The relationship between prognostic and predictive factors in the management of breast cancer

Time-related survival prediction in molecular subtypes of breast cancer using time-to-event deep-learning-based models

Background

Breast cancer (BC) survival prediction can be a helpful tool for identifying important factors selecting the effective treatment reducing mortality rates. This study aims to predict the time-related survival probability of BC patients in different molecular subtypes over 30 years of follow-up.

Materials and methods

This study retrospectively analyzed 3580 patients diagnosed with invasive breast cancer (BC) from 1991 to 2021 in the Cancer Research Center of Shahid Beheshti University of Medical Science. The dataset contained 18 predictor variables and two dependent variables, which referred to the survival status of patients and the time patients survived from diagnosis. Feature importance was performed using the random forest algorithm to identify significant prognostic factors. Time-to-event deep-learning-based models, including Nnet-survival, DeepHit, DeepSurve, NMLTR and Cox-time, were developed using a grid search approach with all variables initially and then with only the most important variables selected from feature importance. The performance metrics used to determine the best-performing model were C-index and IBS. Additionally, the dataset was clustered based on molecular receptor status (i.e., luminal A, luminal B, HER2-enriched, and triple-negative), and the best-performing prediction model was used to estimate survival probability for each molecular subtype.

Results

The random forest method identified tumor state, age at diagnosis, and lymph node status as the best subset of variables for predicting breast cancer (BC) survival probabilities. All models yielded very close performance, with Nnet-survival (C-index=0.77, IBS=0.13) slightly higher using all 18 variables or the three most important variables. The results showed that the Luminal A had the highest predicted BC survival probabilities, while triple-negative and HER2-enriched had the lowest predicted survival probabilities over time. Additionally, the luminal B subtype followed a similar trend as luminal A for the first five years, after which the predicted survival probability decreased steadily in 10- and 15-year intervals.

Conclusion

This study provides valuable insight into the survival probability of patients based on their molecular receptor status, particularly for HER2-positive patients. This information can be used by healthcare providers to make informed decisions regarding the appropriateness of medical interventions for high-risk patients. Future clinical trials should further explore the response of different molecular subtypes to treatment in order to optimize the efficacy of breast cancer treatments.

Correlation of the Ki67 Working Group prognostic risk categories with the Oncotype DX Recurrence Score in early breast cancer

BACKGROUND

The relationship between Ki67 assessed by immunohistochemistry (IHC) and the Oncotype DX Recurrence Score (RS) is unclear. The objective of this study was to determine the correlation between the 21-gene RS and IHC-measured Ki67 with the prognostic classification groups recommended by the International Ki67 Working Group (IKWG).

METHODS

The authors performed a retrospective chart review of women who had hormone receptor (HR)-positive, human epidermal growth factor receptor 2-negative early breast cancer with zero to three positive lymph nodes and both Ki67 and the 21-gene RS performed at their institution from 2013 to 2021. Patients were categorized into low (≤5%), intermediate (6%-29%), and high Ki67 groups (≥30%) according to IKWG recommendations. Overall agreement and risk-stratified agreement between Ki67 and RS were assessed with the proportion of agreement and the κ statistic.

RESULTS

The study included 525 patients with HR-positive breast cancer. Among the 49% of patients with intermediate Ki67 values of 6%-29%, the distribution of low (0-10), intermediate (11-25), and high RS (26-100) was 19%, 66%, and 15%, respectively. There was slight agreement (κ = 0.01-0.20) between Ki67 and RS (κ = 0.027) in the overall population, although this was not significant (p = .1985). There was fair agreement (κ = 0.21-0.40) between high Ki67 and RS values (κ = 0.280; p < .0001). A higher progesterone receptor percentage was associated with lower RS values (p > .0001) but not lower Ki67 values. A positive nodal status and a larger tumor size were associated with higher Ki67 values (p = .0059 and p < .0001) but not with RS.

CONCLUSIONS

In this group of patients selected to have a 21-gene RS, there was no significant correlation between Ki67 and RS in the overall population, and there was fair agreement between high Ki67 and high RS values.

LAY SUMMARY

In patients with early-stage, hormone receptor-positive breast cancer, decisions on adjuvant chemotherapy are based on certain biological features of the cancer and genomic assays such as the Oncotype DX Recurrence Score (RS). The goal of this study was to determine the correlation between Ki67, a marker of proliferation, and the Oncotype DX RS, a 21-gene assay demonstrated to be predictive of an adjuvant chemotherapy benefit in patients with early-stage breast cancer. In 525 patients, the authors did not find a significant correlation between Ki67 and RS.

Depletion of Mdig Changes Proteomic Profiling in Triple Negative Breast Cancer Cells

Triple-negative breast cancers are highly aggressive with an overall poor prognosis and limited therapeutic options. We had previously investigated the role of mdig, an oncogenic gene induced by some environmental risk factors, on the pathogenesis of breast cancer. However, a comprehensive analysis of the proteomic profile affected by mdig in triple-negative breast cancer has not been determined yet. Using label-free bottom-up quantitative proteomics, we compared wildtype control and mdig knockout MDA-MB-231 cells and identified the proteins and pathways that are significantly altered with mdig deletion. A total of 904 differentially expressed (p < 0.005) proteins were identified in the KO cells. Approximately 30 pathways and networks linked to the pathogenicity of breast cancer were either up- or downregulated, such as EIF2 signaling, the unfolded protein response, and isoleucine degradation I. Ingenuity Pathway Analysis established that the differentially expressed proteins have relevant biological actions in cell growth, motility, and malignancy. These data provide the first insight into protein expression patterns in breast cancer associated with a complete disruption of the mdig gene and yielded substantial information on the key proteins, biological processes, and pathways modulated by mdig that contribute to breast cancer tumorigenicity and invasiveness.

Histamine H4 Receptor Expression in Triple-negative Breast Cancer: An Exploratory Study

Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype. There are neither universally accepted prognostic markers nor molecular targets related to TNBC. The histamine H4 receptor (H4R) has been characterized in TNBC experimental models, demonstrating its critical role in tumor development and progression. In this study, H4R expression was compared in breast cancer subtypes and correlated with clinical features using The Cancer Genome Atlas data (Pan-Cancer Atlas). The H4R status was further evaluated by immunohistochemistry in 30 TNBC human samples in relation to clinicopathological parameters. Results indicate that H4R was downregulated in basal-like/TNBC compared with luminal A and normal breast-like tumors. The higher expression of H4R was associated with improved progression-free and overall survival outcomes in basal-like/TNBC. H4R immunoreactivity was detected in about 70% of tumors, and its expression was positively correlated with the levels in the histologically normal peritumoral tissue. High H4R expression in peritumoral tissue correlated with reduced number of lymph node involvement and unifocal TNBC, while it was associated with increased patient survival. In conclusion, the H4R might represent a potential prognostic biomarker in TNBC. Further studies in large cohorts are needed to better understand the significance of H4R in breast cancer biology.

Lympho-vascular invasion impacts the prognosis in breast-conserving surgery: a systematic review and meta-analysis

Background

It is estimated that breast cancer (BC) incidence, especially that of early-stage breast cancer cases continues to rise due to increased universal screening. Breast-conserving surgery (BCS) is the main intervention for early-stage BC. Lympho-vascular invasion (LVI) is reported to influence breast cancer prognosis but its prognostic value in breast-conserving treatment is controversial.

Methods

A search was conducted on the Cochrane library, PubMed, Web of Science, and EMBASE from inception to December 1^st, 2021, without language restrictions, to identify studies that explored the prognosis of lympho-vascular invasion in breast-conserving surgery. Reviews of each study were conducted, and data extracted. The meta-analysis was performed with StataSE 16. Study quality assessment was evaluated using the Newcastle–Ottawa Scale.

