RESUMEN
Kinase inhibitors have limited success in cancer treatment because tumors circumvent their action. Using a quantitative proteomics approach, we assessed kinome activity in response to MEK inhibition in triple-negative breast cancer (TNBC) cells and genetically engineered mice (GEMMs). MEK inhibition caused acute ERK activity loss, resulting in rapid c-Myc degradation that induced expression and activation of several receptor tyrosine kinases (RTKs). RNAi knockdown of ERK or c-Myc mimicked RTK induction by MEK inhibitors, and prevention of proteasomal c-Myc degradation blocked kinome reprogramming. MEK inhibitor-induced RTK stimulation overcame MEK2 inhibition, but not MEK1 inhibition, reactivating ERK and producing drug resistance. The C3Tag GEMM for TNBC similarly induced RTKs in response to MEK inhibition. The inhibitor-induced RTK profile suggested a kinase inhibitor combination therapy that produced GEMM tumor apoptosis and regression where single agents were ineffective. This approach defines mechanisms of drug resistance, allowing rational design of combination therapies for cancer.
Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Resistencia a Antineoplásicos , MAP Quinasa Quinasa 1/antagonistas & inhibidores , Proteínas Quinasas/genética , Proteoma/análisis , Animales , Antineoplásicos/uso terapéutico , Bencenosulfonatos/uso terapéutico , Bencimidazoles/uso terapéutico , Modelos Animales de Enfermedad , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones , Niacinamida/análogos & derivados , Compuestos de Fenilurea , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Piridinas/uso terapéutico , Proteínas Tirosina Quinasas Receptoras/genética , SorafenibRESUMEN
Androgen receptor splice variant 7 (AR-V7) is crucial for prostate cancer progression and therapeutic resistance. We show that, independent of ligand, AR-V7 binds both androgen-responsive elements (AREs) and non-canonical sites distinct from full-length AR (AR-FL) targets. Consequently, AR-V7 not only recapitulates AR-FL's partial functions but also regulates an additional gene expression program uniquely via binding to gene promoters rather than ARE enhancers. AR-V7 binding and AR-V7-mediated activation at these unique targets do not require FOXA1 but rely on ZFX and BRD4. Knockdown of ZFX or select unique targets of AR-V7/ZFX, or BRD4 inhibition, suppresses growth of castration-resistant prostate cancer cells. We also define an AR-V7 direct target gene signature that correlates with AR-V7 expression in primary tumors, differentiates metastatic prostate cancer from normal, and predicts poor prognosis. Thus, AR-V7 has both ARE/FOXA1 canonical and ZFX-directed non-canonical regulatory functions in the evolution of anti-androgen therapeutic resistance, providing information to guide effective therapeutic strategies.
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Empalme Alternativo/genética , Carcinogénesis/genética , Factores de Transcripción de Tipo Kruppel/genética , Oncogenes/genética , Neoplasias de la Próstata Resistentes a la Castración/genética , Receptores Androgénicos/genética , Animales , Diferenciación Celular/genética , Línea Celular , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica/genética , Células HEK293 , Factor Nuclear 3-alfa del Hepatocito/genética , Humanos , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Proteínas Nucleares/genética , Regiones Promotoras Genéticas/genéticaRESUMEN
Enhancer of Zeste Homolog 2 (EZH2) and androgen receptor (AR) are crucial chromatin/gene regulators involved in the development and/or progression of prostate cancer, including advanced castration-resistant prostate cancer (CRPC). To sustain prostate tumorigenicity, EZH2 establishes non-canonical biochemical interaction with AR for mediating oncogene activation, in addition to its canonical role as a transcriptional repressor and enzymatic subunit of Polycomb Repressive Complex 2 (PRC2). However, the molecular basis underlying non-canonical activities of EZH2 in prostate cancer remains elusive, and a therapeutic strategy for targeting EZH2:AR-mediated oncogene activation is also lacking. Here, we report that a cryptic transactivation domain of EZH2 (EZH2TAD) binds both AR and AR spliced variant 7 (AR-V7), a constitutively active AR variant enriched in CRPC, mediating assembly and/or recruitment of transactivation-related machineries at genomic sites that lack PRC2 binding. Such non-canonical targets of EZH2:AR/AR-V7:(co-)activators are enriched for the clinically relevant oncogenes. We also show that EZH2TAD is required for the chromatin recruitment of EZH2 to oncogenes, for EZH2-mediated oncogene activation and for CRPC growth in vitro and in vivo. To completely block EZH2's multifaceted oncogenic activities in prostate cancer, we employed MS177, a recently developed proteolysis-targeting chimera (PROTAC) of EZH2. Strikingly, MS177 achieved on-target depletion of both EZH2's canonical (EZH2:PRC2) and non-canonical (EZH2TAD:AR/AR-V7:co-activators) complexes in prostate cancer cells, eliciting far more potent antitumor effects than the catalytic inhibitors of EZH2. Overall, this study reports a previously unappreciated requirement for EZH2TAD for mediating EZH2's non-canonical (co-)activator recruitment and gene activation functions in prostate cancer and suggests EZH2-targeting PROTACs as a potentially attractive therapeutic for the treatment of aggressive prostate cancer that rely on the circuits wired by EZH2 and AR.
