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We used clinical tissue from lethal metastatic castration-resistant prostate cancer (CRPC) patients obtained at rapid autopsy to evaluate diverse genomic, transcriptomic, and phosphoproteomic datasets for pathway analysis. Using Tied Diffusion through Interacting Events (TieDIE), we integrated differentially expressed master transcriptional regulators, functionally mutated genes, and differentially activated kinases in CRPC tissues to synthesize a robust signaling network consisting of druggable kinase pathways. Using MSigDB hallmark gene sets, six major signaling pathways with phosphorylation of several key residues were significantly enriched in CRPC tumors after incorporation of phosphoproteomic data. Individual autopsy profiles developed using these hallmarks revealed clinically relevant pathway information potentially suitable for patient stratification and targeted therapies in late stage prostate cancer. Here, we describe phosphorylation-based cancer hallmarks using integrated personalized signatures (pCHIPS) that shed light on the diversity of activated signaling pathways in metastatic CRPC while providing an integrative, pathway-based reference for drug prioritization in individual patients.
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Fosfoproteínas/análise , Neoplasias de Próstata Resistentes à Castração/química , Proteoma/análise , Algoritmos , Humanos , Masculino , Medicina de Precisão , Neoplasias de Próstata Resistentes à Castração/metabolismo , Transdução de Sinais , TranscriptomaRESUMO
The accurate assessment of hemodynamics is paramount to providing timely and efficacious care for patients presenting in cardiogenic shock. Recently, the regular use of the pulmonary artery catheter in cardiogenic shock has had a resurgence with emerging data indicating improved survival in the modern era. Optimal multidisciplinary management of advanced heart failure and cardiogenic shock relies on our ability to effectively communicate and understand the complete hemodynamic assessment. Standardization of data acquisition and a renewed focus on the physiological processes, and thresholds driving disease progression, including the coupling ratio and myocardial reserve, are needed to fully understand and interpret the hemodynamic assessment. This State-of-the-Art review discusses best practices in the cardiac catheterization laboratory as well as emerging data on the prognostic role of emerging advanced hemodynamic parameters.
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Insuficiência Cardíaca , Humanos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Choque Cardiogênico , Hemodinâmica/fisiologia , Cateterismo Cardíaco , Padrões de ReferênciaRESUMO
Small cell carcinoma of the bladder (SCCB) is a rare and lethal phenotype of bladder cancer. The pathogenesis and molecular features are unknown. Here, we established a genetically engineered SCCB model and a cohort of patient SCCB and urothelial carcinoma samples to characterize molecular similarities and differences between bladder cancer phenotypes. We demonstrate that SCCB shares a urothelial origin with other bladder cancer phenotypes by showing that urothelial cells driven by a set of defined oncogenic factors give rise to a mixture of tumor phenotypes, including small cell carcinoma, urothelial carcinoma, and squamous cell carcinoma. Tumor-derived single-cell clones also give rise to both SCCB and urothelial carcinoma in xenografts. Despite this shared urothelial origin, clinical SCCB samples have a distinct transcriptional profile and a unique transcriptional regulatory network. Using the transcriptional profile from our cohort, we identified cell surface proteins (CSPs) associated with the SCCB phenotype. We found that the majority of SCCB samples have PD-L1 expression in both tumor cells and tumor-infiltrating lymphocytes, suggesting that immune checkpoint inhibitors could be a treatment option for SCCB. We further demonstrate that our genetically engineered tumor model is a representative tool for investigating CSPs in SCCB by showing that it shares a similar a CSP profile with clinical samples and expresses SCCB-up-regulated CSPs at both the mRNA and protein levels. Our findings reveal distinct molecular features of SCCB and provide a transcriptional dataset and a preclinical model for further investigating SCCB biology.
