RESUMO
PURPOSE OF REVIEW: In the last decade, poly (ADP-ribose) polymerase (PARP) inhibitors have been approved in the treatment of several cancers, such as breast and ovarian cancer. This article aims to discuss the current uses, limitations, and future directions for PARP inhibitors (PARPis) in the treatment of breast cancer. RECENT FINDINGS: Following the results of the OlympiAD and EMBRACA trials, PARPis were approved in HER2-negative breast cancer with a germline BRCA mutation. We reviewed this class of drugs' mechanism of action, efficacy, and limitations, as well as further studies that discussed resistance, impaired homologous recombination repair (HRR), and the combination of PARPis with other drugs. Improving understanding of HRR, increasing the ability to target resistance, and combining PARPis with other novel agents are continuing to increase the clinical utility of PARPis.
Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Feminino , Humanos , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Poli(ADP-Ribose) Polimerases/genética , Reparo do DNA , Neoplasias Ovarianas/tratamento farmacológicoRESUMO
PURPOSE OF REVIEW: Homologous recombination repair deficiency (HRD) increases breast cancer susceptibility and influences both prophylactic and active management of breast cancer. This review evaluates HRD testing and the therapeutic implications of HRD in a global context. RECENT FINDINGS: Ongoing research efforts have highlighted the importance of HRD beyond BRCA1/2 as a potential therapeutic target in breast cancer. However, despite the improved affordability of next-generation sequencing (NGS) and the discovery of PARP inhibitors, economic and geographical barriers in access to HRD testing and breast cancer screening do not allow all patients to benefit from the personalized treatment approach they provide. Advancements in HRD testing modalities and targeted therapeutics enable tailored breast cancer management. However, inequalities in access to testing and optimized treatments are contributing to widening health disparities globally.
Assuntos
Neoplasias da Mama , Reparo de DNA por Recombinação , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/diagnóstico , Feminino , Reparo de DNA por Recombinação/genética , Testes Genéticos/métodos , Detecção Precoce de Câncer/métodos , Predisposição Genética para Doença , Proteína BRCA2/genética , Proteína BRCA1/genética , Sequenciamento de Nucleotídeos em Larga EscalaRESUMO
BACKGROUND: Metastatic breast cancer is a major cause of cancer-related deaths in woman. Brain metastasis is a common and devastating site of relapse for several breast cancer molecular subtypes, including oestrogen receptor-positive disease, with life expectancy of less than a year. While efforts have been devoted to developing therapeutics for extra-cranial metastasis, drug penetration of blood-brain barrier (BBB) remains a major clinical challenge. Defining molecular alterations in breast cancer brain metastasis enables the identification of novel actionable targets. METHODS: Global transcriptomic analysis of matched primary and metastatic patient tumours (n = 35 patients, 70 tumour samples) identified a putative new actionable target for advanced breast cancer which was further validated in vivo and in breast cancer patient tumour tissue (n = 843 patients). A peptide mimetic of the target's natural ligand was designed in silico and its efficacy assessed in in vitro, ex vivo and in vivo models of breast cancer metastasis. RESULTS: Bioinformatic analysis of over-represented pathways in metastatic breast cancer identified ADAM22 as a top ranked member of the ECM-related druggable genome specific to brain metastases. ADAM22 was validated as an actionable target in in vitro, ex vivo and in patient tumour tissue (n = 843 patients). A peptide mimetic of the ADAM22 ligand LGI1, LGI1MIM, was designed in silico. The efficacy of LGI1MIM and its ability to penetrate the BBB were assessed in vitro, ex vivo and in brain metastasis BBB 3D biometric biohybrid models, respectively. Treatment with LGI1MIM in vivo inhibited disease progression, in particular the development of brain metastasis. CONCLUSION: ADAM22 expression in advanced breast cancer supports development of breast cancer brain metastasis. Targeting ADAM22 with a peptide mimetic LGI1MIM represents a new therapeutic option to treat metastatic brain disease.
