Basal-like phenotype is not associated with patient survival in estrogen-receptor-negative breast cancers

The Prediction Analysis of Microarray 50 (PAM50) Gene Expression Classifier Utilized in Indeterminate-Risk Breast Cancer Patients in Hungary: A Consecutive 5-Year Experience

BACKGROUND

Breast cancer has been categorized into molecular subtypes using immunohistochemical staining (IHC) and fluorescence in situ hybridization (FISH) since the early 2000s. However, recent research suggests that gene expression testing, specifically Prosigna® Prediction Analysis of Microarray 50 (PAM50), provides more accurate classification methods. In this retrospective study, we compared the results of IHC/FISH and PAM50 testing. We also examined the impact of various PAM50 parameters on overall survival (OS) and progression-free survival (PFS).

RESULTS

We analyzed 42 unilateral breast cancer samples, with 18 classified as luminal A, 10 as luminal B, 8 as Human epidermal growth factor receptor 2 (HER2)-positive, and 6 as basal-like using PAM50. Interestingly, 17 out of the 42 samples (40.47%) showed discordant results between histopathological assessment and the PAM50 classifier. While routine IHC/FISH resulted in classification differences for a quarter to a third of samples within each subtype, all basal-like tumors were misclassified. Hormone receptor-positive tumors (hazard rate: 8.7803; p = 0.0085) and patients who had higher 10-year recurrence risk scores (hazard rate: 1.0539; p = 0.0201) had shorter OS and PFS.

CONCLUSIONS

Our study supports the existing understanding of molecular subtypes in breast cancer and emphasizes the overlap between clinical characteristics and molecular subtyping. These findings underscore the value of gene expression profiling, such as PAM50, in improving treatment decisions for breast cancer patients.

The Clinicopathological Significance of Basal Markers in Early-Stage Invasive Carcinoma of No Special Type of the Breast

OBJECTIVE

Basal markers [cytokeratin 5/6 (CK5/6) and epidermal growth factor receptor (EGFR)] are used in identifying the basal-like breast carcinoma subtype, which is associated with a poor prognosis. However, the clinicopathological significance in early-stage invasive carcinoma of no special type (IC, NST) has not been well established.

MATERIAL AND METHOD

In a five-year period, 133 female patients with early-stage IC, NST with a median follow-up time of 89 months were included. The immunohistochemistry-based molecular subtypes were identified according to ASCO/CAP guidelines in 2013. The cutoff values for basal positivity were determined as 10% for each marker.

RESULTS

Basal positivity was recorded in 83.3% (5/6) of triple-negative breast cancers, 50% (2/4) of HER2-enriched, 18.6% (13/70) of luminal B, and 8.3% of luminal A (4/48) subtype. CK5/6 and EGFR positivity were significantly associated with ER negativity (p < 0.001). EGFR positive cases were significantly associated with PR negativity and HER2 positivity compared to negative cases. However, basal positivity was not associated with the patient outcome (p = 0.006 and p = 0.004, respectively).

CONCLUSION

Basal positive IC, NSTs were associated with hormone receptor negativity and HER2 overexpression; these patients would therefore be less likely to respond to hormonotherapy and more likely to benefit from anti-HER2 treatment as well as dual-kinase inhibitors. The lack of standardization of the definition of basal marker positivity may contribute to the conflicting results of prognostic studies. Hence, further studies focusing on developing a standard protocol for determining basal marker positivity are needed not only for IC, NST but also for other histological types of breast cancer.

Novel dynamics of human mucociliary differentiation revealed by single-cell RNA sequencing of nasal epithelial cultures

The upper airway epithelium, which is mainly composed of multiciliated, goblet, club and basal cells, ensures proper mucociliary function and can regenerate in response to assaults. In chronic airway diseases, defective repair leads to tissue remodeling. Delineating key drivers of differentiation dynamics can help understand how normal or pathological regeneration occurs. Using single-cell transcriptomics and lineage inference, we have unraveled trajectories from basal to luminal cells, providing novel markers for specific populations. We report that: (1) a precursor subgroup of multiciliated cells, which we have entitled deuterosomal cells, is defined by specific markers, such as DEUP1, FOXN4, YPEL1, HES6 and CDC20B; (2) goblet cells can be precursors of multiciliated cells, thus explaining the presence of hybrid cells that co-express markers of goblet and multiciliated cells; and (3) a repertoire of molecules involved in the regeneration process, such as keratins or components of the Notch, Wnt or BMP/TGFβ pathways, can be identified. Confirmation of our results on fresh human and pig airway samples, and on mouse tracheal cells, extend and confirm our conclusions regarding the molecular and cellular choreography at work during mucociliary epithelial differentiation.

Platinum Salts in Patients with Breast Cancer: A Focus on Predictive Factors

Breast cancer (BC) is the most frequent oncologic cause of death among women and the improvement of its treatments is compelling. Platinum salts (e.g., carboplatin, cisplatin, and oxaliplatin) are old drugs still used to treat BC, especially the triple-negative subgroup. However, only a subset of patients see a concrete benefit from these drugs, raising the question of how to select them properly. Therefore, predictive biomarkers for platinum salts in BC still represent an unmet clinical need. Here, we review clinical and preclinical works in order to summarize the current evidence about predictive or putative platinum salt biomarkers in BC. The association between BRCA1/2 gene mutations and platinum sensitivity has been largely described. However, beyond the mutations of these two genes, several other proteins belonging to the homologous recombination pathways have been linked to platinum response, defining the concept of BRCAness. Several works, here reviewed, have tried to capture BRCAness through different strategies, such as homologous recombination deficiency (HRD) score and genetic signatures. Moreover, p53 and its family members (p63 and p73) might also be used as predictors of platinum response. Finally, we describe the mounting preclinical evidence regarding base excision repair deficiency as a possible new platinum biomarker.

Triple-Negative Breast Cancer: A Comprehensive Study of Clinical, Histomorphological, and Immunohistochemical Features in Indian Patients

Triple-negative breast cancers (TNBCs) are characterized by negative expression for estrogen (ER), progesterone (PR), and human epidermal growth factor 2 (HER2) receptors. Although the majority of basal-like breast cancers (BLBCs) diagnosed based on gene expression profiling belong to the TNBC group, both entities are not synonymous. Core BLBCs are TNBCs, which are positive for basal cytokeratin (CK) and/or epidermal growth factor receptor (EGFR). We aimed to study and correlate a TNBC cohort for various histomorphological features and immunohistochemical (IHC) profile in Indian patients. We studied 205 naïve TNBCs for histopathological features, which were further evaluated for basal CKs-namely, CK5/6, CK14, CK17-and EGFR expression to classify them as core BLBCs, using criteria of any basal CK and/or EGFR positivity and 7-negative phenotype (7NP). Among 205 TNBCs, 91% of cases were core BLBCs, and absence of ductal carcinoma in situ (DCIS) was significantly associated ( P = .014) with core BLBC. Geographic necrosis was correlated with expression of CK17 ( P = .002) and EGFR ( P = .038). A ribbon-like trabecular pattern and absence of DCIS were associated with CK17 ( P = .0002 and P = .043, respectively) and CK14 ( P = .04 and P = .0008, respectively). TNBC is a heterogeneous subgroup with adverse clinicopathological features, and many of them show significant correlation with basal CKs. TNBCs cannot be classified as core BLBC or 7NP based on morphological features, except absence of DCIS. However, this study illustrates the heterogeneity in TNBCs on the basis of IHC markers.

Do platinum salts fit all triple negative breast cancers?

