RESUMEN
Brain metastasis is a significant challenge for some breast cancer patients, marked by its aggressive nature, limited treatment options, and poor clinical outcomes. Immunotherapies have emerged as a promising avenue for brain metastasis treatment. B7-H3 (CD276) is an immune checkpoint molecule involved in T cell suppression, which is associated with poor survival in cancer patients. Given the increasing number of clinical trials using B7-H3 targeting CAR T cell therapies, we examined B7-H3 expression across breast cancer subtypes and in breast cancer brain metastases to assess its potential as an interventional target. B7-H3 expression was investigated using immunohistochemistry on tissue microarrays of three clinical cohorts: (i) unselected primary breast cancers (n = 347); (ii) brain metastatic breast cancers (n = 61) and breast cancer brain metastases (n = 80, including a subset of 53 patient-matched breast and brain metastasis cases); and (iii) mixed brain metastases from a range of primary tumours (n = 137). In primary breast cancers, B7-H3 expression significantly correlated with higher tumour grades and aggressive breast cancer subtypes, as well as poorer 5-year survival outcomes. Subcellular localisation of B7-H3 impacted breast cancer-specific survival, with cytoplasmic staining also correlating with a poorer outcome. Its expression was frequently detected in brain metastases from breast cancers, with up to 90% expressing B7-H3. However, not all brain metastases showed high levels of expression, with those from colorectal and renal tumours showing a low frequency of B7-H3 expression (0/14 and 2/16, respectively). The prevalence of B7-H3 expression in breast cancers and breast cancer brain metastases indicates potential opportunities for B7-H3 targeted therapies in breast cancer management.
Asunto(s)
Neoplasias Encefálicas , Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/genética , Mama , Encéfalo , Agresión , Factores de Transcripción , Antígenos B7/genéticaRESUMEN
Breast cancer brain metastases (BM) are associated with a dismal prognosis and very limited treatment options. Standard chemotherapy is challenging in BM patients because the high dosage required for an effective outcome causes unacceptable systemic toxicities, a consequence of poor brain penetration, and a short physiological half-life. Nanomedicines have the potential to circumvent off-target toxicities and factors limiting the efficacy of conventional chemotherapy. The HER3 receptor is commonly expressed in breast cancer BM. Here, we investigate the use of hyperbranched polymers (HBP) functionalized with a HER3 bispecific-antibody fragment for cancer cell-specific targeting and pH-responsive release of doxorubicin (DOX) to selectively deliver and treat BM. We demonstrated that DOX-release from the HBP carrier was controlled, gradual, and greater in endosomal acidic conditions (pH 5.5) relative to physiologic pH (pH 7.4). We showed that the HER3-targeted HBP with DOX payload was HER3-specific and induced cytotoxicity in BT474 breast cancer cells (IC50: 17.6 µg/mL). Therapeutic testing in a BM mouse model showed that HER3-targeted HBP with DOX payload impacted tumor proliferation, reduced tumor size, and prolonged overall survival. HER3-targeted HBP level detected in ex vivo brain samples was 14-fold more than untargeted-HBP. The HBP treatments were well tolerated, with less cardiac and oocyte toxicity compared to free DOX. Taken together, our HER3-targeted HBP nanomedicine has the potential to deliver chemotherapy to BM while reducing chemotherapy-associated toxicities.
Asunto(s)
Neoplasias Encefálicas , Neoplasias de la Mama , Nanopartículas , Animales , Ratones , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Línea Celular Tumoral , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Polímeros/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Concentración de Iones de Hidrógeno , Sistemas de Liberación de Medicamentos , Liberación de FármacosRESUMEN
Breast cancer risk is influenced by rare coding variants in susceptibility genes, such as BRCA1, and many common, mostly non-coding variants. However, much of the genetic contribution to breast cancer risk remains unknown. Here we report the results of a genome-wide association study of breast cancer in 122,977 cases and 105,974 controls of European ancestry and 14,068 cases and 13,104 controls of East Asian ancestry. We identified 65 new loci that are associated with overall breast cancer risk at P < 5 × 10-8. The majority of credible risk single-nucleotide polymorphisms in these loci fall in distal regulatory elements, and by integrating in silico data to predict target genes in breast cells at each locus, we demonstrate a strong overlap between candidate target genes and somatic driver genes in breast tumours. We also find that heritability of breast cancer due to all single-nucleotide polymorphisms in regulatory features was 2-5-fold enriched relative to the genome-wide average, with strong enrichment for particular transcription factor binding sites. These results provide further insight into genetic susceptibility to breast cancer and will improve the use of genetic risk scores for individualized screening and prevention.