Assuntos
Carcinoma de Células Pequenas/patologia , Carcinoma de Células de Transição/patologia , Transformação Celular Neoplásica/genética , Neoplasias da Bexiga Urinária/patologia , Bexiga Urinária/patologia , Urotélio/patologia , Animais , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/metabolismo , Carcinoma de Células Pequenas/genética , Carcinoma de Células Pequenas/terapia , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/terapia , Transformação Celular Neoplásica/efeitos dos fármacos , Células Cultivadas , Cistectomia , Conjuntos de Dados como Assunto , Células Epiteliais , Regulação Neoplásica da Expressão Gênica , Engenharia Genética , Humanos , Linfócitos do Interstício Tumoral/metabolismo , Camundongos , Cultura Primária de Células , RNA-Seq , Bexiga Urinária/citologia , Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/terapia , Urotélio/citologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
PURPOSE: Tolvaptan, a selective vasopressin type-2 antagonist, has been shown to increase serum sodium (Na) and urine output in hyponatremic left ventricular assist device (LVAD) patients in retrospective studies. In this prospective randomized pilot study, we aimed to assess the efficacy of tolvaptan in this population. METHODS: We conducted a prospective, randomized, non-blinded pilot study of LVAD recipients with post-operative hyponatremia (Na < 135 mEq/L) (NCT05408104). Eligible participants were randomized to receive tolvaptan 15 mg daily in addition to usual care versus usual care alone. The primary outcome was a change in Na level and estimated glomerular filtration rate (eGFR), from the first post-operative day of hyponatremia (the day of randomization) to discharge. RESULTS: A total of 33 participants were enrolled, and 28 underwent randomization (median age 55 [IQR 50-62]), 21% women, 54% Black, 32% ischemic cardiomyopathy, median baseline Na 135 (IQR 134-138). Fifteen participants were randomized to tolvaptan (TLV) and 13 were randomized to usual care alone (No-TLV). Mean change in Na from randomization to discharge in the TLV group was 2.7 mEq/L (95%CI 0.7-4.7, p = 0.013) and 1.8 (95%CI 0.5-4.0, p = 0.11) in the No-TLV group, though baseline and final Na levels were similar between groups. The mean change in eGFR was 2.6 ml/min/1.73 m2 (95%CI 10.1-15.3, p = 0.59) in TLV versus 7.5 ml/min/1.73 m2 (95%CI 5.2-20.2, p = 0.15) in No-TLV. TLV participants had significantly more urine output than No-TLV patients during their first 24 h after randomization (3294 vs 2155 ml, p = 0.043). CONCLUSION: TLV significantly increases urine output, with nominal improvement in Na level, in hyponatremic post-operative LVAD patients without adversely impacting renal function.
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BACKGROUND: Right heart catheterization for invasive hemodynamics has shown only modest correlation with clinical outcomes. We designed a novel hemodynamic variable that incorporates ventricular output and filling pressure. We anticipated that the aortic pulsatility index (API) would correlate with clinical outcomes in patients with heart failure. METHODS AND RESULTS: We retrospectively analyzed consecutive patients undergoing right heart catheterization with milrinone drug study at our institution (February 2013 to November 2019). The API was calculated as (systolic blood pressure - diastolic blood pressure)/pulmonary capillary wedge pressure. The primary outcome was freedom from advanced therapies, defined as the need for inotropes, temporary mechanical circulatory support, a left ventricular assist device, or orthotopic heart transplantation, or death at 30 days. A total of 224 patient encounters, age 57 years (48-66 years; 34% women; 31% ischemic cardiomyopathy) were included. In univariable analysis, lower baseline API was significantly associated with progression to advanced therapies or death at 30-days (odds ratio 0.43, 95% confidence interval 0.30-0.61; P < .001) compared with those on continued medical management. Receiver operator characteristic analysis specified an optimal cutpoint of 1.45 for API. A Kaplan-Meier analysis indicated an association of API with the primary outcome (79% for API ≥ 1.45 vs 48% for API < 1.45). In multivariable analysis, higher API was strongly associated with freedom from advanced therapies or death (odds ratio 0.38, 95% confidence interval 0.22-0.65, P ≤ .001), even when adjusted for baseline characteristics and routine right heart catheterization measurements. CONCLUSIONS: The API is a novel invasive hemodynamic measurement that is associated independently with freedom from advanced therapies or death at 30-day follow-up.
Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Pressão Propulsora Pulmonar , Estudos RetrospectivosRESUMO
PURPOSE OF REVIEW: The aim of this review is to discuss racial and sex disparities in the management and outcomes of patients with acute decompensated heart failure (ADHF). RECENT FINDINGS: Race and sex have a significant impact on in-hospital admissions and overall outcomes in patients with decompensated heart failure and cardiogenic shock. Black patients not only have a higher incidence of heart failure than other racial groups, but also higher admissions for ADHF and worse overall survival, while women receive less interventions for cardiogenic shock complicating acute myocardial infarction. Moreover, White patients are more likely than Black patients to be cared for by a cardiologist than a noncardiologist in the ICU, which has been linked to overall improved survival. In addition, recent data outline inherent racial and sex bias in the evaluation process for advanced heart failure therapies indicating that Black race negatively impacts referral for transplant, women are judged more harshly on their appearance, and that Black women are perceived to have less social support than others. This implicit bias in the evaluation process may impact appropriate timing of referral for advanced heart failure therapies. SUMMARY: Though significant racial and sex disparities exist in the management and treatment of patients with decompensated heart failure, these disparities are minimized when therapies are properly utilized and patients are treated according to guidelines.
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Insuficiência Cardíaca , Infarto do Miocárdio , Negro ou Afro-Americano , Feminino , Insuficiência Cardíaca/terapia , Humanos , Choque Cardiogênico/etiologia , Choque Cardiogênico/terapia , População BrancaRESUMO
Prostate cancer is a heterogeneous disease composed of divergent molecular and histologic subtypes, including prostate adenocarcinoma (PrAd) and neuroendocrine prostate cancer (NEPC). While PrAd is the major histology in prostate cancer, NEPC can evolve from PrAd as a mechanism of treatment resistance that involves a transition from an epithelial to a neurosecretory cancer phenotype. Cell surface markers are often associated with specific cell lineages and differentiation states in normal development and cancer. Here, we show that PrAd and NEPC can be broadly discriminated by cell-surface profiles based on the analysis of prostate cancer gene expression datasets. To overcome a dependence on predictions of human cell-surface genes and an assumed correlation between mRNA levels and protein expression, we integrated transcriptomic and cell-surface proteomic data generated from a panel of prostate cancer cell lines to nominate cell-surface markers associated with these cancer subtypes. FXYD3 and CEACAM5 were validated as cell-surface antigens enriched in PrAd and NEPC, respectively. Given the lack of effective treatments for NEPC, CEACAM5 appeared to be a promising target for cell-based immunotherapy. As a proof of concept, engineered chimeric antigen receptor T cells targeting CEACAM5 induced antigen-specific cytotoxicity in NEPC cell lines. Our findings demonstrate that the surfaceomes of PrAd and NEPC reflect unique cancer differentiation states and broadly represent vulnerabilities amenable to therapeutic targeting.
