RESUMO
Targeting cell surface molecules using radioligand and antibody-based therapies has yielded considerable success across cancers. However, it remains unclear how the expression of putative lineage markers, particularly cell surface molecules, varies in the process of lineage plasticity, wherein tumor cells alter their identity and acquire new oncogenic properties. A notable example of lineage plasticity is the transformation of prostate adenocarcinoma (PRAD) to neuroendocrine prostate cancer (NEPC)-a growing resistance mechanism that results in the loss of responsiveness to androgen blockade and portends dismal patient survival. To understand how lineage markers vary across the evolution of lineage plasticity in prostate cancer, we applied single-cell analyses to 21 human prostate tumor biopsies and two genetically engineered mouse models, together with tissue microarray analysis on 131 tumor samples. Not only did we observe a higher degree of phenotypic heterogeneity in castrate-resistant PRAD and NEPC than previously anticipated but also found that the expression of molecules targeted therapeutically, namely PSMA, STEAP1, STEAP2, TROP2, CEACAM5, and DLL3, varied within a subset of gene-regulatory networks (GRNs). We also noted that NEPC and small cell lung cancer subtypes shared a set of GRNs, indicative of conserved biologic pathways that may be exploited therapeutically across tumor types. While this extreme level of transcriptional heterogeneity, particularly in cell surface marker expression, may mitigate the durability of clinical responses to current and future antigen-directed therapies, its delineation may yield signatures for patient selection in clinical trials, potentially across distinct cancer types.
Assuntos
Análise de Célula Única , Masculino , Humanos , Análise de Célula Única/métodos , Animais , Camundongos , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Antígenos de Superfície/metabolismo , Antígenos de Superfície/genética , Antígenos de Neoplasias/metabolismo , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma/metabolismo , Adenocarcinoma/tratamento farmacológico , Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/patologia , Carcinoma Neuroendócrino/metabolismo , Carcinoma Neuroendócrino/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológicoRESUMO
The recent movement toward returning individual research results to study subjects/participants generates ethical and legal challenges for laboratories performing research on human biospecimens. The concept of an individual's interest in knowing the results of testing on their tissue is pitted against individual and systemic risks and an established legal framework regulating the performance of laboratory testing for medical care purposes. This article discusses the rationale for returning individual research results to subjects, the potential risks associated with returning these results, and the legal framework in the United States that governs testing of identifiable human biospecimens. On the basis of these considerations, this article provides recommendations for investigators to consider when planning and executing human biospecimen research, with the objective of appropriately balancing the interests of research subjects, the need for ensuring integrity of the research process, and compliance with US laws and regulations.
Assuntos
Pesquisa Biomédica/ética , Humanos , Estados UnidosRESUMO
BACKGROUND: Prostate cancer (PCa) is diagnosed at the highest rate of all non-cutaneous male cancers in the United States. The androgen-dependent (AD) transcription factor, androgen receptor (AR), drives PCa-but inhibiting AR or androgen biosynthesis induces remission for only a short time. At which point, patients acquire more aggressive castration-resistant (CR) disease with re-activated AR-dependent signaling. To combat treatment resistance, down-regulating AR protein expression has been considered as a potential treatment strategy for CR-PCa. METHODS: AD- and CR-PCa cell lines were treated with the well-tolerated FDA-approved oral medicine, riluzole. Expression of full-length or wild-type AR (AR-FL) and constitutively active AR-splice variant 7 (AR-V7) was assessed by immunoblotting. AR-FL/AR-V7 activity was measured using qRT-PCR of AR-target genes. Cytoplasmic [Ca2+ ] levels were measured using a fluorescent Ca2+ indicator microplate assay. Markers of the endoplasmic reticulum stress (ERS) pathway and autophagy were assessed by immunoblotting. Direct interaction between AR and selective autophagy receptor p62 was demonstrated by co-immunoprecipitation. RESULTS: We demonstrate that riluzole downregulates AR-FL, mutant ARs, and AR-V7 proteins expression by protein degradation through ERS pathway and selective autophagy. Riluzole also significantly inhibited AR transcription activity by decreasing its target genes expression (PSA, TMPRSS2, and KLK2). CONCLUSIONS: We provide key mechanistic insights by which riluzole exerts its anti-tumorigenic effects and induces AR protein degradation via ERS pathways. Our findings support the potential utility of riluzole for treatment of PCa.