Asunto(s)
Neoplasias de la Mama/genética , Sitios Genéticos , Predisposición Genética a la Enfermedad/genética , Estudio de Asociación del Genoma Completo , Asia/etnología , Pueblo Asiatico/genética , Sitios de Unión/genética , Neoplasias de la Mama/diagnóstico , Simulación por Computador , Europa (Continente)/etnología , Femenino , Humanos , Herencia Multifactorial/genética , Polimorfismo de Nucleótido Simple/genética , Secuencias Reguladoras de Ácidos Nucleicos , Medición de Riesgo , Factores de Transcripción/metabolismo , Población Blanca/genéticaRESUMEN
Invasive lobular carcinoma (ILC) is the most common of the breast cancer special types, accounting for up to 15% of all breast cancer cases. ILCs are noted for their lack of E-cadherin function, which underpins their characteristic discohesive growth pattern, with cells arranged in single file and dispersed throughout the stroma. Typically, tumours are luminal in molecular subtype, being oestrogen and progesterone receptor positive, and HER2 negative. Since last reviewing the lobular literature (McCart Reed et al., Breast Cancer Res 17:12, 2015), there has been a considerable increase in research output focused on this tumour type, including studies into the pathology and management of disease, a high-resolution definition of the genomic landscape of tumours as well as the evolution of several potential therapeutic avenues. There abounds a huge amount of new data, which we will review herein.
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Neoplasias de la Mama/diagnóstico , Carcinoma Lobular/diagnóstico , Biomarcadores de Tumor , Neoplasias de la Mama/etiología , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/terapia , Carcinoma Lobular/etiología , Carcinoma Lobular/mortalidad , Carcinoma Lobular/terapia , Diagnóstico Diferencial , Progresión de la Enfermedad , Susceptibilidad a Enfermedades , Resistencia a Antineoplásicos/genética , Femenino , Expresión Génica , Genómica/métodos , Humanos , Mutación , Clasificación del Tumor , Estadificación de Neoplasias , Fenotipo , Pronóstico , Microambiente TumoralRESUMEN
BACKGROUND: Breast cancers acquire aggressive capabilities via epithelial to mesenchymal transition (EMT), in which various integrins/integrin-linked kinase signalling are upregulated. METHODS: We investigated this in two patient-derived xenografts (PDXs) developed from breast-to-bone metastases, and its functional significance in a breast cancer cell line system. ED03 and EDW01 PDXs were grown subcutaneously in immunocompromised SCID mice through 11 passages and 7 passages, respectively. Tumour tissue was assessed using immunohistochemistry (IHC) for oestrogen receptor (ER)-alpha, E-cadherin, vimentin, Twist1, beta-catenin, P120-RasGAP, CD44, CD24 and Ki67, and RT-qPCR of EMT-related factors (CDH1, VIM, CD44, CD24), integrins beta 1 (ITGB1), alpha 2 (ITGA2) and ILK. Integrin and ILK expression in epidermal growth factor (EGF)-induced EMT of the PMC42-ET breast cancer cell line was assessed by RT-qPCR and Western blotting, as were the effects of their transient knockdown via small interfering RNA +/- EGF. Cell migration, changes in cell morphology and adhesion of siRNA-transfected PMC42-ET cells to various extracellular matrix (ECM) substrates was assessed. RESULTS: The ED03 (ER+/PR-/HER2-/lobular) and EDW01 (ER+/PR-/HER2-/ductal) PDXs were both classified as molecular subtype luminal A. ED03 xenografts exhibited mutated E-cadherin with minimal expression, but remained vimentin-negative across all passages. In EDW01, the hypoxic indicator gene CAIX and Twist1 were co-ordinately upregulated at passages 4-5, corresponding with a decrease in E-cadherin. At passages 6-7, VIM was upregulated along with ITGB1 and ITGA2, consistent with an increasing EMT. The ED03 PDX displayed minimal change over passages in mice, for all genes examined. ILK, ITGB1 and ITGA2 mRNAs were also increased in the EGF-induced EMT of PMC42-ET cells (in which CDH1 was downregulated) although siRNA against these targets revealed that this induction was not necessary for the observed EMT. However, their knockdown significantly reduced EMT-associated adhesion and Transwell migration. CONCLUSION: Our data suggest that despite an increase in ITGA2 and ITGB1 gene expression in the EMT exhibited by EDW01 PDX over multiple generations, this pathway may not necessarily drive the EMT process.
