had estrogenic activity in ML alpha 2H cells.(ABSTRACT TRUNCATED AT 250 WORDS)     

Response of estrogen receptor-positive breast cancer tumorspheres to antiestrogen treatments

Estrogen signaling plays a critical role in the pathogenesis of breast cancer. Because the majority of breast carcinomas express the estrogen receptor ERα, endocrine therapy that impedes estrogen-ER signaling reduces breast cancer mortality and has become a mainstay of breast cancer treatment. However, patients remain at continued risk of relapse for many years after endocrine treatment. It has been proposed that cancer recurrence may be attributed to cancer stem cells (CSCs)/tumor-initiating cells (TICs). Previous studies in breast cancer have shown that such cells can be enriched and propagated in vitro by culturing the cells in suspension as mammospheres/tumorspheres. Here we established tumorspheres from ERα-positive human breast cancer cell line MCF7 and investigated their response to antiestrogens Tamoxifen and Fulvestrant. The tumorsphere cells express lower levels of ERα and are more tumorigenic in xenograft assays than the parental cells. Both 4-hydroxytamoxifen (4-OHT) and Fulvestrant attenuate tumorsphere cell proliferation, but only 4-OHT at high concentrations interferes with sphere formation. However, treated tumorsphere cells retain the self-renewal capacity. Upon withdrawal of antiestrogens, the treated cells resume tumorsphere formation and their tumorigenic potential remains undamaged. Depletion of ERα shows that ERα is dispensable for tumorsphere formation and xenograft tumor growth in mice. Surprisingly, ERα-depleted tumorspheres display heightened sensitivity to 4-OHT and their sphere-forming capacity is diminished after the drug is removed. These results imply that 4-OHT may inhibit cellular targets besides ERα that are essential for tumorsphere growth, and provide a potential strategy to sensitize tumorspheres to endocrine treatment.     

The Preliminary Study of 16α-[18F]fluoroestradiol PET/CT in Assisting the Individualized Treatment Decisions of Breast Cancer Patients

Objective

To evaluate the clinical value of 16α-[18F]fluoroestradiol (18F-FES) PET/CT in assisting the individualized treatment decisions of breast cancer patients.

Methods

Thirty-three breast cancer patients, who underwent both 18F-FES and 18F-FDG PET/CT from July 2010 to March 2013 in our center, were enrolled in this preliminary study. All the patients used 18F-FES PET/CT as a diagnostic tool with a clinical dilemma. We used the maximum Standardized Uptake Value (SUVmax) to quantify ER expression and a cutoff value of 1.5 to dichotomize results into ER positive and negative lesions. All patients were clinically followed up at least 6 months.

Results

In evaluating equivocal lesions on conventional work-up group (n = 4), three lung lesions and another iliac lesion were enrolled. As for three lung lesions, 18F-FES PET/CT showed one lesion with high uptake, which suggested it was an ER positive metastasis. The other two lesions were 18F-FES negative, which meant an ER negative metastasis or secondary primary tumor. Additionally, one iliac lesion was detected by MRI. 18F-FDG uptake was high at the suspected lesion, whereas 18F-FES uptake was absent; In predicting origin of metastasis group (n = 2), two breast cancer patients had secondary primary tumors were collected. They were 18F-FES negative, which showed low possibility of metastasis from breast cancer and they were all confirmed by biopsy. In detecting ER status in metastasis group (n = 27), 18F-FES PET/CT showed increased 18F-FES uptake in all metastatic lesions in 11 patients; absent in all lesions in 13 patients; and the remaining 3 patients had both 18F-FES positive and negative lesions. Totally, on the basis of the 18F-FES PET/CT results, we found changes in the treatment plans in 16 patients (48.5%, 16/33).

Conclusions

18F-FES PET/CT could assess the entire tumor volume receptor status; therefore, it may be used to assist the individualized treatment decisions of breast cancer patients.     

