Prognosis Of HER2-positive Breast Cancer Research Articles

Abstract P5-04-26: Expression of cytotoxic T lymphocyte antigen-4 (CTLA-4) is associated with tumor-infiltrating lymphocytes (TILs) levelin HER2-positive breast cancers

Abstract Though CTLA4 expression was reported in various tumor types, expression of CTLA4 is not well known in breast cancers, especially HER2-positive breast cancers. TILs level has significant role in treatment response and prognosis in HER2-positive breast cancers. Total 167 patients with HER2-positive breast cancers were included. All patients were pre-operatively chemotherapy and radiotherapy naïve. All received adjuvant standard treatment. Histologic TILs evaluation was performed with full face hematoxylin and eosin sections. Immunohistochemistry for CTLA4 was performed with tissue microarray sections. CTLA4 expression was evaluated separately for tumor cells and TILs. Cytoplasmic and/or membranous stains were assessed and human appendix was used as positive control. The intensity and percentage of positivity were evaluated collectively. Immunostaining score was calculated by multiplying percentage of positive cells by staining intensity. Total immunostaining score was obtained by adding tumor cells score and TILs score. Expression level was divided into two categories (low and high) according to mean value. Only 11 patients (6.6%), 47 patients (28.1), and 10 patients (6.0) showed total negative staining for CTLA4 on tumor cells, TILs and both on tumor cells and TILs, respectively. According to mean score on tumor cells, 97 (58.1%) patients showed low level of CTLA4 expression and 70 (41.9%) showed high level of CTLA4 expression. One hundred and two (61.1%) patients had low expression and 65 (38.9%) patients had high expression of CTLA4 on TILs based on the mean value of score of TILs. According to mean value of total score both on tumor cells and TILs, 70 patients (41.9%) were categorized as high expression and 97 patients (58.1%) were categorized as low CTLA4 expression. TILs level, CTLA4 immunostaining score on tumor cells, CTLA4 immunostaining score on TILs, and total CTLA4 immunostaining score on tumor cells and TILs were significantly correlated each other. High expression level of CTLA4 on tumor cells was significantly associated with negative expression of hormone receptor and high TILs level. Also, high CTLA4 expression on TILs significantly correlated with high histologic grade, negative expression of hormone receptor and high TILs level. High level of total CTLA4 expression both on tumor cells and TILs was significantly correlated with negative expression of hormone receptor and high TILs level. However, expression level of CTLA4 was not associated with overall survival and disease-free survival. In conclusions, CTLA4 expression was common in HER2-positive breast cancers and the level of CTLA4 expression was associated with hormone receptor negativity and TILs level in HER2-positive breast cancers. Table 1. Correlation of TILs level, CTLA4 immunostaining score on tumor cells, TILs, and total immunostaining scoreimmunostaining score on tumor cellsimmunostaining score on TILsTotal immunostaining score on tumor cells and TILsTILs level0.254 (<0.001)0.394 (<0.001)0.312 (<0.001)Immunostaining score of CTLA-4 in tumor cells0.565 (<0.001)0.815 (<0.001)Immunostaining score of CTLA-4 in TILs0.783 (<0.001) Table 2. Correlation between CTLA-4 expression and clinicopathologic factorsLowHighLowHighLowHighHistologic grade1.0000.0390.754Low (grade 1, 2)51 (52.6)36 (51.4)60 (58.8)27 (41.5)52 (53.6)35 (50.0)High (grade 3)46 (47.4)34 (48.6)42 (41.2)38 (58.5)45 (46.4)35 (50.0)Necrosis0.3251.0000.325Absent30 (30.9)27 (38.6)35 (34.3)22 (33.8)30 (30.9)27 (38.6)Present67 (69.1)43 (61.4)67 (65.7)43 (66.2)67 (69.1)43 (61.4)Lymphovascular invasion0.7540.2650.754Absent51 (52.6)39 (55.7)51 (50.0)39 (60.0)51 (52.6)39 (55.7)Present46 (47.4)31 (44.3)51 (50.0)26 (40.0)46 (47.4)31 (44.3)Hormone receptor expression0.0120.0400.005Negative37 (38.1)41 (58.6)41 (40.2)37 (56.9)36 (37.1)42 (60.0)Positive60 (61.9)29 (41.4)61 (59.8)28 (43.1)61 (62.9)28 (40.0)TILs level0.001<0.001<0.001≤10%42 (43.3)19 (27.1)50 (49.0)11 (16.9)44 (45.4)17 (24.3)20-60%45 (46.4)29 (41.4)43 (42.2)31 (47.7)43 (44.3)31 (44.3)>60%10 (10.3)22 (31.4)9 (8.8)23 (35.4)10 (10.3)22 (31.4) Citation Format: Ahrong Kim, Jee Yeon Kim, So Jeong Lee. Expression of cytotoxic T lymphocyte antigen-4 (CTLA-4) is associated with tumor-infiltrating lymphocytes (TILs) levelin HER2-positive breast cancers [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-04-26.