Asunto(s)
Neoplasias Óseas/genética , Neoplasias de la Mama/genética , Carcinoma Ductal de Mama/genética , Transición Epitelial-Mesenquimal/genética , Integrina alfa2/genética , Integrina beta1/genética , Adulto , Animales , Neoplasias Óseas/secundario , Mama/patología , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/secundario , Línea Celular Tumoral , Movimiento Celular/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Ratones , Proteínas Serina-Treonina Quinasas/genética , Regulación hacia Arriba , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: Metaplastic breast carcinoma encompasses a heterogeneous group of tumours with differentiation into squamous and/or spindle, chondroid, osseous or rhabdoid mesenchymal-looking elements. Emerging immunotherapies targeting Programmed Death Ligand 1 (PD-L1) and immune-suppressing T cells (Tregs) may benefit metaplastic breast cancer patients, which are typically chemo-resistant and do not express hormone therapy targets. METHODS: We evaluated the immunohistochemical expression of PD-L1 and FOXP3, and the extent of tumour infiltrating lymphocytes (TILs) in a large cohort of metaplastic breast cancers, with survival data. RESULTS: Metaplastic breast cancers were significantly enriched for PD-L1 positive tumour cells, compared to triple-negative ductal breast cancers (P < 0.0001), while there was no significant difference in PD-L1 positive TILs. Metaplastic breast cancers were also significantly enriched for TILs expressing FOXP3, with FOXP3 positive intra-tumoural TILs (iTILs) associated with an adverse prognostic outcome (P = 0.0226). Multivariate analysis identified FOXP3 iTILs expression status as an important independent prognostic factor for patient survival. CONCLUSIONS: Our findings indicate the clinical significance and prognostic value of FOXP3, PD-1/PD-L1 checkpoint and TILs in metaplastic breast cancer and confirm that a subset of metaplastics may benefit from immune-based therapies.
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Antígeno B7-H1/biosíntesis , Biomarcadores de Tumor/inmunología , Neoplasias de la Mama/patología , Factores de Transcripción Forkhead/biosíntesis , Adulto , Anciano , Neoplasias de la Mama/inmunología , Femenino , Humanos , Inhibidores de Puntos de Control Inmunológico , Linfocitos Infiltrantes de Tumor/inmunología , Metaplasia , Persona de Mediana EdadRESUMEN
During the last decade, the genomics revolution has driven critical advances in molecular oncology and pathology, and a deeper appreciation of heterogeneity that is beginning to reshape our thinking around diagnostic classification. Recent developments have seen existing classification systems modified and improved where possible, gene-based diagnostics implemented and tumour-immune interactions modulated. We present a detailed discussion of this progress, including advances in the understanding of breast tumour classification, e.g. mixed ductal-lobular tumours and the spectrum of triple-negative breast cancer. The latest information on clinical trials and the implementation of gene-based diagnostics, including MammaPrint and Oncotype Dx and others, is synthesised, and emerging targeted therapies, as well as the burgeoning immuno-oncology field, and their relevance in breast cancer, are discussed. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/terapia , Femenino , Genes BRCA1/fisiología , Genes BRCA2/fisiología , Genes Relacionados con las Neoplasias/genética , Genómica , Humanos , Linfocitos Infiltrantes de Tumor/fisiología , Terapia Molecular Dirigida/métodos , PronósticoRESUMEN