Triple-negative breast cancer (TNBC) is an aggressive disease with limited treatment options and poor prognosis once metastatic. Pre-clinical and clinical data suggest that TNBC could be more sensitive to platinum-based chemotherapy, especially among BRCA1/2-mutated patients. In recent years, several randomised trials have been conducted to evaluate platinum efficacy in both early-stage and advanced TNBC, with conflicting results especially for long-term outcomes. Experimental studies are now focusing on identifying biomarkers of response to help selecting patients who may benefit most from platinum-based therapies, including BRCA1/2 mutational status and genomic instability signatures (such as HRD-LOH or HRD-LST scores). A standard therapy for TNBC is still missing and platinum-based regimens represent an emerging therapeutic option for selected patients with a defect in the homologous recombination repair system. The identification of these patients through validated biomarker assays will be crucial to optimize the use of currently approved agents in TNBC.

c-Met and ERβ expression differences in basal-like and non-basal-like triple-negative breast cancer

Basal-like breast cancer (BLBC) and triple-negative breast cancer (TNBC) are two entities of breast cancer that share similar poor prognosis. Even though both cancers have overlaps, there are still some differences between those two types. It has been reported that the c-Met high expression was associated with poor prognosis not only in breast cancer but also in many other cancers. The role of ERβ in pathogenesis and treatment of breast cancer has remained controversial. In this study, we firstly distinguished basal-like from nonbasal-like cancer patients in TNBC patients using CK5/6 and EGFR as markers and next determined the relationship of basal-like breast cancer with c-Met or ERβ expression levels and prognosis in TNBC patients. One hundred twenty-seven patients who had been diagnosed with TNBC were enrolled. The clinical and pathological characteristics of the patients were recorded. The expression of EGFR, CK5/6, ERβ, and c-Met were evaluated with immunohistochemical methods using paraffin blocks. The median age of patients was 50.7 years. CK5/6 immunopositivity was 31.5 % (40/127), and EGFR was 40.2 % (51/127). Of the TNBC cases, 55.1 % (71/127) were positive for either CK5/6 or EGFR and were thus classified as basal-like breast cancer. C-Met (P < 0.001) and ERβ (P = 0.002) overexpression, small tumor sizes, a ductal subtype, and high-grade tumor were significantly correlated with BLBC. High c-Met expression was detected in 43.3 % patients. Metastatic lymph nodes and tumor size (>5 cm), which were both important prognostic predictors, were significantly associated with recurrence and mortality. BLBC typically demonstrates a unique profile. CK5/6 and EGFR expression combination indicates a higher basal-like phenotype possibility. The expression of c-Met and ERβ were significantly related to the basal-like phenotype. The classical markers, lymph node metastasis, and tumor size were found to have important prognostic value. However, high c-Met expression and basal-like phenotypes did not show a direct correlation with poor prognosis.

Aberrant keratin 7 and 20 expression in triple-negative carcinoma of the breast

Early studies characterizing the keratin (K) profile of various epithelial tissues indicated that breast carcinoma is K7 positive and K20 negative, but not all breast carcinomas show this profile. Triple-negative carcinoma (TNC) has been characterized by negativity for estrogen receptor (ER), progesterone receptor (PgR), and Her2/neu protein. TNC is more likely to metastasize to the viscera and present as a metastatic poorly different carcinoma. In our study, on the basis of immunohistochemical staining of ER, PgR, and Her2/neu, 75 of the 290 patients with invasive breast carcinoma were judged to have TNC. K20 expression was detected in 6 of 75 patients with TNC, and non-TNC was negative in all 215 cases (P = .0003). K7 expression was also detected in 72 of 75 TNC cases. However, non-TNC was negative in 26 of 215 cases, which was significant (P = .0457). An aberrant profile of K was observed in the TNC group, indicating that caution is needed in determining the site of primary tumors using immunohistochemical algorithms. It should be kept in mind that patients with TNC show highly variable K profiles in practical diagnosis.

Prevalence of molecular subtypes of invasive breast cancer: A retrospective study

BACKGROUND

Classification of breast cancers into different molecular subtypes using immunohistochemistry as a surrogate tool to DNA microarray technology has been identified. Aim of this study was to find the precise prevalence of molecular subtypes of invasive breast carcinoma using immunohistochemistry and to correlate it with histological and clinical prognostic factors.

METHODS

A descriptive study design wherein 56 breast carcinoma cases diagnosed between May 2012 and Apr 2014 were reviewed and molecular subtyped using relevant immunohistochemical markers. Age, histological type, tumor size, tumor grade, lymphovascular emboli (LVE), nodal status and basal marker expressions were analyzed for all cases. Correlations between molecular subtypes and clinico-pathological characteristics were evaluated statistically.

RESULTS

In our study group, average age of patients was 50.5 years and most of patients were diagnosed in stage II (54%). Luminal A subtype was most prevalent 34%, followed by Basal like/Triple negative subtype 25%. Luminal B and Her2/neu subtypes had same prevalence i.e. 18% each and Breast Tissue like/Unclassified subtype/Penta Negative subtype was 5%. All cases demonstrated positivity for the luminal cytokeratins 8/18. Histological grade and ER negative status showed strong correlations with basal markers.

CONCLUSION

On the basis of hormone receptor, Her2 neu, EGFR and CK 5/6 expressions, breast carcinoma cases were classified into five distinct molecular subtypes which show significant differences in regards to morphological features, prognostic markers and there by predicting possible clinical outcome.

Long non-coding RNA expression profiles predict metastasis in lymph node-negative breast cancer independently of traditional prognostic markers

INTRODUCTION

Patients with clinically and pathologically similar breast tumors often have very different outcomes and treatment responses. Current prognostic markers allocate the majority of breast cancer patients to the high-risk group, yielding high sensitivities in expense of specificities below 20%, leading to considerable overtreatment, especially in lymph node-negative patients. Seventy percent would be cured by surgery and radiotherapy alone in this group. Thus, precise and early indicators of metastasis are highly desirable to reduce overtreatment. Previous prognostic RNA-profiling studies have only focused on the protein-coding part of the genome, however the human genome contains thousands of long non-coding RNAs (lncRNAs) and this unexplored field possesses large potential for identification of novel prognostic markers.

METHODS

We evaluated lncRNA microarray data from 164 primary breast tumors from adjuvant naïve patients with a mean follow-up of 18 years. Eighty two patients who developed detectable distant metastasis were compared to 82 patients where no metastases were diagnosed. For validation, we determined the prognostic value of the lncRNA profiles by comparing the ability of the profiles to predict metastasis in two additional, previously-published, cohorts.

RESULTS

We showed that lncRNA profiles could distinguish metastatic patients from non-metastatic patients with sensitivities above 90% and specificities of 64-65%. Furthermore; classifications were independent of traditional prognostic markers and time to metastasis.

CONCLUSIONS

To our knowledge, this is the first study investigating the prognostic potential of lncRNA profiles. Our study suggest that lncRNA profiles provide additional prognostic information and may contribute to the identification of early breast cancer patients eligible for adjuvant therapy, as well as early breast cancer patients that could avoid unnecessary systemic adjuvant therapy. This study emphasizes the potential role of lncRNAs in breast cancer prognosis.

MUC1-mediated motility in breast cancer: a review highlighting the role of the MUC1/ICAM-1/Src signaling triad

Breast cancer is the most common cancer in women with the leading cause of death being metastasis, the spread of cancer to distant organs. For those patients with high-risk estrogen receptor positive (ER+) breast cancer, an increased expression of the glycoprotein MUC1 is associated with resistance to anti-hormonal therapy, metastasis and death. Tumor cells may use MUC1 to metastasize by exploiting the vascular adhesion pathways used by leukocytes during the inflammatory response. MUC1 is a type 1 transmembrane protein whose cytoplasmic tail acts as a scaffold for several signaling pathways including the non-receptor kinase Src, a signaling molecule involved in cell differentiation, proliferation, adhesion and motility. This review will highlight our current knowledge of how MUC1/ICAM-1 binding can lead to the recruitment and activation of Src and propose a novel role for lipid raft microdomains in this promigratory signaling. Improved understanding of the mechanism of metastases and the underlying signaling cascade is a prerequisite to the discovery of therapeutic targets to prevent metastasis and death in ER+ breast cancer patients.

microRNA expression profiling identifies a four microRNA signature as a novel diagnostic and prognostic biomarker in triple negative breast cancers

Triple Negative Breast Cancers (TNBC) is a heterogeneous disease at the molecular and clinical level with poor outcome. Molecular subclassification of TNBCs is essential for optimal use of current therapies and for development of new drugs. microRNAs (miRNA) are widely recognized as key players in cancer progression and drug resistance; investigation of their involvement in a TNBC cohort may reveal biomarkers for diagnosis and prognosis of TNBC. Here we stratified a large TNBC cohort into Core Basal (CB, EGFR and/or CK5, 6 positive) and five negative (5NP) if all markers are negative. We determined the complete miRNA expression profile and found a subset of miRNAs specifically deregulated in the two subclasses.