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Proteína Potenciadora del Homólogo Zeste 2 , Neoplasias de la Próstata Resistentes a la Castración , Receptores Androgénicos , Humanos , Masculino , Línea Celular Tumoral , Cromatina/genética , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Regulación Neoplásica de la Expresión Génica , Oncogenes , Complejo Represivo Polycomb 2/genética , Complejo Represivo Polycomb 2/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/patología , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Activación Transcripcional , Isoformas de ProteínasRESUMEN
In this issue honoring the contributions of Greg Lemke, the Earp and Graham lab teams discuss several threads in the discovery, action, signaling, and translational/clinical potential of MERTK, originally called c-mer, a member of the TYRO3, AXL, and MERTK (TAM) family of receptor tyrosine kinases. The 30-year history of the TAM RTK family began slowly as all three members were orphan RTKs without known ligands and/or functions when discovered by three distinct alternate molecular cloning strategies in the pre-genome sequencing era. The pace of understanding their physiologic and pathophysiologic roles has accelerated over the last decade. The activation of ligands bridging externalized phosphatidylserine (PtdSer) has placed these RTKs in a myriad of processes including neurodevelopment, cancer, and autoimmunity. The field is ripe for further advancement and this article hopefully sets the stage for further understanding and therapeutic intervention. Our review will focus on progress made through the collaborations of the Earp and Graham labs over the past 30 years.
Asunto(s)
Neoplasias , Tirosina Quinasa c-Mer , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Tirosina Quinasa c-Mer/metabolismo , Tirosina Quinasa c-Mer/antagonistas & inhibidores , Tirosina Quinasa c-Mer/genética , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Animales , Terapia Molecular Dirigida , Transducción de Señal/efectos de los fármacos , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Proteínas Tirosina Quinasas Receptoras/metabolismo , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidoresRESUMEN
Castration-resistant prostate cancer (CRPC) is a terminal disease and the molecular underpinnings of CRPC development need to be better understood in order to improve its treatment. Here, we report that a transcription factor Yin Yang 1 (YY1) is significantly overexpressed during prostate cancer progression. Functional and cistrome studies of YY1 uncover its roles in promoting prostate oncogenesis in vitro and in vivo, as well as sustaining tumor metabolism including the Warburg effect and mitochondria respiration. Additionally, our integrated genomics and interactome profiling in prostate tumor show that YY1 and bromodomain-containing proteins (BRD2/4) co-occupy a majority of gene-regulatory elements, coactivating downstream targets. Via gene loss-of-function and rescue studies and mutagenesis of YY1-bound cis-elements, we unveil an oncogenic pathway in which YY1 directly binds and activates PFKP, a gene encoding the rate-limiting enzyme for glycolysis, significantly contributing to the YY1-enforced Warburg effect and malignant growth. Altogether, this study supports a master regulator role for YY1 in prostate tumorigenesis and reveals a YY1:BRD2/4-PFKP axis operating in advanced prostate cancer with implications for therapy.
