Systemic targeted therapy for her2-positive early female breast cancer: a systematic review of the evidence for the 2014 Cancer Care Ontario systemic therapy guideline

Anterior gradient-2 regulates cell communication by coordinating cytokine-chemokine signaling and immune infiltration in breast cancer

Anterior gradient-2 (AGR2) is crucial to breast cancer progression. However, its role in the tumor immune microenvironment remains unclear. RNA sequencing expression profiles and associated clinical information were downloaded from The Cancer Genome Atlas and Gene Expression Omnibus databases, respectively. The AGR2 expression patterns were verified using clinical samples of breast cancer. Based on single-cell transcriptomic data, AGR2 expression patterns were identified and cell communication analysis was carried out. Furthermore, the roles of AGR2 in breast tumor progression were explored by a series of functional experiments. We found that DNA methylation was an important mechanism for regulating the expression patterns of AGR2. Patients with AGR2 low expression displayed an immune "hot" and immunosuppressive phenotype characterized by high abundance of tumor immune cell infiltration and increased enrichment scores for transforming growth factor-β (TGF-β) and epithelial-mesenchymal transition pathways, whereas patients with AGR2 high expression showed an opposite immunologic feature with a lack of immune cell infiltration, suggestive of an immune "cold" and desert phenotype. Moreover, single-cell analysis further revealed that AGR2 in malignant cells alters cell-cell interactions by coordinating cytokine-chemokine signaling and immune infiltration. Notably, two immunotherapy cohorts revealed that AGR2-coexpressed genes could serve as prognostic indicators of patient survival. In conclusion, AGR2 could promote breast cancer progression by affecting the tumor immune microenvironment. Patients with AGR2 low expression could be suitable for combination treatment with immune checkpoint inhibitor agents and TGF-β blockers. Therefore, this study provides a theoretical foundation for developing a strategy for personalized immunotherapy to patients with breast cancer.

Health-related quality of life in Her2-positive early breast cancer woman using trastuzumab: A systematic review and meta-analysis

Background: Despite the benefits of trastuzumab in many trials, evidence of its impact on health-related quality of life (HRQoL) in early treatment has not been summarized. This study explored the effects of trastuzumab treatment on HRQoL, including pooled meta-analysis, in an effort to provide an integrated assessment of HRQoL for Her2-positive early breast cancer patients. Methods: A comprehensive literature review to February 2023 using three databases, focusing on treatment using trastuzumab during the early stage, was performed. The mean changes from baseline during and after treatment were extracted from the included randomized control trials (RCTs) papers and total HRQoL scores were obtained from cross-sectional studies included. Mean difference (MD) and 95% confidence intervals were assessed by a random effect or fixed effect model based on heterogeneity (I²). Results: A total of ten studies were identified and reviewed, consisting of seven RCTs and three cross-sectional studies. The pooled analysis of the mean change from baseline during treatment resulted in an MD of 1.92 (95% CI = 1.59 to 2.25, p < 0.05, I² = 0%), favoring the trastuzumab group. A non-significant result of the mean change from baseline after treatment appeared in the analysis of 12-month follow-up. In the cross-sectional studies, pooled analyses of HRQoL showed that trastuzumab meaningfully demonstrated an improved HRQoL profile (MD = 9.29, 95% CI = 1.31 to 17.27, p = 0.02, I² = 0%). Conclusion: Trastuzumab as a targeted therapy resulted in a favorable effect on HRQoL in the early stages of Her2-positive breast cancer. The findings of significant improvements in patients' HRQoL and less clinically meaningful deterioration in side effects of trastuzumab-containing regimen during treatment were supported by prolonged survival.

Appraising the quality of meta-analysis for breast cancer treatment in the adjuvant setting: A systematic review

INTRODUCTION

Breast cancer is the tumor with highest incidence in women worldwide and adjuvant treatment is extremely important to achieve disease control. Given the relevance of systematic reviews, their rigor should be warranted to avoid biased conclusions. Our objective was to investigate the methodological quality of meta-analysis of early breast cancer adjuvant treatment.