Assuntos
Antígenos de Superfície/análise , Antígenos de Superfície/imunologia , Carcinoma Neuroendócrino/terapia , Neoplasias da Próstata/terapia , Proteoma/análise , Linfócitos T/transplante , Transcriptoma , Antígeno Carcinoembrionário/genética , Antígeno Carcinoembrionário/imunologia , Antígeno Carcinoembrionário/metabolismo , Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/imunologia , Carcinoma Neuroendócrino/metabolismo , Diferenciação Celular , Células Cultivadas , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/imunologia , Proteínas Ligadas por GPI/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Imunoterapia , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/imunologia , Proteínas de Neoplasias/metabolismo , Próstata/imunologia , Próstata/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/metabolismo , Proteoma/imunologia , Linfócitos T/citologia , Linfócitos T/imunologiaRESUMO
BACKGROUND: Historically, invasive hemodynamic guidance was not superior compared to clinical assessment in patients admitted with acute decompensated heart failure (ADHF). This study assessed the accuracy of clinical assessment vs invasive hemodynamics in patients with ADHF. METHODS AND RESULTS: We conducted a prospective cohort study of patients admitted with ADHF. Prior to right-heart catheterization (RHC), physicians categorically predicted right atrial pressure, pulmonary capillary wedge pressure, cardiac index and hemodynamic profile (wet/dry, warm/cold) based on physical examination and clinical data evaluation (warmâ¯=â¯cardiac index > 2.2 L/min/m2; wetâ¯=â¯pulmonary capillary wedge pressure > 18 mmHg). We collected 218 surveys (of 83 cardiology fellows, 55 attending cardiologists, 45 residents, 35 interns) evaluating 97 patients. Of those patients, 46% were receiving inotropes prior to RHC. The positive and negative predictive values of clinical assessment compared to RHC for the cold and wet subgroups were 74.7% and 50.4%. The accuracy of categorical prediction was 43.6% for right atrial pressure, 34.4% for pulmonary capillary wedge pressure and 49.1% for cardiac index, and accuracy did not differ by clinician (P > 0.05 for all). Interprovider agreement was 44.4%. Therapeutic changes following RHC occurred in 71.1% overall (P < 0.001). CONCLUSIONS: Clinical assessment of patients with advanced heart failure presenting with ADHF has low accuracy across all training levels, with exaggerated rates of misrecognition of the most high-risk patients.
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Cateterismo Cardíaco/tendências , Tomada de Decisão Clínica , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/fisiologia , Médicos/normas , Idoso , Estudos de Coortes , Feminino , Insuficiência Cardíaca/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e QuestionáriosRESUMO
Mutationally activated kinases play an important role in the progression and metastasis of many cancers. Despite numerous oncogenic alterations implicated in metastatic prostate cancer, mutations of kinases are rare. Several lines of evidence suggest that nonmutated kinases and their pathways are involved in prostate cancer progression, but few kinases have been mechanistically linked to metastasis. Using a mass spectrometry-based phosphoproteomics dataset in concert with gene expression analysis, we selected over 100 kinases potentially implicated in human metastatic prostate cancer for functional evaluation. A primary in vivo screen based on overexpression of candidate kinases in murine prostate cells identified 20 wild-type kinases that promote metastasis. We queried these 20 kinases in a secondary in vivo screen using human prostate cells. Strikingly, all three RAF family members, MERTK, and NTRK2 drove the formation of bone and visceral metastasis confirmed by positron-emission tomography combined with computed tomography imaging and histology. Immunohistochemistry of tissue microarrays indicated that these kinases are highly expressed in human metastatic castration-resistant prostate cancer tissues. Our functional studies reveal the strong capability of select wild-type protein kinases to drive critical steps of the metastatic cascade, and implicate these kinases in possible therapeutic intervention.
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Neoplasias Ósseas/secundário , Neoplasias da Próstata/patologia , Proteínas Quinases/metabolismo , Vísceras/patologia , Animais , Neoplasias Ósseas/patologia , Osso e Ossos/patologia , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Humanos , Lentivirus , Pulmão/metabolismo , Masculino , Camundongos , Camundongos SCID , Proteínas de Neoplasias/metabolismo , Fosfoproteínas/metabolismo , Proteômica , Quinases da Família src/metabolismoRESUMO
Metastatic castration-resistant prostate cancer (CRPC) is the primary cause of prostate cancer-specific mortality. Defining new mechanisms that can predict recurrence and drive lethal CRPC is critical. Here, we demonstrate that localized high-risk prostate cancer and metastatic CRPC, but not benign prostate tissues or low/intermediate-risk prostate cancer, express high levels of nuclear Notch homolog 1, translocation-associated (Notch1) receptor intracellular domain. Chronic activation of Notch1 synergizes with multiple oncogenic pathways altered in early disease to promote the development of prostate adenocarcinoma. These tumors display features of epithelial-to-mesenchymal transition, a cellular state associated with increased tumor aggressiveness. Consistent with its activation in clinical CRPC, tumors driven by Notch1 intracellular domain in combination with multiple pathways altered in prostate cancer are metastatic and resistant to androgen deprivation. Our study provides functional evidence that the Notch1 signaling axis synergizes with alternative pathways in promoting metastatic CRPC and may represent a new therapeutic target for advanced prostate cancer.