Results

Overall, 15 studies with 21,704 patients deemed eligible for this study. Event-free survival (EFS), disease-free survival (DFS), overall survival (OS), distant metastases (DM), loco-regional recurrence (LRR), local recurrence (LR), breast recurrence (BR), disease specific survival (DSS), and breast cancer specific survival (BCSS), were extracted from each study. We found that LVI leads to poor OS (HR = 1.46, 95% CI: 1.17–1.83), DM (HR = 2.08, 95% CI: 1.66–2.60) and LR (HR = 2.00, 95% CI: 1.54–2.61).

Conclusions

We confirmed that early-stage BC patients with LVI-positive have poorer OS, DFS, LRR, BCSS, DM and LR following receiving BCS than those LVI-negative patients. Mastectomy, in combination with radical systemic therapies could be considered, especially in those requiring second surgery. How to change the impact of LVI on the local recurrence rate and long-term survival in patients who undergo BCS may be a valuable research direction in the future.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09193-0.

A systematic review of datasets that can help elucidate relationships among gene expression, race, and immunohistochemistry-defined subtypes in breast cancer

Scholarly requirements have led to a massive increase of transcriptomic data in the public domain, with millions of samples available for secondary research. We identified gene-expression datasets representing 10,214 breast-cancer patients in public databases. We focused on datasets that included patient metadata on race and/or immunohistochemistry (IHC) profiling of the ER, PR, and HER-2 proteins. This review provides a summary of these datasets and describes findings from 32 research articles associated with the datasets. These studies have helped to elucidate relationships between IHC, race, and/or treatment options, as well as relationships between IHC status and the breast-cancer intrinsic subtypes. We have also identified broad themes across the analysis methodologies used in these studies, including breast cancer subtyping, deriving predictive biomarkers, identifying differentially expressed genes, and optimizing data processing. Finally, we discuss limitations of prior work and recommend future directions for reusing these datasets in secondary analyses.

Glucocorticoid Receptor: A Multifaceted Actor in Breast Cancer

Breast cancer (BC) is one of the most common cancers in women worldwide. Even though the role of estrogen receptor alpha (ERα) is extensively documented in the development of breast tumors, other members of the nuclear receptor family have emerged as important players. Synthetic glucocorticoids (GCs) such as dexamethasone (dex) are commonly used in BC for their antiemetic, anti-inflammatory, as well as energy and appetite stimulating properties, and to manage the side effects of chemotherapy. However, dex triggers different effects depending on the BC subtype. The glucocorticoid receptor (GR) is also an important marker in BC, as high GR expression is correlated with a poor and good prognosis in ERα-negative and ERα-positive BCs, respectively. Indeed, though it drives the expression of pro-tumorigenic genes in ERα-negative BCs and is involved in resistance to chemotherapy and metastasis formation, dex inhibits estrogen-mediated cell proliferation in ERα-positive BCs. Recently, a new natural ligand for GR called OCDO was identified. OCDO is a cholesterol metabolite with oncogenic properties, triggering mammary cell proliferation in vitro and in vivo. In this review, we summarize recent data on GR signaling and its involvement in tumoral breast tissue, via its different ligands.

Whole slide imaging and colorectal carcinoma: A validation study for tumor budding and stromal differentiation

Whole slide imaging (WSI) has recently received FDA approval for sign out in surgical pathology and some anticipate this to mature into the gold standard. During this transition, it will be important to validate WSI for its intended use. And many studies have validated whole slide imaging by comparing diagnostic accuracy with that of conventual light microscopy (CLM); however, the assessment of histopathologic markers is prone to much more discrepancy. One of the best examples being tumor-bud scoring in colorectal carcinoma. Other signatures, including stromal differentiation or desmoplastic reaction; could better represent the epithelial-mesenchymal transition. The findings in our study suggest stromal differentiation on both digital and glass slides to be much more reproducible (0.3585-0.9368) when compared to tumor budding (0.0968-0.7871). When comparing interobserver variation between glass and digital slides for three observers; stromal differentiation was more reliable on glass slides (0.4492), when compared to its digital counterpart (0.3016). On the other hand, interobserver variation for tumor bud scoring was more reliable on digital (0.1661), than glass slides (0.1026). Overall, there is significant variation between different observers and reproducibility issues present on conventual light microscopy transfer to digital slides. Although it is possible that too much emphasis is being placed on the concordance of WSI with CLM. In future, applications in artificial intelligence may be key to diagnostic precision and improved patient outcomes.

Development and validation of a clinical prediction score for poor postoperative pain control following elective spine surgery

OBJECTIVE

Thirty percent to sixty-four percent of patients experience poorly controlled pain following spine surgery, leading to patient dissatisfaction and poor outcomes. Identification of at-risk patients before surgery could facilitate patient education and personalized clinical care pathways to improve postoperative pain management. Accordingly, the aim of this study was to develop and internally validate a prediction score for poorly controlled postoperative pain in patients undergoing elective spine surgery.

METHODS

A retrospective cohort study was performed in adult patients (≥ 18 years old) consecutively enrolled in the Canadian Spine Outcomes and Research Network registry. All patients underwent elective cervical or thoracolumbar spine surgery and were admitted to the hospital. Poorly controlled postoperative pain was defined as a mean numeric rating scale score for pain at rest of > 4 during the first 24 hours after surgery. Univariable analysis followed by multivariable logistic regression on 25 candidate variables, selected through a systematic review and expert consensus, was used to develop a prediction model using a random 70% sample of the data. The model was transformed into an eight-tier risk-based score that was further simplified into the three-tier Calgary Postoperative Pain After Spine Surgery (CAPPS) score to maximize clinical utility. The CAPPS score was validated using the remaining 30% of the data.

RESULTS

Overall, 57% of 1300 spine surgery patients experienced poorly controlled pain during the first 24 hours after surgery. Seven significant variables associated with poor pain control were incorporated into a prediction model: younger age, female sex, preoperative daily use of opioid medication, higher preoperative neck or back pain intensity, higher Patient Health Questionnaire-9 depression score, surgery involving ≥ 3 motion segments, and fusion surgery. Notably, minimally invasive surgery, body mass index, and revision surgery were not associated with poorly controlled pain. The model was discriminative (C-statistic 0.74, 95% CI 0.71-0.77) and calibrated (Hosmer-Lemeshow goodness-of-fit, p = 0.99) at predicting the outcome. Low-, high-, and extreme-risk groups stratified using the CAPPS score had 32%, 63%, and 85% predicted probability of experiencing poorly controlled pain, respectively, which was mirrored closely by the observed incidence of 37%, 62%, and 81% in the validation cohort.

CONCLUSIONS

Inadequate pain control is common after spine surgery. The internally validated CAPPS score based on 7 easily acquired variables accurately predicted the probability of experiencing poorly controlled pain after spine surgery.

Canonical ErbB-2 isoform and ErbB-2 variant c located in the nucleus drive triple negative breast cancer growth

Triple negative breast cancer (TNBC) refers to tumors that do not express clinically significant levels of estrogen and progesterone receptors, and lack membrane overexpression or gene amplification of ErbB-2/HER2, a receptor tyrosine kinase. Transcriptome and proteome heterogeneity of TNBC poses a major challenge to precision medicine. Clinical biomarkers and targeted therapies for this disease remain elusive, so chemotherapy has been the standard of care for early and metastatic TNBC. Our present findings placed ErbB-2 in an unanticipated scenario: the nucleus of TNBC (NErbB-2). Our study on ErbB-2 alternative splicing events, using a PCR-sequencing approach combined with an RNA interference strategy, revealed that TNBC cells express either the canonical (wild-type) ErbB-2, encoded by transcript variant 1, or the non-canonical ErbB-2 isoform c, encoded by alternative variant 3 (RefSeq), or both. These ErbB-2 isoforms function in the nucleus as transcription factors. Evicting both from the nucleus or silencing isoform c only, blocks TN cell and tumor growth. This reveals not only NErbB-2 canonical and alternative isoforms role as targets of therapy in TNBC, but also isoform c dominant oncogenic potential. Furthermore, we validated our findings in the clinic and observed that NErbB-2 correlates with poor prognosis in primary TN tumors, disclosing NErbB-2 as a novel biomarker for TNBC. Our discoveries challenge the present scenario of drug development for personalized BC medicine that focuses on wild-type RefSeq proteins, which conserve the canonical domains and are located in their classical cellular compartments.