MATERIAL AND METHODS

Comprehensive searches were performed using electronic databases from 1/1/2007 to 11/12/2018. All studies identified as a systematic review with meta-analysis investigating the efficacy of breast cancer adjuvant treatments were included. Two reviewers independently assessed titles and abstracts, then full-texts for eligibility. Quality was assessed using the Assessing the Methodological Quality of Systematic Reviews (AMSTAR) version 2 tool.

RESULTS

Of 950 citations retrieved, 66 studies (7.0%) were deemed eligible. Methodological quality was highly variable, median AMSTAR score 8.5 (IQR 7-9.5) and range 0-16. There was a weak positive correlation between journal impact factor and AMSTAR score (r = 0.17) and citation rate and AMSTAR score (r = 0.16). Cochrane Systematic Reviews were of higher quality than reviews from other journals. Overall confidence was critically low for 61 (92.4%) studies, and the least well-reported domains were the statement of conflict of interest and funding source for the included studies (4.6%), the report of a pre-defined study protocol (15.2%), and the description of details of excluded studies (6.1%).

CONCLUSIONS

Our findings reinforce concerns about the design, conduction and interpretation of meta-analysis in current literature. Methodological quality should be carefully considered and journal editors, decision makers and readers in general, must follow a critical approach to this studies.

The adverse effects of bisphosphonates in breast cancer: A systematic review and network meta-analysis

BACKGROUND

Bisphosphonate drugs can be used to improve the outcomes of women with breast cancer. Whilst many meta-analyses have quantified their potential benefits for patients, attempts at comprehensive quantification of potential adverse effects have been limited. We undertook a meta-analysis with novel methodology to identify and quantify these adverse effects.

METHODS

We systematically reviewed randomised controlled trials in breast cancer where at least one of the treatments was a bisphosphonate (zoledronic acid, ibandronate, pamidronate, alendronate or clodronate). Neoadjuvant, adjuvant and metastatic settings were examined. Primary outcomes were adverse events of any type or severity (excluding death). We carried out pairwise and network meta-analyses to estimate the size of any adverse effects potentially related to bisphosphonates. In order to ascertain whether adverse effects differed by individual factors such as age, or interacted with other common adjuvant breast cancer treatments, we examined individual-level patient data for one large trial, AZURE.

FINDINGS

We identified 56 trials that reported adverse data, which included a total of 29,248 patients (18,301 receiving bisphosphonate drugs versus 10,947 not). 24 out of the 103 different adverse outcomes analysed showed a statistically and practically significant increase in patients receiving a bisphosphonate drug compared with those not (2 additional outcomes that appeared statistically significant came only from small studies with low event counts and no clinical suspicion so are likely artifacts). Most of these 24 are already clinically recognised: 'flu-like symptoms, fever, headache and chills; increased bone pain, arthralgia, myalgia, back pain; cardiac events, thromboembolic events; hypocalcaemia and osteonecrosis of the jaw; as well as possibly stiffness and nausea. Oral clodronate appeared to increase the risk of vomiting and diarrhoea (which may also be increased by other bisphosphonates), and there may be some hepatotoxicity. Four additional potential adverse effects emerged for bisphosphonate drugs in this analysis which have not classically be recognised: fatigue, neurosensory problems, hypertonia/muscle spasms and possibly dysgeusia. Several symptoms previously reported as potential side effects in the literature were not significantly increased in this analysis: constipation, insomnia, respiratory problems, oedema or thirst/dry mouth. Individual patient-level data and subgroup analysis revealed little variation in side effects between women of different ages or menopausal status, those with metastatic versus non-metastatic cancer, or between women receiving different concurrent breast cancer therapies.