Assuntos
Androgênios/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Receptores Androgênicos/metabolismo , Riluzol/farmacologia , Fator 6 Ativador da Transcrição/metabolismo , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Interações Medicamentosas , Endorribonucleases/antagonistas & inibidores , Endorribonucleases/metabolismo , Humanos , Masculino , Neoplasias da Próstata/metabolismo , Neoplasias de Próstata Resistentes à Castração/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Receptores Androgênicos/biossíntese , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia , Tiofenos/farmacologiaRESUMO
The balance between adaptive and innate immunity in kidney damage in salt-dependent hypertension is unclear. We investigated early renal dysfunction and the influence of Axl, a receptor tyrosine kinase, on innate immune response in hypertensive kidney in mice with lymphocyte deficiency (Rag1-/-). The data suggest that increased presence of CD11b+ myeloid cells in the medulla might explain intensified salt and water retention as well as initial hypertensive response in Rag1-/- mice. Global deletion of Axl on Rag1-/- background reversed kidney dysfunction and accumulation of myeloid cells in the kidney medulla. Chimeric mice that lack Axl in innate immune cells (in the absence of lymphocytes) significantly improved kidney function and abolished early hypertensive response. The bioinformatics analyses of Axl-related gene-gene interaction networks established tissue-specific variation in regulatory pathways. It was confirmed that complement C3 is important for Axl-mediated interactions between myeloid and vascular cells in hypertensive kidney. In summary, innate immunity is crucial for renal dysfunction in early hypertension, and is highly influenced by the presence of Axl.
Assuntos
Hipertensão/imunologia , Imunidade Inata/imunologia , Nefropatias/imunologia , Linfócitos/imunologia , Proteínas Proto-Oncogênicas/fisiologia , Receptores Proteína Tirosina Quinases/fisiologia , Animais , Células Cultivadas , Complemento C3/metabolismo , Proteínas de Homeodomínio/fisiologia , Hipertensão/metabolismo , Hipertensão/patologia , Nefropatias/metabolismo , Nefropatias/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais , Receptor Tirosina Quinase AxlRESUMO
OBJECTIVE: Survival of immune and nonimmune cells relies on Axl, a receptor tyrosine kinase, which is implicated in hypertension. Activated T lymphocytes are involved in regulation of high blood pressure. The goal of the study was to investigate the role of Axl in T-lymphocyte functions and its contribution to salt-dependent hypertension. APPROACH AND RESULTS: We report increased apoptosis in peripheral blood from Axl(-/-) mice because of lower numbers of white blood cells mostly lymphocytes. In vitro studies showed modest reduction in interferon gamma production in Axl(-/-) type 1 T helper cells. Axl did not affect basic proliferation capacity or production of interleukin 4 in Axl(-/-) type 2 T helper cells. However, competitive repopulation of Axl(-/-) bone marrow or adoptive transfer of Axl(-/-) CD4(+) T cells to Rag1(-/-) mice showed robust effect of Axl on T lymphocyte expansion in vivo. Adoptive transfer of Axl(-/-) CD4(+) T cells was protective in a later phase of deoxycorticosterone-acetate and salt hypertension. Reduced numbers of CD4(+) T cells in circulation and in perivascular adventitia decreased vascular remodeling and increased vascular apoptosis in the late phase of hypertension. CONCLUSIONS: These findings suggest that Axl is critical for survival of T lymphocytes, especially during vascular remodeling in hypertension.