Oncotype DX for Comprehensive Treatment in Male Breast Cancer: A Case Report and Literature Review

Male breast cancer (MBC) is uncommon in clinical practice. Using the 21-gene assay to facilitate decision-making on comprehensive treatment of MBC is rarely reported. This study reports the case of a 53-year-old man with left breast cancer. Modified radical mastectomy was performed. Endocrine treatment was chosen for the patient according to the result of the 21-gene assay, a recommended genomic test of breast cancer. The patient remained in good health without evidence of recurrence at 18-month follow-up. This case provides a reference mode for the comprehensive management of early-stage, estrogen receptor–expressing and lymph node–negative MBC patients.

Immunohistochemical Expression of BRCA1 Protein, ER, PR and Her2/neu in Breast Cancer: A Clinicopathological Study

Breast cancer is a heterogeneous hormone-dependent disease. Potential prognosis depends on the clinicopathological evaluation and assessment of other prognostic indicators. The detection of the oestrogen Receptor (ER), Progesterone Receptor (PR), Human epidermal growth factor receptor 2 (Her2/neu) and BRCA1 oncoprotein is pivotal for prognostic evaluation and to choose the appropriate post-surgical adjuvant therapy beside selecting the proper candidate for genetic counselling.

OBJECTIVES

To detect the immunoexpression of the BRCA1 oncoprotein in mammary invasive ducal carcinoma and its association with the prognostic markers (ER, PR and Her2/neu hormonal receptors) and other clinicopathological parameters to improve the patients' treatment plans.

METHODS

A cross-sectional study design including 83 paraffin blocks and histological slides collected from Al-Jumhoori Medical City Teaching Hospital Laboratory in Mosul and the Central Public Health Laboratory in Baghdad between the 1st of January 2010 to the 13th of March 2012 for patients diagnosed with primary invasive ductal breast carcinomas. Immunohistochemistry (IHC) using monoclonal antibodies against ER, PR, Her2/neu receptors and BRCA1 protein was performed via the fully automated immunostaining instrument 'Ventana Benchmark'.

RESULTS

BRCA1 protein immunoexpression was detected in 20.5% of cases. It was significantly high with increasing tumour grade and stage. Although there was a trend of BRCA1 negativity toward negative ER, PR and Her2 receptors, no significant associations were observed with any of these parameters and the patients' age.

CONCLUSION

Altered BRCA1 expression is significantly associated with advanced tumour grade and stage. High number of cases with negative BRCA1 expression showed negative ER, PR and Her2/neu expression.

A Nomogram To Predict The Overall Survival Of Breast Cancer Patients And Guide The Postoperative Adjuvant Chemotherapy In China

Purpose

We aim to construct a nomogram to predict breast cancer survival and guide postoperative adjuvant chemotherapy in China.

Patients and methods

A total of 5,504 breast cancer patients from the Tianjin Breast Cancer Cases Cohort were included. Multivariable Cox regression was used to investigate the factors associated with overall survival (OS) and a nomogram was constructed based on these prognostic factors. The nomogram was internal and external validated and the performance was evaluated by area under the curve (AUC) and calibration curve. The partial score was also constructed and stratified them into low, moderate and high-risk subgroups for death according to the tripartite grouping method. Multivariate Cox regression analysis and the propensity score matching method were respectively used to test the association between adjuvant chemotherapy and OS in different risk subgroups.

Results

Age, diameter, histological differentiation, lymph node metastasis, estrogen, and progesterone receptor were incorporated into the nomogram and validation results showed this nomogram was well-calibrated to predict the 3-year [AUC =74.1%; 95% confidence interval (CI): 70.1–78.0%] and 5-year overall survival [AUC =72.3%; 95% CI: 69.6–75.1%]. Adjuvant chemotherapy was negatively associated with death in high risk subgroup [Hazard Ratio (HR) = 0.54; 95% CI: 0.37–0.77; P<0.001]. However, no significant association were found in groups with low (HR=1.47; 95% CI: 0.52–4.19; P=0.47) and moderate risk (HR=0.78; 95% CI: 0.42–1.48; P=0.45). The 1:1 PSM generated 822 pairs of well-matched patients and Kaplan-Meier showed the high-risk patients could benefit from chemotherapy, whereas low risk and moderate risk subjects did not appear to benefit from chemotherapy.

Conclusion

Not all of the breast cancer patients benefit equally from chemotherapy. The nomogram could be used to evaluate the overall survival of breast cancer patients and predict the magnitude of benefit and guide adjuvant chemotherapy for breast cancer patients after surgery.

Examination of the Biomark assay as an alternative to Oncotype DX for defining chemotherapy benefit

Currently the 21-gene recurrence score (RS) assay called Oncotype DX is recommended by the National Comprehensive Cancer Network guideline for defining the benefit of chemotherapy. To overcome the cost disadvantages of the Oncotype DX assay and the turnaround time, a multigene assay was examined to compare the correlation of the RS and the predicted score (PS) of the present study. Paraffin-embedded tissues of 50 cases with early-stage estrogen receptor (ER)-positive breast cancer, who underwent the Oncotype DX test were used. A total of 149 candidate genes with high correlation to the RS were identified, in another project (Lee et al, unpublished data). Reverse transcription-quantitative polymerase chain reaction biomark assays were conducted using the dynamic array integrated fluidic circuit and the correlation analysis was performed with BRB ArrayTools. A predictive model was developed by the coefficient and gene expression, and 41 genes were identified. If the cut-off was ≥18, the predicted model was 18/50 cases, and the RS was 19, indicating that the differential rate of predicted response against RS was 2%. If the cutoff was ≥11, the predicted model was 38/50 cases and the RS was 34, indicating a difference of 8%. Genes common to the Oncotype DX and the Biomark assay include marker of proliferation Ki-67, aurora kinase A, Erb-B2 receptor tyrosine kinase 2, glutathione S-transferase Mu 1, estrogen receptor 1, progesterone receptor, B-cell lymphoma 2, signal peptide CUB domain EGF-like 2 and 5 reference genes. The remaining 28 genes are involved in various pathways and functions. This result indicates that there is a significant correlation between PS and RS scores, although validation of results is required to accurately determine the risk of distant recurrence. The Biomark assay is an easy and inexpensive way to measure mRNA expression. The present study demonstrates the possibility of the Biomark assay as an alternative for defining chemotherapy benefit in individual patients with ER-positive early-stage breast cancer.

Intra-tumor molecular heterogeneity in breast cancer: definitions of measures and association with distant recurrence-free survival

PURPOSE

The purpose of the study was to define quantitative measures of intra-tumor heterogeneity in breast cancer based on histopathology data gathered from multiple samples on individual patients and determine their association with distant recurrence-free survival (DRFS).

METHODS

We collected data from 971 invasive breast cancers, from 1st January 2000 to 23rd March 2014, that underwent repeat tumor sampling at our institution. We defined and calculated 31 measures of intra-tumor heterogeneity including ER, PR, and HER2 immunohistochemistry (IHC), proliferation, EGFR IHC, grade, and histology. For each heterogeneity measure, Cox proportional hazards models were used to determine whether patients with heterogeneous disease had different distant recurrence-free survival (DRFS) than those with homogeneous disease.

RESULTS

The presence of heterogeneity in ER percentage staining was prognostic of reduced DRFS with a hazard ratio of 4.26 (95% CI 2.22-8.18, p < 0.00002). It remained significant after controlling for the ER status itself (p < 0.00062) and for patients that had chemotherapy (p < 0.00032). Most of the heterogeneity measures did not show any association with DRFS despite the considerable sample size.