Mixed ductal-lobular carcinomas (MDLs) show both ductal and lobular morphology, and constitute an archetypal example of intratumoural morphological heterogeneity. The mechanisms underlying the coexistence of these different morphological entities are poorly understood, although theories include that these components either represent 'collision' of independent tumours or evolve from a common ancestor. We performed comprehensive clinicopathological analysis of a cohort of 82 MDLs, and found that: (1) MDLs more frequently coexist with ductal carcinoma in situ (DCIS) than with lobular carcinoma in situ (LCIS); (2) the E-cadherin-catenin complex was normal in the ductal component in 77.6% of tumours; and (3) in the lobular component, E-cadherin was almost always aberrantly located in the cytoplasm, in contrast to invasive lobular carcinoma (ILC), where E-cadherin is typically absent. Comparative genomic hybridization and multiregion whole exome sequencing of four representative cases revealed that all morphologically distinct components within an individual case were clonally related. The mutations identified varied between cases; those associated with a common clonal ancestry included BRCA2, TBX3, and TP53, whereas those associated with clonal divergence included CDH1 and ESR1. Together, these data support a model in which separate morphological components of MDLs arise from a common ancestor, and lobular morphology can arise via a ductal pathway of tumour progression. In MDLs that present with LCIS and DCIS, the clonal divergence probably occurs early, and is frequently associated with complete loss of E-cadherin expression, as in ILC, whereas, in the majority of MDLs, which present with DCIS but not LCIS, direct clonal divergence from the ductal to the lobular phenotype occurs late in tumour evolution, and is associated with aberrant expression of E-cadherin. The mechanisms driving the phenotypic change may involve E-cadherin-catenin complex deregulation, but are yet to be fully elucidated, as there is significant intertumoural heterogeneity, and each case may have a unique molecular mechanism. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Asunto(s)
Carcinoma de Mama in situ/patología , Neoplasias de la Mama/patología , Carcinoma Intraductal no Infiltrante/patología , Neoplasias Complejas y Mixtas/patología , Adulto , Anciano , Anciano de 80 o más Años , Antígenos CD/análisis , Antígenos CD/genética , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Carcinoma de Mama in situ/química , Carcinoma de Mama in situ/genética , Neoplasias de la Mama/química , Neoplasias de la Mama/genética , Cadherinas/análisis , Cadherinas/genética , Carcinoma Intraductal no Infiltrante/química , Carcinoma Intraductal no Infiltrante/genética , Hibridación Genómica Comparativa , Análisis Mutacional de ADN , Progresión de la Enfermedad , Femenino , Predisposición Genética a la Enfermedad , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Mutación , Neoplasias Complejas y Mixtas/química , Neoplasias Complejas y Mixtas/genética , Fenotipo , Secuenciación del ExomaRESUMEN
BACKGROUND: Next-generation sequencing (NGS) in lung cancer specimens from endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) is usually performed on formalin-fixed paraffin-embedded cell block material. OBJECTIVES: Since DNA can be damaged by this process, we investigated the potential of using DNA extracted from Diff-Quik cytology smears made for rapid on-site evaluation during EBUS-TBNA. METHODS: In a prospective study, 67 patients undergoing diagnostic EBUS-TBNA were ana-lysed. We compared cell blocks and smears for DNA yields and sequencing (TruSeq Amplicon Cancer Panel) outcomes. Smears were also evaluated for tumour cell fraction and overall cellularity (cell count). RESULTS: Primary lung cancer was diagnosed in 64 patients and metastatic malignancy in 3 patients. The DNA yield from smears was significantly higher than that obtained from matched cell blocks (mean 1,740 vs. 434 ng; p = 0.001). For 33 cases with matched smears and cell blocks the mutation profiles were similar. Smears with abundant malignant cells (using a cut-off of > 25% tumour cell fraction and > 1,000 cells) accurately predicted high (> 50 ng) DNA yield and therefore success in triaging samples to sequencing. In terms of tissue workflow, using only smears as source DNA for sequencing was an improvement in the use of only cell blocks (54/67 [80.6%] vs. 41/67 [61.2%]); however, the use of cell blocks when smears were not available or did not yield sufficient DNA further improved the success rate to 62/67 (92.5%) cases. CONCLUSION: We recommend smears in laboratory workflows as the primary source of DNA for NGS following an EBUS procedure.