CONCLUSIONS

This meta-analysis has produced estimates for the absolute frequencies of a range of side effects significantly associated with bisphosphonate drugs when used by breast cancer patients. These results show good agreement with previous literature on the subject but are the first systematic quantification of side effects and their severities. However, the analysis is limited by the availability and quality of data on adverse events, and the potential for bias introduced by a lack of standards for reporting of such events. We therefore present a table of adverse effects for bisphosphonates, identified and quantified to the best of our ability from a large number of trials, which we hope can be used to improve the communication of the potential harms of these drugs to patients and their healthcare providers.

Overview of New Treatments with Immunotherapy for Breast Cancer and a Proposal of a Combination Therapy

According to data from the U.S. National Cancer Institute, cancer is one of the leading causes of death worldwide with approximately 14 million new cases and 8.2 million cancer-related deaths in 2018. More than 60% of the new annual cases in the world occur in Africa, Asia, Central America, and South America, with 70% of cancer deaths in these regions. Breast cancer is the most common cancer in women, with 266,120 new cases in American women and an estimated 40,920 deaths for 2018. Approximately one in six women diagnosed with breast cancer will die in the coming years. Recently, novel therapeutic strategies have been implemented in the fight against breast cancer, including molecules able to block signaling pathways, an inhibitor of poly [ADP-ribose] polymerase (PARP), growth receptor blocker antibodies, or those that reactivate the immune system by inhibiting the activities of inhibitory receptors like cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed death protein 1 (PD-1). However, novel targets include reactivating the Th1 immune response, changing tumor microenvironment, and co-activation of other components of the immune response such as natural killer cells and CD8+ T cells among others. In this article, we review advances in the treatment of breast cancer focused essentially on immunomodulatory drugs in targeted cancer therapy. Based on this knowledge, we formulate a proposal for the implementation of combined therapy using an extracorporeal immune response reactivation model and cytokines plus modulating antibodies for co-activation of the Th1- and natural killer cell (NK)-dependent immune response, either in situ or through autologous cell therapy. The implementation of "combination immunotherapy" is new hope in breast cancer treatment. Therefore, we consider the coordinated activation of each cell of the immune response that would probably produce better outcomes. Although more research is required, the results recently achieved by combination therapy suggest that for most, if not all, cancer patients, this tailored therapy may become a realistic approach in the near future.

Current immunoassay methods and their applications to clinically used biomarkers of breast cancer

Breast cancer is the leading cause of cancer-related mortality worldwide, with a higher incidence in developed countries. The biomarkers for breast cancer such as estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, CA (cancer antigen) 15-3, CA 27.29, and carcinoembryonic antigen have been recommended for use in the laboratory based on the guidelines of American and European societies. Immunoassays have been frequently and consistently used to detect these clinically established biomarkers of breast cancer. Despite the higher accessibility of serum biomarkers, including CA 15-3, CA 27.29, and CEA, compared to tissue markers, variations in immunoassays affect their standardization and clinical utility. When reviewing the immunoassays used to detect these serum markers, we found that the most frequently used immunoassay was enzyme-linked immunosorbent assay, followed by electrochemiluminescent immunoassay, and then chemiluminescence immunoassay for CA 15-3 and CEA. Meanwhile, the chemiluminescence immunoassay was the most common technique for CA27.29. The electrochemiluminescent immunoassay and monoclonal fluorometric assay have become the preferred methods in 2010-2019 compared to 2000-2009. Analytical and clinical performance factors such as sensitivity, specificity, detection limit, hazard risk to laboratory personnel, speed, and economic feasibility influenced these changes in user preference. When using the immunoassays, there should be a comprehensive understanding of the principles, advantages, vulnerability, and precautions for interpretation. In the future, a combination of immunological biomarkers and genetic platforms will benefit patients with breast cancer by facilitating prognosis prediction and guiding therapeutic intervention.