CONCLUSIONS

Intra-tumor heterogeneity of ER receptor status may be a predictor of patient DRFS. Histopathologic data from multiple tissue samples may offer a view of tumor heterogeneity and assess recurrence risk.

Clinicopathological Profile and Treatment Outcomes of Bilateral Breast Cancer: A Study from Tertiary Cancer Center in South India

Background: Bilateral breast cancer (BBC) is a rare clinical entity with limited data regarding clinicopathological aspects and treatment guidelines. Materials and Methods: This was an observational study of patients diagnosed with BBC from August 2012 to July 2014. Synchronous breast cancers (SBCs) was defined as two tumors diagnosed within an interval of 6 months and metachronous breast cancer (MBC) as second cancer diagnosed after 6 months. Results: Out of 750 breast cancer patients seen during a 2-year period, 35 had BBC. Ten patients were diagnosed as SBC whereas 25 patients as MBC. Among patients with MBC, the average time for development of contralateral breast cancer was 5 years. In 8 patients, the contralateral breast cancer was detected mammography whereas rest 27 patients were detected by clinical breast examination. At a median follow-up of 24 months, 23 (66%) patients were disease free, 9 (26%) patients had disease relapse, and 3 (8%) patients succumbed to the progressive disease. Conclusions: Every patient with breast cancer should be regularly followed up with clinical breast examination at a more frequent interval. The role of frequent clinical breast examination appears more than mammography especially beyond 5 years for early detection of contralateral breast cancer.

Current status of the prognostic molecular biomarkers in breast cancer: A systematic review

Biomarkers that facilitate the prediction of breast cancer prognosis can improve the quality of life in patients during the long period of illness and treatment. Particularly in recent years, with the advent of a more exhaustive analysis of genetic information and gene products, the molecular mechanisms at play during breast cancer have gradually become clearer. In the present study, a systematic review of the literature between 2009 and 2014 was conducted by searching for the keywords 'breast cancer', 'biomarkers', 'diagnosis', 'prognosis' and 'drug response' to clarify the present state of knowledge regarding biomarkers. In the final analysis, 16 studies on biomarkers for the breast cancer prognosis were retrieved. From these, 7 biomarkers in 9 studies were found to be strongly reliable predictors of prognosis and a further 7 biomarkers in 7 studies were poorly reliable. The use of these prognostic biomarkers should increase the options available for treatment algorithms.

ErbB-2 nuclear function in breast cancer growth, metastasis and resistance to therapy

Approximately 15-20% of breast cancers (BC) show either membrane overexpression of ErbB-2 (MErbB-2), a member of the ErbBs family of receptor tyrosine kinases, or ERBB2 gene amplification. Until the development of MErbB-2-targeted therapies, this BC subtype, called ErbB-2-positive, was associated with increased metastatic potential and poor prognosis. Although these therapies have significantly improved overall survival and cure rates, resistance to available drugs is still a major clinical issue. In its classical mechanism, MErbB-2 activates downstream signaling cascades, which transduce its effects in BC. The fact that ErbB-2 is also present in the nucleus of BC cells was discovered over twenty years ago. Also, compelling evidence revealed a non-canonical function of nuclear ErbB-2 as a transcriptional regulator. As a deeper understanding of nuclear ErbB-2 actions would be crucial to the disclosure of its role as a biomarker and a target of therapy in BC, we will here review its function in BC, in particular, its role in growth, metastatic spreading and response to currently available MErbB-2-positive BC therapies.

Melatonin Represses Metastasis in Her2-Postive Human Breast Cancer Cells by Suppressing RSK2 Expression

The importance of the circadian/melatonin signal in suppressing the metastatic progression of breast and other cancers has been reported by numerous laboratories including our own. Currently, the mechanisms underlying the antimetastatic actions of melatonin have not been well established. In the present study, the antimetastatic actions of melatonin were evaluated and compared on the ERα-negative, Her2-positive SKBR-3 breast tumor cell line and ERα-positive MCF-7 cells overexpressing a constitutively active HER2.1 construct (MCF-7Her2.1 cells). Activation of Her2 is reported to induce the expression and/or phosphorylation-dependent activation of numerous kinases and transcription factors that drive drug resistance and metastasis in breast cancer. A key signaling node activated by the Her2/Mapk/Erk pathway is Rsk2, which has been shown to induce numerous signaling pathways associated with the development of epithelial-to-mesenchymal transition (EMT) and metastasis including: Creb, Stat3, cSrc, Fak, Pax, Fascin, and actin polymerization. The data demonstrate that melatonin (both endogenous and exogenous) significantly represses this invasive/metastatic phenotype through a mechanism that involves the suppression of EMT, either by promoting mesenchymal-to-epithelial transition, and/or by inhibiting key signaling pathways involved in later stages of metastasis. These data, combined with our earlier in vitro studies, support the concept that maintenance of elevated and extended duration of nocturnal melatonin levels plays a critical role in repressing the metastatic progression of breast cancer.

IMPLICATIONS

Melatonin inhibition of Rsk2 represses the metastatic phenotype in breast cancer cells suppressing EMT or inhibiting other mechanisms that promote metastasis; disruption of the melatonin signal may promote metastatic progression in breast cancer. Mol Cancer Res; 14(11); 1159-69. ©2016 AACR.

Strategies in functional proteomics: Unveiling the pathways to precision oncology

Personalised strategies in cancer care are required to overcome the therapeutic challenges posed by variability between patients and disease subsets. To this end, enhanced precision tools must be developed to describe the molecular drivers of malignant proliferation. Such tools must also identify druggable targets and biomarkers in order to provide essential information regarding drug development and therapeutic outcome. Here we discuss how proteomics-based approaches provide a set of viable methodologies capable of delivering quantitative information throughout the main stages of personalised oncology and a ratiometric platform that delivers systems-wide methods for drug evaluation.

Stat3 regulates ErbB-2 expression and co-opts ErbB-2 nuclear function to induce miR-21 expression, PDCD4 downregulation and breast cancer metastasis

Membrane overexpression of the receptor tyrosine kinase ErbB-2 (MErbB-2) accounts for a clinically aggressive breast cancer (BC) subtype (ErbB-2-positive) with increased incidence of metastases. We and others demonstrated that nuclear ErbB-2 (NErbB-2) also plays a key role in BC and is a poor prognostic factor in ErbB-2-positive tumors. The signal transducer and activator of transcription 3 (Stat3), another player in BC, has been recognized as a downstream mediator of MErbB-2 action in BC metastasis. Here, we revealed an unanticipated novel direction of the ErbB-2 and Stat3 interaction underlying BC metastasis. We found that Stat3 binds to its response elements (GAS) at the ErbB-2 promoter to upregulate ErbB-2 transcription in metastatic, ErbB-2-positive BC. We validated these results in several BC subtypes displaying metastatic and non-metastatic ability, highlighting Stat3 general role as upstream regulator of ErbB-2 expression in BC. Moreover, we showed that Stat3 co-opts NErbB-2 function by recruiting ErbB-2 as its coactivator at the GAS sites in the promoter of microRNA-21 (miR-21), a metastasis-promoting microRNA (miRNA). Using an ErbB-2 nuclear localization domain mutant and a constitutively activated ErbB-2 variant, we found that NErbB-2 role as a Stat3 coactivator and also its direct role as transcription factor upregulate miR-21 in BC. This reveals a novel function of NErbB-2 as a regulator of miRNAs expression. Increased levels of miR-21, in turn, downregulate the expression of the metastasis-suppressor protein programmed cell death 4 (PDCD4), a validated miR-21 target. Using an in vivo model of metastatic ErbB-2-postive BC, in which we silenced Stat3 and reconstituted ErbB-2 or miR-21 expression, we showed that both are downstream mediators of Stat3-driven metastasis. Supporting the clinical relevance of our results, we found an inverse correlation between ErbB-2/Stat3 nuclear co-expression and PDCD4 expression in ErbB-2-positive primary invasive BCs. Our findings identify Stat3 and NErbB-2 as novel therapeutic targets to inhibit ErbB-2-positive BC metastasis.