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Colorantes Azulados , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , Secuenciación de Nucleótidos de Alto Rendimiento , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Azul de Metileno , Xantenos , Anciano , Anciano de 80 o más Años , Endosonografía , Femenino , Humanos , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
Breast cancer encompasses a heterogeneous collection of neoplasms with diverse morphologies, molecular phenotypes, responses to therapy, probabilities of relapse and overall survival. Traditional histopathological classification aims to categorise tumours into subgroups to inform clinical management decisions, but the diversity within these subgroups remains considerable. Application of massively parallel sequencing technologies in breast cancer research has revealed the true depth of variability in terms of the genetic, phenotypic, cellular and microenvironmental constitution of individual tumours, with the realisation that each tumour is exquisitely unique. This poses great challenges in predicting the development of drug resistance, and treating metastatic disease. Central to achieving fully personalised clinical management is translating new insights on breast cancer heterogeneity into the clinical setting, to evolve the taxonomy of breast cancer and improve risk stratification.
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Neoplasias de la Mama/patología , Neoplasias Primarias Secundarias/patología , Resistencia a Antineoplásicos , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Recurrencia Local de NeoplasiaRESUMEN
Predicting response to endocrine therapy and survival in oestrogen receptor positive breast cancer is a significant clinical challenge and novel prognostic biomarkers are needed. Long-range regulators of gene expression are emerging as promising biomarkers and therapeutic targets for human diseases, so we have explored the potential of distal enhancer elements of non-coding RNAs in the prognostication of breast cancer survival. HOTAIR is a long non-coding RNA that is overexpressed, promotes metastasis and is predictive of decreased survival. Here, we describe a long-range transcriptional enhancer of the HOTAIR gene that binds several hormone receptors and associated transcription factors, interacts with the HOTAIR promoter and augments transcription. This enhancer is dependent on Forkhead-Box transcription factors and functionally interacts with a novel alternate HOTAIR promoter. HOTAIR expression is negatively regulated by oestrogen, positively regulated by FOXA1 and FOXM1, and is inversely correlated with oestrogen receptor and directly correlated with FOXM1 in breast tumours. The combination of HOTAIR and FOXM1 enables greater discrimination of endocrine therapy responders and non-responders in patients with oestrogen receptor positive breast cancer. Consistent with this, HOTAIR expression is increased in cell-line models of endocrine resistance. Analysis of breast cancer gene expression data indicates that HOTAIR is co-expressed with FOXA1 and FOXM1 in HER2-enriched tumours, and these factors enhance the prognostic power of HOTAIR in aggressive HER2+ breast tumours. Our study elucidates the transcriptional regulation of HOTAIR, identifies HOTAIR and its regulators as novel biomarkers of patient response to endocrine therapy and corroborates the importance of transcriptional enhancers in cancer.