Aromatase inhibitors and hormone-dependent cancers

Aromatase (estrogen synthetase) occurs in a variety of tissues. Using immunocytochemistry, we have recently located this enzyme in cellular compartments of several types of human tissue. Furthermore, we found the mRNA was located in the same structures where tested. As both gonadal and peripherally formed estrogen contribute to growth of hormone sensitive cancers, we have developed aromatase inhibitors to block synthesis of this hormone. We have determined that 4-hydroxyandrostenedione (4-OHA) selectively inhibits aromatase activity in ovarian and peripheral tissues and reduces plasma estrogen levels in rat and non-human primate species. 4-OHA was also found to inhibit gonadotropin levels and reduce estrogen and progesterone receptor levels in treated animals. The mechanism of these effects appear to be associated with the weak androgenic activity of the compound. These effects together with aromatase inhibition may result in a synergistic response reducing estrogen production and action. In postmenopausal women, estrogens are mainly of peripheral origin. When postmenopausal breast cancer patients were administered either daily oral or parenteral weekly treatment with 4-OHA at doses that did not affect their gonadotropin levels, plasma estrogen concentrations were significantly reduced. Complete or partial response to treatment occurred in 34% of 100 patients with advanced breast cancer, while the disease was stabilized in 12%. These results indicate that 4-OHA is of benefit in postmenopausal patients with advanced disease who have relapsed from prior hormonal therapies, and that steroidal inhibitors may be of value in premenopausal patients.     

Aromatase and other inhibitors in breast and prostatic cancer

Estrogens have an important role in the growth of breast and other hormone-sensitive cancers. We have shown that 4-hydroxyandrostenedione (4-OHA) selectively blocks estrogen synthesis by inhibiting aromatase activity in ovarian and peripheral tissues and reduces plasma estrogen levels in rat and non-human primate species. In postmenopausal men and women, estrogens are mainly of peripheral origin. When postmenopausal breast cancer patients were administered either by daily oral or parenteral weekly treatment with 4-OHA, plasma estrogen concentrations were significantly reduced. Complete or partial response to treatment occurred in 34% of 100 patients with advanced breast cancer, while the disease was stabilized in 12%. We recently studied the effects of 4-OHA and other aromatase inhibitors, 10-propargylestr-4-ene-3,17-dione (PED) and imidazo[1,5-]3,4,5,6-tetrahydropyrin-6-yl-(4-benzonitrile) (CGS 16949A) as well as 5-reductase inhibitors, N,N-diethyl-4-methyl-3-oxo-4-aza-5-androstane-17β-carboxyamide (4-MA) and 17β-hydroxy-4-aza-4-methyl-19norandrost-5-en-3-one (L651190) in prostatic tissue from 11 patients with prostatic cancer and six patients with benign prostatic hypertrophy (BPH), and from normal men at autopsy. We attempted to measure aromatase activity in tissue incubation by quantitating ³H₂O released during aromatization of androstenedione or testosterone labeled at the C-1 position. The amount of ³H₂O released from all samples was at least twice that of the heat inactivated tissue samples. The ³H₂O release was significantly inhibited by 4-OHA and 4-MA, but not by the other aromatase inhibitors. However, when HPLC and TLC were used to isolate steroid products, no estrone or estradiol was detected in the incubates. Furthermore, no aromatase mRNA was detected following amplification by PCR. The 4-OHA was found to inhibit 5-reductase in both BPH and cancer tissue, although to a lesser extent than 4-MA. The other aromatase inhibitors were without effect. Although a mechanism involving intraprostatic aromatase is not likely, inhibitors may act to reduce peripherally-formed estrogens. In postmenopausal breast cancer, the results indicate that 4-OHA is of significant benefit.     

Estrogen receptor alpha (ERα) promoter methylation status in tumor and serum DNA in Egyptian breast cancer patients

Background

Status of DNA methylation is one of the most common molecular alterations in human neoplasia. Because it is possible to detect these epigenetic alterations in the bloodstream of patients, we investigated the aberrant DNA methylation status of estrogen receptor alpha (ERα) in patient pretherapeutic sera and tissue.

Materials and methods

In this case control study the patient series consisted of 120 sporadic primary breast cancer cases and 100 patients with benign breast lesion. ER3, ER4, and ER5 primers were used for methylation-specific polymerase chain reaction (MSP) to analyze the CpG methylation of promoter region of ERα gene. Correlation between ER3, ER4, and ER5 methylation and clinicopathological characteristics of the patients was investigated.