Assuntos
Proteínas ADAM/metabolismo , Materiais Biomiméticos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/secundário , Neoplasias da Mama/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Peptídeos/farmacologia , Proteínas ADAM/biossíntese , Proteínas ADAM/genética , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Perfilação da Expressão Gênica , Humanos , Terapia de Alvo Molecular , Recidiva Local de Neoplasia/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genéticaRESUMO
6-Hydroxydopamine (6-OHDA), which is a neurotoxin that selectively destroys catecholaminergic nerves in sympathetically innervated tissues, has been used to provide a model of Parkinson's disease in experimental animals. It is rapidly autoxidised to yield potentially toxic products and reactive oxygen species. Its ability to release Fe(II) from protein storage sites also results in the formation of hROS. This account will consider how this family of toxic products may contribute to the observed effects of 6-OHDA.
Assuntos
Modelos Animais de Doenças , Neurotoxinas/farmacologia , Oxidopamina/farmacologia , Doença de Parkinson , Animais , Humanos , Neurotoxinas/toxicidade , Oxidopamina/toxicidadeRESUMO
BACKGROUND: Breast cancer brain metastasis is a rising occurrence, necessitating a better understanding of the mechanisms involved for effective management. Breast cancer brain metastases diverge notably from the primary tumor, with gains in kinase and concomitant losses of steroid signaling observed. In this study, we explored the role of the kinase receptor RET in promoting breast cancer brain metastases and provide a rationale for targeting this receptor. METHODS: RET expression was characterized in a cohort of patients with primary and brain metastatic tumors. RET functionality was assessed using pharmacological inhibition and gene silencing in patient-derived brain metastatic tumor explants and in vivo models, organoid models, and brain organotypic cultures. RNA sequencing was used to uncover novel brain metastatic relevant RET mechanisms of action. RESULTS: A statistically significant enrichment of RET in brain metastases was observed in estrogen receptor-positive breast cancer, where it played a role in promoting cancer cell adhesion, survival, and outgrowth in the brain. In vivo, RET overexpression enhanced brain metastatic competency in patient-derived models. At a mechanistic level, RET overexpression was found to enhance the activation of gene programs involved in cell adhesion, requiring EGFR cooperation to deliver a pro-brain metastatic phenotype. CONCLUSION: Our results illustrate, for the first time, the role of RET in regulating colonization and outgrowth of breast cancer brain metastasis and provide data to support the use of RET inhibitors in the management strategy for patients with breast cancer brain metastases.
RESUMO
Glucocorticoid receptor (GR) is a transcription factor that plays a crucial role in cancer biology. In this study, we utilized an in silico-designed GR activity signature to demonstrate that GR relates to the proliferative capacity of numerous primary cancer types. In breast cancer, the GR activity status determines luminal subtype identity and has implications for patient outcomes. We reveal that GR engages with estrogen receptor (ER), leading to redistribution of ER on the chromatin. Notably, GR activation leads to upregulation of the ZBTB16 gene, encoding for a transcriptional repressor, which controls growth in ER-positive breast cancer and associates with prognosis in luminal A patients. In relation to ZBTB16's repressive nature, GR activation leads to epigenetic remodeling and loss of histone acetylation at sites proximal to cancer-driving genes. Based on these findings, epigenetic inhibitors reduce viability of ER-positive breast cancer cells that display absence of GR activity. Our findings provide insights into how GR controls ER-positive breast cancer growth and may have implications for patients' prognostication and provide novel therapeutic candidates for breast cancer treatment.
Assuntos
Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismoRESUMO
The so-called reactive oxygen species (ROS) are defined as oxygen-containing species that are more reactive than O(2) itself, which include hydrogen peroxide and superoxide. Although these are quite stable, they may be converted in the presence of transition metal ions, such as Fe(II), to the highly reactive oxygen species (hROS). hROS may exist as free hydroxyl radicals (HO·), as bound ("crypto") radicals or as Fe(IV)-oxo (ferryl) species and the somewhat less reactive, non-radical species, singlet oxygen. This review outlines the processes by which hROS may be formed, their damaging potential, and the evidence that they might have signaling functions. Since our understanding of the formation and actions of hROS depends on reliable procedures for their detection, particular attention is given to procedures for hROS detection and quantitation and their applicability to in vivo studies.