We identified a 4-miRNA signature given by miR-155, miR-493, miR-30e and miR-27a expression levels, that allowed subdivision of TNBCs not only into CB and 5NP subgroups (sensitivity 0.75 and specificity 0.56; AUC=0.74) but also into high risk and low risk groups. We tested the diagnostic and prognostic performances of both the 5 IHC marker panel and the 4-miRNA expression signatures, which clearly identify worse outcome patients in the treated and untreated subcohorts. Both signatures have diagnostic and prognostic value, predicting outcomes of patient treatment with the two most commonly used chemotherapy regimens in TNBC: anthracycline or anthracycline plus taxanes. Further investigation of the patients' overall survival treated with these regimens show that regardless of IHC group subdivision, taxanes addition did not benefit patients, possibly due to miRNA driven taxanes resistance. TNBC subclassification based on the 5 IHC markers and on the miR-155, miR-493, miR-30e, miR-27a expression levels are powerful diagnostic tools. Treatment choice and new drug development should consider this new subtyping and miRNA expression signature in planning low toxicity, maximum efficacy therapies.

Trp63 is regulated by STAT5 in mammary tissue and subject to differentiation in cancer

Transformation-related protein 63 (Trp63), the predominant member of the Trp53 family, contributes to epithelial differentiation and is expressed in breast neoplasia. Trp63 features two distinct promoters yielding specific mRNAs encoding two major TRP63 isoforms, a transactivating transcription factor and a dominant negative isoform. Specific TRP63 isoforms are linked to cell cycle arrest, apoptosis, survival, and epithelial mesenchymal transition (EMT). Although TRP63 overexpression in cultured cells is used to elucidate functions, little is known about Trp63 regulation in normal and cancerous mammary tissues. This study used ChIP-seq to interrogate transcription factor binding and histone modifications of the Trp63 locus in mammary tissue and RNA-seq and immunohistochemistry to gauge gene expression. H3K4me2 and H3K4me3 marks coincided only with the proximal promoter, supporting RNA-seq data showing the predominance of the dominant negative isoform. STAT5 bound specifically to the Trp63 proximal promoter and Trp63 mRNA levels were elevated upon deleting Stat5 from mammary tissue, suggesting its role as a negative regulator. The dominant negative TRP63 isoform was localized to nuclei of basal mammary epithelial cells throughout reproductive cycles and retained in a majority of the triple-negative cancers generated from loss of full-length Brca1. Increased expression of dominant negative isoforms was correlated with developmental windows of increased progesterone receptor binding to the proximal Trp63 promoter and decreased expression during lactation was correlated with STAT5 binding to the same region. TRP63 is present in the majority of triple-negative cancers resulting from loss of Brca1 but diminished in less differentiated cancer subtypes and in cancer cells undergoing EMT.

Differentiation and histogenesis of syringomatous tumour of the nipple and low-grade adenosquamous carcinoma: evidence for a common origin

AIMS

Syringomatous tumour of the nipple and low-grade adenosquamous carcinoma (LGAdSC) of the breast are regarded as distinct entities. To clarify the nature of these two lesions, we compared the expression of different lineage/differentiation markers in 12 syringomatous tumours of the nipple, nine LGAdSCs, and normal breast epithelium.

METHODS AND RESULTS

Using triple immunofluorescence labelling and quantitative RT-PCR for keratins, p63, and smooth muscle actin, we demonstrated that syringomatous tumour and LGAdSC contain p63+/K5/14+ tumour cells, K10+ squamous cells, and K8/18+ glandular cells, with intermediary cells being found in both lineages. Identical p63+/K5/14+ cells were also found in the normal breast duct epithelium.

CONCLUSIONS

Our data provide evidence that syringomatous tumour of the nipple and LGAdSC are identical or nearly identical lesions. They contain p63+/K5/14+ cells as the key cells from which the K10+ squamous lineage and the K8/18+ glandular lineage arise. On the basis of our findings in normal breast tissue and associated benign lesions, we suggest that p63+/K5/14+ cells of the normal breast duct epithelium or early related cells might play a key role in the neoplastic transformation of both syringomatous tumour and LGAdSC. We propose that the differentiation patterns found in both lesions reflect the early ontogenetic stages of the normal breast epithelium.

A Comparison of Tumor Biology in Primary Ductal Carcinoma In Situ Recurring as Invasive Carcinoma versus a New In Situ

Introduction. About half of all new ipsilateral events after a primary ductal carcinoma in situ (DCIS) are invasive carcinoma. We studied tumor markers in the primary DCIS in relation to type of event (invasive versus in situ). Methods. Two hundred and sixty-six women with a primary DCIS from two source populations, all with a known ipsilateral event, were included. All new events were regarded as recurrences. Patient and primary tumor characteristics (estrogen receptor (ER), progesterone receptor (PR), HER2, EGFR, and Ki67) were evaluated. Logistic regression was used to calculate odd ratios and 95% confidence intervals in univariate and multivariate analyses. Results. One hundred and thirty-six of the recurrences were invasive carcinoma and 130 were in situ. The recurrence was more often invasive if the primary DCIS was ER+ (OR 2.5, 95% CI 1.2–5.1). Primary DCIS being HER2+ (OR 0.5, 95% CI 0.3–0.9), EGFR+ (OR 0.4, 95% CI 0.2–0.9), and ER95−/HER2+ (OR 0.2, 95% CI 0.1–0.6) had a lower risk of a recurrence being invasive. Conclusions. In this study, comparing type of recurrence after a DCIS showed that the ER−/HER2+ tumors were related to a recurrence being a new DCIS. And surprisingly, tumors being ER+, HER2−, and EGFR− were related to a recurrence being invasive cancer.

The potential role of nanotechnology in therapeutic approaches for triple negative breast cancer

Triple Negative Breast Cancer, TNBC, a highly aggressive and metastatic type of breast cancer, is characterized by loss of expression of the estrogen receptor (ER), progesterone receptor (PR), and a lack of overexpression of the human epidermal growth factor receptor 2 (HER2). It is a heterogeneous group of tumors with diverse histology, molecular uniqueness and response to treatment. Unfortunately, TNBC patients do not benefit from current anti-HER2 or hormone positive targeted breast cancer treatments; consequently, these patients rely primarily on chemotherapy. However, the 5-year survival rate for woman with metastatic TNBC is less than 30%. As a result of ineffective treatments, TNBC tumors often progress to metastatic lesions in the brain and lung. Brain metastases of invasive breast cancer are associated with 1 and 2 year survival rate of 20% and <2% respectively. Because the only current systemic treatment for TNBC is chemotherapy, alternative targeted therapies are urgently needed to improve the prognosis for TNBC patients. This review is focused on opportunities for developing new approaches for filling the current void in an effective treatment for TNBC patients.

A machine learned classifier that uses gene expression data to accurately predict estrogen receptor status

Background

Selecting the appropriate treatment for breast cancer requires accurately determining the estrogen receptor (ER) status of the tumor. However, the standard for determining this status, immunohistochemical analysis of formalin-fixed paraffin embedded samples, suffers from numerous technical and reproducibility issues. Assessment of ER-status based on RNA expression can provide more objective, quantitative and reproducible test results.