Result

The methylation status of ER3, ER4 and ER5 was 65%, 26.7% and 61.7% in tissue respectively and 57.5%, 21.7% and 55.8% in serum respectively. The concordance between tumor and serum DNA methylation was 80%, 72% and 92% for ER3, ER4 and ER5 respectively.

Conclusions

This study demonstrated the potential utility of serum DNA methylation of ERα gene promoter as a non-invasive diagnostic and/or prognostic marker in patients with breast cancer.     

The Impact of Androgen Receptor Expression on Breast Cancer Survival: A Retrospective Study and Meta-Analysis

Recent studies have highlighted the role of androgen receptor (AR) as a prognostic biomarker of breast cancer. However, its predictive role in disease free survival (DFS) and overall survival (OS) still remains inconclusive. The present study aimed to retrospectively investigate the association between AR and survival outcomes in breast cancer and also identify this association by a meta-analysis of published researches. Clinical data from 109 patients with breast cancer, who underwent surgery at Ruijin Hospital, Shanghai, were retrospectively analyzed for immunohistochemical AR expression measured by tissue microarray. For meta-analysis, articles available in Pubmed on the relationship between AR and breast cancer outcomes were included. Data obtained from both were combined and analyzed. Women with AR positive tumors in the retrospective study had a significantly better DFS (HR 0.24, 95% CI 0.07-0.88) and OS (HR 0.19, 95% CI 0.04-0.85) than women with AR negative ones. Meta-analysis showed that AR expression in breast tumors was an indicator of better DFS (HR 0.52, 95% CI 0.43-0.64). In subgroup analysis, AR could predict DFS outcome in estrogen receptor (ER) positive (HR 0.45, 95% CI 0.34-0.59), ER negative (HR 0.42, 95% CI 0.26-0.67), and triple negative breast cancer (HR 0.40, 95% CI 0.23-0.69). Moreover, in ER positive breast cancer patients, the expression of AR could predict better OS (HR 0.39, 95% CI 0.19-0.82). The present analysis indicated that AR expression was associated with lower risk of recurrence in patients with all breast cancer types and better OS in cases with ER positive.     

Estrogen and progesterone receptor status in primary breast cancer--a study of 11,273 patients from the year 1990 to 2002

The aim of this study was to gain insight of the breast cancer hormone receptor status of our patients, its stratification according to age as well as its changes during the period of 13 years. 11,273 patients with primary breast cancer from several towns in Croatia were included in this study. Patients' tumour specimens were collected from 1990 to 2002 and were analysed on estrogen (ER) and progesterone (PR) receptors in the Laboratory of the Department of Medical Oncology, University Hospital Centre Zagreb. More than half of our breast cancer patients had ER positive tumours (54.3%). We observed ER + tumours increased with age continuously, with highest percentage in the age group of 70 to 79 years (68.1%). Similarly, proportion of PR + tumours was higher in the older age groups, being the highest between 40 and 49 years (55.9%). During 13 years of the study, the increase in frequency and proportion of ER + tumours was observed (from 52% in 1990 to 62% in 2002) and decrease of PR + tumours (56% to 53%). We confirm previous findings that the risk of hormone dependent breast cancer increases with aging. Risk of ER + breast cancer increased for 10% from 1990 to 2002 and PR + tumours decreased for 3.5% in the same period.     

Agreement of self-reported hormone receptor status with cancer registry data in young breast cancer patients