Overview of Basic Mechanisms of Notch Signaling in Development and Disease

Notch signaling is an evolutionarily conserved pathway associated with the development and differentiation of all metazoans. It is needed for proper germ layer formation and segmentation of the embryo and controls the timing and duration of differentiation events in a dynamic manner. Perturbations of Notch signaling result in blockades of developmental cascades, developmental anomalies, and cancers. An in-depth understanding of Notch signaling is thus required to comprehend the basis of development and cancer, and can be further exploited to understand and direct the outcomes of targeted cellular differentiation into desired cell types and complex tissues from pluripotent or adult stem and progenitor cells. In this chapter, we briefly summarize the molecular, evolutionary, and developmental basis of Notch signaling. We will focus on understanding the basics of Notch signaling and its signaling control mechanisms, its developmental outcomes and perturbations leading to developmental defects, as well as have a brief look at mutations of the Notch signaling pathway causing human hereditary disorders or cancers.

Adjuvant trastuzumab regimen for HER2-positive early-stage breast cancer: a systematic review and meta-analysis

Objective: Breast cancer remains to be the globally leading female cancer. About 15% to 20% of breast cancers have human epidermal growth factor receptor 2 (HER2)-positive tumors - a more aggressive breast cancer subtype with shortened survival. In the light of new and updated trial data on trastuzumab therapy for HER2-positive early-stage breast cancer (EBC), we conducted a systematic review and meta-analysis to update the pooling of its relative treatment effects. Methods: Systematic search was performed through Pubmed and Scopus to identify studies comparing survival outcomes and risks of heart toxicity effects of adjuvant trastuzumab with chemotherapy versus chemotherapy alone for HER2-positive EBC patients. Results: Based on the eight included studies in the review, combining trastuzumab with chemotherapy continues to show lowered death and relapse risks by one-third. The decision to initiate trastuzumab, however, needs to be prudently deliberated as two to three times more cardiotoxicity risk was shown to be associated with its use. Conclusion: Administering adjuvant trastuzumab in a weekly cycle concurrently with anthracycline-taxane chemotherapy regimen appears to be a preferable option to optimize its favorable effect in improving DFS and to prevent significantly higher risk for cardiotoxic effects.

ERBB2 Regulates MED24 during Cancer Progression in Mice with Pten and Smad4 Deletion in the Pulmonary Epithelium

ERBB2 is an oncogenic driver with frequent gene mutations and amplification in human lung tumors and is an attractive target for lung cancer therapy. However, target therapies can be improved by understanding the in vivo mechanisms regulated by ERBB2 during lung tumor development. Here, we generated genetic mouse models to show that Erbb2 loss inhibited lung tumor development induced by deletion of Pten and Smad4. Transcriptome analysis showed that Erbb2 loss suppressed the significant changes of most of the induced genes by ablation of Pten and Smad4. Overlapping with ERBB2-associated human lung cancer genes further identified those ERBB2 downstream players potentially conserved in human and mouse lung tumors. Furthermore, MED24 was identified as a crucial oncogenic target of ERBB2 in lung tumor development. Taken together, ERBB2 is required for the dysregulation of cancer-related genes, such as MED24, during lung tumor development.

The renaissance of anti-neoplastic immunity from tumor cell demise

Cancer therapies can temporarily reduce tumor burdens by inducing malignant cell death. However, cancer cure is still far from realization because tumors often gain resistance to current treatment and eventually relapse. Accumulating evidence suggests that successful cancer interventions require anti-tumor immunity. Therapy-induced cell stress responses ultimately result in one or more cell death modalities, including apoptosis, autophagy, necroptosis, and pyroptosis. These irreversible dying processes are accompanied by active or passive release of cell death-associated molecular patterns (CDAMPs), which can be sensed by corresponding pattern recognition receptors (PRR) on tumor-infiltrating immune cells. This crosstalk with the immune system can reawaken immune surveillance in the tumor microenvironment (TME). This review focuses on immune-modulatory properties of anti-cancer regimens and CDAMP-mediated communications between cell stress responses and the immune contexture of TME. In addition, we describe how immunogenic cell death can elicit strong and durable anti-tumor immune responses.