197P - The efficacy of preoperative breast cancer chemotherapy without anti-HER2-targeted treatment: Single center experience in setting of no reimbursement in Poland (2011-2015)

BackgroundTargeted anti-HER2 therapy is a keystone in radical breast cancer therapy. In Poland preoperative use of trastuzumab was not reimbursed until 2016 and pertuzumab is still not covered. Moreover, adjuvant use of trastuzumab was not covered for patients with stage IIIB-C breast cancer. The aim of the study was to analyse of the subset of patients with HER2-positive breast cancer who were treated preoperatively in s center in Poland without use of anti-HER2 medications to analyse their prognosis compared to other breast cancer subtypes. MethodsWe reviewed the records of patients enrolled to the prospective study of prediction of chemotherapy response (MILESTONE-BreastPred). All patients were enrolled between 2011—2015, with intent of preoperative breast cancer chemotherapy, mainly by AC-P or TAC regimens. In the whole group PET/CT was used as an method of staging. ResultsTable197PTableSubtypeHER2-positiveTNBCLUM B HER2-negativePnumer of patients11987160median age4742.746.6n.s.% G366.486.147.40.001% N+74.860.967.5n.s.% CSIII56.242.938.80.048% de novo CSIV11.93.58.1n.s.% inoperable after chemotherapy [%]17.710.310n.s.% pCR32.6539.7420.140.005% 5-year PFS47.270.668.30.001median PFS [mo]56.7NR92.90.001 ConclusionsHER2-positive breast cancer in Polish population is at presentation more advanced than other subtypes, and despite relatively high pCR rate, has poor prognosis, when treated without sufficient anti-HER2 therapy. Prognosis in HER2-positive breast cancer in the analysed subgroup of Polish patients was poorer than in TNBC. The results underline the importance of treatment according to international guidelines and speak in favour of including anti-HER2 therapy preoperatively. The study was supported by the Polish National Center of Research and Development MILESTONE project – Molecular diagnostics and imaging in individualized therapy for breast, thyroid and prostate cancer, grant no. STRATEGMED 2/267398/4/NCBR/2015. Legal entity responsible for the studyThe authors. Fundingthe Polish National Center of Research and Development MILESTONE project – Molecular diagnostics and imaging in individualized therapy for breast, thyroid and prostate cancer, grant no. STRATEGMED 2/267398/4/NCBR/2015. DisclosureAll authors have declared no conflicts of interest.

High expression of the vacuole membrane protein 1 (VMP1) is a potential marker of poor prognosis in HER2 positive breast cancer.

BackgroundFusion genes result from genomic structural changes, which can lead to alterations in gene expression that supports tumor development. The aim of the study was to use fusion genes as a tool to identify new breast cancer (BC) genes with a role in BC progression.MethodsFusion genes from breast tumors and BC cell lines were collected from publications. RNA-Seq data from tumors and cell lines were retrieved from databanks and analyzed for fusions with SOAPfuse or the analysis was purchased. Fusion genes identified in both tumors (n = 1724) and cell lines (n = 45) were confirmed by qRT-PCR and sequencing. Their individual genes were ranked by selection criteria that included correlation of their mRNA level with copy number. The expression of the top ranked gene was measured by qRT-PCR in normal tissue and in breast tumors from an exploratory cohort (n = 141) and a validation cohort (n = 277). Expression levels were correlated with clinical and pathological factors as well as the patients’ survival. The results were followed up in BC cohorts from TCGA (n = 818) and METABRIC (n = 2509).ResultsVacuole membrane protein 1 (VMP1) was the most promising candidate based on specific selection criteria. Its expression was higher in breast tumor tissue than normal tissue (p = 1x10-4), and its expression was significantly higher in HER2 positive than HER2 negative breast tumors in all four cohorts analyzed. High expression of VMP1 associated with breast cancer specific survival (BCSS) in cohort 1 (hazard ratio (HR) = 2.31, CI 1.27–4.18) and METABRIC (HR = 1.26, CI 1.02–1.57), and also after adjusting for HER2 expression in cohort 1 (HR = 2.03, CI 1.10–3.72). BCSS was not significant in cohort 2 or TCGA cohort, which may be due to differences in treatment regimens.ConclusionsThe results suggest that high VMP1 expression is a potential marker of poor prognosis in HER2 positive BC. Further studies are needed to elucidate how VMP1 could affect pathways supportive of tumorigenesis.