BackgroundThough breast cancer subtype is a key determinant of treatment choice and prognosis, few studies have assessed breast cancer patients’ knowledge of estrogen and progesterone receptor (ER/PR) status.MethodsWomen diagnosed with invasive breast cancer at age 18–64 years in 2007 were recruited from the Pennsylvania Cancer Registry, and mailed a questionnaire that asked respondents to identify their ER/PR status. There were 2191 respondents included in the analysis. Agreement between self-report and cancer registry ER/PR status was assessed using kappa statistic. Logistic regression was used to assess the association of demographic, socioeconomic, and tumor factors with inaccurate self-report of ER/PR status.ResultsFifty-nine percent of respondents reported ER/PR positive status, 15% reported ER/PR negative status, 17% responded ‘don’t know’, and 9% did not respond. Overall, there was 69% agreement between self-report and cancer registry data, and fair agreement as measured by kappa (0.36). After excluding women who did not know or did not report their ER/PR status, there was 93% agreement, and substantial agreement as measured by kappa (0.76). Women who were older, non-white, less educated, lower income, and had ER/PR negative disease were significantly more likely to inaccurately report their ER/PR status.ConclusionsThough a significant proportion of women do not know their hormone receptor status, women who reported their ER/PR status were accurate. Our results suggest room for improvement in patient knowledge of tumor subtypes, but also that self-reported ER/PR status may be a useful surrogate when medical record or cancer registry data is unavailable.     

An investigation of cut-points for primary breast cancer oestrogen and progesterone receptor assays

Oestrogen and progesterone receptor (ER and PgR) assay values are frequently used in medical decision-making for breast cancer patients. We have proposed statistical standardization of receptor assay values to improve inter-laboratory comparability, and now report the use of standardized log units (SLU) to investigate the effects of ER and PgR cut-points on time to first recurrence outside the breast (DFS). Between 1980 and 1986, there were 678 primary breast cancer patients treated at the Henrietta Banting Breast Centre (HBBC). The effects of ER and PgR cut-points were examined with multivariate analyses considering the variables: age, tumour size, nodal status, weight and adjuvant treatment. We considered receptor assay cut-points ranging from −1.0 to +1.0 SLU (ER between 7 and 166 fmol/mg protein; PgR between 7 and 181 fmol/mg protein). PgR was included in the multivariate prognostic models more often than ER, although patients had a better prognosis with both larger ER and PgR values. There was no best cut-point for ER or PgR, and there was strong evidence that ER and PgR should be considered as continuous rather than dichotomous (negative, positive) variables. Patient prognosis should also be more comparable with SLU.     

A Nation-Wide Multicenter 10-Year (1999-2008) Retrospective Clinical Study of Endocrine Therapy for Chinese Females with Breast Cancer

Endocrine therapy (ET) is one of the main systemic treatments for patients with breast cancer. To our knowledge, few studies have addressed the performance of ET or relevant influencing factors in cancer treatment in China. By retrospectively analyzing the clinicopathological data on breast cancer collected from representative hospitals of 7 traditional areas in China in one random month from each year between year 1999 and 2008, we found that: 1) The rate of the use of hormone receptor (HR) testing was 83.8% (3529/4211), with the estrogen receptor-positive (ER+) rate and/or the progesterone receptor-positive (PR+) rate being 67.9% (2395/3529), and the ER-PR rate being 32.1% (1134/3529). 2) Of the 1599 patients who had received ET, 999 patients (58.3%) were premenopausal while 600 (41.7%) were postmenopausal; 1598 patients received adjuvant hormonal therapy (AHT), whereas only 1 patient received palliative therapy. The medications mainly administered to patients were anti-estrogen agents (80.3% [1283/1598]), followed by AIs (15.5% [248/1598]). Of the 1598 patients receiving AHT, 1416 patients (88.6%) were positive for ER and/or PR, while 75 (4.7%) were negative for both and 108 patients (6.7%) had unknown HR status. The ratio of the use of endocrine therapy for breast cancer patients with ER+ and/or PR+ status was 60.0% (1416/2395). 3) Results from the logistic regression analysis revealed that geography, occupations, and history of chemotherapy and surgery were dependent factors affecting the application of ET in breast cancer treatment in China (P<0.001). In conclusion, the use of ET on Chinese women with breast cancer is increasingly and gradually accounted into the standardized process. Economic status, occupations, and history of chemotherapy and surgery were key factors affecting the application of ET. People residing in developed areas, engaging in mental labour, having history of chemotherapy and surgery are susceptible to accept ET.     