Assuntos
Espécies Reativas de Oxigênio/química , Radicais Livres , Ferro , Espécies Reativas de Oxigênio/metabolismo , Oxigênio Singlete , Elementos de Transição/químicaRESUMO
Obesity is highly prevalent in breast cancer patients and is associated with increased recurrence and breast cancer-specific mortality. Glucocorticoids (GC) are used as an adjuvant in cancer treatment and are associated with promoting breast cancer metastasis through activation of stemness-related pathways. Therefore, we utilized the synergetic allograft E0771 breast cancer model to investigate if treatment with GCs had differential effects on promoting cancer stem cells in lean and diet-induced obese mice. Indeed, both lean mice treated with dexamethasone and obese mice with no treatment had no effect on the ex vivo colony-forming ability, mammosphere formation, or aldehyde dehydrogenase (ALDH) bright subpopulation. However, treatment of obese mice with dexamethasone resulted in a significant increase in ex vivo colony formation, mammosphere formation, ALDH bright subpopulation, and expression of pluripotency transcription factors. GC transcriptionally regulated genes were not altered in the dexamethasone-treated groups compared to treatment controls. In summary, these results provide initial evidence that obesity presents a higher risk of GC-induced cancer stemness via non-genomic GC signaling which is of potential translational significance.
Assuntos
Neoplasias da Mama , Aldeído Desidrogenase/metabolismo , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Dexametasona/farmacologia , Feminino , Humanos , Camundongos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Obesidade/metabolismoRESUMO
The molecular events and transcriptional plasticity driving brain metastasis in clinically relevant breast tumor subtypes has not been determined. Here we comprehensively dissect genomic, transcriptomic and clinical data in patient-matched longitudinal tumor samples, and unravel distinct transcriptional programs enriched in brain metastasis. We report on subtype specific hub genes and functional processes, central to disease-affected networks in brain metastasis. Importantly, in luminal brain metastases we identify homologous recombination deficiency operative in transcriptomic and genomic data with recurrent breast mutational signatures A, F and K, associated with mismatch repair defects, TP53 mutations and homologous recombination deficiency (HRD) respectively. Utilizing PARP inhibition in patient-derived brain metastatic tumor explants we functionally validate HRD as a key vulnerability. Here, we demonstrate a functionally relevant HRD evident at genomic and transcriptomic levels pointing to genomic instability in breast cancer brain metastasis which is of potential translational significance.
Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Metástase Neoplásica , Adulto , Mama , Feminino , Redes Reguladoras de Genes , Genes p53/genética , Humanos , Pessoa de Meia-Idade , Mutação , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , TranscriptomaRESUMO
Whole-brain radiotherapy (WBRT) is the treatment backbone for many patients with brain metastasis; however, its efficacy in preventing disease progression and the associated toxicity have questioned the clinical impact of this approach and emphasized the need for alternative treatments. Given the limited therapeutic options available for these patients and the poor understanding of the molecular mechanisms underlying the resistance of metastatic lesions to WBRT, we sought to uncover actionable targets and biomarkers that could help to refine patient selection. Through an unbiased analysis of experimental in vivo models of brain metastasis resistant to WBRT, we identified activation of the S100A9-RAGE-NF-κB-JunB pathway in brain metastases as a potential mediator of resistance in this organ. Targeting this pathway genetically or pharmacologically was sufficient to revert the WBRT resistance and increase therapeutic benefits in vivo at lower doses of radiation. In patients with primary melanoma, lung or breast adenocarcinoma developing brain metastasis, endogenous S100A9 levels in brain lesions correlated with clinical response to WBRT and underscored the potential of S100A9 levels in the blood as a noninvasive biomarker. Collectively, we provide a molecular framework to personalize WBRT and improve its efficacy through combination with a radiosensitizer that balances therapeutic benefit and toxicity.