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Biomarcadores de Tumor/biosíntesis , Neoplasias de la Mama/metabolismo , Regulación Neoplásica de la Expresión Génica , ARN Largo no Codificante/biosíntesis , ARN Neoplásico/biosíntesis , Transcripción Genética , Biomarcadores de Tumor/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Proteína Forkhead Box M1/biosíntesis , Proteína Forkhead Box M1/genética , Factor Nuclear 3-alfa del Hepatocito/biosíntesis , Factor Nuclear 3-alfa del Hepatocito/genética , Humanos , Células MCF-7 , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , ARN Largo no Codificante/genética , ARN Neoplásico/genéticaRESUMEN
PURPOSE: Cell lines are extremely useful tools in breast cancer research. Their key benefits include a high degree of control over experimental variables and reproducibility. However, the advantages must be balanced against the limitations of modelling such a complex disease in vitro. Informed selection of cell line(s) for a given experiment now requires essential knowledge about molecular and phenotypic context in the culture dish. METHODS: We performed multidimensional profiling of 36 widely used breast cancer cell lines that were cultured under standardised conditions. Flow cytometry and digital immunohistochemistry were used to compare the expression of 14 classical breast cancer biomarkers related to intrinsic molecular profiles and differentiation states: EpCAM, CD24, CD49f, CD44, ER, AR, HER2, EGFR, E-cadherin, p53, vimentin, and cytokeratins 5, 8/18 and 19. RESULTS: This cell-by-cell analysis revealed striking heterogeneity within cultures of individual lines that would be otherwise obscured by analysing cell homogenates, particularly amongst the triple-negative lines. High levels of p53 protein, but not RNA, were associated with somatic mutations (p = 0.008). We also identified new subgroups using the nanoString PanCancer Pathways panel (730 transcripts representing 13 canonical cancer pathways). Unsupervised clustering identified five groups: luminal/HER2, immortalised ('normal'), claudin-low and two basal clusters, distinguished mostly by baseline expression of TGF-beta and PI3-kinase pathway genes. CONCLUSION: These features are compared with other published genotype and phenotype information in a user-friendly reference table to help guide selection of the most appropriate models for in vitro and in vivo studies, and as a framework for classifying new patient-derived cancer cell lines and xenografts.
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Neoplasias de la Mama/genética , Perfilación de la Expresión Génica , Heterogeneidad Genética , Proteínas de Neoplasias/genética , Línea Celular Tumoral , Femenino , Citometría de Flujo , Regulación Neoplásica de la Expresión Génica/genética , Genotipo , Humanos , FenotipoRESUMEN
The use of molecular signatures to add value to standard clinical and pathological parameters has impacted clinical practice in many cancer types, but perhaps most notably in the breast cancer field. This is, in part, due to the considerable complexity of the disease at the clinical, morphological and molecular levels. The adoption of molecular profiling of DNA, RNA and protein continues to reveal important differences in the intrinsic biology between molecular subtypes and has begun to impact the way patients are managed. Several bioinformatic tools have been developed using DNA or RNA-based signatures to stratify the disease into biologically and/or clinically meaningful subgroups. Here, we review the approaches that have been used to develop gene expression signatures into currently available diagnostic assays (e.g., OncotypeDX® and Mammaprint®), plus we describe the latest work on genome sequencing, the methodologies used in the discovery process of mutational signatures, and the potential of these signatures to impact the clinic.
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Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , Transcriptoma/genética , Neoplasias de la Mama/patología , Biología Computacional , Femenino , Pruebas Genéticas/métodos , Humanos , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Secuenciación Completa del Genoma/métodosAsunto(s)
Neoplasias de la Mama , Neoplasias , Humanos , Femenino , Neoplasias de la Mama/terapia , Proyectos Piloto , Queensland , Medicina de Precisión , MamaRESUMEN
Epithelial to mesenchymal transition (EMT) is a cellular phenotype switching phenomenon which occurs during normal development and is proposed to promote tumour cell invasive capabilities during tumour progression. Invasive lobular carcinoma (ILC) is a histological special type of breast cancer with a peculiar aetiology - the tumour cells display an invasive growth pattern, with detached, single cells or single files of cells, and a canonical feature is the loss of E-cadherin expression. These characteristics are indicative of an EMT or at the very least that they represent some plasticity between phenotypes. While some gene expression profiling data support this view, the tumour cells remain epithelial and limited immunohistochemistry data suggest that EMT markers may not feature prominently in ILC. We assessed the expression of a panel of EMT markers (fibronectin, vimentin, N-cadherin, smooth muscle actin, osteonectin, Snail, Twist) in 148 ILCs and performed a meta-analysis of publically available molecular data from 154 ILCs. Three out of 148 (2%) ILCs demonstrated an early and coordinated alteration of multiple EMT markers (down-regulation of E-cadherin, nuclear TWIST, and up-regulation of vimentin, osteonectin, and smooth muscle actin). However, the data overall do not support a role for EMT in defining the phenotypic peculiarities of the majority of ILCs. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Asunto(s)