Detection of the level of estrogen receptor and functional variants in human breast cancers by novel assays

The level of estrogen receptor (ER) is a key determinant for the management of ER-positive [ER(+)] breast cancer patients. Growth of many human breast cancers is regulated by estrogen (E2) and progesterone (Pr). Generally, the ER in ER(+) breast cancer patients is targeted for therapy with antihormones. However 40% of ER(+) patients do not respond to antihormone therapy. Thus, the identification of antihormone resistant ER(+) breast cancers is essential for therapeutic predictions. Although 3H-E2 binding and immunodetection can identify ER, these procedures do not assess the functional state of the receptor molecule. In this study we describe a novel and rapid assay for the detection of ER and its functional state on the basis of the downstream interaction with its response element (ERE) based on the preferential binding of DNA-protein complex (ERE-ER) to a nitrocellulose membrane (NMBA). This method permits measurement of both the total and the functional fraction of ER. The ER status was examined in breast cancer cell lines and in breast cancer biopsy specimens by (i) 3H-E2 binding assay, (ii) immunodetection assays and (iii) by its interaction with 32P-ERE. The sensitive NMBA assay was validated with well-characterized ER(+) breast cancer cell lines and also identified functional variants of ER among breast tumor biopsy specimens.     

Src Drives Growth of Antiestrogen Resistant Breast Cancer Cell Lines and Is a Marker for Reduced Benefit of Tamoxifen Treatment

The underlying mechanisms leading to antiestrogen resistance in estrogen-receptor α (ER)-positive breast cancer is still poorly understood. The aim of this study was therefore to identify biomarkers and novel treatments for antiestrogen resistant breast cancer. We performed a kinase inhibitor screen on antiestrogen responsive T47D breast cancer cells and T47D-derived tamoxifen and fulvestrant resistant cell lines. We found that dasatinib, a broad-spectrum kinase inhibitor, inhibited growth of the antiestrogen resistant cells compared to parental T47D cells. Furthermore western blot analysis showed increased expression and phosphorylation of Src in the resistant cells and that dasatinib inhibited phosphorylation of Src and also signaling via Akt and Erk in all cell lines. Immunoprecipitation revealed Src: ER complexes only in the parental T47D cells. In fulvestrant resistant cells, Src formed complexes with the Human Epidermal growth factor Receptor (HER)1 and HER2. Neither HER receptors nor ER were co-precipitated with Src in the tamoxifen resistant cell lines. Compared to treatment with dasatinib alone, combined treatment with dasatinib and fulvestrant had a stronger inhibitory effect on tamoxifen resistant cell growth, whereas dasatinib in combination with tamoxifen had no additive inhibitory effect on fulvestrant resistant growth. When performing immunohistochemical staining on 268 primary tumors from breast cancer patients who had received tamoxifen as first line endocrine treatment, we found that membrane expression of Src in the tumor cells was significant associated with reduced disease-free and overall survival. In conclusion, Src was identified as target for treatment of antiestrogen resistant T47D breast cancer cells. For tamoxifen resistant T47D cells, combined treatment with dasatinib and fulvestrant was superior to treatment with dasatinib alone. Src located at the membrane has potential as a new biomarker for reduced benefit of tamoxifen.     

乳腺癌免疫组化检测在乳腺癌患者诊治中的意义分析

目的：探讨免疫组化检测在乳腺癌患者诊治中的价值。方法：随机选取2011年1月-2013年1月的68例经过空心穿刺活捡并病理确诊的乳腺癌患者为研究对象,均采用免疫组化检测ER、PR、P53、Bcl-2,全部采用CEF化疗方案治疗3个月后手术治疗,再运用免疫组化SP法检测化疗前后乳腺癌组织中以上指标的阳性表达率情况。结果：ER、PR化疗前后比较无统计学意义（P〉0．05）;而P53、Bcl-2比较有明显的差异性（P〈0．05）;ER、PR的阴性和阳性和疗效情况无明显差异性,而P53、Bcl-2的阴性和阳性表达和化疗的效果有明显的差异性,P〈0．05,具有统计学意义。结论：免疫组化检测中ER、PR对乳腺癌化疗前后无明显差异性,而化疗可通过抑制P53的表达来抑制乳腺癌增值并通过升高Bcl-2表达来调整肿瘤细胞分化。