Assuntos
Neoplasias Encefálicas , Melanoma , Neoplasias Encefálicas/secundário , Irradiação Craniana , Humanos , Melanoma/radioterapiaRESUMO
We report a medium-throughput drug-screening platform (METPlatform) based on organotypic cultures that allows to evaluate inhibitors against metastases growing in situ. By applying this approach to the unmet clinical need of brain metastasis, we identified several vulnerabilities. Among them, a blood-brain barrier permeable HSP90 inhibitor showed high potency against mouse and human brain metastases at clinically relevant stages of the disease, including a novel model of local relapse after neurosurgery. Furthermore, in situ proteomic analysis applied to metastases treated with the chaperone inhibitor uncovered a novel molecular program in brain metastasis, which includes biomarkers of poor prognosis and actionable mechanisms of resistance. Our work validates METPlatform as a potent resource for metastasis research integrating drug-screening and unbiased omic approaches that is compatible with human samples. Thus, this clinically relevant strategy is aimed to personalize the management of metastatic disease in the brain and elsewhere.
Assuntos
Antineoplásicos , Neoplasias Encefálicas , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Barreira Hematoencefálica , Neoplasias Encefálicas/tratamento farmacológico , Camundongos , Recidiva Local de Neoplasia , ProteômicaRESUMO
Steroid regulated cancer cells use nuclear receptors and associated regulatory proteins to orchestrate transcriptional networks to drive disease progression. In primary breast cancer, the coactivator AIB1 promotes estrogen receptor (ER) transcriptional activity to enhance cell proliferation. The function of the coactivator in ER+ metastasis however is not established. Here we describe AIB1 as a survival factor, regulator of pro-metastatic transcriptional pathways and a promising actionable target. Genomic alterations and functional expression of AIB1 associated with reduced disease-free survival in patients and enhanced metastatic capacity in novel CDX and PDX ex-vivo models of ER+ metastatic disease. Comparative analysis of the AIB1 interactome with complementary RNAseq characterized AIB1 as a transcriptional repressor. Specifically, we report that AIB1 interacts with MTA2 to form a repressive complex, inhibiting CDH1 (encoding E-cadherin) to promote EMT and drive progression. We further report that pharmacological and genetic inhibition of AIB1 demonstrates significant anti-proliferative activity in patient-derived models establishing AIB1 as a viable strategy to target endocrine resistant metastasis. This work defines a novel role for AIB1 in the regulation of EMT through transcriptional repression in advanced cancer cells with a considerable implication for prognosis and therapeutic interventions.
Assuntos
Neoplasias da Mama/tratamento farmacológico , Caderinas/genética , Histona Desacetilases/genética , Coativador 3 de Receptor Nuclear/genética , Proteínas Repressoras/genética , Antígenos CD/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células/genética , Intervalo Livre de Doença , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Metástase Neoplásica , Coativador 3 de Receptor Nuclear/antagonistas & inibidores , Fenótipo , Prognóstico , Tamoxifeno/farmacologiaRESUMO
Fixed-tissue ChIP-seq for H3K27 acetylation (H3K27ac) profiling (FiTAc-seq) is an epigenetic method for profiling active enhancers and promoters in formalin-fixed, paraffin-embedded (FFPE) tissues. We previously developed a modified ChIP-seq protocol (FiT-seq) for chromatin profiling in FFPE. FiT-seq produces high-quality chromatin profiles particularly for methylated histone marks but is not optimized for H3K27ac profiling. FiTAc-seq is a modified protocol that replaces the proteinase K digestion applied in FiT-seq with extended heating at 65 °C in a higher concentration of detergent and a minimized sonication step, to produce robust genome-wide H3K27ac maps from clinical samples. FiTAc-seq generates high-quality enhancer landscapes and super-enhancer (SE) annotation in numerous archived FFPE samples from distinct tumor types. This approach will be of great interest for both basic and clinical researchers. The entire protocol from FFPE blocks to sequence-ready library can be accomplished within 4 d.