Methods

To learn a parsimonious RNA-based classifier of hormone receptor status, we applied a machine learning tool to a training dataset of gene expression microarray data obtained from 176 frozen breast tumors, whose ER-status was determined by applying ASCO-CAP guidelines to standardized immunohistochemical testing of formalin fixed tumor.

Results

This produced a three-gene classifier that can predict the ER-status of a novel tumor, with a cross-validation accuracy of 93.17±2.44%. When applied to an independent validation set and to four other public databases, some on different platforms, this classifier obtained over 90% accuracy in each. In addition, we found that this prediction rule separated the patients' recurrence-free survival curves with a hazard ratio lower than the one based on the IHC analysis of ER-status.

Conclusions

Our efficient and parsimonious classifier lends itself to high throughput, highly accurate and low-cost RNA-based assessments of ER-status, suitable for routine high-throughput clinical use. This analytic method provides a proof-of-principle that may be applicable to developing effective RNA-based tests for other biomarkers and conditions.

Patterns of Recurrence and outcome according to breast cancer subtypes in lymph node-negative disease: results from international breast cancer study group trials VIII and IX

PURPOSE

To retrospectively evaluate the pattern of recurrence and outcome of node-negative breast cancer (BC) according to major subtypes.

PATIENTS AND METHODS

In all, 1,951 patients with node-negative, early-stage BC randomly assigned in International Breast Cancer Study Group Trials VIII and IX with centrally reviewed pathology data were included. BC subtypes were defined as triple negative (TN; n = 310), human epidermal growth factor receptor 2 (HER2) positive (n = 369), and hormone receptor positive with high (luminal B-like [LB-like]; n = 763) or low (luminal A-like [LA-like]; n = 509) proliferative activity by Ki-67 labeling index. BC-free interval (BCFI) events were invasive BC recurrence in local, contralateral breast, nodal, bone, or visceral sites. Time to first site-specific recurrence was evaluated by using cumulative incidence and competing risks regression analysis.

RESULTS

Median follow-up was 12.5 years. The 10-year BCFI was higher for patients with LA-like (86%) BC compared with LB-like (76%), HER2 (73%), and TN (71%; P < .001) BC. TN and HER2 cohorts had higher hazard of BCFI event in the first 4 years after diagnosis (pre-trastuzumab). LB-like cohorts had a continuously higher hazard of BCFI event over time compared with LA-like cohorts. Ten-year overall survival was higher for LA-like (89%) compared with LB-like (83%), HER2 (77%), and TN (75%; P < .001) BC. LB-like subtypes had higher rates of bone as first recurrence site than other subtypes (P = .005). Visceral recurrence as first site was lower for the LA-like subgroup, with similar incidence among the other subgroups when treated with chemotherapy (P = .003).

CONCLUSION

BC subtypes have different distant recurrence patterns over time. Defining different patterns of BC recurrence can improve BC care through surveillance guidelines and can guide the design of clinical studies.

Comparison of basal-like triple-negative breast cancer defined by morphology, immunohistochemistry and transcriptional profiles

Basal-like invasive breast cancer is an important clinical group because of its association with a triple-negative phenotype defined by the lack of expression of estrogen, progesterone and human epidermal growth factor receptors 2, relative lack of therapeutic options and poor prognosis. However, depending on the method used to define these lesions, morphological assessment, immunohistochemical markers or gene expression, a different set of tumors is captured. The aim of this study was to investigate the consequences of using different methodological approaches to define basal-like lesions among triple-negative breast carcinomas with regard to their clinicopathological features and patient outcome. The cohort consisted of 142 invasive breast cancers with a triple-negative receptor status. First, each was reviewed histologically and those with morphological basal-like features were characterized as 'Path-Basal'. Second, the 'Core Basal' immunohistochemical lesions, defined as cytokeratin 5/6 and/or epidermal growth factor receptor 1 positive, within the triple-negative breast cancers were identified, and third their classification based on gene expression profiling was retrieved and those in the molecular 'PAM50 basal-like' subtype recorded. A total of 116 basal-like breast cancers were identified among the 142 triple-negative breast cancers by at least one of these three classifications (80%), but only 13 samples were defined as basal-like with all three methods. None of these 13 tumors were associated with lymphovascular invasion. The 34 morphological 'Path-Basal' lesions were significantly associated with a lack of nodal metastases. Comparing the estimates of death in the three classifications, the highest risk of death was seen for the 'Core Basal' group. In this study, we highlight that the definition of basal-like breast cancer based on different methodologies varies significantly and does not identify the same lesions. This incomplete overlap of cases emphasizes the need for consistent or new approaches to improve precise identification.

A measure of the signal-to-noise ratio of microarray samples and studies using gene correlations

Background

The quality of gene expression data can vary dramatically from platform to platform, study to study, and sample to sample. As reliable statistical analysis rests on reliable data, determining such quality is of the utmost importance. Quality measures to spot problematic samples exist, but they are platform-specific, and cannot be used to compare studies.

Results

As a proxy for quality, we propose a signal-to-noise ratio for microarray data, the “Signal-to-Noise Applied to Gene Expression Experiments”, or SNAGEE. SNAGEE is based on the consistency of gene-gene correlations. We applied SNAGEE to a compendium of 80 large datasets on 37 platforms, for a total of 24,380 samples, and assessed the signal-to-noise ratio of studies and samples. This allowed us to discover serious issues with three studies. We show that signal-to-noise ratios of both studies and samples are linked to the statistical significance of the biological results.

Conclusions

We showed that SNAGEE is an effective way to measure data quality for most types of gene expression studies, and that it often outperforms existing techniques. Furthermore, SNAGEE is platform-independent and does not require raw data files. The SNAGEE R package is available in BioConductor.

Predictors of pathologic complete response after standard neoadjuvant chemotherapy in triple-negative breast carcinoma

The objective of this study was to identify predictors of pathologic complete response and tumor volume reduction in triple-negative breast carcinomas. Consecutive cases of 101 triple-negative carcinomas within the last 3 years treated with standard neoadjuvant chemotherapy were identified. However, 56 cases with sufficient material available (for tissue microarray construction) in the pretherapy core biopsy tissue blocks formed the basis of this study. The pretherapy tumor core biopsy slides were examined for various morphologic features including tumor grade. The tumors were immunohistochemically examined for basal phenotype markers (CK5, CK14, CK17, epidermal growth factor receptor), cell adhesion marker E-cadherin, and proliferation marker Ki-67. The overall rate of pathologic complete response was 34% (19 of 56). Neither any morphologic feature nor any basal marker reactivity predicted for pathologic complete response or >50% tumor volume reduction. Ki-67 proliferation index also failed as a predictive marker. Reduced E-cadherin expression (defined as H score ≤200) was initially seen in 47% of cases with pathologic complete response and in only 6% of cases that failed to achieve pathologic complete response (P=0.001); however, in additional 20 cases from a separate validation set, no such difference was identified. Basal marker reactivity in triple-negative breast carcinomas does not predict pathologic complete response after neoadjuvant chemotherapy. As vast majority of triple-negative tumors are highly proliferative, Ki-67 proliferation index appears to have negligible clinical value in predicting pathologic complete response. E-cadherin expression as a predictor of pathologic complete response in triple-negative tumors should be further assessed on larger number of cases.

Overexpression of epithelial growth factor receptor (EGFR) predicts better response to neo-adjuvant chemotherapy in patients with triple-negative breast cancer

Background

Triple negative breast cancer (TNBC) occurs in approximately 10% to 25% of all patients with breast cancer and is associated with poor prognosis. Neo-adjuvant chemotherapy has been reported to produce a higher pathologic complete response (pCR) rate in TNBC. If pCR is achieved, patients with TNBC had a similar survival with non-TNBC patients. The aim of our study was to investigate the protein expression of epithelial growth factor receptor (EGFR) and response to neo-adjuvant chemotherapy and clinical outcome in patients with TNBC compared with non-TNBC.