Assuntos
Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptor Notch1/metabolismo , Transdução de Sinais , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Animais , Biomarcadores , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Expressão Gênica , Perfilação da Expressão Gênica , Xenoenxertos , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Proteínas Quinases Ativadas por Mitógeno , Gradação de Tumores , Metástase Neoplásica , Fenótipo , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Receptor Notch1/antagonistas & inibidores , Receptor Notch1/genética , Carga Tumoral , Quinases raf/metabolismo , Proteínas ras/metabolismoRESUMO
Evidence from numerous cancers suggests that increased aggressiveness is accompanied by up-regulation of signaling pathways and acquisition of properties common to stem cells. It is unclear if different subtypes of late-stage cancer vary in stemness properties and whether or not these subtypes are transcriptionally similar to normal tissue stem cells. We report a gene signature specific for human prostate basal cells that is differentially enriched in various phenotypes of late-stage metastatic prostate cancer. We FACS-purified and transcriptionally profiled basal and luminal epithelial populations from the benign and cancerous regions of primary human prostates. High-throughput RNA sequencing showed the basal population to be defined by genes associated with stem cell signaling programs and invasiveness. Application of a 91-gene basal signature to gene expression datasets from patients with organ-confined or hormone-refractory metastatic prostate cancer revealed that metastatic small cell neuroendocrine carcinoma was molecularly more stem-like than either metastatic adenocarcinoma or organ-confined adenocarcinoma. Bioinformatic analysis of the basal cell and two human small cell gene signatures identified a set of E2F target genes common between prostate small cell neuroendocrine carcinoma and primary prostate basal cells. Taken together, our data suggest that aggressive prostate cancer shares a conserved transcriptional program with normal adult prostate basal stem cells.
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Perfilação da Expressão Gênica , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Células-Tronco/metabolismo , Antígenos CD/metabolismo , Células Epiteliais/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Masculino , Glândulas Mamárias Humanas/citologia , Metástase Neoplásica , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/patologia , Fenótipo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Análise de Sequência de RNA , Transdução de Sinais/genética , Fatores de Transcrição/metabolismoRESUMO
With the goal of decreasing low-density cholesterol (LDL-C) to mitigate risk of both primary and secondary cardiovascular outcomes, statins have been the cornerstone of therapy, significantly reducing the incidence of coronary atherosclerotic vascular disease. Previous studies suggest that adding other non-statin LDL-lowering agents may further lower LDL-C without negative side effects. Recent guidelines support the hypothesis that driving the LDL-C level below previously recommended targets may have a beneficial effect. Ezetimibe, a cholesterol absorption blocker that inhibits the Niemann-Pick C1-Like 1 (NPC1L1) receptor, has been the focus of recent trials that support its use in cardiovascular risk reduction. For patients not at goal on statin therapy alone, ezetimibe has proven to be a safe, well-tolerated medication that may be used as an adjunct to statin therapy to further reduce LDL-C, resulting in a significant mortality benefit.
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Anticolesterolemiantes/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Ezetimiba/uso terapêutico , LDL-Colesterol/sangue , Humanos , Metabolismo dos Lipídeos , Fatores de RiscoRESUMO
There is a clinical need for imaging technologies that can accurately detect cell death in a multitude of pathological conditions. Zinc(II)-bis(dipicolylamine) (Zn2BDPA) coordination complexes are known to associate with the anionic phosphatidylserine that is exposed on the surface of dead and dying cells, and fluorescent monovalent Zn2BDPA probes are successful cell death imaging agents. This present study compared the membrane targeting ability of two structurally related deep-red fluorescent probes, bis-Zn2BDPA-SR and tetra-Zn2BDPA-SR, with two and four appended Zn2BDPA units, respectively. Vesicle and cell microscopy studies indicated that a higher number of Zn2BDPA targeting units improved probe selectivity for phosphatidylserine-rich vesicles, and increased probe localization at the plasma membrane of dead and dying cells. The fluorescent probes were also tested in three separate animal models, (1) necrotic prostate tumor rat model, (2) thymus atrophy mouse model, and (3) traumatic brain injury mouse model. In each case, there was more tetra-Zn2BDPA-SR accumulation at the site of cell death than bis-Zn2BDPA-SR. The results indicate that multivalent Zn2BDPA probes are promising molecules for effective imaging of cell death processes in cell culture and in living subjects.