Assuntos
Sequenciamento de Cromatina por Imunoprecipitação/métodos , Histonas/química , Histonas/metabolismo , Lisina/metabolismo , Inclusão em Parafina , Fixação de Tecidos , Acetilação , Animais , Fígado/citologia , CamundongosRESUMO
Spread of cancer to the brain remains an unmet clinical need in spite of the increasing number of cases among patients with lung, breast cancer, and melanoma most notably. Although research on brain metastasis was considered a minor aspect in the past due to its untreatable nature and invariable lethality, nowadays, limited but encouraging examples have questioned this statement, making it more attractive for basic and clinical researchers. Evidences of its own biological identity (i.e., specific microenvironment) and particular therapeutic requirements (i.e., presence of blood-brain barrier, blood-tumor barrier, molecular differences with the primary tumor) are thought to be critical aspects that must be functionally exploited using preclinical models. We present the coordinated effort of 19 laboratories to compile comprehensive information related to brain metastasis experimental models. Each laboratory has provided details on the cancer cell lines they have generated or characterized as being capable of forming metastatic colonies in the brain, as well as principle methodologies of brain metastasis research. The Brain Metastasis Cell Lines Panel (BrMPanel) represents the first of its class and includes information about the cell line, how tropism to the brain was established, and the behavior of each model in vivo. These and other aspects described are intended to assist investigators in choosing the most suitable cell line for research on brain metastasis. The main goal of this effort is to facilitate research on this unmet clinical need, to improve models through a collaborative environment, and to promote the exchange of information on these valuable resources.
Assuntos
Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Neoplasias Experimentais/patologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Humanos , Camundongos , Ratos , Tropismo , Microambiente Tumoral , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Divergent roles for androgen receptor (AR) in breast cancer have been reported. Following aromatase inhibitor (AI) treatment, the conversion of circulating androgens into estrogens can be diminished by >99%. We wished to establish whether the steroid environment can dictate the role of AR and the implications of this for subsequent therapy. This study utilizes models of AI resistance to explore responsiveness to PI3K/mTOR and anti-AR therapy when cells are exposed to unconverted weak androgens. Transcriptomic alterations driven by androstenedione (4AD) were assessed by RNA-sequencing. AR and estrogen receptor (ER) recruitment to target gene promoters was evaluated using ChIP, and relevance to patient profiles was performed using publicly available data sets. Although BEZ235 showed decreased viability across AI-sensitive and -resistant cell lines, anti-AR treatment elicited a decrease in cell viability only in the AI-resistant model. Serum and glucocorticoid-regulated kinase 3 (SGK3) and cAMP-dependent protein kinase inhibitor ß (PKIB) were confirmed to be regulated by 4AD and shown to be mediated by AR; crucially, reexposure to estradiol suppressed expression of these genes. Meta-analysis of transcript levels showed high expression of SGK3 and PKIB to be associated with poor response to endocrine therapy (HR = 2.551, P = 0.003). Furthermore, this study found levels of SGK3 to be sustained in patients who do not respond to AI therapy. This study highlights the importance of the tumor steroid environment. SGK3 and PKIB are associated with poor response to endocrine therapy and could have utility in tailoring therapeutic approaches.