Methods

A total of 198 locally advanced breast cancer patients who received neo-adjuvant chemotherapy were studied. Immunohistochemistry (IHC) was carried out to detect the protein expression of EGFR in tumor samples. Clinical and pathological parameters, pCR rate and survival data were compared between 40 TNBCs and 158 non-TNBCs.

Results

In 198 cases who received neo-adjuvant chemotherapy, significant differences exist in surgical therapy (P=0.005) and pCR rate (P=0.012) between patients with TNBCs and non-TNBCs. Overexpression of EGFR was significantly associated with pCR rate in patients with TNBCs (P < 0.001). Survival analysis revealed that patients with TNBCs had worse DFS and OS than those with non-TNBCs (P = 0.001, P < 0.001 respectively). Furthermore, for patients with non-TNBCs, those who acheived pCR had better DFS and OS than those who acheived RD (both P < 0.001).

Conclusions

Our results suggested that patients with TNBCs had increased pCR rates compared with non-TNBC. Overexpression of EGFR predicted better response to neo-adjuvant chemotherapy in patients with TNBCs.

Prevalence of molecular subtypes and prognosis of invasive breast cancer in north-east of Morocco: retrospective study

Background

Breast carcinoma is known as a heterogeneous disease because gene expression analyses identify several subtypes and the molecular profiles are prognostic and predictive for patients. Our aim, in this study, is to estimate the prevalence of breast cancer subtypes and to determine the relationship between clinico-pathological characteristics, overall survival (OS) and disease free survival (DFS) for patients coming from north-east of Morocco.

Methods

We reviewed 366 cases of breast cancer diagnosed between January 2007 to June 2010 at the Department of pathology. Age, size tumor, metastatic profile, node involvement profile, OS and DFS were analyzed on 181 patients. These last parameters were estimated by Kaplan-Meier analysis and log-rank test to estimate outcome differences among subgroups.

Results

The average age was 45 years, our patients were diagnosed late (57% stage III, 17.5% stage IV) with a high average tumor size. Luminal A subtype was more prevalent (53.6%) associated with favorable clinic-pathological characteristics, followed by luminal B (16.4%), Her2-overexpressing (12.6%), basal-like (12.6%) and unclassified subtype (4.9%).

Survival analysis showed a significant difference between subtypes. The triple negative tumors were associated with poor prognosis (49% OS, 39% DFS), whereas the luminal A were associated with a better prognosis (88% OS, 59% DFS). The luminal B and the Her2-overexpressing subtypes were associated with an intermediate prognosis (77% and 75% OS, and 41% and 38% DFS respectively).

Conclusion

This study showed that molecular classification by immunohistochemistry was necessary for therapeutic decision and prognosis of breast carcinoma. The luminal A subtype was associated with favorable biological characteristics and a better prognosis than triple negative tumors that were associated with a poor prognosis and unfavorable clinic-pathological characteristics.

P-cadherin expression and basal-like subtype in breast cancers

Breast cancer is considered as one of the multifactorial diseases. The aim of the current study is to investigate the association between P-cadherin and molecular subtypes of breast cancer, especially the basal-like subtype. Two hundred and thirteen breast-invasive ductal carcinomas were involved in this study. The expressions of P-cadherin were detected via immunohistochemistry. The 213 cases were divided into luminal A, luminal B, HER2 overexpression subtype, and normal breast-like and basal-like subtypes according to the standard of molecular breast cancer subtypes. In addition, the expressions of CK5/6 and CK14 were detected to distinguish between the normal breast-like and the basal-like subtypes. P-cadherin expression was found in 91 cases of 213 breast-invasive ductal carcinomas, with a positive rate of 42.7%. P-cadherin correlated negatively with estrogen receptor (ER) (p=0.001) and progesterone receptor (p=0.001), whereas it positively correlated with histologic grade (p=0.003), NPI (p=0.005), p53 (p=0.038), and Ki67 (p=0.022). P-cadherin expression showed a strong correlation with recurrence and distant metastasis (p=0.009), and invasion of the vascular and soft tissues (p=0.004). Moreover, P-cadherin expression existed in the basal-like and non-basal-like subtypes. During prognosis, P-cadherin expression was associated with decreased disease-free survival in patients (p=0.009) and overall survival (OS) (p=0.005). In addition, multivariate analysis showed that tumor grade (p=0.021), ER (p=0.015), clinical stage (p=0.001), and P-cadherin (p=0.033) were significant predictors of OS. The current data suggest that P-cadherin may be used to distinguish the basal-like subtype and to predict the outcome in view of the relationship with DFS and OS. Furthermore, P-cadherin expression may be useful in making treatment decisions.

Dissecting the heterogeneity of triple-negative breast cancer

Triple-negative breast cancer (TNBC) accounts for 15% to 20% of breast cancers. It is a heterogeneous disease, not only on the molecular level, but also on the pathologic and clinical levels. TNBC is associated with a significantly higher probability of relapse and poorer overall survival in the first few years after diagnosis when compared with other breast cancer subtypes. This is observed despite its usual high sensitivity to chemotherapy. In the advanced setting, responses observed with chemotherapy lack durability. Early-stage clinical studies suggested impressive potential when a poly (ADP-ribose) polymerase (PARP) inhibitor is given for the treatment of advanced TNBC with BRCA gene dysfunction. The molecular complexity of TNBC has led to proposed subclassifications, which will be of great value for the development of targeted therapies. In this review, we discuss the biology of TNBC at the pathologic and the molecular levels. We also elaborate on the role of systemic therapies and the results of the first phase III clinical trial evaluating the addition of iniparib, a novel investigational anticancer agent that does not possess characteristics typical of the PARP inhibitor class, in combination with chemotherapy in advanced TNBC.

Laminin 332 expression in breast carcinoma

Laminin 332 (LN332) is a basally expressed extracellular matrix protein that enhances the migration and invasion of breast carcinoma cells. The goal of this study was to examine LN332 expression breast carcinoma. Triple negative breast carcinomas lack estrogen receptor (ER), progesterone receptor (PR) expression and HER2 positivity. Immunohistochemistry for ER, PR, HER2, and dual silver in situ hybridization for the HER2 gene were used to define the phenotype of 243 breast cancers in biopsies or arrays. Immunohistochemistry for LN332 revealed that 70% of triple negative carcinomas stained for LN332. Cytokeratins 5/6 (CK5/6), epidermal growth factor receptor and p63 alone stained fewer triple negative breast carcinomas each, but the combination of LN332 and CK5/6 or epidermal growth factor receptor identified 92% of triple negative breast carcinoma. Of the 163 non-triple negative cases, LN332 was expressed in only 15%. The identification of LN332 in triple negative breast carcinomas is consistent with gene profiling studies showing its expression among breast carcinomas with a basal phenotype. The observation that a proinvasive protein such as LN332 is expressed in breast cancer suggests another mechanism by which the triple negative phenotype could be aggressive.

Basal breast cancer: a complex and deadly molecular subtype

During the last decade, gene expression profiling of breast cancer has revealed the existence of five molecular subtypes and allowed the establishment of a new classification. The basal subtype, which represents 15-25% of cases, is characterized by an expression profile similar to that of myoepithelial normal mammary cells. Basal tumors are frequently assimilated to triple-negative (TN) breast cancers. They display epidemiological and clinico-pathological features distinct from other subtypes. Their pattern of relapse is characterized by frequent and early relapses and visceral locations. Despite a relative sensitivity to chemotherapy, the prognosis is poor. Recent characterization of their molecular features, such as the dysfunction of the BRCA1 pathway or the frequent expression of EGFR, provides opportunities for optimizing the systemic treatment. Several clinical trials dedicated to basal or TN tumors are testing cytotoxic agents and/or molecularly targeted therapies. This review summarizes the current state of knowledge of this aggressive and hard-to-treat subtype of breast cancer.