Assuntos
Apoptose , Pressão Sanguínea , Linfócitos T CD4-Positivos/enzimologia , Hipertensão/enzimologia , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Cloreto de Sódio na Dieta , Transferência Adotiva , Animais , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/transplante , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Acetato de Desoxicorticosterona , Modelos Animais de Doenças , Genótipo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Hipertensão/genética , Hipertensão/patologia , Hipertensão/fisiopatologia , Interferon gama/metabolismo , Interleucina-4/metabolismo , Ativação Linfocitária , Masculino , Camundongos Knockout , Fenótipo , Proteínas Proto-Oncogênicas/deficiência , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/deficiência , Receptores Proteína Tirosina Quinases/genética , Transdução de Sinais , Fatores de Tempo , Remodelação Vascular , Receptor Tirosina Quinase AxlRESUMO
Recent studies implicate the muscle-specific ubiquitin ligase muscle RING finger-1 (MuRF1) in inhibiting pathological cardiomyocyte growth in vivo by inhibiting the transcription factor SRF. These studies led us to hypothesize that MuRF1 similarly inhibits insulin-like growth factor-I (IGF-I)-mediated physiological cardiomyocyte growth. We identified two lines of evidence to support this hypothesis: IGF-I stimulation of cardiac-derived cells with MuRF1 knockdown 1) exhibited an exaggerated hypertrophy and, 2) conversely, increased MuRF1 expression-abolished IGF-I-dependent cardiomyocyte growth. Enhanced hypertrophy with MuRF1 knockdown was accompanied by increases in Akt-regulated gene expression. Unexpectedly, MuRF1 inhibition of this gene expression profile was not a result of differences in p-Akt. Instead, we found that MuRF1 inhibits total protein levels of Akt, GSK-3ß (downstream of Akt), and mTOR while limiting c-Jun protein expression, a mechanism recently shown to govern Akt, GSK-3ß, and mTOR activities and expression. These findings establish that MuRF1 inhibits IGF-I signaling by restricting c-Jun activity, a novel mechanism recently identified in the context of ischemia-reperfusion injury. Since IGF-I regulates exercise-mediated physiological cardiac growth, we challenged MuRF1(-/-) and MuRF1-Tg+ mice and their wild-type sibling controls to 5 wk of voluntary wheel running. MuRF1(-/-) cardiac growth was increased significantly over wild-type control; conversely, the enhanced exercise-induced cardiac growth was lost in MuRF1-Tg+ animals. These studies demonstrate that MuRF1-dependent attenuation of IGF-I signaling via c-Jun is applicable in vivo and establish that further understanding of this novel mechanism may be crucial in the development of therapies targeting IGF-I signaling.
Assuntos
Fator de Crescimento Insulin-Like I/farmacologia , Sistema de Sinalização das MAP Quinases , Proteínas Musculares/fisiologia , Miócitos Cardíacos/patologia , Ubiquitina-Proteína Ligases/fisiologia , Animais , Animais Recém-Nascidos , Cardiomegalia/genética , Cardiomegalia/metabolismo , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Feminino , Hipertrofia/genética , Hipertrofia/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Miócitos Cardíacos/efeitos dos fármacos , Proteínas com Motivo TripartidoRESUMO
AIMS: Muscle ring finger (MuRF) proteins have been implicated in the transmission of mechanical forces to nuclear cell signaling pathways through their association with the sarcomere. We recently reported that MuRF1, but not MuRF2, regulates pathologic cardiac hypertrophy in vivo. This was surprising given that MuRF1 and MuRF2 interact with each other and many of the same sarcomeric proteins experimentally. METHODS AND RESULTS: Mice missing all four MuRF1 and MuRF2 alleles [MuRF1/MuRF2 double null (DN)] were born with a massive spontaneous hypertrophic cardiomyopathy and heart failure; mice that were null for one of the genes but heterozygous for the other (i.e. MuRF1(-/-) //MuRF2(+/-) or MuRF1(+/-) //MuRF2(-/-) ) were phenotypically identical to wild-type mice. Microarray analysis of genes differentially-expressed between MuRF1/MuRF2 DN, mice missing three of the four alleles and wild-type mice revealed a significant enrichment of genes regulated by the E2F transcription factor family. More than 85% of the differentially-expressed genes had E2F promoter regions (E2f:DP; P<0.001). Western analysis of E2F revealed no differences between MuRF1/MuRF2 DN hearts and wild-type hearts; however, chromatin immunoprecipitation studies revealed that MuRF1/MuRF2 DN hearts had significantly less binding of E2F1 in the promoter regions of genes previously defined to be regulated by E2F1 (p21, Brip1 and PDK4, P<0.01). CONCLUSIONS: These studies suggest that MuRF1 and MuRF2 play a redundant role in regulating developmental physiologic hypertrophy, by regulating E2F transcription factors essential for normal cardiac development by supporting E2F localization to the nucleus, but not through a process that degrades the transcription factor.
