HER2+ Breast Cancer Therapy: By CPP-ZFN Mediated Targeting of mTOR?

A significant fraction of HER2+ patients develop resistance to available therapies such as trastuzumab. The acquired resistance is primarily due to hyper activation of HER2 downstream PI3K/Akt/mTOR signalling pathway. Hence, identification of inhibitors of components of this pathway, particularly mTOR, is an area of intense investigation. Interestingly, mTOR specific inhibitors (rapamycin/rapalogs) have been tested and shown to potentiate the effect of HER2 inhibitors. However, the use of mTOR inhibitors will also be associated with the limitations inherently linked with extensive use of anticancer drugs e.g., toxicity and acquired drug resistance. Hereby, we hypothesize development of an alternative novel molecular therapeutic intervention based on cell penetrating peptide (CPP), a highly efficient carrier, conjugated to zinc finger nuclease (ZFN), a precise molecular scissor. The use of HER2 specific CPP conjugated to mTOR specific ZFN, will make the mTOR locus non-functional and inhibit the PI3K/Akt/mTOR pathway, essential for growth and proliferation of cancerous cells. With the availability of HER21 cancerous cell specific CPP and proved applications of ZFN in targeted genome engineering of over 11 species, the prospects of success of CPP-ZFN anti-cancer therapy are very high.     

Can Women With HER2-Positive Metastatic Breast Cancer Be Cured?

Breast cancer that is characterized by amplification or over expression of human epidermal growth factor receptor 2 (HER2) accounts for 15% to 20% of all forms of the disease. Although HER2 amplification has been associated with aggressive disease behavior and poor prognosis, the development and availability of a number of HER2-targeted agents has led to improved outcomes for patients with HER2-positive metastatic breast cancer, with data suggesting that overall survival has substantially improved in the past 2 decades. An increasing proportion of HER2-positive metastatic breast cancer is diagnosed as de novo stage IV disease. Patients with de novo metastases are traditionally classified in the general category of metastatic breast cancer and not analyzed as a distinct subgroup, though response to therapy and disease outcomes may differ from that of disease that recurred after early stage disease. Among patients with HER2+ de novo metastatic breast cancer, those who achieve a complete response have a prolonged progression‐free survival and overall survival. Moreover, the fact that some patients achieve a prolonged durable response has raised interest and renewed discussion about whether cure is feasible in the complex context of metastatic breast cancer. In this review, available data associated with the possibility of cure in the population of patients with HER2+ de novo metastatic breast cancer are presented and discussed in detail.     

共表达ER与HER2乳腺癌研究进展

随着肿瘤标志物的广泛应用,目前乳腺癌常根据肿瘤分子特征进行个体化治疗。表达雌激素受体(ER)的乳腺癌对内分泌治疗敏感,但表达人表皮生长因子受体2(HER2)的患者ER表达降低并增加患者对内分泌治疗的抵抗。全文探讨共表达ER和HER2乳腺癌的分子特征、交互应答途径及治疗策略。     

Ligand-Induced Regulation of ERα and ERβ is Indicative of Human Breast Cancer Cell Proliferation

Two estrogen receptors (ER), ER and ER, are expressed in breast cancer but their role in treatment response is unclear. The overall objective of this study was to determine if the presence of ER protein in breast cancer cell lines is an indicator of a poor prognosis based on cell proliferation. In addition, we determined the effect of estradiol (E2) and selective estrogen receptor modulators (SERMs), such as tamoxifen and genistein, on ER and ER protein regulation, to help in the understanding of the mechanism behind their role in modulating cell proliferation. Using western blot and immunofluorescence analysis, the ER positive cell lines, MCF-7 and T47D, were found to contain both ER and ER, and thus were used as model systems. E2 and genistein, which increased cell proliferation in both cell lines, induced an up regulation of ER in both cell lines. This suggests that an estrogenic response in breast cancer cells is indicated by an increase in ER expression. Tamoxifen decreased cell proliferation in both cell lines, while up regulating ER in both cell lines, suggesting that antiestrogenic response is indicated by an increase in ER expression. Although a change in the ER/ER ratio may play a role in the effect seen in cell proliferation, this study indicates that ER is a poor prognosticator of cell proliferation in breast cancer and that ER is a positive prognosticator of responsiveness to antiestrogen treatment.     