Real-World Data on Health-Related Quality of Life Assessment in Patients With Breast Cancer Receiving Subcutaneous Trastuzumab

Purpose

Trastuzumab, a humanized anti-human epidermal growth factor receptor 2 (anti-HER2) antibody delivered intravenously, has revolutionized the treatment of patients with breast cancer overexpressing HER2 protein. Recently, a newer subcutaneous formulation was shown to have comparable efficacy to the initial intravenous trastuzumab. In this study, we aimed to evaluate the impact of subcutaneous trastuzumab on the health-related quality of life (HRQoL) of patients diagnosed with early or metastatic HER2-overexpressing breast cancer.

Methods

Patients were provided with the EORTC QLQ-C30 (European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire-Core 30) and the BR-23 questionnaires. The scoring of questionnaires and patient's sociodemographic and clinicopathologic characteristics were recorded and analyzed by descriptive and correlation statistics employing t test and 2-way analysis of variance.

Results

A total of 163 patients agreed to participate in the study. About 90 of 163 patients (55.21%) received subcutaneous trastuzumab and 21 patients intravenous trastuzumab (12.88%). A control group of 52 HER2+ patients received chemotherapy without trastuzumab (31.90%). Patients receiving subcutaneous trastuzumab were older and of more advanced disease stage compared with those receiving chemotherapy (58.5 vs 51 years, 39.8% vs 28.8% advanced disease). In univariate analysis, subcutaneous trastuzumab was associated with less nausea and vomiting (P = .002) but worse cognitive function (P = .013) and dyspnea (P = .042). Patients who have received >8 cycles of subcutaneous trastuzumab reported less diarrhea (P = .049) and systemic therapy side effects (P = .015). Multivariate analysis showed that patients without comorbidity receiving subcutaneous trastuzumab had less treatment side effects, less upset by hair loss, and higher emotional functioning. Of note, mastectomy and subcutaneous trastuzumab were associated with improved role functioning (P = .021). In metastatic disease, no negative impact of subcutaneous trastuzumab on HRQoL was found.

Conclusions

The administration of subcutaneous trastuzumab improved certain symptoms and did not adversely affect most of the assessed functional scales. Particularly, in the metastatic setting, subcutaneous trastuzumab had no negative impact on HRQoL.

The landscape of somatic mutations in Indonesian cervical cancer is predominated by the PI3K pathway

OBJECTIVE

To investigate the prevalence of somatic mutations in Indonesian cervical carcinoma patients in the context of histology and human papillomavirus (HPV) type.

METHODS

In total 174 somatic hot-spot mutations in 13 genes were analyzed by mass spectrometry in 137 Indonesian cervical carcinomas.

RESULTS

In 66/137 tumors (48%) 95 mutations were identified. PIK3CA was most frequently mutated (24%), followed by FBXW7 (7%), CTNNB1 (6%), and PTEN (6%). In squamous cell carcinomas more often multiple mutations per sample (p=0.040), and more PIK3CA (p=0.039) and CTNNB1 (p=0.038) mutations were detected compared to adenocarcinomas. PIK3CA mutations were associated with HPV 16 positivity, CDKN2A mutations with HPV 52 positivity, and, interestingly, PTEN mutations with HPV negativity. Balinese tumor samples more often carried multiple mutations (p=0.019), and more CTNNB1, CDKN2A, and NRAS mutations compared to Javanese tumor samples.

CONCLUSIONS

Potentially targetable somatic mutations occurred in 48% of Indonesian cervical carcinomas. The landscape of mutations is predominated by mutations concerning the PI3K pathway, and we prompt for more research on developing therapies targeting this pathway, explicitly for the more advanced stage cervical carcinoma patients.