Neoplasias de la Mama/patología , Carcinoma Lobular , Células Epiteliales/patología , Transición Epitelial-Mesenquimal/fisiología , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/metabolismo , Cadherinas/metabolismo , Carcinoma Lobular/genética , Carcinoma Lobular/metabolismo , Línea Celular Tumoral , Células Epiteliales/metabolismo , Femenino , Humanos , Inmunohistoquímica/métodos , Invasividad Neoplásica , Fenotipo , Factores de Transcripción/metabolismoRESUMEN
Brain metastases are highly-evolved manifestations of breast cancer arising in a unique microenvironment, giving them exceptional adaptability in the face of new extrinsic pressures. The incidence is rising in line with population ageing, and use of newer therapies that stabilise metastatic disease burden with variable efficacy throughout the body. Historically, there has been a widely-held view that brain metastases do not respond to circulating therapeutics because the blood-brain-barrier (BBB) restricts their uptake. However, emerging data are beginning to paint a more complex picture where the brain acts as a sanctuary for dormant, subclinical proliferations that are initially protected by the BBB, but then exposed to dynamic selection pressures as tumours mature and vascular permeability increases. Here, we review key experimental approaches and landmark studies that have charted the genomic landscape of breast cancer brain metastases. These findings are contextualised with the factors impacting on clonal outgrowth in the brain: intrinsic breast tumour cell capabilities required for brain metastatic fitness, and the neural niche, which is initially hostile to invading cells but then engineered into a tumour-support vehicle by the successful minority. We also discuss how late detection, abnormal vascular perfusion and interstitial fluid dynamics underpin the recalcitrant clinical behaviour of brain metastases, and outline active clinical trials in the context of precision management.
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Neoplasias Encefálicas/secundario , Neoplasias de la Mama/patología , Evolución Clonal , Neoplasias de la Mama/epidemiología , Femenino , Humanos , Modelos BiológicosRESUMEN
BACKGROUND: The complex interaction between multiple cell types and the microenvironment underlies the diverse pathways to carcinogenesis and necessitates sophisticated approaches to in vitro hypotheses testing. The combination of mixed culture format with high content immunofluorescence screening technology provides a powerful platform for observation of cell type specific behavior. METHODS: We have developed a versatile, high-throughput method for assessing cell-type specific responses. In addition to the specificity and sensitivity offered traditionally by immunofluorescent detection in flow cytometry, the 'in-cell' analysis method we describe provides the added benefits of higher throughput and the ability to analyse protein subcellular localisation in situ. Furthermore, elimination of the cell dissociation step allows for more immediate analysis of responses to specific extrinsic stimuli. We applied this method to investigate ionising radiation treatment response in normal breast epithelial cells, measuring growth rate, cell cycle response and double-strand DNA breaks. RESULTS: The 'in-cell' analysis approach elucidated several interesting donor and cell-type specific differences. Notably, in response to ionizing radiation we observed differential expression in luminal and basal-like cells of a member of the APOBEC enzyme family, recently identified as a critical driver of an oncogenic signature. Our findings suggest that this enzyme is active in the normal breast epithelium during DNA damage response. CONCLUSIONS: We demonstrate the practical application of a new method for assessing cell-type specific change in mixed cultures, especially the analysis of normal primary cultures, overcoming a major technical issue of dissecting the response of multiple cell types in a heterogeneous population.
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Neoplasias de la Mama/diagnóstico , Linaje de la Célula/genética , Separación Celular/métodos , Citometría de Flujo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Carcinogénesis/genética , Microambiente Celular/genética , Daño del ADN/genética , Células Epiteliales/metabolismo , Células Epiteliales/patología , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Radiación IonizanteRESUMEN
Our understanding of the natural history of breast cancer has evolved alongside technologies to study its genomic, transcriptomic, proteomic, and metabolomics landscapes. These technologies have helped decipher multiple molecular pathways dysregulated in breast cancer. First-generation 'omics analyses considered each of these dimensions individually, but it is becoming increasingly clear that more holistic, integrative approaches are required to fully understand complex biological systems. The 'omics represent an exciting era of discovery in breast cancer research, although important issues need to be addressed to realize the clinical utility of these data through precision cancer care. How can the data be applied to predict response to molecular-targeted therapies? When should treatment decisions be based on tumor genetics rather than histology? And with the sudden explosion of "big data" from large 'omics consortia and new precision clinical trials, how do we now negotiate evidence-based pathways to clinical translation through this apparent sea of opportunity? The aim of this review is to provide a broad overview of 'omics technologies used in breast cancer research today, the current state-of-play in terms of applying this new knowledge in the clinic, and the practical and ethical issues that will be central to the public discussion on the future of precision cancer care.