Clinical Significance of HER2-Positive and Triple-Negative Status in Small (≤ 1 cm) Node-Negative Breast Cancer

BackgroundData regarding the clinical significance of HER2⁺ and TN status in patients with small node-negative tumors are limited and conflicting. It remains unclear who, among those with small lesions, might benefit from more aggressive adjuvant therapy.Patients and MethodsWe identified all node-negative breast cancer patients with tumor size ≤ 1 cm diagnosed between January 1, 1995 and December 31, 2008 using our institutional breast service database. Patients were classified according to their receptor status into 3 groups: (1) hormone receptor (HR)-positive (estrogen receptor [ER]- or progesterone receptor [PR]-positive, HER2⁻); (2) HER2⁺ (immunohistochemistry 3⁺ or fluorescence in situ hybridization amplification ≥ 2); and (3) TN (ER⁻, PR⁻, and HER2⁻). RFS was calculated using Kaplan-Meier methods.ResultsAmong 656 patients with tumors ≤ 1 cm, 494 (75%) of the patients were HR⁺, 107 (16%) were HER2⁺, and 55 (9%) were TN. Median age was 59 years (range, 27-92 years). Median follow-up was 3.5 years. The 5-year RFS rates were 98.2%, 97.1%, and 83.5% in patients with HR⁺, HER2⁺, and TN tumors, respectively (P < .001). In multivariate analysis, TN status was associated with worse RFS (hazard ratio, 6.70; 95% confidence interval [CI], 3.02-14.86), and HER2⁺ was not (hazard ratio, 1.64; 95% CI, 0.73-3.69).ConclusionTN, but not HER2⁺ status, was associated with worse RFS in patients with T1abN0 tumors, and adjuvant chemotherapy might be considered in patients with TN breast cancer.     

Is Male Breast Cancer Similar or Different than Female Breast Cancer?

OBJECTIVE. To determine if male breast carcinogenesis was similar to its more common female counterpart, we compared incidence patterns among men and women with breast cancer. METHODS. Breast cancer records were obtained from the SEER database. Women were stratified by age < 50 and > or = 50 years to simulate premenopausal and postmenopausal breast cancer. RESULTS. Age-adjusted incidence trends were stable among men but increased among women. Male to female breast cancer ratio was higher for blacks than for whites. Favorable prognostic factors reflective of tumor biology (nuclear grade and hormone receptor expression) were more common for men and postmenopausal women than for premenopausal women. For example, low nuclear grade, estrogen and progesterone receptor-positive expression were more common among men and postmenopausal women than among premenopausal women. The age-specific incidence rate curve for men increased steadily for all ages with a constant slope. On the other hand, age-specific rates for women increased rapidly until age 50 years then rose at a slower rate for postmenopausal women. Age-frequency distribution for male breast cancer was unimodal, with peak incidence at age 71 years. Age-frequency distribution for women was bimodal with early-onset and late-onset incidence at 52 and 71 years, respectively. CONCLUSIONS. Gender-specific incidence trends differed, most likely reflective of female-related changes in surveillance and/or reproductive risk factors. On the other hand, similar prognostic factor profiles reflective of tumor biology, age-specific incidence rate patterns, and age-frequency distributions suggested that male breast cancer was more like postmenopausal than premenopausal female breast cancer.     

Seaweed Prevents Breast Cancer?

To investigate the chemopreventive effects of seaweed on breast cancer, we have been studying the relationship between iodine and breast cancer. We found earlier that the seaweed, wakame , showed a suppressive effect on the proliferation of DMBA (dimethylbenz(a)anthracene)-induced rat mammary tumors, possibly via apoptosis induction. In the present study, powdered mekabu was placed in distilled water, and left to stand for 24 h at 4°C. The filtered supernatant was used as mekabu solution. It showed an extremely strong suppressive effect on rat mammary carcinogenesis when used in daily drinking water, without toxicity. In vitro, mekabu solution strongly induced apoptosis in 3 kinds of human breast cancer cells. These effects were stronger than those of a chemothera-peutic agent widely used to treat human breast cancer. Furthermore, no apoptosis induction was observed in normal human mammary cells. In Japan, mekabu is widely consumed as a safe, inexpensive food. Our results suggest that mekabu has potential for chemoprevention of human breast     

Immunohistochemistry Subtypes (ER/PR/HER) of Breast Cancer: Where Do We Stand in the West of Saudi Arabia?