Identifying patients at high risk of breast cancer recurrence: strategies to improve patient outcomes

Identifying patients at high risk of breast cancer recurrence has important implications not only for enabling the ability to provide accurate information to patients but also the potential to improve patient outcomes. Patients at high recurrence risk can be offered appropriate treatment to improve the overall survival. However, the major challenge is identifying patients with early-stage breast cancer at lower risk who may be spared potentially toxic therapy. The successful integration of molecular assays into clinical practice may address the problem of overtreatment and improve overall patient outcomes.

Targeting ErbB-2 nuclear localization and function inhibits breast cancer growth and overcomes trastuzumab resistance

Membrane overexpression of ErbB-2/HER2 receptor tyrosine kinase (membrane ErbB-2 (MErbB-2)) has a critical role in breast cancer (BC). We and others have also shown the role of nuclear ErbB-2 (NErbB-2) in BC, whose presence we identified as a poor prognostic factor in MErbB-2-positive tumors. Current anti-ErbB-2 therapies, as with the antibody trastuzumab (Ttzm), target only MErbB-2. Here, we found that blockade of NErbB-2 action abrogates growth of BC cells, sensitive and resistant to Ttzm, in a scenario in which ErbB-2, ErbB-3 and Akt are phosphorylated, and ErbB-2/ErbB-3 dimers are formed. Also, inhibition of NErbB-2 presence suppresses growth of a preclinical BC model resistant to Ttzm. We showed that at the cyclin D1 promoter, ErbB-2 assembles a transcriptional complex with Stat3 (signal transducer and activator of transcription 3) and ErbB-3, another member of the ErbB family, which reveals the first nuclear function of ErbB-2/ErbB-3 dimer. We identified NErbB-2 as the major proliferation driver in Ttzm-resistant BC, and demonstrated that Ttzm inability to disrupt the Stat3/ErbB-2/ErbB-3 complex underlies its failure to inhibit growth. Furthermore, our results in the clinic revealed that nuclear interaction between ErbB-2 and Stat3 correlates with poor overall survival in primary breast tumors. Our findings challenge the paradigm of anti-ErbB-2 drug design and highlight NErbB-2 as a novel target to overcome Ttzm resistance.

Effect of continuous statistically standardized measures of estrogen and progesterone receptors on disease-free survival in NCIC CTG MA.12 Trial and BC Cohort

INTRODUCTION

We hypothesized improved inter-laboratory comparability of estrogen receptor (ER) and progesterone receptor (PgR) across different assay methodologies with adjunctive statistical standardization, akin to bone mineral density (BMD) z-scores. We examined statistical standardization in MA.12, a placebo-controlled pre-menopausal trial of adjuvant tamoxifen with locally assessed hormone receptor +/- tumours, and in a cohort of post-menopausal British Columbia (BC) tamoxifen-treated patients.

METHODS

ER and PgR were centrally assessed for both patient groups with real time quantitative reverse transcription polymerase chain reaction (qPCR) and immunohistochemistry (IHC). Effects on disease-free survival (DFS) were investigated separately for 345 MA.12 and 673 BC patients who had both qPCR and IHC assessments. Comparisons utilized continuous laboratory units and statistically standardized z-scores. Univariate categorization of ER/PgR was by number of standard deviations (SD) above or below the mean (z-score ≥1.0 SD below mean; z-score <1.0 SD below mean; z-score ≤1.0 SD above mean; z-score >1.0 SD above mean). Exploratory multivariate examinations utilized step-wise Cox regression.

RESULTS

Median follow-up for MA.12 was 9.7 years; for BC patients, 11.8 years. For MA.12, 101 of 345 (29%) patients were IHC ER-PgR-. ER was not univariately associated with DFS (qPCR, P = 0.19; IHC, P = 0.08), while PgR was (qPCR, P = 0.09; IHC, P = 0.04). For BC patients, neither receptor was univariately associated with DFS: for ER, PCR, P = 0.36, IHC, P = 0.24; while for PgR, qPCR, P = 0.17, IHC, P = 0.31. Multivariately, MA.12 patients randomized to tamoxifen had significantly better DFS (P = 0.002 to 0.005) than placebo. Meanwhile, jointly ER and PgR were not associated with DFS whether assessed by qPCR or by IHC in all patients, or in the subgroup of patients with IHC positive stain, for pooled or separate treatment arms. Different results by type of continuous unit supported the concept of ER level being relevant for medical decision-making. For postmenopausal BC tamoxifen patients, higher qPCR PgR was weakly associated with better DFS (P = 0.06).

CONCLUSIONS

MA.12 pre-menopausal patients in a placebo-controlled tamoxifen trial had similar multivariate prognostic effects with statistically standardized hormone receptors when tumours were assayed by qPCR or IHC, for hormone receptor +/- and + tumours. The BC post-menopausal tamoxifen cohort did not exhibit a significant prognostic association of ER or PgR with DFS. Adjunctive statistical standardization is currently under investigation in other NCIC CTG endocrine trials.

How many etiological subtypes of breast cancer: two, three, four, or more?

Breast cancer is a heterogeneous disease, divisible into a variable number of clinical subtypes. A fundamental question is how many etiological classes underlie the clinical spectrum of breast cancer? An etiological subtype reflects a grouping with a common set of causes, whereas a clinical subtype represents a grouping with similar prognosis and/or prediction. Herein, we review the evidence for breast cancer etiological heterogeneity. We then evaluate the etiological evidence with mRNA profiling data. A bimodal age distribution at diagnosis with peak frequencies near ages 50 and 70 years is a fundamental characteristic of breast cancer for important tumor features, clinical characteristics, risk factor profiles, and molecular subtypes. The bimodal peak frequencies at diagnosis divide breast cancer overall into a "mixture" of two main components in varying proportions in different cancer populations. The first breast cancer tends to arise early in life with modal age-at-diagnosis near 50 years and generally behaves aggressively. The second breast cancer occurs later in life with modal age near 70 years and usually portends a more indolent clinical course. These epidemiological and molecular data are consistent with a two-component mixture model and compatible with a hierarchal view of breast cancers arising from two main cell types of origin. Notwithstanding the potential added value of more detailed categorizations for personalized breast cancer treatment, we suggest that the development of better criteria to identify the two proposed etiologic classes would advance breast cancer research and prevention.

Gelatinase B (-1562C/T) polymorphism in tumor progression and invasion of breast cancer

Matrix metalloproteinases (MMPs) play an important role in breast cancer tumor invasion and progression. MMP-9 is a member of the MMP family and is also known as Gelatinase B or type IV collagenases (92 kDa) and possesses proteolytic activity against type IV collagen, a major component of the basement membrane. Our study aims to examine the association of Gelatinase B (-1562C > T) promoter polymorphism with breast cancer invasion and progression. The study involves 200 breast cancer patients and age-matched 191 healthy controls. The SNP-1562C > T (rs3918242) in MMP-9 promoter region was examined by allele-specific polymerase chain reaction and gel electrophoresis. The genotypes were determined and compared between patients and controls, and the influence of the polymorphism on clinicopathological data was analyzed. The T allele of the -1562C > T MMP-9 polymorphism was detected more frequently in breast cancer patients than controls (p < 0.001). Our results suggest the clinical importance of MMP-9 gene polymorphism (-1562C > T) in breast cancer patients. The study may also help in identifying individuals at risk of developing breast cancer.