Assuntos
Cardiomegalia/metabolismo , Coração/fisiologia , Proteínas Musculares/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Animais Recém-Nascidos , Cardiomegalia/genética , Fator de Transcrição E2F1/genética , Fator de Transcrição E2F1/metabolismo , Expressão Gênica , Coração/crescimento & desenvolvimento , Camundongos , Camundongos Knockout , Proteínas Musculares/genética , Regiões Promotoras Genéticas , Sarcômeros/metabolismo , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases/genéticaRESUMO
Notch signaling can have either an oncogenic or tumor suppressive function in cancer depending on the cancer type and cellular context. While Notch can be oncogenic in early prostate cancer, we identified significant downregulation of the Notch pathway during prostate cancer progression from adenocarcinoma to neuroendocrine prostate cancer where it functions as a tumor suppressor. Activation of Notch in neuroendocrine and Rb1/Trp53-deficient prostate cancer models led to phenotypic conversion towards a more indolent non-neuroendocrine state with glandular features and expression of luminal lineage markers. This was accompanied by up-regulation of MHC and type I interferon and immune cell infiltration. Overall, these data support Notch signaling as a suppressor of neuroendocrine differentiation in advanced prostate cancer and provides insights into how Notch signaling influences lineage plasticity and the tumor microenvironment.
RESUMO
Targeting cell surface molecules using radioligand and antibody-based therapies has yielded considerable success across cancers. However, it remains unclear how the expression of putative lineage markers, particularly cell surface molecules, varies in the process of lineage plasticity, wherein tumor cells alter their identity and acquire new oncogenic properties. A notable example of lineage plasticity is the transformation of prostate adenocarcinoma (PRAD) to neuroendocrine prostate cancer (NEPC)--a growing resistance mechanism that results in the loss of responsiveness to androgen blockade and portends dismal patient survival. To understand how lineage markers vary across the evolution of lineage plasticity in prostate cancer, we applied single cell analyses to 21 human prostate tumor biopsies and two genetically engineered mouse models, together with tissue microarray analysis (TMA) on 131 tumor samples. Not only did we observe a higher degree of phenotypic heterogeneity in castrate-resistant PRAD and NEPC than previously anticipated, but also found that the expression of molecules targeted therapeutically, namely PSMA, STEAP1, STEAP2, TROP2, CEACAM5, and DLL3, varied within a subset of gene-regulatory networks (GRNs). We also noted that NEPC and small cell lung cancer (SCLC) subtypes shared a set of GRNs, indicative of conserved biologic pathways that may be exploited therapeutically across tumor types. While this extreme level of transcriptional heterogeneity, particularly in cell surface marker expression, may mitigate the durability of clinical responses to novel antigen-directed therapies, its delineation may yield signatures for patient selection in clinical trials, potentially across distinct cancer types.
RESUMO
The carboxyl terminus of Hsp70-interacting protein (CHIP) is a ubiquitin ligase/cochaperone critical for the maintenance of cardiac function. Mice lacking CHIP (CHIP-/-) suffer decreased survival, enhanced myocardial injury and increased arrhythmias compared with wild-type controls following challenge with cardiac ischaemia reperfusion injury. Recent evidence implicates a role for CHIP in chaperone-assisted selective autophagy, a process that is associated with exercise-induced cardioprotection. To determine whether CHIP is involved in cardiac autophagy, we challenged CHIP-/- mice with voluntary exercise. CHIP-/- mice respond to exercise with an enhanced autophagic response that is associated with an exaggerated cardiac hypertrophy phenotype. No impairment of function was identified in the CHIP-/- mice by serial echocardiography over the 5 weeks of running, indicating that the cardiac hypertrophy was physiologic not pathologic in nature. It was further determined that CHIP plays a role in inhibiting Akt signalling and autophagy determined by autophagic flux in cardiomyocytes and in the intact heart. Taken together, cardiac CHIP appears to play a role in regulating autophagy during the development of cardiac hypertrophy, possibly by its role in supporting Akt signalling, induced by voluntary running in vivo.