Abstract P1-05-02: Novel mechanisms of Rac1 activation by the Cullin-3/KCTD10 ubiquitin E3 complex in HER2-positive breast cancer

Abstract Overexpression of HER2 in breast cancer is correlated with poor prognosis. HER2-targeted drugs, such as trastuzumab and lapatinib, have been successful to treat HER2-positive breast cancers, however, the acquisition of the drug resistance of the cells is recognized. Here we suggest the novel molecular targets to cure HER2-positive breast cancers. The oncogenic roles of Rac1, a Rho family small GTPase, in a variety of cancers have been demonstrated. For example, the elevated expression or hyperactivation of Rac1 is frequently observed in human cancers, correlating with their aggressiveness and poor prognosis. In breast cancers, upregulation of Rac1 GEF (GTP exchange factor) and downregulation of Rac1 GAP (GTPase activating protein) have been reported. Moreover, activation of Rac1 contributed to trastuzumab resistance, which poses a serious problem during chemotherapy. In the present study, we first investigated in detail in which subtypes of breast cancers mRNA expression of Rac1 is correlated with their poor prognosis. Using the METABRIC database, we found that high mRNA expression of Rac1 significantly correlated with the poor prognosis of HER2-positive breast cancer (p=0.0012, High: n=49, Low: n=171). On the other hands, other three types (basal, claudin-low, or luminal-B type) did not show significant correlation between the expression levels of Rac1 mRNA and their prognosis (p=0.15, High: n=97, Low: n=102; p=0.052, High: n=110, Low: n=89; p=0.17, High: n=70, Low: n=391; respectively). In luminal-A type breast cancer, low mRNA expression of Rac1 significantly correlated with poor prognosis (p=0.0046, High: n=492, Low: n=187). We next investigated the molecular mechanism underlying Rac1 activation in HER2-positive breast cancer cells, SKBR-3 cells. We found that Cullin-3 (CUL3, a subunit of a RING ubiquitin E3 ligase complex) and its adaptor protein KCTD10 are essential for Rac1 activation. Mechanistically, CUL3/KCTD10 ubiquitinate RhoB, a Rho family small GTPase that suppresses the activation of Rac1, leading to the degradation RhoB. We also found that HER2 signaling is essential for the activation of Rac1. Conclusions: This study reveals that the novel molecular axis CUL3/KCTD10/RhoB regulates the Rac1 activation in HER2-positive breast cancer cells. The interference of CUL3/KCTD10 complex formation may be a new strategy to the treatment of HER2- and Rac1-positive breast cancers. Citation Format: Murakami A, Maekawa M, Kusakabe E, Yamasawa H, Aoki R, Komatsu S, Taguchi K, Nishiyama K, Yamashita M, Sugimori W, Kawai K, Nakayama J, Araki N, Semba K, Taguchi T, Kamei Y, Takada Y, Higashiyama S. Novel mechanisms of Rac1 activation by the Cullin-3/KCTD10 ubiquitin E3 complex in HER2-positive breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-05-02.

Evaluation of the Predictive and Prognostic Values of Stromal Tumor-Infiltrating Lymphocytes in HER2-Positive Breast Cancers treated with neoadjuvant chemotherapy.