In Saudi Arabia, cancer of breast is ranked the most frequent neoplasm and second source of cancer deathin the female population. Breast cancer (BC) fast diagnosis, prognosis and medication management necessitate,these days, immunohistochemistry (IHC) assessment of hormone receptors and HER2 expression profile. Thepresent report defines the IHC profile of ER, PR and HER2 in Saudi female breast neoplasms of ductal andlobular types and associations ER, PR and HER2 expression patterns with various clinicopathological factors(age, type of tumor, size, laterality, histological grade, and involvement of axillaries lymph nodes). Ninety ninecases of breast tumors were recruited from the pathology department archive of King Abdulaziz UniversityHospital, Kingdom of Saudi Arabia. ER, PR and HER2 expression was assessed using IHC staining. Ductalcarcinomas with a variety of histological grades constituted 88 (88.8%) of total cases. Seventy four (77.8%), 59(62.1%), and 35 (36.8%) of ductal carcinomas showed positive staining for ER, PR and HER2, in that order.Remaining breast cancer cases were four (4%) lobular carcinomas and two (2%) mixed form of ductal andlobular types, which were ER+, PR+, and HER2-. Breast cancer expression pattern of ER, PR and HER2 inSaudi female is different from that of Tunisian and Jordanian female populations and closer to the expressionpattern of Egyptian, Lebanese, Iraqi and western country females. Furthermore, the present study found twoIHC patterns of breast cancer ER+/PR-/HER2+ (5%) and ER+/PR-/HER2- (11.1%), which had not been reportedin other Arabic studies. Thus the rates of IHC expression patterns in breast cancer show some variation amongArabic female populations.     

HER2-positive Breast Cancer Brain Metastases: Multiple Responses to Systemic Chemotherapy and Trastuzumab—a Case Report

Brain metastases from metastatic breast cancer typically occur in 10–15% of patients and are associated with survival of 3–6 months. Recent series have shown that women with HER2-postive metastatic breast cancer receiving the drug trastuzumab develop brain metastases more frequently than this, but also that continuation of trastuzumab after diagnosis of brain metastases in such patients is associated with extended survival. Authors have speculated that this is due to improved systemic control of disease; however, a possibility is that trastuzumab may have a beneficial effect on cerebral metastases themselves. We report the case of a woman with HER2-positive metastatic breast cancer who developed multiple brain metastases while on trastuzumab, in whom the addition of systemic chemotherapy to continued trastuzumab has produced multiple treatment responses associated with prolonged survival. This is the first report of its kind.     

绝经前ER阳性HER2阴性乳腺癌转移特征分析

目的 分析绝经前雌激素受体(ER)阳性、人类表皮生长因子受体2(HER2)阴性乳腺癌患者复发转移特征.方法 回顾性分析154例ER阳性HER2阴性绝经前复发转移性乳腺癌患者的临床资料,对患者临床及复发转移特征进行总结分析.结果 154例绝经前ER阳性HER2阴性乳腺癌患者,中位发病年龄45岁(26~53岁),中位无病生存时间(DFS)52.4个月(6.1~329.1个月),复发转移多发生在术后2~5年(49.4%,76/154);非内脏转移较内脏转移多发(55.8% vs 44.2%);骨转移最多(52.6%,81/154),内脏转移以肺多见(26.6%,41/154);多因素分析显示,淋巴结转移状态是DFS的主要影响因素(P﹤0.05).结论 绝经前ER阳性HER2阴性乳腺癌患者复发转移多发生在术后2~5年,主要为非内脏转移,骨转移最多;淋巴结转移状态是影响DFS的重要因素.     

Over-expression of EGFR in Breast Cancer

Objective： To explore the relationship of overexpression of epidermal growth factor receptor （EGFR） in occurrence, development and treatment of breast cancer. Methods： Samples of 46 breast adenoma tissues and 86 breast cancer tissues were regularly dehydrate-fixed, embedded in paraffin, sliced in to 5μm thick, stained with SABC immunohistochemistry and coloured with DAB. Results： The positive staining of EGFR was shown as brown- yellow and distributed in cytoplasm. The positive rates in the tissues of breast adenosis and breast cancer were 17.04% （6/46） and 56.98% （49/86） respectively. The positive rates of EGFR in the tissue of invasive ductal carcinoma was 64.49% （41/59）, which was significantly higher than that in in situ carcinoma （P〈0.05）. The positive rate of lymph metastasis group was higher than that in non-lymph metastasis group （P〈0.05）. Conclusion： The overexpression of EGFR was related with occurrence, lymph metastasis and pathologic types of breast cancer. The examination of EGFR in the breast cancer can serve as a guidance for target chemotherapy.     