Immunohistochemical study of Aquaporin-1, Cyclooxygenase-2 and Apoptosis Protease-Activating Factor-1 expression in breast cancers. Preliminary study

The aim of the present study is to establish possible associations between Aquaporin-1, Cyclooxygenase-2 and Apoptosis Protease-Activating Factor-1 expression in breast cancers and pathological and immunohistochemical characteristics of the examined tumors.

For the purpose of this study we used paraffin embedded archived tumor material of 31 breast cancer patients from the Pathology Department of the Odorheiu Secuiesc Municipal Hospital. We performed immunohistochemistry reactions ER, PR, HER2, AQP1, COX2 and APAF1, and following independent evaluation by two pathologists the obtained data was statistically analyzed. The tumors were divided into three groups based on their histological properties, and correlations were made with the examined markers.

AQP1, COX2 and APAF1 immunostaining results produced significant correlations with HER2 status and histological groups. There were no statistical correlations between ER or PR status and the three examined markers.

Lobular carcinomas showed AQP1 and COX2 overexpression, and loss of APAF1 expression, which all correlated with HER2 negative status.

We concluded that AQP1 could be a useful marker for detecting more aggressive subtypes and also for evaluating tumor angiogenesis. COX2 and APAF1 immunoexpression, although somewhat specific to certain histological groups, needs to be further characterized in order to be a useful marker for the clinical setting.

Predictive tests for individualization of pharmacological cancer treatment

BACKGROUND

The selection of cancer drugs for an individual patient is still based mostly on cancer type and stage. Predictive tests are needed to make individualized and more efficient pharmacological cancer treatment possible.

OBJECTIVE

To provide an overview of available, possible future development and principles for development of predictive tests for individualized selection of cancer drugs.

METHODS

Overview of published data.

RESULTS/CONCLUSION

Despite increased knowledge in cancer biology, only limited progress has been made in the development and use of predictive tests. However, rapid progress in this field will be possible using already available and emerging technologies, but requires a paradigm shift in principles for the development and use of cancer drugs. Assessment of drug activity in intact tumor cells and tumor cell gene expression signatures are considered to have greatest potential for the development of versatile predictive tests.

Lymphatic and Capillary Invasion Patterns in Triple Negative Breast Cancer

Triple negative breast cancer (TNBC) comprises approximately 15 to 20 per cent of all breast cancer cases. Many studies have detected less lymph node metastasis in TNBC than sporadic breast cancers. In this study, we studied capillary and lymphatic invasion in tumors of patients with TNBC. To differentiate the capillary invasion and lymphovascular invasion. We used the Anti-human CD34 and antihuman D2-40 antibodies. Antihuman CD34 antibodies stain the blood vessels and lymphatics. However, antihuman D2-40 antibodies stain lymphatics specifically. Two experienced pathologists blinded to clinical data evaluated capillary and lymphatic invasion existence in 39 TNBC patients’ tumor samples. Tumor samples were immunohistochemically stained with CD34 (endothelial cell marker) and D2–40 (podoplanin, a membrane protein, specific for lymphatic endothelium). The CD34-positive samples were categorized into two groups depending on their reaction with D2-40: lymphatic (D2-40-positive) and capillary (D2-40-negative) invasion. We have detected vascular invasion in 15 of 39 samples (38.5%) with CD34. Among those, capillary invasion was found in 14 (35.9%) and lymphatic invasion in three (7.7%) and both in two (5.1%) tumors. We did not find any significant correlation among capillary invasion, lymphatic invasion, vascular invasion, tumor grade, menopause status, history of cancer, and TNM. Capillary invasion is more commonly observed than lymphatic invasion in patients with TNBC. This finding supports the fact that more hematogenous metastasis (spreading) and less lymph node metastasis are seen in patients with TNBC.

Cost-effectiveness of a 21-gene recurrence score assay versus Canadian clinical practice in women with early-stage estrogen- or progesterone-receptor-positive, axillary lymph-node negative breast cancer

BACKGROUND

A 21-gene recurrence score (RS) assay may inform adjuvant systematic treatment decisions in women with early stage breast cancer. We sought to investigate the cost effectiveness of using the RS-assay versus current clinical practice (CCP) in women with early-stage estrogen- or progesterone-receptor-positive, axilliary lymph-node negative breast cancer (ER+/ PR + LN- ESBC) from the perspective of the Canadian public healthcare system.

METHODS

We developed a Markov model to project the lifetime clinical and economic consequences of ESBC. We evaluated adjuvant therapy separately in post- and pre-menopausal women with ER+/ PR + LN- ESBC. We assumed that the RS-assay would reclassify pre- and post-menopausal women among risk levels (low, intermediate and high) and guide adjuvant systematic treatment decisions. The model was parameterized using 7 year follow up data from the Manitoba Cancer Registry, cost data from Manitoba administrative databases, and secondary sources. Costs are presented in 2010 CAD. Future costs and benefits were discounted at 5%.

RESULTS

The RS-assay compared to CCP generated cost-savings in pre-menopausal women and had an ICER of $60,000 per QALY gained in post-menopausal women. The cost effectiveness was most sensitive to the proportion of women classified as intermediate risk by the RS-assay who receive adjuvant chemotherapy and the risk of relapse in the RS-assay model.

CONCLUSIONS

The RS-assay is likely to be cost effective in the Canadian healthcare system and should be considered for adoption in women with ER+/ PR + LN- ESBC. However, ongoing assessment and validation of the assay in real-world clinical practice is warranted.

A pathway-based classification of breast cancer integrating data on differentially expressed genes, copy number variations and microRNA target genes

Breast cancer is a clinically heterogeneous disease characterized by distinct molecular aberrations. Understanding the heterogeneity and identifying subgroups of breast cancer are essential to improving diagnoses and predicting therapeutic responses. In this paper, we propose a classification scheme for breast cancer which integrates data on differentially expressed genes (DEGs), copy number variations (CNVs) and microRNAs (miRNAs)-regulated mRNAs. Pathway information based on the estimation of molecular pathway activity is also applied as a postprocessor to optimize the classifier. A total of 250 malignant breast tumors were analyzed by k-means clustering based on the patterns of the expression profiles of 215 intrinsic genes, and the classification performances were compared with existing breast cancer classifiers including the BluePrint and the 625-gene classifier. We show that a classification scheme which incorporates pathway information with various genetic variations achieves better performance than classifiers based on the expression levels of individual genes, and propose that the identified signature serves as a basic tool for identifying rational therapeutic opportunities for breast cancer patients.

A logistic regression model for predicting axillary lymph node metastases in early breast carcinoma patients

Nodal staging in breast cancer is a key predictor of prognosis. This paper presents the results of potential clinicopathological predictors of axillary lymph node involvement and develops an efficient prediction model to assist in predicting axillary lymph node metastases. Seventy patients with primary early breast cancer who underwent axillary dissection were evaluated. Univariate and multivariate logistic regression were performed to evaluate the association between clinicopathological factors and lymph node metastatic status. A logistic regression predictive model was built from 50 randomly selected patients; the model was also applied to the remaining 20 patients to assess its validity. Univariate analysis showed a significant relationship between lymph node involvement and absence of nm-23 (p = 0.010) and Kiss-1 (p = 0.001) expression. Absence of Kiss-1 remained significantly associated with positive axillary node status in the multivariate analysis (p = 0.018). Seven clinicopathological factors were involved in the multivariate logistic regression model: menopausal status, tumor size, ER, PR, HER2, nm-23 and Kiss-1. The model was accurate and discriminating, with an area under the receiver operating characteristic curve of 0.702 when applied to the validation group. Moreover, there is a need discover more specific candidate proteins and molecular biology tools to select more variables which should improve predictive accuracy.