BackgroundStromal tumor-infiltrating lymphocytes (sTILs) have been identified as a predictive biomarker for response to neoadjuvant chemotherapy (NAC) and prognosis in human epidermal growth factor receptor 2 (HER2)-positive breast cancers. However, standardized scoring methods for use in clinical practice need to be established, and the optimal threshold of sTILs to predict pathological complete response (pCR) and prognosis in HER2+ breast cancers has not yet been defined.ObjectiveThe predictive and prognostic values of sTILs in patients with HER2-positive breast cancer treated with NAC were evaluated, with the aim to explore the optimal thresholds of sTILs and to investigate the feasibility of scoring methods in clinical practice.Patients and MethodsA total of 143 core needle biopsy specimens of HER2-positive invasive breast cancers obtained from Chinese patients who had been treated with trastuzumab-based NAC followed by surgery between 2009 and 2015 were extracted from the pathology database of Fudan University Shanghai Cancer Center. sTIL levels in the pre-NAC core needle biopsy specimens were scored using methods recommended by the International TILs Working Group 2014. The associations between sTILs and pCR, disease-free survival (DFS), and overall survival (OS) were evaluated, and the optimal thresholds for predictive and prognostic values of sTILs were analyzed.ResultsFirst, sTILs were associated with a higher pCR rate in HER2-positive breast cancers. Univariate (per 10% sTILs: odds ratio [OR] 1.05, 95% confidence interval [CI] 1.02–1.08, p = 0.001) and multivariate regression analyses (per 10% sTILs: OR 1.04, 95% CI 1.00–1.07, p = 0.034) indicated that sTILs as a continuous variable were a significant predictor of pCR in HER2-positive breast cancers. Receiver operating characteristics (ROC) curve analysis showed that a 20% threshold best distinguished the pCR subgroup from the non-pCR subgroup. The dichotomized sTILs with a threshold set at 20% was a strong predictor of pCR in the univariate (OR 0.25, 95% CI 0.12–0.52, p < 0.001) and multivariate analyses (OR 0.35, 95% CI 0.14–0.87, p = 0.024). Second, sTILs were associated with better prognosis in HER2-positive breast cancers. Univariate (DFS: hazard ratio [HR] 0.91, 95% CI 0.88–0.95, p < 0.001; OS: HR 0.88, 95% CI 0.83–0.94, p < 0.001), and multivariate analyses (DFS: HR 0.93, 95% CI 0.90–0.97, p < 0.001; OS: HR 0.92, 95% CI 0.86–0.98, p = 0.009) suggested that sTILs as a continuous variable had a strong predictive value for improved DFS and OS. As a binary variable with a threshold of 20%, univariate (DFS: HR 6.60, 95% CI 2.91–14.95, p < 0.001; OS: HR 10.29, 95% CI 2.37–44.66, p = 0.002) and multivariate analyses (DFS: HR 3.87, 95% CI 1.65–9.12, p = 0.002; OS: HR 4.74, 95% CI 1.02–22.01, p = 0.047) indicated that patients with ≥ 20% sTILs had a significantly better prognosis than the patients with < 20% sTILs.ConclusionsOur study indicates that baseline sTILs scored by methods recommended by the International TILs Working Group in pre-NAC core needle biopsy specimens are significantly correlated with pCR and prognosis in HER2-positive breast cancers. A 20% threshold for sTILs may be a feasible diagnostic marker to predict pCR to NAC and prognosis in patients with HER2-positive breast cancers.

Phosphorylated HER3 and FITC-labeled trastuzumab immunohistochemistry in patients with HER2-positive breast cancer treated with adjuvant trastuzumab.

The development of trastuzumab has significantly improved the prognosis of HER2-positive breast cancer. However, disease recurs in some patients with HER2-positive breast cancer. A new strategy for treating HER2-positive breast cancer is necessary. Although several studies have reported that HER3 is a prognostic factor for HER2-positive breast cancers, phosphorylated HER3 (pHER3) has not been well studied. There has been no survival analysis including immunohistochemistry with trastuzumab as the primary antibody. We analyzed immunohistochemistry using anti-pHER3 antibody and FITC-labeled trastuzumab (FITC-tra). Of 78 patients enrolled in the study, we could evaluate the immunohistochemistry for pHER3 in 71 cases and that for FITC-tra in 72 cases. Sixteen cases were positive for pHER3 (16/71, 22.5%), and 19 positive for FITC-tra (19/72, 26.4%). Kaplan-Meier analysis showed a significant association of pHER3 positivity (p = 0.011) but not HER3 positivity or FITC-tra positivity with disease-free survival. Therefore, immunohistochemical evaluation of pHER3 in HER2-positive breast cancer may provide a useful biomarker. An expanded study of pHER3 involving standardization of the pHER3 test to be encouraged.

Abstract B169: Neratinib has clinical activity in HER2-amplified breast cancer patients with tumors that have acquired activating mutations in HER2