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Regulación Neoplásica de la Expresión Génica , Fosfofructoquinasa-1 Tipo C/genética , Neoplasias de la Próstata Resistentes a la Castración/genética , Factor de Transcripción YY1/metabolismo , Animales , Carcinogénesis , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Glucólisis , Células HEK293 , Humanos , Masculino , Ratones SCID , Fosfofructoquinasa-1 Tipo C/fisiología , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/patología , Factores de Transcripción/metabolismo , Activación Transcripcional , Factor de Transcripción YY1/genética , Factor de Transcripción YY1/fisiologíaRESUMEN
Non-Hodgkin lymphomas (NHLs) make up the majority of lymphoma diagnoses and represent a very diverse set of malignancies. We sought to identify kinases uniquely up-regulated in different NHL subtypes. Using multiplexed inhibitor bead-mass spectrometry (MIB/MS), we found Tyro3 was uniquely up-regulated and important for cell survival in primary effusion lymphoma (PEL), which is a viral lymphoma infected with Kaposi's sarcoma-associated herpesvirus (KSHV). Tyro3 was also highly expressed in PEL cell lines as well as in primary PEL exudates. Based on this discovery, we developed an inhibitor against Tyro3 named UNC3810A, which hindered cell growth in PEL, but not in other NHL subtypes where Tyro3 was not highly expressed. UNC3810A also significantly inhibited tumor progression in a PEL xenograft mouse model that was not seen in a non-PEL NHL model. Taken together, our data suggest Tyro3 is a therapeutic target for PEL.
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Linfoma no Hodgkin/enzimología , Linfoma de Efusión Primaria/enzimología , Terapia Molecular Dirigida , Proteoma/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Animales , Apoptosis/efectos de los fármacos , Linfocitos B/efectos de los fármacos , Linfocitos B/virología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Femenino , Ratones , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacosRESUMEN
PURPOSE: Female breast cancer demonstrates bimodal age frequency distribution patterns at diagnosis, interpretable as two main etiologic subtypes or groupings of tumors with shared risk factors. While RNA-based methods including PAM50 have identified well-established clinical subtypes, age distribution patterns at diagnosis as a proxy for etiologic subtype are not established for molecular and genomic tumor classifications. METHODS: We evaluated smoothed age frequency distributions at diagnosis for Carolina Breast Cancer Study cases within immunohistochemistry-based and RNA-based expression categories. Akaike information criterion (AIC) values compared the fit of single density versus two-component mixture models. Two-component mixture models estimated the proportion of early-onset and late-onset categories by immunohistochemistry-based ER (n = 2860), and by RNA-based ESR1 and PAM50 subtype (n = 1965). PAM50 findings were validated using pooled publicly available data (n = 8103). RESULTS: Breast cancers were best characterized by bimodal age distribution at diagnosis with incidence peaks near 45 and 65 years, regardless of molecular characteristics. However, proportional composition of early-onset and late-onset age distributions varied by molecular and genomic characteristics. Higher ER-protein and ESR1-RNA categories showed a greater proportion of late age-at-onset. Similarly, PAM50 subtypes showed a shifting age-at-onset distribution, with most pronounced early-onset and late-onset peaks found in Basal-like and Luminal A, respectively. CONCLUSIONS: Bimodal age distribution at diagnosis was detected in the Carolina Breast Cancer Study, similar to national cancer registry data. Our data support two fundamental age-defined etiologic breast cancer subtypes that persist across molecular and genomic characteristics. Better criteria to distinguish etiologic subtypes could improve understanding of breast cancer etiology and contribute to prevention efforts.
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Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/diagnóstico , Genómica/métodos , Distribución por Edad , Edad de Inicio , Anciano , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Análisis de Secuencia de ARNRESUMEN
PURPOSE: Understanding breast cancer mortality disparities by race and age is complex due to disease heterogeneity, comorbid disease, and the range of factors influencing access to care. It is important to understand how these factors group together within patients. METHODS: We compared socioeconomic status (SES) and comorbidity factors in the Carolina Breast Cancer Study Phase 3 (CBCS3, 2008-2013) to those for North Carolina using the 2010 Behavioral Risk Factor Surveillance Study. In addition, we used latent class analysis of CBCS3 data to identify covariate patterns by SES/comorbidities, barriers to care, and tumor characteristics and examined their associations with race and age using multinomial logistic regression. RESULTS: Major SES and comorbidity patterns in CBCS3 participants were generally similar to patterns in the state. Latent classes were identified for SES/comorbidities, barriers to care, and tumor characteristics that varied by race and age. Compared to white women, black women had lower SES (odds ratio (OR) 6.3, 95% confidence interval (CI) 5.2, 7.8), more barriers to care (OR 5.6, 95% CI 3.9, 8.1) and several aggregated tumor aggressiveness features. Compared to older women, younger women had higher SES (OR 0.5, 95% CI 0.4, 0.6), more barriers to care (OR 2.1, 95% CI 1.6, 2.9) and aggregated tumor aggressiveness features. CONCLUSIONS: CBCS3 is representative of North Carolina on comparable factors. Patterns of access to care and tumor characteristics are intertwined with race and age, suggesting that interventions to address disparities will need to target both access and biology.