CD44 isoforms are heterogeneously expressed in breast cancer and correlate with tumor subtypes and cancer stem cell markers

Background

The CD44 cell adhesion molecule is aberrantly expressed in many breast tumors and has been implicated in the metastatic process as well as in the putative cancer stem cell (CSC) compartment. We aimed to investigate potential associations between alternatively spliced isoforms of CD44 and CSCs as well as to various breast cancer biomarkers and molecular subtypes.

Methods

We used q-RT-PCR and exon-exon spanning assays to analyze the expression of four alternatively spliced CD44 isoforms as well as the total expression of CD44 in 187 breast tumors and 13 cell lines. ALDH1 protein expression was determined by IHC on TMA.

Results

Breast cancer cell lines showed a heterogeneous expression pattern of the CD44 isoforms, which shifted considerably when cells were grown as mammospheres. Tumors characterized as positive for the CD44⁺/CD24^- phenotype by immunohistochemistry were associated to all isoforms except the CD44 standard (CD44S) isoform, which lacks all variant exons. Conversely, tumors with strong expression of the CSC marker ALDH1 had elevated expression of CD44S. A high expression of the CD44v2-v10 isoform, which retain all variant exons, was correlated to positive steroid receptor status, low proliferation and luminal A subtype. The CD44v3-v10 isoform showed similar correlations, while high expression of CD44v8-v10 was correlated to positive EGFR, negative/low HER2 status and basal-like subtype. High expression of CD44S was associated with strong HER2 staining and also a subgroup of basal-like tumors. Unsupervised hierarchical cluster analysis of CD44 isoform expression data divided tumors into four main clusters, which showed significant correlations to molecular subtypes and differences in 10-year overall survival.

Conclusions

We demonstrate that individual CD44 isoforms can be associated to different breast cancer subtypes and clinical markers such as HER2, ER and PgR, which suggests involvement of CD44 splice variants in specific oncogenic signaling pathways. Efforts to link CD44 to CSCs and tumor progression should consider the expression of various CD44 isoforms.

Triple-Negative Breast Cancer: Clinical and Histological Correlations

SUMMARY: Triple-negative breast cancer (TNBC) is characterized by the lack of estrogen and progesterone receptors and the lack of HER2 expression or amplification. Much interest has recently been focused on these triple-negative (TN) subtypes because they may be aggressive and are more likely to recur and metastasize than other subtypes of breast cancer. TNBC accounts for approximately 10-24% of all breast cancer cases, and typically it occurs in younger patients and in patients with BRCA1 mutation. There is a substantial heterogeneity of TNBCs both at the morphological and the molecular level, but there are also common features, such as low tumor grade and accelerated tumor proliferation. Morphologically, TNBC may present as invasive ductal, metaplastic, medullary, apocrine, or other types. Molecularly, they are most frequently associated with a basal phenotype, but there is a distinct subgroup of cancers that are not of basal type and belong to the claudin-low or molecular-apocrine type. The basal phenotype is frequently associated with the loss of BRCA1.

Basal phenotype breast cancer: implications for treatment and prognosis

Breast cancer is the most common malignancy in females. The origins and biology of breast carcinomas remain unclear. Cellular and molecular heterogeneity results in different distinct groups of tumors with different clinical behavior and prognosis. Gene expression profiling has delineated five molecular subtypes based on similarities in gene expression: luminal A, luminal B, HER2 overexpressing, normal-like and basal-like. Basal-like breast cancer (BLBC) lacks estrogen receptor, progesterone receptor and HER2 expression, and comprises myoepithelial cells. Specific features include high proliferative rate, rapid growth, early recurrence and decreased overall survival. BLBC is associated with ductal carcinoma in situ, BRCA1 mutation, brain and lung metastasis, and negative axillary lymph nodes. Currently, chemotherapy is the only therapeutic choice, but demonstrates poor outcomes. There is an overlap in definition between triple-negative breast cancer and BLBC due to the triple-negative profile of BLBC. Despite the molecular and clinical similarities, the two subtypes respond differently to neoadjuvant therapy. Although particular morphologic, genetic and clinical features of BLBC have been identified, a variety of definitions among studies accounts for the contradictory results reported. In this article the molecular morphological and histopathological profile, the clinical behavior and the therapeutic options of BLBC are presented, with emphasis on the discordant findings among studies.

The changing role of pathology in breast cancer diagnosis and treatment

Pathological examination has been the gold standard for diagnosis in cancer and its role has also included the elucidation of etiology, pathogenesis, clinicopathological correlation, and prognostication. The advent of newer technologies and the realization that breast cancer is heterogeneous has shifted the focus to prognostication, with increased attention being paid to the identification of morphological features and immunohistochemical markers of prognostic relevance. However, despite the massive efforts invested in the identification of immunohistochemical biomarkers in breast cancer the majority have not proven to be of value in multivariate analyses and only estrogen receptor, progesterone receptor, and Her2/neu expression have remained essential components of pathological examination. These 3 markers were initially employed for prognostication but their role in treatment also rendered them of predictive value. Newer molecular methods, especially high-throughput technologies, have shown that even morphologically similar subtypes of breast cancer can show molecular heterogeneity; moreover, infiltrating ductal carcinoma can be separated into at least 4 molecular subtypes designated luminal (ER+, PR+, and Her2/neu-), Her2 overexpressing (ER-, PR-, and Her2/neu+), basal-like (ER-, PR-, Her2/neu-, and CK5/6+, EGFR+), and normal breast-like (ER-, PR-, and Her2/neu-), each with different clinical outcomes. The importance of proliferative gene expression in these subtypes has been demonstrated and surrogate immunohistochemical markers include ER, PR, Her2/neu, and Ki67 for the more expensive molecular tests. Molecular technologies, importantly, have not only provided further insights into the heterogeneity of breast cancer but have also opened new avenues for treatment through the identification of signaling molecules important in the proliferation and survival of the neoplastic cells. The treatment of cancer thus shifts from the conventional approach of 'one size fits all' to one of personalized treatment tailored to the specific characteristics of the tumor. Pathologists continue to play their traditional role in diagnosis but, as purveyors of the excised tissue, pathologists now have the additional role of identifying biomarkers responsive to therapeutic manipulation, thus playing an inextricable role as diagnostic oncologists in the management of breast cancer.

Tumor-infiltrating lymphocytes are correlated with response to neoadjuvant chemotherapy in triple-negative breast cancer

The purpose of the present study was to identify histological surrogate predictive markers of pathological complete response (pCR) to neoadjuvant chemotherapy (NAC) in triple-negative breast cancer (TNBC). Among 474 patients who received NAC and subsequent surgical therapy for stage II-III invasive breast carcinoma between 1999 and 2007, 102 (22%) had TNBC, and 92 core needle biopsy (CNB) specimens obtained before NAC were available. As controls, CNB specimens from 42 tumors of the hormone receptor-negative and HER2-positive (HR-/HER2+) subtype and 46 tumors of the hormone receptor-positive and HER2-negative (HR+/HER2-) subtype were also included. Histopathological examination including tumor-infiltrating lymphocytes (TIL) and tumor cell apoptosis, and immunohistochemical studies for basal markers were performed, and the correlation of these data with pathological therapeutic effect was analyzed. The rates of pCR at the primary site were higher for TNBC (32%) and the HR-/HER2+ subtype (21%) than for the HR+/HER2- subtype (7%) (P = 0.006). Expression of basal markers and p53, histological grade 3, high TIL scores, and apoptosis were more frequent in TNBC and the HR-/HER2+ subtype than in the HR+/HER2- subtype (P = 0.002 for TIL and P < 0.001 for others). In TNBC, the pCR rates of tumors showing a high TIL score and of those showing a high apoptosis score were 37 and 47%, respectively, and significantly higher or tended to be higher than those of the tumors showing a low TIL score and of the tumors showing a low apoptosis score (16 and 27%, respectively, P = 0.05 and 0.10). In a total of 180 breast cancers, the pCR rates of the tumors showing a high TIL score (34%) and of those showing a high apoptosis score (35%) were significantly higher than those of the tumors showing a low TIL score (10%) and those of the tumors showing a low apoptosis score (19%) (P = 0.0001 and 0.04, respectively). Histological grade and basal marker expression were not correlated with pCR. Although the whole analysis was exploratory, the degree of TIL correlated with immune response appear to play a substantial role in the response to NAC in TNBC.