Abstract Overexpression/amplification of HER2/ERBB2 occurs in 20% of breast cancers. Thanks to specific anti-HER2 agents, the prognosis of HER2-positive breast cancer has improved considerably. However, acquired resistance inevitably emerges over time and tumors escape pharmacologic pressure. In this work, we propose that acquisition of activating somatic mutations in HER2 upon anti-HER2 therapy may be more frequent than commonly reported and can reduce sensitivity to these agents. Moreover, we tested whether neratinib, an irreversible pan-HER inhibitor, is effective in tumors bearing both amplification and mutations of ERBB2. By targeted exome sequencing, we found that samples from metastatic breast cancer (MBC) patients relapsing to multiple lines of anti-HER2 therapy presented the acquisition of HER2 mutations. These mutations spanned from the extracellular domain (L313I, R456C) to the kinase domain (L755S, D769Y) of the receptor. To investigate the role of these mutations in drug resistance, we conducted functional studies by stably transducing the L755S HER2 mutation (the most frequent HER2 mutation in breast cancer) in two ERBB2-amplified breast cancer cell lines intrinsically sensitive to HER2 inhibition. In both models, we found that expression of L755S mutant-HER2 was sufficient to limit sensitivity to trastuzumab, lapatinib, or the combination of both agents. Consistently, neither trastuzumab nor lapatinib was effective in inhibiting tumor growth of patient-derived xenografts established from a patient with ERBB2-amplified/mutant (D769Y) breast cancer. However, neratinib treatment demonstrated marked sensitivity in this tumor model, resulting in significant tumor growth inhibition. The antitumor activity of neratinib was also explored in breast cancer patients with coexisting ERBB2 amplification and mutation, either by compassionate use after failure of standard-of-care therapy or as part of a “basket” trial (NCT01953926) enrolling ERBB2-mutant patients. In both settings, we observed durable clinical response to neratinib. MBC case #HER2 co-mutationResponse to neratinibDurability of response (mo)1D769YSD62L313ISD93Y772_A775dupSD44L755SSD55V777LPR6 Our findings indicate that acquired HER2 mutations may reduce the effectiveness of therapeutic agents commonly used for the management of ERBB2-amplified MBC. Moreover, we propose neratinib as an effective treatment option for patients whose tumors harbor both ERBB2 amplifications and mutations. Citation Format: Emiliano Cocco, F. Javier Carmona, Helen H. Won, Michael F. Berger, David M. Hyman, Valentina Rossi, Carmen Chan, Alyssa Moriarty, Kyriakos P. Papadopoulos, Michael J. Wick, James Cownie, Ivana Sarotto, Richard E. Cutler, Francesca Avogadri-Connors, Peter Savas, Alshad S. Lalani, Valentina Boni, Sherene Loi, Jose Baselga, Filippo Montemurro, Maurizio Scaltriti. Neratinib has clinical activity in HER2-amplified breast cancer patients with tumors that have acquired activating mutations in HER2 [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr B169.

Trastuzumab and survival of patients with metastatic breast cancer.

Prognosis of Her2-positive breast cancer has changed since the introduction of trastuzumab for treatment in metastatic and early breast cancer. It was described to be even better compared to prognosis of Her2-negative metastatic breast cancer. The purpose of this study was to evaluate the effect of trastuzumab in our cohort. Besides the effect of adjuvant pretreatment with trastuzumab on survival of patients with metastatic Her2-positive breast cancer was analyzed. All patients with primary breast cancer of the Regional Breast Cancer Center Dresden diagnosed during the years 2001-2013 were analyzed for treatment with or without trastuzumab in the adjuvant and in the metastatic treatment setting using Kaplan-Meier survival estimation and Cox regression. Age and tumor stage at time of first diagnosis of breast cancer as well as hormone receptor status, grading, time, and site of metastasis at first diagnosis of distant metastatic disease were analyzed. Of 4.481 female patients with primary breast cancer, 643 presented with metastatic disease. Her2-positive status was documented in 465 patients, including 116 patients with primary or secondary metastases. Median survival of patients with Her2-positive primary metastatic disease was 3.0years (95% CI 2.3-4.0). After adjustment for other factors, survival was better in patients with Her2-positive breast cancer with trastuzumab therapy compared to Her2-negative metastatic disease (HR 2.10; 95% CI 1.58-2.79). Analysis of influence of adjuvant therapy with and without trastuzumab by Kaplan-Meier showed a trend for better survival in not pretreated patients. Median survival was highest in hormone receptor-positive Her2-positive (triple-positive) primary metastatic breast cancer patients with 3.3years (95% CI 2.3-4.6). Prognosis of patients with Her2-positive metastatic breast cancer after trastuzumab treatment is more favorable than for Her2-negative breast cancer. The role of adjuvant chemotherapy with or without trastuzumab warrants further research. Survival is best in triple-positive metastatic breast cancer. This will effect counseling at the time of first diagnosis of metastatic breast cancer.

High expression of PLA2G16 is associated with a better prognosis in HER2-positive breast cancer.

PLA2G16 functions as a phosphatase in metabolism and its abnormal expression is closely associated with tumor progression. The aim of this study is to investigate the prognosis value of PLA2G16 in breast cancer. A tissue microarray including 200 invasive ductal carcinoma specimens was constructed. Immunohistochemistry was performed to determine the PLA2G16 expression status. The Kaplan-Meier analysis and log-rank test were used to evaluate the prognostic value of PLA2G16. The Multivariate Cox regression analysis was performed to identify whether PLA2G16 was an independent prognostic factor. In our retrospective study, Kaplan-Meier analysis showed that elevated PLA2G16 expression was correlated with improved DFS (P=0.032) in the whole breast cancer patients. In further subgroup analysis, PLA2G16 overexpression was found to be associated with prolonged DFS (P=0.018) in HER2-positive breast cancer patients. More importantly, Multivariate analysis suggested that PLA2G16 was a significant independent prognostic factor in HER2-enriched patients [hazard ratio (HR) =0.151; 95% confidence interval (CI) =0.034-0.672; P=0.013]. Our study evaluated the prognostic significance of PLA2G16 in patients with HER2-positive breast cancer and confirmed the relevance of this metabolism-related gene in patient outcome.