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Neoplasias de la Mama/etnología , Neoplasias de la Mama/mortalidad , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Adulto , Negro o Afroamericano/estadística & datos numéricos , Anciano , Comorbilidad , Femenino , Humanos , Modelos Logísticos , Persona de Mediana Edad , North Carolina/epidemiología , Oportunidad Relativa , Clase Social , Factores SocioeconómicosRESUMEN
Controlling which particular members of a large protein family are targeted by a drug is key to achieving a desired therapeutic response. In this study, we report a rational data-driven strategy for achieving restricted polypharmacology in the design of antitumor agents selectively targeting the TYRO3, AXL, and MERTK (TAM) family tyrosine kinases. Our computational approach, based on the concept of fragments in structural environments (FRASE), distills relevant chemical information from structural and chemogenomic databases to assemble a three-dimensional inhibitor structure directly in the protein pocket. Target engagement by the inhibitors designed led to disruption of oncogenic phenotypes as demonstrated in enzymatic assays and in a panel of cancer cell lines, including acute lymphoblastic and myeloid leukemia (ALL/AML) and nonsmall cell lung cancer (NSCLC). Structural rationale underlying the approach was corroborated by X-ray crystallography. The lead compound demonstrated potent target inhibition in a pharmacodynamic study in leukemic mice.
Asunto(s)
Antineoplásicos/química , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Secuencia de Aminoácidos , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ratones , Estructura Molecular , Neoplasias ExperimentalesRESUMEN
BACKGROUND: Using next-generation sequencing (NGS) to guide cancer therapy has created challenges in analyzing and reporting large volumes of genomic data to patients and caregivers. Specifically, providing current, accurate information on newly approved therapies and open clinical trials requires considerable manual curation performed mainly by human "molecular tumor boards" (MTBs). The purpose of this study was to determine the utility of cognitive computing as performed by Watson for Genomics (WfG) compared with a human MTB. MATERIALS AND METHODS: One thousand eighteen patient cases that previously underwent targeted exon sequencing at the University of North Carolina (UNC) and subsequent analysis by the UNCseq informatics pipeline and the UNC MTB between November 7, 2011, and May 12, 2015, were analyzed with WfG, a cognitive computing technology for genomic analysis. RESULTS: Using a WfG-curated actionable gene list, we identified additional genomic events of potential significance (not discovered by traditional MTB curation) in 323 (32%) patients. The majority of these additional genomic events were considered actionable based upon their ability to qualify patients for biomarker-selected clinical trials. Indeed, the opening of a relevant clinical trial within 1 month prior to WfG analysis provided the rationale for identification of a new actionable event in nearly a quarter of the 323 patients. This automated analysis took <3 minutes per case. CONCLUSION: These results demonstrate that the interpretation and actionability of somatic NGS results are evolving too rapidly to rely solely on human curation. Molecular tumor boards empowered by cognitive computing could potentially improve patient care by providing a rapid, comprehensive approach for data analysis and consideration of up-to-date availability of clinical trials. IMPLICATIONS FOR PRACTICE: The results of this study demonstrate that the interpretation and actionability of somatic next-generation sequencing results are evolving too rapidly to rely solely on human curation. Molecular tumor boards empowered by cognitive computing can significantly improve patient care by providing a fast, cost-effective, and comprehensive approach for data analysis in the delivery of precision medicine. Patients and physicians who are considering enrollment in clinical trials may benefit from the support of such tools applied to genomic data.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias/tratamiento farmacológico , Biomarcadores de Tumor , Estudios de Casos y Controles , Terapia Combinada , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Metástasis Linfática , Invasividad Neoplásica , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Neoplasias/patología , Pronóstico , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
Acute lymphoblastic leukemia (ALL) is currently treated with an intense regimen of chemotherapy yielding cure rates near 85%. However, alterations to treatment strategies using available drugs are unlikely to provide significant improvement in survival or decrease therapy-associated toxicities. Here, we report ectopic expression of the Mer receptor tyrosine kinase in pre-B-cell ALL (B-ALL) cell lines and pediatric patient samples. Inhibition of Mer in B-ALL cell lines decreased activation of AKT and MAPKs and led to transcriptional changes, including decreased expression of antiapoptotic PRKCB gene and increase in proapoptotic BAX and BBC3 genes. Further, Mer inhibition promoted chemosensitization, decreased colony-forming potential in clonogenic assays, and delayed disease onset in a mouse xenograft model of leukemia. Our results identify Mer as a potential therapeutic target in B-ALL and suggest that inhibitors of Mer may potentiate lymphoblast killing when used in combination with chemotherapy. This strategy could reduce minimal residual disease and/or allow for chemotherapy dose reduction, thereby leading to improved event-free survival and reduced therapy-associated toxicity for patients with B-ALL. Additionally, Mer is aberrantly expressed in numerous other malignancies suggesting that this approach may have broad applications.