Assuntos
Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Receptores Androgênicos/metabolismo , Esteroides/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Androstenodiona/farmacologia , Inibidores da Aromatase/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Intervalo Livre de Doença , Resistencia a Medicamentos Antineoplásicos/genética , Estradiol/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imidazóis/farmacologia , Imidazóis/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células MCF-7 , Fosfatidilinositol 3-Quinases/metabolismo , Pós-Menopausa/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Proteínas Serina-Treonina Quinases/metabolismo , Quinolinas/farmacologia , Quinolinas/uso terapêutico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Estrogênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética , Regulação para Cima/efeitos dos fármacosRESUMO
Breast cancer brain metastasis (BCBM) is an area of unmet clinical need. MicroRNAs (miRNAs) have been linked to the metastatic process in breast cancer (BC). In this study, we aim to determine differentially-expressed miRNAs utilising primary BCs that did not relapse (BCNR, n = 12), primaries that relapsed (BCR) and their paired (n = 40 pairs) brain metastases (BM) using the NanoString™ nCounter™ miRNA Expression Assays. Significance analysis of microarrays identified 58 and 11 differentially-expressed miRNAs between BCNR vs BCR and BCR vs BM respectively and pathway analysis revealed enrichment for genes involved in invasion and metastasis. Four miRNAs, miR-132-3p, miR-199a-5p, miR-150-5p and miR-155-5p, were differentially-expressed within both cohorts (BCNR-BCR, BCR-BM) and receiver-operating characteristic curve analysis (p = 0.00137) and Kaplan-Meier survival method (p = 0.0029, brain metastasis-free survival; p = 0.0007, overall survival) demonstrated their potential use as prognostic markers. Ingenuity pathway enrichment linked them to the MET oncogene, and the cMET protein was overexpressed in the BCR (p < 0.0001) and BM (p = 0.0008) cases, compared to the BCNRs. The 4-miRNAs panel identified in this study could be potentially used to distinguish BC patients with an increased risk of developing BCBM and provide potential novel therapeutic targets, whereas cMET-targeting warrants further investigation in the treatment of BCBM.
Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Neoplasias da Mama/mortalidade , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/secundário , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Perfilação da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Invasividade Neoplásica , Recidiva Local de Neoplasia , Distribuição Normal , Análise de Sequência com Séries de Oligonucleotídeos , Análise de Componente Principal , Prognóstico , Curva ROC , Risco , Resultado do TratamentoRESUMO
PURPOSE: Invasive lobular carcinoma (ILC) is a subtype of breast cancer accounting for 10% of breast tumors. The majority of patients are treated with endocrine therapy; however, endocrine resistance is common in estrogen receptor-positive breast cancer and new therapeutic strategies are needed. Bromodomain and extraterminal inhibitors (BETi) are effective in diverse types of breast cancer but they have not yet been assessed in ILC. EXPERIMENTAL DESIGN: We assessed whether targeting the BET proteins with JQ1 could serve as an effective therapeutic strategy in ILC in both 2D and 3D models. We used dynamic BH3 profiling and RNA-sequencing (RNA-seq) to identify transcriptional reprograming enabling resistance to JQ1-induced apoptosis. As part of the RATHER study, we obtained copy-number alterations and RNA-seq on 61 ILC patient samples. RESULTS: Certain ILC cell lines were sensitive to JQ1, while others were intrinsically resistant to JQ1-induced apoptosis. JQ1 treatment led to an enhanced dependence on antiapoptotic proteins and a transcriptional rewiring inducing fibroblast growth factor receptor 1 (FGFR1). This increase in FGFR1 was also evident in invasive ductal carcinoma (IDC) cell lines. The combination of JQ1 and FGFR1 inhibitors was highly effective at inhibiting growth in both 2D and 3D models of ILC and IDC. Interestingly, we found in the RATHER cohort of 61 ILC patients that 20% had FGFR1 amplification and we showed that high BRD3 mRNA expression was associated with poor survival specifically in ILC. CONCLUSIONS: We provide evidence that BETi either alone or in combination with FGFR1 inhibitors or BH3 mimetics may be a useful therapeutic strategy for recurrent ILC patients.