The coexpression of EphB4 and EphrinB2 is associated with poor prognosis in HER2-positive breast cancer.

ObjectiveHER2 overexpression is associated with aggressive phenotypes in breast cancer, including increased tumor proliferation, greater invasiveness, and reduced overall survival. The overall response rate to HER2-targeted therapies remains <30%. There is an urgent need for the identification of efficient markers to predict patients with a poor prognosis. This study was designed to investigate the correlation between EphB4 and EphrinB2 expression and the clinicopathological characteristics of HER2-positive breast cancer.Materials and methodsA total of 111 primary HER2-positive breast cancer patients were enrolled in this study (diagnosed since December 2005 to November 2010 from the Second Hospital of Dalian Medical University). The protein expression of EphB4 and EphrinB2 was examined by immunohistochemistry using paraffin-embedded tumor tissues.ResultsThere was a significant correlation between EphB4 and EphrinB2 expression (P=0.013, r=0.255). Kaplan–Meier analysis showed that the prognosis of patients with a high expression of both EphB4 and EphrinB2 was significantly worse than the prognosis of patients with either EphB4 or EphrinB2 expression and patients with negative expression (hazard ratio [HR] =1.935, P=0.0224). However, high expression of EphB4 or EphrinB2 alone was not an independent prognostic factor to predict worse overall survival. To summarize, HER2-positive breast cancer patients with overexpression of both EphB4 and EphrinB2 were associated with the worst prognosis.ConclusionHigh expression of EphB4 and EphrinB2 correlated with poor overall survival, which can serve as an independent prognostic indicator in primary HER2-positive breast cancer patients.

Decreased expression of stomatin predicts poor prognosis in HER2-positive breast cancer.

BackgroundHuman epidermal growth factor receptor-2 (HER2) is a transmembrane tyrosine kinase receptor that is overexpressed in 25 to 30 % of human breast cancers and is preferentially localized in lipid rafts. Stomatin is a membrane protein that is absent from the erythrocyte plasma membrane in patients with congenital stomatocytosis and is the major component of the lipid raft.ResultsIn a total of 68 clinical cases of HER2-positive breast cancer, the absence of stomatin expression was associated with a decreased 5-year survival (65 % vs. 93 %, p = 0.005) by survival analysis. For stage I-III HER2-positive breast cancer, the absence of stomatin expression was associated with a decreased 5-year disease-free survival (57 % vs. 81 %, p = 0.016) and was an independent prognostic factor by multivariate analysis. Negative stomatin expression predicts distant metastases in a hazard ratio of 4.0 (95 % confidence interval from 1.3 to 12.5).ConclusionsThese results may suggest that stomatin is a new prognostic indicator for HER2-positive breast cancer.

Gasdermin B expression predicts poor clinical outcome in HER2-positive breast cancer.

Around, 30–40% of HER2-positive breast cancers do not show substantial clinical benefit from the targeted therapy and, thus, the mechanisms underlying resistance remain partially unknown. Interestingly, ERBB2 is frequently co-amplified and co-expressed with neighbour genes that may play a relevant role in this cancer subtype. Here, using an in silico analysis of data from 2,096 breast tumours, we reveal a significant correlation between Gasdermin B (GSDMB) gene (located 175 kilo bases distal from ERBB2) expression and the pathological and clinical parameters of poor prognosis in HER2-positive breast cancer. Next, the analysis of three independent cohorts (totalizing 286 tumours) showed that approximately 65% of the HER2-positive cases have GSDMB gene amplification and protein over-expression. Moreover, GSDMB expression was also linked to poor therapeutic responses in terms of lower relapse free survival and pathologic complete response as well as positive lymph node status and the development of distant metastasis under neoadjuvant and adjuvant treatment settings, respectively. Importantly, GSDMB expression promotes survival to trastuzumab in different HER2-positive breast carcinoma cells, and is associated with trastuzumab resistance phenotype in vivo in Patient Derived Xenografts. In summary, our data identifies the ERBB2 co-amplified and co-expressed gene GSDMB as a critical determinant of poor prognosis and therapeutic response in HER2-positive breast cancer.