Addressing the challenges of applying precision oncology

Precision oncology is described as the matching of the most accurate and effective treatments with the individual cancer patient. Identification of important gene mutations, such as BRCA1/2 that drive carcinogenesis, helped pave the way for precision diagnosis in cancer. Oncoproteins and their signaling pathways have been extensively studied, leading to the development of target-based precision therapies against several types of cancers. Although many challenges exist that could hinder the success of precision oncology, cutting-edge tools for precision diagnosis and precision therapy will assist in overcoming many of these difficulties. Based on the continued rapid progression of genomic analysis, drug development, and clinical trial design, precision oncology will ultimately become the standard of care in cancer therapeutics.

Efficacy and safety of short course adjuvant trastuzumab combination chemotherapy in breast cancer

Background:

The adjuvant short course 9-week trastuzumab combination therapy for human epidermal receptor 2 positive breast cancer patients may often be considered as a cost-effective and safe option and has important implications for the Indian subcontinent as well as other developing countries. However, such regimens of shorter duration trastuzumab therapy like FinHer, offered in view of economic constraints, may not be able to achieve globally comparable cure rates in early breast cancer especially with high-risk women with more than 3 lymph node positive.

Methods and Material:

Outcome of 21 patients with HER2 positive breast cancer was treated with short course trastuzumab combination chemotherapy in the adjuvant setting was studied.

Results:

Out of 21 patients 15 are alive and disease free with a follow up of up to 73 months (median follow up 42 months).

Multi-parametric analysis reveals enhanced G2-phase arrest of an optimized anti-HER2 antibody to inhibit breast cancer

OBJECTIVES

To find a "me-better" antibody by epitope-specific antibody optimization and multi-parametric analysis.

RESULTS

Using epitope-specific library based on the commercial drug, Pertuzumab/2C4, we screened a novel human anti-HER2 antibody, MIL5, which has slightly higher affinity than the drug. MIL5 and 2C4 share the same epitope to bind HER2; however, MIL5 bound to HER2 His235-His245 more tightly than 2C4, which could be the main reason of its enhanced affinity. In vivo experiments also showed MIL5 had stronger anti-cancer activity than 2C4; however, the classical flow cytometry assays to detect cell apoptosis or cycling did not show convincing evidence of the advantages of MIL5. Thus we introduced the multi-parameter in-cell analysis method to evaluate the superiority of MIL5 to 2C4 in arresting cancer cells in G2-phase to inhibit cell growth and/or proliferation.

CONCLUSION

Multi-parametric method confirmed stronger arrest of G2 by MIL5 to show better anti-cancer function both in vitro and in vivo than 2C4.

Peptide probes derived from pertuzumab by molecular dynamics modeling for HER2 positive tumor imaging

A high level of HER2 expression in breast cancer correlates with a higher tumor growth rate, high metastatic potential, and a poor long-term patient survival rate. Pertuzumab, a human monoclonal antibody, can reduce the effect of HER2 overexpression by preventing HER2 dimerization. In this study, a combination protocol of molecular dynamics modeling and MM/GBSA binding free energy calculations was applied to design peptides that interact with HER2 based on the HER2/pertuzumab crystal structure. Based on a β hairpin in pertuzumab from Glu46 to Lys65—which plays a key role in interacting with HER2—mutations were carried out in silico to improve the binding free energy of the hairpin that interacts with the Phe256-Lys314 of the HER2 protein. Combined the use of one-bead-one-compound library screening, among all the mutations, a peptide (58F63Y) with the lowest binding free energy was confirmed experimentally to have the highest affinity, and it may be used as a new probe in diagnosing and treating HER2-positive breast cancer.