Asunto(s)
Terapia Molecular Dirigida , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamiento farmacológico , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Animales , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , ARN Interferente Pequeño/farmacología , ARN Interferente Pequeño/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto , Tirosina Quinasa c-MerRESUMEN
Ewing sarcoma is a pediatric bone and soft tissue tumor treated with chemotherapy, radiation, and surgery. Despite intensive multimodality therapy, ~50% patients eventually relapse and die of the disease due to chemoresistance. Here, using phospho-profiling, we find Ewing sarcoma cells treated with chemotherapeutic agents activate TAM (TYRO3, AXL, MERTK) kinases to augment Akt and ERK signaling facilitating chemoresistance. Mechanistically, chemotherapy-induced JAK1-SQ phosphorylation releases JAK1 pseudokinase domain inhibition allowing for JAK1 activation. This alternative JAK1 activation mechanism leads to STAT6 nuclear translocation triggering transcription and secretion of the TAM kinase ligand GAS6 with autocrine/paracrine consequences. Importantly, pharmacological inhibition of either JAK1 by filgotinib or TAM kinases by UNC2025 sensitizes Ewing sarcoma to chemotherapy in vitro and in vivo. Excitingly, the TAM kinase inhibitor MRX-2843 currently in human clinical trials to treat AML and advanced solid tumors, enhances chemotherapy efficacy to further suppress Ewing sarcoma tumor growth in vivo. Our findings reveal an Ewing sarcoma chemoresistance mechanism with an immediate translational value.
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Péptidos y Proteínas de Señalización Intercelular , Janus Quinasa 1 , Proteínas Tirosina Quinasas Receptoras , Sarcoma de Ewing , Transducción de Señal , Sarcoma de Ewing/tratamiento farmacológico , Sarcoma de Ewing/metabolismo , Sarcoma de Ewing/patología , Sarcoma de Ewing/genética , Humanos , Janus Quinasa 1/metabolismo , Janus Quinasa 1/antagonistas & inhibidores , Janus Quinasa 1/genética , Línea Celular Tumoral , Animales , Transducción de Señal/efectos de los fármacos , Proteínas Tirosina Quinasas Receptoras/metabolismo , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Ratones , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Tirosina Quinasa del Receptor Axl , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Neoplasias Óseas/genética , Ensayos Antitumor por Modelo de Xenoinjerto , Tirosina Quinasa c-Mer/metabolismo , Tirosina Quinasa c-Mer/genética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Fosforilación/efectos de los fármacos , Femenino , Factor de Transcripción STAT6RESUMEN
Checkpoint inhibitors, specifically anti-PD-1, have shown success in treating metastatic melanoma; however, some patients develop resistance. Dendritic cells (DCs) play a key role in initiating an immune response but in certain circumstances they become ineffective. We investigated the role of MerTK, a receptor tyrosine kinase responsible for myeloid cell clearance of dead cells, in the regulation of DC function and metabolism in the tumor microenvironment. Tumors resistant to anti-PD-1 exhibited increased levels of MerTK+ DCs. Treating wild-type DCs with apoptotic dead melanoma cells in vitro resulted in increased MerTK expression, elevated mitochondrial respiration and fatty acid oxidation, and reduced T-cell stimulatory capacity, all characteristics of dysfunctional DCs. In contrast, dead cells had only limited effect on the metabolism of MerTK-deficient DCs, which instead maintained an antigen presenting, stimulatory phenotype. The efficacy of anti-PD-1 to slow tumor progression and induce specific T-cell infiltration was markedly increased in mice with selective ablation of MerTK in the DC compartment, suggesting the possibility of therapeutically targeting MerTK to modulate DC metabolism and function and enhance anti-PD-1 therapy.