Twenty years of anti-HER2 therapy-associated cardiotoxicity

Over the past 20 years, the prognosis of HER2-positive breast cancer has been transformed by the development of anti-HER2 targeted therapies. In early clinical trials of trastuzumab (ie, the first anti-HER2 agent to be developed) cardiotoxicity became a major concern. In the first published phase 3 trial of trastuzumab, 27% of patients receiving anthracyclines and trastuzumab experienced cardiac events and 16% suffered from severe congestive heart failure. In subsequent trials conducted in advanced and early settings, the incidence of cardiac events was reduced through changes in chemotherapy regimens, more strict patient selection and close cardiac assessment. However, cardiotoxicity remains a significant problem in clinical practice that is likely to increase as new agents are approved and exposure times increase through improved patients' survival. Though numerous trials have led to improved understanding of many aspects of anti-HER2 therapy-related cardiotoxicity, its underlying physiopathology mechanisms are not well understood. The purpose of this article is to provide an in-depth review on anti-HER2 therapy-related cardiotoxicity, including data on both trastuzumab and the recently developed anti-HER2 targeted agents.

Values of tumor-infiltrating lymphocytes (TILs), CD8+ TILs, and PDL-1 for predicting pathological complete response and prognosis in HER2-positive breast cancer receiving neoadjuvant chemotherapy with trastuzumab.

589Background: The predictive and prognostic values of tumor-infiltrating lymphocytes(TILs) in neoadjuvant chemotherapy have also been demonstrated in triple negative as well as HER2-positive breast cancer (BC). In the present study, we investigated the relationship between the expression and degree of stromal (str)-TILs, CD8+ TILs, and PDL-1 positive cancer cells, and evaluated the values of these 3 factors for predicting pCR and prognosis in HER2-positive BC patients receiving neoadjuvant chemotherapy with trastuzumab. Methods: A total of 128 Japanese HER2-positive BC received taxanes followed by FEC, with the concomitant administration of trastuzumab. The grades of str-TILs were evaluated using the criteria of the International Working Group for TILs in BC, with a high grade being defined as > 40%. Immunohistochemically, positive cancer cells for PDL-1 was defined as > 1%, and high CD8+ was defined as the number of CD8+ TILs > 25 / 1 high power field. The relationship between the expression and degree ...

A Her2-let-7-β2-AR circuit affects prognosis in patients with Her2-positive breast cancer.

BackgroundOur previous studies show that β2-adrenergic receptor (β2-AR) is highly expressed in most Her2-overexpressing breast cancers. However, the mechanisms underlying upregulation of the β2-AR expression in Her2-overexpressing breast cancer cells are not fully understood. The clinical significance of the β2-AR overexpression in breast cancer is unclear.MethodsHuman breast cancer cells MCF-7 and MCF-7/Her2 were transfected with the let-7 mimics or inhibitors. The expression of β2-AR was analyzed by Western blot. The β2-AR status in primary and metastatic sites of breast cancer and the human breast cancer tissue microarrays containing 49 primary tumors and 50 metastatic lymph node tissues was analyzed by immunohistochemistry. The correlation of lymph node metastasis with the β2-AR level was determined in 59 primary tumor tissues from the patients with Her2-positive breast cancer. The clinical prognostic significance of the β2-AR overexpression in the patients with Her2-positive breast cancers was evaluated by a retrospective study.ResultsThe let-7f level in Her2-overexpressing breast cancer cells SKBR3 and BT474 was significantly lower than that in MCF-7 cells, which express low level of Her2. Ectopic expression of Her2 in MCF-7 cells (MCF-7/Her2) represses the expression of microRNA let-7f, which is previously identified to regulate baseline β2-AR expression. The treatment with MEK1/2 inhibitors PD98059 or PD184352 effectively restored the let-7f level, suggesting that Her2-overexpression-mediated ERK constitutive activation inhibited let-7f, leading to the upregulation of the β2-AR expression. The transfection with the let-7f mimics markedly downregulated the β2-AR level, whereas the let-7 inhibitor significantly upregulated the β2-AR expression in both parental MCF-7 and MCF-7/Her2 cells. In addition, treatment of MCF-7/Her2 cells with isoproterenol resulted in a concentration-dependent reduction of the let-7f expression, demonstrating that the inhibitory effect of Her2 overexpression on let-7f can be reinforced by agonist-triggered β2-AR activation. We further demonstrate that high level of β2-AR associates with lymph node metastasis and poor outcome in the patients with Her2-positive breast cancer.ConclusionsThe mutual and reciprocal interaction between Her2, β2-AR, and let-7f may maintain a high level of β2-AR in breast cancer cells. Our data suggest that β2-AR may be a new useful biomarker for predicting prognosis in Her2-positive breast cancer and may also be a promising selective therapeutic target for the aggressive subtype of breast cancer.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-015-1869-6) contains supplementary material, which is available to authorized users.