Assuntos
Autofagia , Cardiomegalia/metabolismo , Condicionamento Físico Animal , Ubiquitina-Proteína Ligases/química , Ubiquitina-Proteína Ligases/metabolismo , Animais , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Many studies have implicated the peroxisome proliferator-activated receptor (PPAR) family of nuclear receptor transcription factors in regulating cardiac substrate metabolism and ATP generation. Recently, evidence from a variety of cell culture and organ systems has implicated ubiquitin and small ubiquitin-like modifier (SUMO) conjugation as post-translational modifications that regulate the activity of PPAR transcription factors and their coreceptors/coactivators. Here we introduce the ubiquitin and SUMO conjugation systems and extensively review how they have been shown to regulate all three PPAR isoforms (PPARα, PPARß/δ, and PPARγ) in addition to the retinoid X receptor and PPARγ coactivator-1α subunits of the larger PPAR transcription factor complex. We then present how the specific ubiquitin (E3) ligases have been implicated and review emerging evidence that post-translational modifications of PPARs with ubiquitin and/or SUMO may play a role in cardiac disease. Because PPAR activity is perturbed in a variety of forms of heart disease and specific proteins regulate this process (E3 ligases), this may be a fruitful area of investigation with respect to finding new therapeutic targets.
Assuntos
Coração/fisiologia , Receptores Ativados por Proliferador de Peroxissomo/genética , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Sumoilação/fisiologia , Ubiquitinação/fisiologia , Animais , Metabolismo Energético/fisiologia , HumanosRESUMO
Drug resistance in cancer is often linked to changes in tumor cell state or lineage, but the molecular mechanisms driving this plasticity remain unclear. Using murine organoid and genetically engineered mouse models, we investigated the causes of lineage plasticity in prostate cancer and its relationship to antiandrogen resistance. We found that plasticity initiates in an epithelial population defined by mixed luminal-basal phenotype and that it depends on increased Janus kinase (JAK) and fibroblast growth factor receptor (FGFR) activity. Organoid cultures from patients with castration-resistant disease harboring mixed-lineage cells reproduce the dependency observed in mice by up-regulating luminal gene expression upon JAK and FGFR inhibitor treatment. Single-cell analysis confirms the presence of mixed-lineage cells with increased JAK/STAT (signal transducer and activator of transcription) and FGFR signaling in a subset of patients with metastatic disease, with implications for stratifying patients for clinical trials.
Assuntos
Plasticidade Celular , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB , Janus Quinases , Neoplasias da Próstata , Fatores de Transcrição STAT , Antagonistas de Androgênios , Animais , Humanos , Inibidores de Janus Quinases/uso terapêutico , Janus Quinases/genética , Janus Quinases/metabolismo , Masculino , Camundongos , Neoplasias Experimentais , Organoides , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Fatores de Transcrição STAT/genética , Fatores de Transcrição STAT/metabolismo , Transdução de SinaisRESUMO
INTRODUCTION: Previous studies have tested the hypothesis that calpain and/or proteasome inhibition is beneficial in Duchenne muscular dystrophy, based largely on evidence that calpain and proteasome activities are enhanced in the mdx mouse. METHODS: mRNA expression of ubiquitin-proteasome and calpain system components were determined using real-time polymerase chain reaction in skeletal muscle and heart in the golden retriever muscular dystrophy model. Similarly, calpain 1 and 2 and proteasome activities were determined using fluorometric activity assays. RESULTS: We found that less than half of the muscles tested had increases in proteasome activity, and only half had increased calpain activity. In addition, transcriptional regulation of the ubiquitin-proteasome system was most pronounced in the heart, where numerous components were significantly decreased. CONCLUSION: This study illustrates the diversity of expression and activities of the ubiquitin-proteasome and calpain systems, which may lead to unexpected consequences in response to pharmacological inhibition.
Assuntos
Calpaína/metabolismo , Músculo Esquelético/metabolismo , Distrofia Muscular Animal/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina/metabolismo , Animais , Calpaína/classificação , Calpaína/genética , Modelos Animais de Doenças , Cães , Regulação da Expressão Gênica/fisiologia , Distrofia Muscular Animal/metabolismo , Miocárdio/metabolismo , Complexo de Endopeptidases do Proteassoma/genética , Ubiquitina/genética , Complexos Ubiquitina-Proteína Ligase/metabolismoRESUMO
Forkhead box protein A1 (FOXA1) is essential for androgen-dependent prostate cancer (PCa) growth. However, how FOXA1 levels are regulated remains elusive and its therapeutic targeting proven challenging. Here, we report FOXA1 as a nonhistone substrate of enhancer of zeste homolog 2 (EZH2), which methylates FOXA1 at lysine-295. This methylation is recognized by WD40 repeat protein BUB3, which subsequently recruits ubiquitin-specific protease 7 (USP7) to remove ubiquitination and enhance FOXA1 protein stability. They functionally converge in regulating cell cycle genes and promoting PCa growth. FOXA1 is a major therapeutic target of the inhibitors of EZH2 methyltransferase activities in PCa. FOXA1-driven PCa growth can be effectively mitigated by EZH2 enzymatic inhibitors, either alone or in combination with USP7 inhibitors. Together, our study reports EZH2-catalyzed methylation as a key mechanism to FOXA1 protein stability, which may be leveraged to enhance therapeutic targeting of PCa using enzymatic EZH2 inhibitors.