Many therapeutic approaches, including the human monoclonal antibodies trastuzumab and pertuzumab, target the human epidermal growth factor receptor 2 (HER2) of any breast cancer that features HER2 overexpression. Compared to these antibodies, peptides have many advantages, including lower cost, easier synthesis, high affinity, and lower toxicity. Here, we first designed peptides that interact with HER2 protein based on the HER2/pertuzumab crystal structure (PDB entry: 1S78), using a combination protocol of molecular dynamics modeling, molecular mechanics/generalized Born solvent-accessible surface area (MM/GBSA) binding free energy calculations. Then, combined with the peptide library screening, six peptides were selected for further analysis and experimental validations. The results of ex vivo and in vivo experiments confirmed that one peptide (58F63Y) in particular has a strong affinity and high specificity to HER2-overexpressing tumors. This may due to more paired residues and lower binding free energy in peptide 58F63Y and HER2 complex based on free energy decomposition analysis and distances calculation. While both in silico and in vitro screenings point to the same high-affinity peptide, the findings suggest that in silico screening based on calculated binding free energies is rather reliable. Additionally, based on the calculation of binding free energies among mutants, we can reduce the library capacity of one-bead-one-compound screening. In summary, we present a rather simple and rapid means of deriving a peptide with a clear binding site to its target protein.

Increased trace amine-associated receptor 1 (TAAR1) expression is associated with a positive survival rate in patients with breast cancer

PURPOSE

A correlation between breast cancer and thyroid disorders has been described in previous studies. Degraded thyroid hormones are referred to as trace amines. These endogenous amines have the ability to bind to the G-protein-coupled receptor TAAR1 (trace amine-associated receptor) and thereby activate it. TAAR1 is able to modulate the serotonergic and dopaminergic system in the brain and has so far been studied in the neurological field. The following study represents the first investigation of the regulation of TAAR1 in primary breast cancer (no metastases, M0).

METHODS

Immunohistochemical analyses were carried out to detect TAAR1 expression in formalin fixed paraffin embedded breast cancer samples. Survival times of primary breast cancer patients (M0) with and without TAAR1 expression in their tumours were compared by Kaplan-Meier curves, and correlations between ordinal variables were determined with Spearman's rank correlation coefficient.

RESULTS

The investigation showed a correlation between TAAR1 expression and tumour differentiation grade. A well differentiated tumour grade (G1) was associated with higher TAAR1 expression and HER2 and HER4 positivity predicted higher TAAR1 expression. A TAAR1 overexpression (IRS ≥ 6) was associated with significantly longer overall survival (OS) (p = 0.02) than that of reduced TAAR1 expression (IRS < 6) during a maximum follow-up of 14 years, demonstrating that TAAR1 has a favourable effect on OS of early breast cancer patients.

CONCLUSIONS

We conclude that TAAR1 seems to be an independent predictor for breast cancer survival. Modulation of TAAR1 may represent a novel targeting strategy for breast cancer prevention and therapy.

Restricted Axillary Staging in Clinically and Sonographically Node-Negative Early Invasive Breast Cancer (c/iT1-2) in the Context of Breast Conserving Therapy: First Results Following Commencement of the Intergroup-Sentinel-Mamma (INSEMA) Trial

Axillary lymph node status remains an important prognostic factor in early breast cancer. It is regarded as an indicator for (neo)adjuvant systemic treatment and postoperative radiotherapy of the regional lymphatics. Commenced in September 2015, the INSEMA trial is investigating whether operative determination of nodal status as part of breast conserving therapy (BCT) for early stage breast cancer (c/iT1-2 c/iN0) can be avoided without reducing oncological safety. After inclusion of 1001 patients there was general acceptance of the complex study design by patients and study doctors so that recruitment for the first randomisation (axillary sentinel lymph node biopsy [SLNB]: yes or no) achieved predicted case numbers. The second randomisation however (SLNB alone versus complete axillary dissection when one or two macrometastases are present at SLNB) recruited fewer cases than expected for the following three reasons: a) the 13 % rate of one or two macrometastases after SLNB in the INSEMA trial collective was lower than expected; b) around 20 % of patients refused the second randomisation; c) there was delayed inclusion of the Austrian study centres, which only recruited for the second randomisation. Lack of knowledge of nodal status when SLNB is avoided represents a new challenge for the postoperative tumour board. In particular decisions on chemotherapy for luminal-like tumours and irradiation of the lymphatics (excluding axilla) must be guided by tumour biological parameters. The INSEMA trial does not provide answers to some important questions, e.g. it remains unclear whether patients without SLNB can be offered partial breast irradiation alone in low-risk situations and whether SLNB can also be avoided in patients with stage T1-2 tumours who have a mastectomy indication.