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Aminas/química , Morte Celular/fisiologia , Diagnóstico por Imagem/métodos , Corantes Fluorescentes/química , Ácidos Picolínicos/química , Zinco/química , Animais , Lesões Encefálicas/patologia , Linhagem Celular , Humanos , Masculino , Camundongos , Neoplasias da Próstata/patologia , Ratos , Timo/patologiaRESUMO
PURPOSE: Small cell lung cancer (SCLC) is an aggressive disease with limited treatment options. Delta-like ligand 3 (DLL3) is highly expressed on SCLC and several other types of neuroendocrine cancers, with limited normal tissue RNA expression in brain, pituitary, and testis, making it a promising CAR T-cell target for SCLC and other solid tumor indications. EXPERIMENTAL DESIGN: A large panel of anti-DLL3 scFv-based CARs were characterized for both in vitro and in vivo activity. To understand the potential for pituitary and brain toxicity, subcutaneous or intracranial tumors expressing DLL3 were implanted in mice and treated with mouse cross-reactive DLL3 CAR T cells. RESULTS: A subset of CARs demonstrated high sensitivity for targets with low DLL3 density and long-term killing potential in vitro. Infusion of DLL3 CAR T cells led to robust antitumor efficacy, including complete responses, in subcutaneous and systemic SCLC in vivo models. CAR T-cell infiltration into intermediate and posterior pituitary was detected, but no tissue damage in brain or pituitary was observed, and the hormone-secretion function of the pituitary was not ablated. CONCLUSIONS: In summary, the preclinical efficacy and safety data presented here support further evaluation of DLL3 CAR T cells as potential clinical candidates for the treatment of SCLC.
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Transplante de Células-Tronco Hematopoéticas , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Animais , Masculino , Camundongos , Ligantes , Neoplasias Pulmonares/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/genética , Linfócitos T/metabolismoRESUMO
Cell death is a critically important biological process. Disruption of homeostasis, either by excessive or deficient cell death, is a hallmark of many pathological conditions. Recent research advances have greatly increased our molecular understanding of cell death and its role in a range of diseases and therapeutic treatments. Central to these ongoing research and clinical efforts is the need for imaging technologies that can locate and identify cell death in a wide array of in vitro and in vivo biomedical samples with varied spatiotemporal requirements. This review article summarizes community efforts over the past five years to identify useful biomarkers for dead and dying cells, and to develop molecular probes that target these biomarkers for optical, radionuclear, or magnetic resonance imaging. Apoptosis biomarkers are classified as either intracellular (caspase enzymes, mitochondrial membrane potential, cytosolic proteins) or extracellular (plasma membrane phospholipids, membrane potential, surface exposed histones). Necrosis, autophagy, and senescence biomarkers are described, as well as unexplored cell death biomarkers. The article discusses possible chemotherapeutic and theranostic strategies, and concludes with a summary of current challenges and expected eventual rewards of clinical cell death imaging.
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Imagem Molecular/métodos , Sondas Moleculares/metabolismo , Terapia de Alvo Molecular/métodos , Animais , Biomarcadores/metabolismo , Morte Celular , HumanosRESUMO
Eight fluorescent squaraine rotaxanes with deep-red absorption/emission wavelengths were prepared and assessed for chemical stability and suitability as water-soluble, fluorescent tracers. The most stable squaraine rotaxanes have four large stopper groups attached to the ends of the encapsulated squaraine, and two members of this structural class have promise as highly fluorescent tracers with rapid renal clearance and very low tissue uptake in living mice.