Adjuvant regimens with trastuzumab administered for small HER2-positive breast cancer in routine clinical practice.

Trastuzumab has proven to improve the prognosis of HER2-positive breast cancer, but the information available about its administration for small tumors is still limited. Therefore, we assessed the use of adjuvant regimens with trastuzumab for the treatment of small HER2-positive breast cancer in routine clinical practice. This observational study was conducted in patients with HER2-positive breast adenocarcinoma ≤1.5cm who received trastuzumab-based adjuvant treatment in clinical practice. Clinical/histopathological data were retrieved from patients' medical charts. A total of 101 evaluable patients were enrolled (median age [range], 56.7 [49.0-64.8] years; ECOG 0, 98.0%; ductal carcinoma, 88.1%; lymph nodes N0, 79.2%). Only five (5.0%) patients received neoadjuvant treatment, while all patients underwent tumor surgery. Adjuvant trastuzumab was administered at a mean (±SD) dose of 5.9±1.5mg/kg/cycle, and mostly in a three-weekly schedule (89 [89.0%] patients). The most frequent adjuvant therapy used with trastuzumab was chemotherapy (87 [86.1%] patients), followed by radiotherapy (63 [62.4%] patients) and hormone therapy (52 [51.5%] patients). Chemotherapy regimens mainly included doxorubicin, cyclophosphamide and paclitaxel/docetaxel (n=30), docetaxel and cyclophosphamide (n=15), docetaxel and carboplatin (n=13). Hormone therapy mainly included letrozole (n=17) and tamoxifen (n=17). Nine (8.9%) patients reported trastuzumab-related adverse events; only one allergic reaction reached grade 3 toxicity. This study shows that trastuzumab-based adjuvant treatment of small HER2-positive breast cancer is mostly based on chemotherapy-mainly paclitaxel/docetaxel. Adjuvant administration of trastuzumab for small HER2-positive breast cancer seems to be similar to that used for larger tumors.

Targeting HER family in HER2-positive metastatic breast cancer: potential biomarkers and novel targeted therapies.

HER2-targeted therapies have radically changed the prognosis of HER2-positive breast cancer over the last few years. However, resistance to these therapies has been a constant, leading to treatment-failure and new tumor progression. Recently, the kinase-impaired HER3 emerged as a pivotal player in oncogenic signaling, with an important role in both non-treated progression and treatment response. HER2/HER3 dimerization is required for full signaling potential and constitutes the key oncogenic unit. Also, when inhibiting PI3K/AKT pathway (as with anti-HER2 drugs) feedback mechanisms lead to a rebound in HER3 activity, which is one of the main roads to resistance. As current strategies to treat HER2-positive breast cancer are unable to inhibit this feedback response, two great promises emerged: the combination of targeted-therapies and drugs targeting HER3. In this article HER2 and HER3-targeted drugs and possible combinations between them, as well as the biomarkers to predict and monitor these drugs effect, are reviewed.

Viral transduction of the HER2-extracellular domain expands trastuzumab-based photoimmunotherapy for HER2-negative breast cancer cells.

The prognosis of HER2-positive breast cancer has been improved by trastuzumab therapy, which features high specificity and limited side effects. However, trastuzumab-based therapy has shortcomings. Firstly, HER2-targeted therapy is only applicable to HER2-expressing tumors, which comprise only 20-25% of primary breast cancers. Secondly, many patients who initially respond to trastuzumab ultimately develop disease progression. To overcome these problems, we employed virus-mediated HER2 transduction and photoimmunotherapy (PIT) which involves trastuzumab conjugated with a photosensitizer, trastuzumab-IR700, and irradiation of near-infrared light. We hypothesized that the gene transduction technique together with PIT would expand the range of tumor entities suitable for trastuzumab-based therapy and improve its antitumor activity. The HER2-extracellular domain (ECD) was transduced by the adenoviral vector, Ad-HER2-ECD, and PIT with trastuzumab-IR700 was applied in the HER2-negative cancer cells. Ad-HER2-ECD can efficiently transduce HER2-ECD into HER2-negative human cancer cells. PIT with trastuzumab-IR700 induced direct cell membrane destruction of Ad-HER2-ECD-transduced HER2-negative cancer cells. Novel combination of viral transduction of a target antigen and an antibody-based PIT would expand and potentiate molecular-targeted therapy even for target-negative or attenuated cancer cells.