Preoperative Chemoradiotherapy for Inflammatory Breast Cancer

OBJECTIVE To observe the effect of preoperative chemoradiotherapy for inflammatory breast cancer. METHODS From December 1996 to December 2000, we received and treated 21 patients with inflammatory breast carcinoma with a combined-modality treatment. The chemotherapy protocol consisted of cyclophos-phamide (CTX), pirarubicin (THP-ADM) and 5-fluorouracil (5-FU) or CTX, 5-Fu and methotrexate (MTX). The same infusion scheme was repeated on day 21. After 3-4 cycles the patients were treated with radiotherapy. When the radiation dose reached 40 Gy, the patients who were unable or unwilling to under go an operation received continued radiotherapy. When the radiation dose to the supra clavicular fossa and internal mammary lymph nodes reached 60 Gy and 50 Gy respectively, the radiotherapy was stopped. Chemotherapy was then continued with the original scheme. Patients who had indications for surgery and were willing to under go an operation received no treatment for 2 weeks, after which a total mastectomy was performed. Chemotherapy and radiotherapy was resumed with the original scheme after the operations. When the radiation dose reached 50 Gy, radiotherapy was stopped. RESULTS All patients were followed-up for more than 5 years with a follow-up rate of 100%. The overall 3 and 5-year survival rates of these patients were 42.9%, and 23.8% respectively. For patients in Stage IIIB the 3 and 5-year survival rates were 50.0% and 27.8% respectively, and for patients in Stage IV, the 3 and 5-year survival rates were both 0.0%. There was a significant difference between the 2 stage groups (P<0.05, x2=11.60). For patients who received an operation, the 3 and 5-year survival rates were 80.0% and 33.3% respectively, For patients who were not treated with an operation, the 3 and 5 -year survival rates were both 0.0%, There was a significant difference between the operated and non-operated groups (P<0.05, x2=11.64). CONCLUSION The prognosis of inflammatory breast carcinoma is poor. Before operation, a combined -modality treatment (first chemotherapy, then local therapy, finally chemotherapy and radiotherapy) is the best treatment method.     

Immunohistochemical Detection of Phospho-Akt,Phospho-BAD,HER2 and Oestrogen Receptors α and β in Malaysian Breast Cancer Patients

Activation of Akt signaling pathway has been documented in various human malignancies, including breast carcinoma. The objective of this study is to determine the incidence of Akt phosphorylation in breast tumours and its relationship with expression of ER-α, ER-β, HER2, Ki-67 and phosphorylated Bcl-2 associated death domain (p-BAD). Immunohistochemical staining was performed to detect these molecules on 43 paraffin-embedded breast tumour tissues with commercially available antibodies. Eighteen (41.9%), 3 (7.0%), 23 (53.5%), 35 (81.4%), 21 (48.8%), 29 (67.4%), and 34 (81.0%) of breast tumours were positive for nuclear ER-α, nuclear ER-β, membranous HER2, cytonuclear p-Akt (Thr308), p-Akt (Ser473), p-BAD and Ki-67, respectively. ER-α expression was inversely correlated with HER2 and Ki-67 (P = 0.041 and P = 0.040, respectively). The p-Akt (Ser473) was correlated with increased level of p-BAD (Ser136) (P = 0.012). No relationship of Akt phosphorylation with HER2, ER-α or ER-β was found. The p-Akt (Ser473) immunoreactivity was significantly higher in stage IV than in stage I or II (P = 0.036 or P = 0.009). The higher Ki-67 and lower ER-α expression showed an association with patient age of <50 years (P = 0.004) and with positive nodal status (P = 0.033), respectively. Our data suggest that the Akt phosphorylation and inactivation of its downstream target, BAD may play a role in survival of breast cancer cell. This study does not support the simple model of linear HER2/PI3K/Akt pathway in breast cancer.     

ER阳性HER2阴性复发转移性乳腺癌一线治疗现状

乳腺癌是严重危害女性健康的恶性肿瘤,其发病率高居女性肿瘤疾病首位。其中有70%～80%乳腺癌为雌激素受体（ER）阳性,雌激素的存在可促进乳腺癌细胞的增殖。对于ER阳性复发转移性乳腺癌,化疗、内分泌治疗、分子靶向治疗均占据重要的位置,如何根据不同患者的实际情况,制定个体化、精细化的治疗方案是临床工作中的重要问题。本文就ER阳性HER2阴性复发转移性乳腺癌的一线治疗现状和进展进行总结。     

Changing Natural History of HER2–Positive Breast Cancer Metastatic to the Brain in the Era of New Targeted Therapies

Background

Given the wide adoption of human epidermal growth factor receptor 2 (HER2)-targeted therapies for advanced HER2–positive breast cancer, we studied the natural history of patients with HER2–positive breast cancer brain metastases (BCBM) over time.