RESUMO
Cancer heterogeneity impacts therapeutic response, driving efforts to discover over-arching rules that supersede variability. Here, we define pan-cancer binary classes based on distinct expression of YAP and YAP-responsive adhesion regulators. Combining informatics with in vivo and in vitro gain- and loss-of-function studies across multiple murine and human tumor types, we show that opposite pro- or anti-cancer YAP activity functionally defines binary YAPon or YAPoff cancer classes that express or silence YAP, respectively. YAPoff solid cancers are neural/neuroendocrine and frequently RB1-/-, such as retinoblastoma, small cell lung cancer, and neuroendocrine prostate cancer. YAP silencing is intrinsic to the cell of origin, or acquired with lineage switching and drug resistance. The binary cancer groups exhibit distinct YAP-dependent adhesive behavior and pharmaceutical vulnerabilities, underscoring clinical relevance. Mechanistically, distinct YAP/TEAD enhancers in YAPoff or YAPon cancers deploy anti-cancer integrin or pro-cancer proliferative programs, respectively. YAP is thus pivotal across cancer, but in opposite ways, with therapeutic implications.
Assuntos
Neoplasias Pulmonares/genética , Carcinoma de Pequenas Células do Pulmão/genética , Fatores de Transcrição de Domínio TEA/genética , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional/genética , Proteínas de Sinalização YAP/genética , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Elementos Facilitadores Genéticos , Regulação Neoplásica da Expressão Gênica , Humanos , Integrinas/metabolismo , Masculino , Camundongos Transgênicos , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Retina/genética , Neoplasias da Retina/patologia , Retinoblastoma/genética , Retinoblastoma/patologia , Proteínas de Ligação a Retinoblastoma/genética , Fatores de Transcrição de Domínio TEA/metabolismo , Ubiquitina-Proteína Ligases/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Chemoprevention trials for prostate cancer by androgen receptor or androgen synthesis inhibition have proven ineffective. Recently, it has been demonstrated that the histone methlytransferase, EZH2 is deregulated in mouse and human high-grade prostatic intraepithelial neoplasia (HG-PIN). Using preclinical mouse and human models of prostate cancer, we demonstrate that genetic and chemical disruption of EZH2 expression and catalytic activity reversed the HG-PIN phenotype. Furthermore, inhibition of EZH2 function was associated with loss of cellular proliferation and induction of Tp53-dependent senescence. Together, these data provide provocative evidence for EZH2 as an actionable therapeutic target toward prevention of prostate cancer.
Assuntos
Sistemas CRISPR-Cas , Proliferação de Células , Senescência Celular , Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Neoplasia Prostática Intraepitelial/prevenção & controle , Neoplasias da Próstata/prevenção & controle , Animais , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasia Prostática Intraepitelial/etiologia , Neoplasia Prostática Intraepitelial/metabolismo , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/etiologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologiaRESUMO
Methods based on homologous recombination to modify genes have significantly furthered biological research. Genetically engineered mouse models (GEMMs) are a rigorous method for studying mammalian development and disease. Our laboratory has developed several GEMMs of prostate cancer (PCa) that lack expression of one or multiple tumor suppressor genes using the site-specific Cre-loxP recombinase system and a prostate-specific promoter. In this article, we describe our method for necropsy of these PCa GEMMs, primarily focusing on dissection of mouse prostate tumors. New methods developed over the last decade have facilitated the culture of epithelial-derived cells to model organ systems in vitro in three dimensions. We also detail a 3D cell culture method to generate tumor organoids from mouse PCa GEMMs. Pre-clinical cancer research has been dominated by 2D cell culture and cell line-derived or patient-derived xenograft models. These methods lack tumor microenvironment, a limitation of using these techniques in pre-clinical studies. GEMMs are more physiologically-relevant for understanding tumorigenesis and cancer progression. Tumor organoid culture is an in vitro model system that recapitulates tumor architecture and cell lineage characteristics. In addition, 3D cell culture methods allow for growth of normal cells for comparison to tumor cell cultures, rarely possible using 2D cell culture techniques. In combination, use of GEMMs and 3D cell culture in pre-clinical studies has the potential to improve our understanding of cancer biology.