Asunto(s)
Neoplasias de la Mama , Genómica/tendencias , Metabolómica/tendencias , Proteómica/tendencias , Femenino , HumanosRESUMEN
Treatment options for patients with brain metastases (BMs) have limited efficacy and the mortality rate is virtually 100%. Targeted therapy is critically under-utilized, and our understanding of mechanisms underpinning metastatic outgrowth in the brain is limited. To address these deficiencies, we investigated the genomic and transcriptomic landscapes of 36 BMs from breast, lung, melanoma and oesophageal cancers, using DNA copy-number analysis and exome- and RNA-sequencing. The key findings were as follows. (a) Identification of novel candidates with possible roles in BM development, including the significantly mutated genes DSC2, ST7, PIK3R1 and SMC5, and the DNA repair, ERBB-HER signalling, axon guidance and protein kinase-A signalling pathways. (b) Mutational signature analysis was applied to successfully identify the primary cancer type for two BMs with unknown origins. (c) Actionable genomic alterations were identified in 31/36 BMs (86%); in one case we retrospectively identified ERBB2 amplification representing apparent HER2 status conversion, then confirmed progressive enrichment for HER2-positivity across four consecutive metastatic deposits by IHC and SISH, resulting in the deployment of HER2-targeted therapy for the patient. (d) In the ERBB/HER pathway, ERBB2 expression correlated with ERBB3 (r(2) = 0.496; p < 0.0001) and HER3 and HER4 were frequently activated in an independent cohort of 167 archival BM from seven primary cancer types: 57.6% and 52.6% of cases were phospho-HER3(Y1222) or phospho-HER4(Y1162) membrane-positive, respectively. The HER3 ligands NRG1/2 were barely detectable by RNAseq, with NRG1 (8p12) genomic loss in 63.6% breast cancer-BMs, suggesting a microenvironmental source of ligand. In summary, this is the first study to characterize the genomic landscapes of BM. The data revealed novel candidates, potential clinical applications for genomic profiling of resectable BMs, and highlighted the possibility of therapeutically targeting HER3, which is broadly over-expressed and activated in BMs, independent of primary site and systemic therapy.
Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundario , Perfilación de la Expresión Génica/métodos , Genómica/métodos , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/enzimología , Análisis Mutacional de ADN , Activación Enzimática , Amplificación de Genes , Dosificación de Gen , Regulación Neoplásica de la Expresión Génica , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Inmunohistoquímica , Ligandos , Terapia Molecular Dirigida , Mutación , Fenotipo , Fosforilación , Medicina de Precisión , Valor Predictivo de las Pruebas , Inhibidores de Proteínas Quinasas/uso terapéutico , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptor ErbB-3/genética , Receptor ErbB-3/metabolismo , Receptor ErbB-4/genética , Receptor ErbB-4/metabolismo , Microambiente TumoralRESUMEN
Invasive lobular carcinoma of the breast is the most common 'special' morphological subtype of breast cancer, comprising up to 15% of all cases. Tumours are generally of a good prognostic phenotype, being low histological grade and low mitotic index, hormone receptor positive and HER2, p53 and basal marker negative, and with a generally good response to endocrine therapy. Despite this, clinicians face countless challenges in the diagnosis and long-term management of patients, as they encounter a tumour that can be difficult to detect through screening, elicits a very invasive nature, a propensity for widespread metastatic colonisation and, consequently, in some studies a worse long-term poor outcome compared with invasive carcinoma of no special type. Here we review the morphological and molecular features that underpin the disparate biological and clinical characteristics of this fascinating tumour type.