Assuntos
Compostos de Anilina/farmacologia , Antineoplásicos/farmacologia , Azepinas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Carcinoma Lobular/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Sulfonamidas/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Triazóis/farmacologia , Apoptose , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Lobular/metabolismo , Carcinoma Lobular/patologia , Ciclo Celular , Proliferação de Células , Estudos de Coortes , Feminino , Humanos , Invasividade Neoplásica , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Taxa de Sobrevida , Células Tumorais CultivadasRESUMO
BACKGROUND: Breast cancer brain metastases (BrMs) are defined by complex adaptations to both adjuvant treatment regimens and the brain microenvironment. Consequences of these alterations remain poorly understood, as does their potential for clinical targeting. We utilized genome-wide molecular profiling to identify therapeutic targets acquired in metastatic disease. METHODS: Gene expression profiling of 21 patient-matched primary breast tumors and their associated brain metastases was performed by TrueSeq RNA-sequencing to determine clinically actionable BrM target genes. Identified targets were functionally validated using small molecule inhibitors in a cohort of resected BrM ex vivo explants (n = 4) and in a patient-derived xenograft (PDX) model of BrM. All statistical tests were two-sided. RESULTS: Considerable shifts in breast cancer cell-specific gene expression profiles were observed (1314 genes upregulated in BrM; 1702 genes downregulated in BrM; DESeq; fold change > 1.5, Padj < .05). Subsequent bioinformatic analysis for readily druggable targets revealed recurrent gains in RET expression and human epidermal growth factor receptor 2 (HER2) signaling. Small molecule inhibition of RET and HER2 in ex vivo patient BrM models (n = 4) resulted in statistically significantly reduced proliferation (P < .001 in four of four models). Furthermore, RET and HER2 inhibition in a PDX model of BrM led to a statistically significant antitumor response vs control (n = 4, % tumor growth inhibition [mean difference; SD], anti-RET = 86.3% [1176; 258.3], P < .001; anti-HER2 = 91.2% [1114; 257.9], P < .01). CONCLUSIONS: RNA-seq profiling of longitudinally collected specimens uncovered recurrent gene expression acquisitions in metastatic tumors, distinct from matched primary tumors. Critically, we identify aberrations in key oncogenic pathways and provide functional evidence for their suitability as therapeutic targets. Altogether, this study establishes recurrent, acquired vulnerabilities in BrM that warrant immediate clinical investigation and suggests paired specimen expression profiling as a compelling and underutilized strategy to identify targetable dependencies in advanced cancers.
Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Recidiva Local de Neoplasia/genética , Transcriptoma , Adulto , Animais , Neoplasias Encefálicas/secundário , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Feminino , Seguimentos , Perfilação da Expressão Gênica , Humanos , Estudos Longitudinais , Camundongos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Prognóstico , Taxa de Sobrevida , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Elevated levels of the anti-apoptotic BCL2 protein associate with favourable outcome in breast cancer. We investigated whether executioner caspase activation downstream of mitochondrial apoptosis was associated with, or independent, of BCL2's prognostic signature in breast cancer. Levels of pro- and anti-apoptotic BCL2 family proteins were quantified in triple negative breast cancer (TNBC) samples and utilised to calculate BCL2 profiles of 845 breast cancer patients. Biomarkers including single apoptosis proteins and network-enriched apoptosis system signatures were evaluated using uni- and multi-variate Cox-models. In both TNBC and non-TNBC breast cancer, the anti-apoptotic BCL2 protein was particularly abundant when compared to other solid tumours. High BCL2 protein levels were prognostic of favourable outcome across all breast cancers (HR 0.4, 95% CI 0.2-0.6, Wald p < 0.0001). Although BCL2 and cleaved caspase-7 levels were negatively correlated, levels of cleaved caspase-7 were also associated with favourable outcome (HR 0.4, 95% CI 0.3-0.7, Wald p = 0.001). A combination of low BCL2 and low cleaved caspase-7 protein levels was highly prognostic of unfavourable outcome across all breast cancers (HR 11.29, 95% CI 2.20-58.23, Wald p = 0.01). A combination of BCL2 and cleaved caspase-7 levels is a promising prognostic biomarker in breast cancer patients. KEY MESSAGE: BCL2 levels are elevated in breast cancer where they are marker of good prognosis. BCL2 and active caspase levels correlate negatively; yet, active caspases indicate good outcome. Low BCL2 and low caspase-7 are highly prognostic of unfavourable outcome across all breast cancers. BCL2 levels indicate molecular subtype and tumour proliferation status in breast cancer.