Differentially Expressed Proteins in ER+ MCF7 and ER- MDAMB-231 Human Breast Cancer Cells by RhoGDI-α Silencing and Overexpression

Background: The consequence of Rho GDP dissociation inhibitor alpha (RhoGDIα) activity on migration andinvasion of estrogen receptor positive (ER+) and negative (ER-) breast cancer cells has not been studied using theproteomic approach. Changes in expression of RhoGDIα and other proteins interacting directly or indirectly withRhoGDIα in MCF7 and MDA-MB-231, with different metastatic potentials is of particular interest. Materialsand Methods: ER+ MCF7 and ER- MDA-MB-231 cell lines were subjected to two-dimensional electrophoresis(2-DE) and spots of interest were identified by matrix-assisted laser desorption/ionization time of- flight/timeof-flight (MALDI-TOF/TOF) mass spectrometry (MS) analysis after downregulation of RhoGDIα using shortinterfering RNA (siRNA) and upregulated using GFP-tagged ORF clone of RhoGDIα. Results: The resultsshowed a total of 35 proteins that were either up- or down-regulated in these cells. Here we identifed 9 and 15proteins differentially expressed with silencing of RhoGDIα in MCF-7 and the MDA-MB-231 cells, respectively.In addition, 10 proteins were differentially expressed in the upregulation of RhoGDIα in MCF7, while only oneprotein was identified in the upregulation of RhoGDIα in MDA-MB-231. Based on the biological functions of theseproteins, the results revealed that proteins involved in cell migration are more strongly altered with RhoGDI-αactivity. Although several of these proteins have been previously indicated in tumorigenesis and invasiveness ofbreast cancer cells, some ohave not been previously reported to be involved in breast cancer migration. Hence,these proteins may serve as useful candidate biomarkers for tumorigenesis and invasiveness of breast cancercells. Conclusions: Future studies are needed to determine the mechanisms by which these proteins regulate cellmigration. The combination of RhoGDIα with other potential biomarkers may be a more promising approachin the inhibition of breast cancer cell migration.     

ER/PR+和HER2-型乳腺癌患者免疫组化指标的列线图预后模型

目的：探讨改良雌激素受体（estrogen receptor,ER)/孕激素受体(progesterone receptor,PR)阳性（+）及人类表皮生长因子受体2（human epidermal growth factor receptor 2,HER2）阴性（-）（ER/PR+、HER2-）型乳腺癌患者的传统预后模型,满足目前的临床实际需求。方法：选取了2009 年1 月至2009 年12 月上海市黄浦区中心医院乳腺外科收治的335 例ER/PR+、HER2-型乳腺癌患者。将97 个变量纳入模型,采用SCAD变量选择的方法,在充分考虑协变量是否存在对数线性关系、非对数线性关系（分段线性关系）临界值的合理确定、共线问题后,构建一个新的ER/PR+、HER2-型乳腺癌患者传统免疫组化指标的Cox回归预后模型,并进一步建立其列线图模型;在此基础上建立了术后1、3 和5 年生存概率的列线图;并通过比较模型的区分度（discrimination）和校准度（calibration）来评价模型的预测能力。结果：通过乳腺癌预后建立Cox 回归模型结果显示,患者的预后与组织级别、淋巴结转移、Ki67、PR和年龄等因素有关;其中组织级别和淋巴结转移对风险比的影响呈对数线性关系,Ki67、PR和年龄对风险比的影响呈非对数线性关系,其合理临界值分别为Ki67（60%）、PR（20%）和年龄（55 岁）。该模型术后1、3 和5 年的ROC曲线下面积（AUC值）均高于0.85,说明该Cox 回归模型具有较高的区分度。该模型Gr?nnesby-Borgan 拟合优度检验统计量值为1.37、对应的P值为0.5,说明该Cox回归模型有较好的校准度。结论：通过改良ER/PR+和HER2-型乳腺癌患者的传统预后模型,建立患者术后1、3 和5年生存概率的列线图,能准确、直观、有效地预测患者的生存概率,对乳腺癌患者临床治疗有较好的指导意义。