Assuntos
Técnicas de Cultura de Células/métodos , Organoides/patologia , Neoplasias da Próstata/genética , Animais , Modelos Animais de Doenças , Engenharia Genética , Masculino , Camundongos , Neoplasias da Próstata/patologia , Microambiente TumoralRESUMO
Therapeutic interventions for advanced prostate cancer (PCa) center on inhibiting androgen receptor (AR) and downstream signaling pathways. Resistance to androgen deprivation therapy and/or AR antagonists is inevitable and molecular mechanisms driving castration-resistant PCa (CR-PCa) primarily involve alterations in AR expression and activity. Detailed molecular biology work over the past decade, discussed at length in this review article, has revealed several AR transcripts that result from alternative splicing. These AR splice variants are increased in cell and mouse models of CR-PCa and in CR-PCa tumors. Several AR variants lack the ligand binding domain, but retain their ability to bind DNA and activate transcription-linking constitutive AR function and therapeutic failure. ARV7 is the only variant endogenously detected at the protein level and thus has undergone more thorough molecular characterization. Clinical trials in PCa are currently investigating ARV7 utility as a biomarker and new therapeutics that inhibit ARV7 . Overall, this review will illustrate the historical perspectives of AR splice variant discovery using fundamental molecular biology techniques and how it changed the clinical approach to both therapeutic decisions and strategy. The body of work investigating AR splice variants in PCa represents a true example of translational research from bench to bedside.
Assuntos
Neoplasias da Próstata/genética , Receptores Androgênicos/genética , Processamento Alternativo , Humanos , Masculino , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Isoformas de Proteínas , Receptores Androgênicos/metabolismoRESUMO
Prostate cancer variants expressing alternative lineage markers appear at relapse from antiandrogen therapy. We show that loss of the retinoblastoma (RB1) and tumor protein 53 (TP53) genes drives expression of stem cell reprogramming factors, lineage plasticity, and antiandrogen resistance. Epigenetic manipulation restores antiandrogen sensitivity-suggesting an approach for treating lethal prostate cancers.
RESUMO
Purpose: Current clinical parameters do not stratify indolent from aggressive prostate cancer. Aggressive prostate cancer, defined by the progression from localized disease to metastasis, is responsible for the majority of prostate cancer-associated mortality. Recent gene expression profiling has proven successful in predicting the outcome of prostate cancer patients; however, they have yet to provide targeted therapy approaches that could inhibit a patient's progression to metastatic disease.Experimental Design: We have interrogated a total of seven primary prostate cancer cohorts (n = 1,900), two metastatic castration-resistant prostate cancer datasets (n = 293), and one prospective cohort (n = 1,385) to assess the impact of TOP2A and EZH2 expression on prostate cancer cellular program and patient outcomes. We also performed IHC staining for TOP2A and EZH2 in a cohort of primary prostate cancer patients (n = 89) with known outcome. Finally, we explored the therapeutic potential of a combination therapy targeting both TOP2A and EZH2 using novel prostate cancer-derived murine cell lines.Results: We demonstrate by genome-wide analysis of independent primary and metastatic prostate cancer datasets that concurrent TOP2A and EZH2 mRNA and protein upregulation selected for a subgroup of primary and metastatic patients with more aggressive disease and notable overlap of genes involved in mitotic regulation. Importantly, TOP2A and EZH2 in prostate cancer cells act as key driving oncogenes, a fact highlighted by sensitivity to combination-targeted therapy.Conclusions: Overall, our data support further assessment of TOP2A and EZH2 as biomarkers for early identification of patients with increased metastatic potential that may benefit from adjuvant or neoadjuvant targeted therapy approaches. Clin Cancer Res; 23(22); 7072-83. ©2017 AACR.