Predictive immunohistochemical biomarkers in the context of neoadjuvant therapy for breast cancer

The adoption of personalized medicine has led to the search for prognostic and predictive markers that can be applied to individual patients to give optimal information for their clinical management. We have used samples from randomized clinical trials of hormonal and chemotherapy to identify relevant markers of sensitivity and resistance using a neoadjuvant approach by linking expression of a panel of proteins involved in growth factor receptor signaling, angiogenesis, estrogen receptor signaling, and hypoxia to individual patient response. We evaluated samples from randomized clinical trials of epirubicin with or without tamoxifen, and letrozole with or without metronomic cyclophosphamide, to study chemotherapy, hormonal therapy, and antiangiogenic effects. We present a proof of principle of this approach in identifying several key pathways that are associated with clinical and pathological response. Thus, we have shown that the hypoxia-inducible factor (HIF) pathway, mitogen activated protein kinase, and phosphorylated estrogen receptor-α can identify patients who are likely to respond to hormonal therapy and that HIF signaling is also a marker of resistance for anthracycline-based chemotherapy. To redress the role of HIF, we then evaluated samples from a randomized control trial of an anthracycline chemotherapy with and without erythropoietin. These studies demonstrate that the approach of using primary systemic therapy in breast can identify markers of response and potentially targets for rationale design of new therapies.

Predictive biomarkers in colorectal cancer: usage, validation, and design in clinical trials

As cancer treatment development has shifted its attention to targeted therapies, it is becoming increasingly important to provide tools for selecting the right treatment for an individual patient to achieve optimal clinical benefit. Biomarkers, identified and studied in the process of understanding the nature of the disease at the molecular pathogenesis level, have been increasingly recognized as a critical aspect in more accurate diagnosis, prognosis assessment, and therapeutic targeting. Predictive biomarkers, which can aid treatment decisions, require extensive data for validation. In this article, we discuss the definition, clinical usages, and more extensively the clinical trial designs for the validation of predictive biomarkers. Predictive biomarker validation methods can be broadly grouped into retrospective and prospective designs. Retrospective validation utilizes data from previously conducted prospective randomized controlled trials. Prospective designs include enrichment designs, treatment-by-marker interaction designs, marker-based strategy designs, and adaptive designs. We discuss each design with examples and provide comparisons of the advantages and disadvantages among the different designs. We conclude that the combination of scientific, clinical, statistical, ethical, and practical considerations provides guidance for the choice of the clinical trial design for validation of each proposed predictive biomarker.

Clinical relevance of ErbB-2/HER2 nuclear expression in breast cancer

Background

The biological relevance of nuclear ErbB-2/HER2 (NuclErbB-2) presence in breast tumors remains unexplored. In this study we assessed the clinical significance of ErbB-2 nuclear localization in primary invasive breast cancer. The reporting recommendations for tumor marker prognostic studies (REMARK) guidelines were used as reference.

Methods

Tissue microarrays from a cohort of 273 primary invasive breast carcinomas from women living in Chile, a Latin American country, were examined for membrane (MembErbB-2) and NuclErbB-2 expression by an immunofluorescence (IF) protocol we developed. ErbB-2 expression was also evaluated by immunohistochemistry (IHC) with a series of antibodies. Correlation between NuclErbB-2 and MembErbB-2, and between NuclErbB-2 and clinicopathological characteristics of tumors was studied. The prognostic value of NuclErbB-2 in overall survival (OS) was evaluated using Kaplan-Meier method, and Cox model was used to explore NuclErbB-2 as independent prognostic factor for OS.

Results

The IF protocol we developed showed significantly higher sensitivity for detection of NuclErbB-2 than IHC procedures, while its specificity and sensitivity to detect MembErbB-2 were comparable to those of IHC procedures. We found 33.6% NuclErbB-2 positivity, 14.2% MembErbB-2 overexpression by IF, and 13.0% MembErbB-2 prevalence by IHC in our cohort. We identified NuclErbB-2 positivity as a significant independent predictor of worse OS in patients with MembErbB-2 overexpression. NuclErbB-2 was also a biomarker of lower OS in tumors that overexpress MembErbB-2 and lack steroid hormone receptors.

Conclusions

We revealed a novel role for NuclErbB-2 as an independent prognostic factor of poor clinical outcome in MembErbB-2-positive breast tumors. Our work indicates that patients presenting NuclErbB-2 may need new therapeutic strategies involving specific blockage of ErbB-2 nuclear migration.

Relationships between serum HER2 ECD, TIMP-1 and clinical outcomes in Taiwanese breast cancer

BACKGROUND

Serum levels of the extracellular domain of HER2/neu (HER2 ECD) have been demonstrated to be associated with clinical outcomes. A disintegrin and metalloproteinase-10, a sheddase of HER2/neu, can drive cancer progression and its activity is inhibited by tissue inhibitor of metalloproteinase-1 (TIMP-1). However, elevated TIMP-1 expression has been associated with a poor prognosis of breast cancer. Therefore, this study was performed to explore the relationships between serum HER2 ECD, TIMP-1 and clinical outcomes.

METHODS

One hundred and eighty-five female breast cancer patients, who received curative mastectomy without neo-adjuvant chemotherapy at Chang-Gung Memorial Hospital, were recruited with informed consent for this study. Pre-operative serum levels of HER2 ECD and TIMP-1 were measured using an enzyme-linked immunosorbent assay.

RESULTS

Twenty-three cases (12.4%) were classified HER2 ECD positive. HER2 ECD positivity was significantly associated with age, lymph node involvement, histological grade, estrogen receptor status, progesterone receptor status, tissue HER2/neu overexpression, and disease-free survival (DFS). In an age, stage, ER and HER2/neu status matched subgroup (N = 41), the serum level of TIMP-1 was significantly associated with HER2 ECD positivity and DFS.

CONCLUSIONS

A high serum TIMP-1 was significantly associated with HER2 ECD positivity and a poorer DFS among Taiwanese primary breast cancer patients with HER2 overexpression.

Incidence of breast cancer in the United States: current and future trends

BACKGROUND

The incidence of breast cancer increased in the United States until circa 2000 then decreased, mostly among women with estrogen receptor (ER)-positive cancers. Time trends provide important clues for cancer etiology and prevention; however, the observed trends of ER-positive and ER-negative breast cancers can be biased by missing ER data.

METHODS

We developed a simple imputation method to correct invasive female breast cancer incidence for missing or unknown ER expression, using nationally representative data from the National Cancer Institute's Surveillance, Epidemiology, and End Results Program during 1980-2008, including 588,720 invasive female breast cancer patients with 471,336,233 woman-years of follow-up. Corrected rates of ER-positive and ER-negative breast cancers were used to calculate age-standardized incidence rates, estimated annual percentage changes, and projections derived from age-period-cohort models.

RESULTS

The recent decrease in the incidence of breast cancer overall stabilized near 200 per 100,000 woman-years by 2007-2008, reflecting a transient decrease in ER-positive cancers and a steady decrease in ER-negative cancers. The projected incidence rate for breast cancer overall through the year 2016 was similar to the incidence rate during 2007-2008. In contrast, rates of ER-positive breast cancers were projected to increase 5.3% (95% confidence interval = 5.2% to 5.4%), whereas rates of ER-negative breast cancers were projected to decrease 11.4% (95% confidence interval = 11.3% to 11.6%) during 2009-2016.

CONCLUSION

Recent changes in breast cancer incidence overall reflect the superimposition of divergent trends in ER-positive and ER-negative cancers. If current trends continue, the incidence of ER-positive breast cancers will increase, the incidence of ER-negative breast cancers will continue to decrease, and the incidence of breast cancer overall will remain similar to its current level.

Effect of very small tumor size on cancer-specific mortality in node-positive breast cancer

PURPOSE

Traditionally, larger tumor size and increasing lymph node (LN) involvement have been considered independent predictors of increased breast cancer-specific mortality (BCSM). We sought to characterize the interaction between tumor size and LN involvement in determination of BCSM. In particular, we evaluated whether very small tumor size may predict for increased BCSM relative to larger tumors in patients with extensive LN involvement.