RESUMEN
MERTK and AXL are members of the TAM (TYRO3, AXL, MERTK) family of receptor tyrosine kinases that are aberrantly expressed and have been implicated as therapeutic targets in a wide variety of human tumors. Dual MERTK and AXL inhibition could provide antitumor action mediated by both direct tumor cell killing and modulation of the innate immune response in some tumors such as nonsmall cell lung cancer. We utilized our knowledge of MERTK inhibitors and a structure-based drug design approach to discover a novel class of macrocyclic dual MERTK/AXL inhibitors. The lead compound 43 had low-nanomolar activity against both MERTK and AXL and good selectivity over TYRO3 and FLT3. Its target engagement and selectivity were also confirmed by NanoBRET and cell-based MERTK and AXL phosphorylation assays. Compound 43 had excellent pharmacokinetic properties (large AUC and long half-life) and mediated antitumor activity against lung cancer cell lines, indicating its potential as a therapeutic agent.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Tirosina Quinasa c-Mer/metabolismo , Tirosina Quinasa del Receptor Axl , Proteínas Proto-Oncogénicas/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Línea Celular TumoralRESUMEN
PURPOSE: Genomic tests, such as the Oncotype Dx 21-gene and Prosigna risk of recurrence (ROR-P) assay, are commonly used for breast cancer prognostication. Emerging data suggest variability between assays, but this has not been compared in diverse populations. MATERIALS AND METHODS: RNA sequencing was performed on 647 previously untreated stage I-III estrogen receptor-positive/human epidermal growth factor receptor 2-negative tumors in the Carolina Breast Cancer Study, which oversampled Black and younger women (age <50 years at diagnosis), using research versions of two common RNA-based prognostic assays: ROR-PR and the 21-gene recurrence score (RSR). Relative frequency differences and 95% CIs were estimated for associations with race and age, and hazards of 5-year local or distant recurrence were modeled with Cox regression. Proliferation and estrogen module scores from each assay, representing broad activity of genes in those pathways, were examined to guide interpretation of differences between tests. RESULTS: Among both younger and older individuals, Black women had higher frequency of intermediate and high ROR-PR scores than non-Black women. Race was not significantly associated with RSR in either age group. High (hazard ratio [HR], 4.67 [95% CI, 1.73 to 12.70]) and intermediate (HR, 2.12 [95% CI, 0.98 to 4.62]) ROR-PR scores were associated with greater risk of recurrence, but RSR did not predict recurrence. RSR emphasized estrogen over proliferation modules, whereas ROR-PR emphasized proliferation. Higher proliferation scores were associated with younger age and Black race in both assays. Modifications to the RSR algorithm that increased emphasis on proliferation improved prognostication in this diverse population. CONCLUSION: ROR-PR and the 21-gene RSR differentially emphasize estrogen-related and proliferative biology. The emphasis of 21-gene RS on estrogen-related biology and lower endocrine therapy initiation among Black women may contribute to poorer prognostic ability in heterogeneously treated populations.