Metastatic triple-negative breast cancer

The triple-negative class (oestrogen receptor-negative, progesterone receptor-negative and human epidermal growth factor receptor 2 [HER2]-negative) comprises about 15% of breast cancer. It is associated with a poor prognosis compared with tumours that are positive for hormone receptors or HER2. Despite being sensitive to chemotherapy, many women with metastatic triple-negative breast cancer (TNBC) relapse quickly, and commonly develop visceral metastasis, including lung, liver and brain metastasis. TNBC has molecular features that overlap with breast cancer in BRCA1 germline mutation carriers and with those of the basal-like molecular class of tumours. Furthermore, tumours with the triple-negative phenotype have specific features and express markers that are potential therapeutic targets, for example an impaired DNA repair mechanism and increased expression of proliferation and basal-associated markers. The presence of these features has important implications for clinical practice and for the design of clinical trials looking at novel therapies. Targeted agents that are currently being investigated include poly (ADP-ribose) polymerase inhibitors, epidermal growth factor receptor inhibitors and anti-angiogenic compounds. Here we discuss the epidemiology, morphological and molecular spectrum of TNBC, the clinical significance of this important class of breast cancer and the current treatment options.

Basal-like and triple-negative breast cancers: a critical review with an emphasis on the implications for pathologists and oncologists

Breast cancer is a heterogeneous disease encompassing a variety of entities with distinct morphological features and clinical behaviors. Although morphology is often associated with the pattern of molecular aberrations in breast cancers, it is also clear that tumors of the same histological type show remarkably different clinical behavior. This is particularly true for 'basal-like cancer', which is an entity defined using gene expression analysis. The purpose of this article was to review the current state of knowledge of basal-like breast cancers, to discuss the relationship between basal-like and triple-negative breast cancers, and to clarify practical implications of these diagnoses for pathologists and oncologists.

Enhanced anticancer effect of the combination of cisplatin and TRAIL in triple-negative breast tumor cells

Women with triple-negative breast cancer (TNBC) have a worse prognosis compared with other breast cancer subtypes. Hormonal or Herceptin-based therapies were found to be ineffective because of the loss of target receptors, such as ER, PR, and HER-2 amplification. Conventional chemo- and/ or radiation therapy also seems to have limited efficacy in TNBC patients. We studied the effects of cisplatin plus TRAIL on 1 normal and 2 TNBC cells in vitro. The in vitro studies indicate that cisplatin plus TRAIL significantly enhanced cell death in TNBC cell lines CRL2335 and MDA-MB-468 by approximately 60%-70% compared with approximately 10%-15% in CRL8799 normal breast cell line. Treatment with cisplatin/TRAIL also inhibited the expression of EGFR, p63, survivin, Bcl-2, and Bcl-xL in TNBC cells. Specific inhibition of EGFR and/or p63 protein in TNBC cells by small interfering RNA (siRNA) does not increase TRAIL-induced apoptosis. However, inhibition of survivin by siRNA enhances TRAIL-induced apoptosis. These observations suggested the possibility that survivin played an important role in cisplatin plus TRAIL-induced apoptosis in TNBC cells. In vivo experiments, treatment of mice with cisplatin plus TRAIL resulted in a significant inhibition of CRL2335 xenograft tumors compared with untreated control tumors. Taken together the data suggest that cisplatin plus TRAIL treatment have the potential of providing a new strategy for improving the therapeutic outcome in TNBC patients.

Basal-like phenotype in a breast carcinoma case series from Sudan: prevalence and clinical/pathological correlations

Basal-like breast cancer, an aggressive subtype associated with high grade, poor prognosis, and younger age, is reported frequently in Africa. We analyzed the expression of the basal cytokeratins (CKs) 5/6 and 17 in a case series from Central Sudan and investigated correlations among basal CK status, ER, PgR, and Her-2/neu, and individual/clinicopathological data. Of 113 primary breast cancers 26 (23%), 38 (34%), and 46 (41%) were, respectively, positive for CK5/6, CK17, and combined basal CKs (CK5/6 and/or CK17). Combined basal CK+ status was associated with higher grade (P < .03) and inversely correlated with ER (P < .002), PgR (P = .004) and combined ER and/or PgR (P < .0002). Two clusters based on all tested markers were generated by hierarchical cluster analysis and k-mean clustering: I: designated "hormone receptors positive/luminal-like" and II: designated "hormone receptors negative", including both basal-like and Her-2/neu+ tumors. The most important factors for dataset variance were ER status, followed by PgR, CK17, and CK5/6 statuses. Overall basal CKs were expressed in a fraction of cases comparable to that reported for East and West African case series. Lack of associations with age and tumor size may represent a special feature of basal-like breast cancer in Sudan.

Triple-negative breast cancer: a short review

This review describes the pathology, prognosis, current treatment options, and future directions for the management of patients with triple-negative breast cancer. "Triple-negative" tumors lack expression of estrogen and progesterone receptors, and HER2. The subtype comprises some 15% of all breast cancers, with tumors of a typically larger size and higher grade. Clinically, triple-negative breast cancer has a relatively high rate of recurrence and distant metastasis, and poor overall survival. The standard of care is chemotherapy, although recent research suggests a sound rationale for the use of targeted agents with antitumor and/or antiangiogenic activity such as receptor tyrosine kinase inhibitors.

Clinicopathlogic and immunohistochemical characteristics of triple negative invasive lobular carcinoma

PURPOSE

Our study is performed to find out clinicopathlogic and immunohistochemical (IHC) characteristics of triple negative invasive lobular carcinoma (ILC), as has been demonstrated in their invasive ductal counterparts.

MATERIALS AND METHODS

Retrospective analysis of variable clinicopathlogic parameters and IHC stains for androgen receptor, estrogen receptor, progesterone receptor, p53, c-kit, galectin-3, cytokeratin 5 (CK5), CK5/6, vimentin, E-cadherin, epidermal growth factor receptor, and HER2 were performed in 117 cases of ILC.

RESULTS

Eight cases (6.8%) were triple negative carcinoma (TNC), which showed higher incidence of high histologic grade than non-TNC (p = 0.019). Galectin-3 was expressed with higher incidence in tumor cells of TNC (62.5%) than those of non-TNC (7.3%) (p = 0.000). In contrast, galectin-3 was expressed with higher incidence in stromal cells of non-TNC (53.2%) than those of TNC (12.5%) (p = 0.029). CK5 and CK5/6 were not expressed in all ILCs.

CONCLUSION

TNC in ILC showed distinct clinicopathologic and IHC characteristics such as higher histologic grade and increased expression of galectin-3, compared to non-TNC in ILC. TNC in ILC was less frequent and did not show CK5 and CK5/6 expression when compared to TNC in invasive ductal carcinoma.

Triple negative breast cancer: unmet medical needs

Triple negative breast cancer (TNBC) is an aggressive clinical phenotype characterized by lack of expression (or minimal expression) of estrogen receptor (ER) and progesterone receptor (PR) as well as an absence of human epidermal growth factor receptor-2 (HER2) overexpression. It shows substantial overlap with basal-type and BRCA1-related breast cancers, both of which also have aggressive clinical courses. However, this overlap is not complete, and the expression of ER, PR, and HER2 has been noted in basal-like tumors. TNBC also includes the normal-like subtype, and not all patients with TNBC harbor BRCA1 mutations. Because of its expression profile, TNBC is not amenable to treatment with hormone therapy or the anti-HER2 monoclonal antibody trastuzumab, and systemic treatment options are currently limited to cytotoxic chemotherapy. Overall survival, whether in early-stage or advanced disease, is poor compared with that in patients who have other phenotypes. A number of targeted approaches to TNBC are undergoing clinical evaluation, including the use of agents with poly(ADP-ribose) polymerase inhibitory properties such as iniparib (the United States Adopted Name for the investigational agent BSI-201), olaparib (AZD2281), and veliparib (ABT-888), antiangiogenic agents such as bevacizumab and sunitinib, and epidermal growth factor receptor blockers such as cetuximab and erlotinib. Encouraging results with some of these agents have been reported, thereby offering the promise for improved outcomes in patients with TNBC. The clinical characteristics of TNBC and clinical experience to date with novel targeted agents under development for this aggressive phenotype is reviewed.