The Treatment of Primary Breast Cancer in Older Women With Adjuvant Therapy: A Retrospective Analysis of Data From Over 3000 Patients From the PATH Biobank, With Two-Year Follow-up

BACKGROUND

Breast cancer is the most common cancer in women in Germany. Mortality from breast cancer has declined over the past 15 years, but less so in women aged 70 or older than in younger women. The discrepancy might be explained by age-related differences in treatment.

METHODS

Data from the Patients' Tumor Bank of Hope (PATH) database of women who underwent adjuvant treatment for the treatment of an invasive primary tumor without distant metastases (year of diagnosis, 2006-2011) were retrospectively analyzed. The clinical and tumor-biological findings and treatment data over two years of follow-up were compared across three age groups (under age 50, ages 50 to 69, and ages 70 and up). Chi-square tests were carried out to reveal significant differences, and post-hoc multiple comparisons were performed with and without Bonferroni correction. Treatment data were adjusted for staging and grading and tested for age-dependence with logistic regression.

RESULTS

Follow-up data were available for 3257 (65% ) of 4981 women, of whom 61% were in the middle age group and 22% in the oldest. Compared to women aged 50 to 69, those aged 70 and up less commonly received breast-conserving treatment (68.8% vs. 86.4% ), chemotherapy (27.5% vs. 44.1% ), radiotherapy (81.8% vs. 92.4% ), and trastuzumab (52.9% vs. 79.3% ; p<0.001 for all differences). All differences remained significant after stastistical adjustment.

CONCLUSION

The cause of these age-related differences is unclear. It cannot be determined from these data whether concomitant disease, the older patients' individual decisions, or other factors were responsible for their not receiving treatment as often as the younger patients did.

The erbB3- and IGF-1 receptor-initiated signaling pathways exhibit distinct effects on lapatinib sensitivity against trastuzumab-resistant breast cancer cells

Both erbB3 and IGF-1 receptor (IGF-1R) have been shown to play an important role in trastuzumab resistance. However, it remains unclear whether erbB3- and IGF-1R-initiated signaling pathways possess distinct effects on the sensitivity of lapatinib, a dual tyrosine kinase inhibitor against both EGFR and erbB2, in trastuzumab-resistant breast cancer. Here, we show that the trastuzumab-resistant SKBR3-pool2 and BT474-HR20 breast cancer sublines, as compared the parental SKBR3 and BT474 cells, respectively, exhibit refractoriness to lapatinib. Knockdown of erbB3 inhibited Akt in SKBR3-pool2 and BT474-HR20 cells, significantly increased lapatinib efficacy, and dramatically re-sensitized the cells to lapatinib-induced apoptosis. In contrast, specific knockdown of IGF-1R did not alter the cells' responsiveness to lapatinib. While the levels of phosphorylated Src (P-Src) were reduced upon IGF-1R downregulation, the P-Akt levels remained unchanged. Furthermore, a specific inhibitor of Akt, but not Src, significantly enhanced lapatinib-mediated anti-proliferative/anti-survival effects on SKBR3-pool2 and BT474-HR20 cells. These data indicate that erbB3 signaling is critical for both trastuzumab and lapatinib resistances mainly through the PI-3K/Akt pathway, whereas IGF-1R-initiated Src activation results in trastuzumab resistance without affecting lapatinib sensitivity. Our findings may facilitate the development of precision therapeutic regimens for erbB2-positive breast cancer patients who become resistant to erbB2-targeted therapy.