Asunto(s)
Neoplasias de la Mama , Recurrencia Local de Neoplasia , Humanos , Femenino , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Persona de Mediana Edad , Adulto , Recurrencia Local de Neoplasia/genética , Negro o Afroamericano/genética , Factores de Edad , Anciano , PronósticoRESUMEN
Novel treatment approaches are needed to overcome innate and acquired mechanisms of resistance to current anticancer therapies in cancer cells and the tumour immune microenvironment. The TAM (TYRO3, AXL and MERTK) family receptor tyrosine kinases (RTKs) are potential therapeutic targets in a wide range of cancers. In cancer cells, TAM RTKs activate signalling pathways that promote cell survival, metastasis and resistance to a variety of chemotherapeutic agents and targeted therapies. TAM RTKs also function in innate immune cells, contributing to various mechanisms that suppress antitumour immunity and promote resistance to immune-checkpoint inhibitors. Therefore, TAM antagonists provide an unprecedented opportunity for both direct and immune-mediated therapeutic activity provided by inhibition of a single target, and are likely to be particularly effective when used in combination with other cancer therapies. To exploit this potential, a variety of agents have been designed to selectively target TAM RTKs, many of which have now entered clinical testing. This Review provides an essential guide to the TAM RTKs for clinicians, including an overview of the rationale for therapeutic targeting of TAM RTKs in cancer cells and the tumour immune microenvironment, a description of the current preclinical and clinical experience with TAM inhibitors, and a perspective on strategies for continued development of TAM-targeted agents for oncology applications.
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Tirosina Quinasa del Receptor Axl , Neoplasias , Humanos , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Neoplasias/tratamiento farmacológico , Tirosina Quinasa c-Mer/genética , Tirosina Quinasa c-Mer/metabolismo , Microambiente TumoralRESUMEN
The chemokine receptor CCR2 plays a key role in cellular migration and inflammatory processes. While tremendous progress has been made in elucidating CCR2 function and inhibition, the majority of approaches target its N-terminal domain and less is known about the function of the remaining extracellular loops and their potential as targets. Here, we used phage display to identify an antibody-derived scFv (single chain variable fragment) clone that specifically targets the second extracellular epitope of CCR2 (ECL2) for inhibition. Using in silico molecular docking, we identified six potential primary binding conformations of the novel scFv to the specified CCR2 epitope. In silico molecular dynamic analysis was used to determine conformational stability and identify protein-protein interactions. Umbrella sampling of a range of configurations with incrementally increasing separation of scFv and target generated by force pulling simulations was used to calculate binding energies. Downstream characterization by ELISA showed high binding affinity of the ECL2-scFv to CCR2. Furthermore, we showed that blocking the second extracellular loop inhibits macrophage migration and polarized macrophages towards M1 inflammatory cytokine production as potently as lipopolysaccharide (LPS). These studies highlight the applicability of epitope-specific targeting, emphasize the importance of in silico predictive modeling, and warrant further investigation into the role of the remaining epitopes of CCR2.
Asunto(s)
Anticuerpos de Cadena Única , Simulación del Acoplamiento Molecular , Anticuerpos de Cadena Única/química , Epítopos , Simulación de Dinámica Molecular , Conformación MolecularRESUMEN
The challenge of rapid macromolecular synthesis enforces the energy-hungry cancer cell mitochondria to switch their metabolic phenotypes, accomplished by activation of oncogenic tyrosine kinases. Precisely how kinase activity is directly exploited by cancer cell mitochondria to meet high-energy demand, remains to be deciphered. Here we show that a non-receptor tyrosine kinase, TNK2/ACK1 (tyrosine kinase non receptor 2), phosphorylated ATP5F1A (ATP synthase F1 subunit alpha) at Tyr243 and Tyr246 (Tyr200 and 203 in the mature protein, respectively) that not only increased the stability of complex V, but also increased mitochondrial energy output in cancer cells. Further, phospho-ATP5F1A (p-Y-ATP5F1A) prevented its binding to its physiological inhibitor, ATP5IF1 (ATP synthase inhibitory factor subunit 1), causing sustained mitochondrial activity to promote cancer cell growth. TNK2 inhibitor, (R)-9b reversed this process and induced mitophagy-based autophagy to mitigate prostate tumor growth while sparing normal prostate cells. Further, depletion of p-Y-ATP5F1A was needed for (R)-9b-mediated mitophagic response and tumor growth. Moreover, Tnk2 transgenic mice displayed increased p-Y-ATP5F1A and loss of mitophagy and exhibited formation of prostatic intraepithelial neoplasia (PINs). Consistent with these data, a marked increase in p-Y-ATP5F1A was seen as prostate cancer progressed to the malignant stage. Overall, this study uncovered the molecular intricacy of tyrosine kinase-mediated mitochondrial energy regulation as a distinct cancer cell mitochondrial vulnerability and provided evidence that TNK2 inhibitors can act as "mitocans" to induce cancer-specific mitophagy.Abbreviations: ATP5F1A: ATP synthase F1 subunit alpha; ATP5IF1: ATP synthase inhibitory factor subunit 1; CRPC: castration-resistant prostate cancer; DNM1L: dynamin 1 like; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; Mdivi-1: mitochondrial division inhibitor 1; Mut-ATP5F1A: Y243,246A mutant of ATP5F1A; OXPHOS: oxidative phosphorylation; PC: prostate cancer; PINK1: PTEN induced kinase 1; p-Y-ATP5F1A: phosphorylated tyrosine 243 and 246 on ATP5F1A; TNK2/ACK1: tyrosine kinase non receptor 2; Ub: ubiquitin; WT: wild type.