Long-term survival of women with basal-like ductal carcinoma in situ of the breast: a population-based cohort study

BACKGROUND

Microarray gene-profiling of invasive breast cancer has identified different subtypes including luminal A, luminal B, HER2-overexpressing and basal-like groups. Basal-like invasive breast cancer is associated with a worse prognosis. However, the prognosis of basal-like ductal carcinoma in situ (DCIS) is still unknown. Our aim was to study the prognosis of basal-like DCIS in a large population-based cohort.

METHODS

All 458 women with a primary DCIS diagnosed between 1986 and 2004, in Uppland and Västmanland, Sweden were included. TMA blocks were constructed. To classify the DCIS tumors, we used immunohistochemical (IHC) markers (estrogen-, progesterone-, HER2, cytokeratin 5/6 and epidermal growth factor receptor) as a surrogate for the gene expression profiling. The association with prognosis was examined for basal-like DCIS and other subtypes using Kaplan-Meier survival analyses and Cox proportional hazards regression models.

RESULTS

IHC data were complete for 392 women. Thirty-two were basal-like (8.2%), 351 were luminal or HER2-positive (89.5%) and 9 unclassified (2.3%). Seventy-six women had a local recurrence of which 34 were invasive. Another 3 women had general metastases as first event. Basal-like DCIS showed a higher risk of local recurrence and invasive recurrence 1.8 (Confidence interval (CI) 95%, 0.8-4.2) and 1.9 (0.7-5.1), respectively. However, the difference was not statistically significant. Also, no statistically significant increased risk was seen for triple-negative or high grade DCIS.

CONCLUSIONS

Basal-like DCIS showed about a doubled, however not statistically significant risk for local recurrence and developing invasive cancer compared with the other molecular subtypes. Molecular subtyping was a better prognostic parameter than histopathological grade.

Vascular Invasion in Triple-Negative Carcinoma of the Breast Identified by Endothelial Lymphatic and Blood Vessel Markers

The aim of this study was to determine lymph vessel invasion (LVI) and blood vessel invasion (BVI) using established biological markers and clinicopathological findings for triple-negative breast carcinoma. We reviewed all 202 cases of primary breast carcinoma that were surgically resected at Saitama Medical Center, Saitama Medical School, between 2006 and 2009. Tumor tissue was immunostained for estrogen receptor, progesterone receptor, Her2/neu, D2-40, and CD34. Among these, 26 cases of triple-negative carcinoma were reported retrospectively. The results were compared with those of 176 cases of non-triple-negative carcinomas that were included as controls. The frequency of LVI examined by hematoxylin and eosin and D2-40 (triple negative, 7 of 26; non—triple negative, 61 of 176) was not significantly different, and neither was BVI examined by HE, Elastica van Gieson, CD34 (triple negative, 2 of 26; non—triple negative, 16 of 176), and lymph node metastasis (triple negative 9 of 26, non—triple negative, 65 of 176). However, a specific pattern of distant metastasis with a high frequency of visceral metastases was detected in triple-negative carcinoma cases (triple negative, 6 of 26; non—triple negative, 8 of 176). Our findings show that triple-negative carcinoma of the breast may have a distinct biological behavior.

Triple-negative breast cancer: disease entity or title of convenience?

This Review outlines the understanding and management of triple-negative breast cancer (TNBC). TNBC shares morphological and genetic abnormalities with basal-like breast cancer (BLBC), a subgroup of breast cancer defined by gene-expression profiling. However, TNBC and BLBC tumors are heterogeneous and overlap is incomplete. Breast cancers found in BRCA1 mutation carriers are also frequently triple negative and basal like. TNBC and BLBC occur most frequently in young women, especially African Americans, and tend to exhibit aggressive, metastatic behavior. These tumors respond to conventional chemotherapy but relapse more frequently than hormone receptor-positive, luminal subtypes and have a worse prognosis. New systemic therapies are urgently needed as most patients with TNBC and/or BLBC relapse with distant metastases, and hormonal therapies and HER2-targeted agents are ineffective in this group of tumors. Poly (ADP-ribose) polymerase inhibitors, angiogenesis inhibitors, EGFR-targeted agents, and src kinase and mTOR inhibitors are among the therapeutic agents being actively investigated in clinical trials in patients with TNBC and/or BRCA1-associated tumors. Increased understanding of the genetic abnormalities involved in the pathogenesis of TNBC, BLBC and BRCA1-associated tumors is opening up new therapeutic possibilities for these hard-to-treat breast cancers.

Molecular therapy of breast cancer: progress and future directions

Breast cancer is a major cause of death in Western women, with a 10% lifetime risk of the disease. Most breast cancers are estrogen-dependent. Molecular therapies for breast cancer have developed rapidly in the past few decades and future treatment strategies are being investigated. The selective estrogen receptor (ER) modulator tamoxifen, which until now has served as a standard therapy, functions not only as an estrogen antagonist but also as an estrogen agonist in terms of bone maintenance. Aromatase inhibitors have performed well in international trials and have become a new standard therapy for estrogen-dependent breast cancer. The systematic study of estrogen activation pathways suggests that the enzymes steroid sulfatase and 17beta-hydroxysteroid dehydrogenase type 1, which both have pivotal roles in estrogen biosynthesis, are promising targets; the results of a phase I trial of steroid sulfatase inhibitors are encouraging. The activity of the human epidermal growth factor receptor (HER) pathway correlates negatively with that of the ER. HER2 is overexpressed in 22% of all breast cancers. In the decade since HER2 began being targeted, the monoclonal antibody trastuzumab has been used as well as pertuzumab and HER2 vaccines. Among the estrogen-independent breast cancers, the basal-like subtype has low survival, and therapeutic improvement is a priority. Crosstalk between ER and HER2 signaling pathways means that combinatory therapies may hold the key to enhancement of treatment responses. Other molecular therapies involving functional genomics and RNA interference studies also hold promise.

Personalized medicine: marking a new epoch in cancer patient management

Personalized medicine (PM) is defined as "a form of medicine that uses information about a person's genes, proteins, and environment to prevent, diagnose, and treat disease." The promise of PM has been on us for years. The suite of clinical applications of PM in cancer is broad, encompassing screening, diagnosis, prognosis, prediction of treatment efficacy, patient follow-up after surgery for early detection of recurrence, and the stratification of patients into cancer subgroup categories, allowing for individualized therapy. PM aims to eliminate the "one size fits all" model of medicine, which has centered on reaction to disease based on average responses to care. By dividing patients into unique cancer subgroups, treatment and follow-up can be tailored for each individual according to disease aggressiveness and the ability to respond to a certain treatment. PM is also shifting the emphasis of patient management from primary patient care to prevention and early intervention for high-risk individuals. In addition to classic single molecular markers, high-throughput approaches can be used for PM including whole genome sequencing, single-nucleotide polymorphism analysis, microarray analysis, and mass spectrometry. A common trend among these tools is their ability to analyze many targets simultaneously, thus increasing the sensitivity, specificity, and accuracy of biomarker discovery. Certain challenges need to be addressed in our transition to PM including assessment of cost, test standardization, and ethical issues. It is clear that PM will gradually continue to be incorporated into cancer patient management and will have a significant impact on our health care in the future.