PATIENTS AND METHODS

Using Surveillance, Epidemiology and End Results registry data, we identified 50,949 female patients diagnosed between 1990 and 2002 with nonmetastatic T1/T2 invasive breast cancer treated with surgery and axillary LN dissection. Primary study variables were tumor size, degree of LN involvement, and their corresponding interaction term. Kaplan-Meier methods, adjusted Cox proportional hazards models with interaction terms, and a linear trend test across nodal categories were performed.

RESULTS

Median follow-up was 99 months. In multivariable analysis, there was significant interaction between tumor size and LN involvement (P < .001). Using T1aN0 as reference, T1aN2+ conferred significantly higher BCSM compared with T1bN2+ (hazard ratio [HR], 20.66 v 12.53; P = .02). A similar pattern was seen among estrogen receptor (ER) -negative patients with T1aN2+ compared with T1bN2+ (HR, 24.16 v 12.67; P = .03), but not ER-positive patients (P = .52). The effect of very small tumor size on BCSM was intermediate among N1 cancers, between that of N0 and N2+ cancers.

CONCLUSION

Very small tumors with four positive LNs may predict for higher BCSM compared with larger tumors. In extensive node-positive disease, very small tumor size may be a surrogate for biologically aggressive disease. These results should be validated in future database studies.

Long-term prognostic role of functional limitations among women with breast cancer

BACKGROUND

The long-term prognostic role of functional limitations among women with breast cancer is poorly understood.

METHODS

We studied a cohort of 2202 women with breast cancer at two sites in the United States, who provided complete information on body functions involving endurance, strength, muscular range of motion, and small muscle dexterity following initial adjuvant treatment. Associations of baseline functional limitations with survival were evaluated in delayed entry Cox proportional hazards models, with adjustment for baseline sociodemographic factors, body mass index, smoking, physical activity, comorbidity, tumor characteristics, and treatment. Difference in covariates between women with and without limitations was assessed with Pearson χ(2) and Student t tests. All statistical tests were two-sided.

RESULTS

During the median follow-up of 9 years, 112 deaths were attributable to competing causes (5% of the cohort) and 157 were attributable to breast cancer causes (7% of the cohort). At least one functional limitation was present in 39% of study participants. Proportionately, more breast cancer patients with functional limitations after initial adjuvant treatment were older, less educated, and obese (P < .001). In multivariable models, functional limitations were associated with a statistically significantly increased risk of death from all causes (hazard ratio [HR] = 1.40, 95% confidence interval [CI] = 1.03 to 1.92) and from competing causes (HR = 2.60, 95% CI = 1.69 to 3.98) but not from breast cancer (HR = 0.90, 95% CI = 0.64 to 1.26). The relationship between functional limitations and overall survival differed by tumor stage (among women with stage I and stage III breast cancer, HR = 2.02, 95% CI = 1.23 to 3.32 and HR = 0.74, 95% CI = 0.42 to 1.30, respectively).

CONCLUSION

In this prospective cohort study, functional limitations following initial breast cancer treatment were associated with an important reduction in all-cause and competing-cause survival, irrespective of clinical, lifestyle, and sociodemographic factors.

Lapatinib plus capecitabine in women with HER-2-positive advanced breast cancer: final survival analysis of a phase III randomized trial

OBJECTIVES

A planned interim analysis of study EGF100151 prompted early termination of enrollment based on a longer time to progression with lapatinib and capecitabine than with capecitabine alone in patients with human epidermal growth factor receptor (HER)-2(+) previously treated advanced breast cancer or metastatic breast cancer (MBC). Here, we report final analyses of overall survival.

PATIENTS AND METHODS

Women with HER-2(+) MBC who progressed after regimens that included, but were not limited to, anthracyclines, taxanes, and trastuzumab, were randomized to lapatinib (1,250 mg/day) plus capecitabine (2,000 mg/m(2)) or capecitabine monotherapy (2,500 mg/m(2)) on days 1-14 of a 21-day cycle.

RESULTS

At enrollment termination, 399 patients were randomized, and nine were being screened and were offered combination treatment. In total, 207 and 201 patients were enrolled to combination therapy and monotherapy, respectively. Thirty-six patients receiving monotherapy crossed over to combination therapy following enrollment termination. The median overall survival times were 75.0 weeks for the combination arm and 64.7 weeks for the monotherapy arm (hazard ratio [HR], 0.87; 95% confidence interval [CI], 0.71-1.08; p = .210). A Cox regression analysis considering crossover as a time-dependent covariate suggested a 20% lower risk for death for patients treated with combination therapy (HR, 0.80; 95% CI, 0.64-0.99; p = .043). The low incidence of serious adverse events was consistent with previously reported rates.

CONCLUSIONS

Although premature enrollment termination and subsequent crossover resulted in insufficient power to detect differences in overall survival, exploratory analyses demonstrate a trend toward a survival advantage with lapatinib plus capecitabine. These data continue to support the efficacy of lapatinib in patients with HER-2(+) MBC.

Combined Src and ER blockade impairs human breast cancer proliferation in vitro and in vivo

Antiestrogen therapies arrest susceptible estrogen receptor (ER)-positive breast cancers by increasing p27. Since Src phosphorylates p27 to promote p27 proteolysis, Src activation observed in up to 40% of ER-positive cancers may contribute to antiestrogen resistance. In this article, we show that treatment with the Src-inhibitor saracatinib (AZD0530) together with ER-blocking drugs increased breast cancer cell cycle arrest via p27. Saracatinib and fulvestrant together more effectively increased p27, reduced Ki67, and impaired MDA-MB-361 xenograft tumor growth in vivo than either of the drugs alone. In contrast, saracatinib monotherapy rapidly gave rise to drug resistance. Since combined ER and Src inhibition delays development of resistance in vivo, these data support further clinical investigation of saracatinib in combination with fulvestrant for women with ER-positive breast cancer. Proteomic analysis revealed striking bypass activation of the mTOR pathway in saracatinib-resistant tumors. mTORC1 activation also arose following long-term culture of ER-positive breast cancer lines in the presence of saracatinib. These data indicate the utility of proteomic analysis of drug-resistant tumors to identify potential means of drug resistance. The use of mTOR kinase inhibitors with saracatinib may subvert drug resistance and prove to be more effective than saracatinib alone.

Inferring predominant pathways in cellular models of breast cancer using limited sample proteomic profiling

Background

Molecularly targeted drugs inhibit aberrant signaling within oncogenic pathways. Identifying the predominant pathways at work within a tumor is a key step towards tailoring therapies to the patient. Clinical samples pose significant challenges for proteomic profiling, an attractive approach for identifying predominant pathways. The objective of this study was to determine if information obtained from a limited sample (i.e., a single gel replicate) can provide insight into the predominant pathways in two well-characterized breast cancer models.

Methods

A comparative proteomic analysis of total cell lysates was obtained from two cellular models of breast cancer, BT474 (HER2+/ER+) and SKBR3 (HER2+/ER-), using two-dimensional electrophoresis and MALDI-TOF mass spectrometry. Protein interaction networks and canonical pathways were extracted from the Ingenuity Pathway Knowledgebase (IPK) based on association with the observed pattern of differentially expressed proteins.

Results

Of the 304 spots that were picked, 167 protein spots were identified. A threshold of 1.5-fold was used to select 62 proteins used in the analysis. IPK analysis suggested that metabolic pathways were highly associated with protein expression in SKBR3 cells while cell motility pathways were highly associated with BT474 cells. Inferred protein networks were confirmed by observing an up-regulation of IGF-1R and profilin in BT474 and up-regulation of Ras and enolase in SKBR3 using western blot.

Conclusion

When interpreted in the context of prior information, our results suggest that the overall patterns of differential protein expression obtained from limited samples can still aid in clinical decision making by providing an estimate of the predominant pathways that underpin cellular phenotype.