Asunto(s)
Autofagia , Neoplasias de la Próstata , Humanos , Masculino , Ratones , Animales , Fosforilación , Proteínas Tirosina Quinasas/metabolismo , Ratones Transgénicos , Mitocondrias/metabolismo , Tirosina , Adenosina Trifosfato/metabolismoRESUMEN
Background: Previous studies show that the spleen and bone marrow can serve as leukemia microenvironments in which macrophages play a significant role in immune evasion and chemoresistance. We hypothesized that the macrophage driven tolerogenic process of efferocytosis is a major contributor to the immunosuppressive leukemia microenvironment and that this was driven by aberrant phosphatidylserine expression from cell turnover and cell membrane dysregulation. Methods: Since MerTK is the prototypic efferocytosis receptor, we assessed whether the MerTK inhibitor MRX2843, which is currently in clinical trials, would reverse immune evasion and enhance immune-mediated clearance of leukemia cells. Results: We found that inhibition of MerTK decreased leukemia-associated macrophage expression of M2 markers PD-L1, PD-L2, Tim-3, CD163 and Arginase-1 compared to vehicle-treated controls. Additionally, MerTK inhibition led to M1 macrophage repolarization including elevated CD86 and HLA-DR expression, and increased production of T cell activating cytokines, including IFN-ß, IL-18, and IL-1ß through activation of NF-κB. Collectively, this macrophage repolarization had downstream effects on T cells within the leukemia microenvironment, including decreased PD-1+Tim-3+ and LAG3+ checkpoint expression, and increased CD69+CD107a+ expression. Discussion: These results demonstrate that MerTK inhibition using MRX2843 altered the leukemia microenvironment from tumor-permissive toward immune responsiveness to leukemia and culminated in improved immune-mediated clearance of AML.
Asunto(s)
Receptor 2 Celular del Virus de la Hepatitis A , Leucemia , Humanos , Tirosina Quinasa c-Mer/metabolismo , Receptor 2 Celular del Virus de la Hepatitis A/metabolismo , Macrófagos , Leucemia/metabolismo , Terapia de Inmunosupresión , Microambiente TumoralRESUMEN
The peritoneal cavity is recognized as an important site for autoreactive B cells prior to their transit to other immune tissues; however, little is known of the genes that may regulate this process. Mice lacking the receptor tyrosine kinase, Mertk, display a lupus-like autoimmune phenotype with splenomegaly and high autoantibodies titers. In this study, we investigate whether Mertk regulates the composition of peritoneal cells that favor an autoimmune phenotype. We found an increase in the number of macrophages, dendritic cells (DCs), plasmacytoid DCs, T cells, and B cells in the peritoneal cavity of mertk-/- mice when compared with wild-type mice. This disparity in cell numbers was not due to changes in cell proliferation or cell death. In adoptive transfer experiments, we showed an increase in migration of labeled donor cells into the mertk-/- peritoneal cavity. In addition, bone marrow chimeric mice showed hematopoietic-derived factors were also critical for T cell migration. Consistent with this migration and the increase in the number of cells, we identified elevated expression of CXCL9, its receptor CXCR3, and IL-7R on peritoneal cells from mertk-/- mice. To corroborate the migratory function of CXCR3 on cells, the depletion of CXCR3 donor cells significantly reduced the number of adoptively transferred cells that entered into the peritoneum of mertk-/- mice. This control of peritoneal cells numbers correlated with autoantibody production and was exclusively attributed to Mertk because mice lacking other family members, Axl or Tyro 3, did not display dysregulation in peritoneal cell numbers or the autoimmune phenotype.