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Ciclobutanos/química , Corantes Fluorescentes/química , Fenóis/química , Rotaxanos/química , Água/química , Absorção , Animais , Transporte Biológico , Ciclobutanos/metabolismo , Corantes Fluorescentes/metabolismo , Camundongos , Modelos Moleculares , Conformação Molecular , Fenóis/metabolismo , Rotaxanos/metabolismo , SolubilidadeRESUMO
A series of fluorescent phosphatidylserine and phosphatidylcholine derivatives were prepared and evaluated by cell microscopy for ability to translocate across mammalian plasma membranes via the putative aminophospholipid flippase. Phosphatidylserine derivatives, with either a neutral 7-nitrobenz-2-oxa-1,3-diazol-4-yl (NBD) or a coumarin fluorophore appended to the 2-acyl chain, entered the cytosol of all three cell lines tested and control experiments showed that the translocation was due to flippase activity. In contrast, a phosphatidylserine conjugate containing a charged and polar carboxyfluorescein was not translocated and remained in the cell plasma membrane. The phosphatidylserine-coumarin derivative exhibits bright fluorescence and higher photostability than the NBD analogues, and thus is a promising new fluorescent probe for extended-imaging studies of flippase action in living cells using laser confocal microscopes.
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Corantes Fluorescentes/metabolismo , Fosfatidilserinas/metabolismo , Proteínas de Transferência de Fosfolipídeos/metabolismo , Animais , Azóis/metabolismo , Transporte Biológico , Linhagem Celular , Cumarínicos/metabolismo , Fluoresceínas/metabolismo , Nitrobenzenos/metabolismoRESUMO
A synthetic, near-infrared, fluorescent probe, named PSS-794 was assessed for its ability to detect cell death in two animal models. The molecular probe contains a zinc(II)-dipicolylamine (Zn(2+)-DPA) affinity ligand that selectively targets exposed phosphatidylserine on the surface of dead and dying cells. The first animal model used rats that were treated with dexamethasone to induce thymic atrophy. Ex vivo fluorescence imaging and histological analysis of excised organs showed thymus uptake of PSS-794 was four times higher than a control fluorophore that lacked the Zn(2+)-DPA affinity ligand. In addition, the presence of PSS-794 produced a delayed and higher build up of dead and dying cells in the rat thymus. The second animal model employed focal beam radiation to induce cell death in tumor-bearing rats. Whole-body and ex vivo imaging showed that the amount of PSS-794 in a radiation-treated tumor was almost twice that in a non-treated tumor. The results indicate that PSS-794 may be useful for preclinical optical detection of tumor cell death due to therapy.
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Corantes Fluorescentes/metabolismo , Técnicas de Sonda Molecular , Sondas Moleculares/metabolismo , Animais , Caspase 3/metabolismo , Morte Celular , Corantes Fluorescentes/química , Masculino , Microscopia de Fluorescência , Sondas Moleculares/química , Radiação , Ratos , Ratos Wistar , Timo/citologia , Timo/enzimologia , Distribuição TecidualRESUMO
Cell death is a fundamental biological process that is present in numerous disease pathologies. Fluorescent probes that detect cell death have been developed for a myriad of research applications ranging from microscopy to in vivo imaging. Here we describe a synthetic near-infrared (NIR) conjugate of zinc(II)-dipicolylamine (Zn²+-DPA) for in vivo imaging of cell death. Chemically induced in vivo models of myopathy were established using an ionphore, ethanol, or ketamine as cytotoxins. The Zn²+-DPA fluorescent probe or corresponding control was subsequently injected, and whole animal fluorescence imaging demonstrated probe uptake at the site of muscle damage, which was confirmed by ex vivo and histological analyses. Further, a comparative study with a NIR fluorescent conjugate Annexin V showed less intense uptake at the site of muscle damage and high accumulation in the bladder. The results indicate that the fluorescent Zn²+-DPA conjugate is an effective probe for in vivo cell death detection and in some cases may be an appropriate alternative to fluorescent Annexin V conjugates.