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2.
Immunity ; 56(8): 1844-1861.e6, 2023 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-37478855

RESUMEN

Obesity is a major risk factor for psoriasis, but how obesity disrupts the regulatory mechanisms that keep skin inflammation in check is unclear. Here, we found that skin was enriched with a unique population of CD4+Foxp3+ regulatory T (Treg) cells expressing the nuclear receptor peroxisome proliferation-activated receptor gamma (PPARγ). PPARγ drove a distinctive transcriptional program and functional suppression of IL-17A+ γδ T cell-mediated psoriatic inflammation. Diet-induced obesity, however, resulted in a reduction of PPARγ+ skin Treg cells and a corresponding loss of control over IL-17A+ γδ T cell-mediated inflammation. Mechanistically, PPARγ+ skin Treg cells preferentially took up elevated levels of long-chain free fatty acids in obese mice, which led to cellular lipotoxicity, oxidative stress, and mitochondrial dysfunction. Harnessing the anti-inflammatory properties of these PPARγ+ skin Treg cells could have therapeutic potential for obesity-associated inflammatory skin diseases.


Asunto(s)
Psoriasis , Linfocitos T Reguladores , Animales , Ratones , PPAR gamma , Interleucina-17 , Piel , Psoriasis/inducido químicamente , Inflamación , Obesidad
3.
J Control Release ; 357: 655-668, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37080489

RESUMEN

The wide prevalence of BRAF mutations in diagnosed melanomas drove the clinical advancement of BRAF inhibitors in combination with immune checkpoint blockade for treatment of advanced disease. However, deficits in therapeutic potencies and safety profiles motivate the development of more effective strategies that improve the combination therapy's therapeutic index. Herein, we demonstrate the benefits of a locoregional chemoimmunotherapy delivery system, a novel thermosensitive hydrogel comprised of gelatin and Pluronic® F127 components already widely used in humans in both commercial and clinical products, for the co-delivery of a small molecule BRAF inhibitor with immune checkpoint blockade antibody for the treatment of BRAF-mutated melanoma. In vivo evaluation of administration route and immune checkpoint target effects revealed intratumoral administration of antagonistic programmed cell death protein 1 antibody (aPD-1) lead to potent antitumor therapy in combination with BRAF inhibitor vemurafenib. The thermosensitive F127-g-Gelatin hydrogel that was evaluated in multiple murine models of BRAF-mutated melanoma that facilitated prolonged local drug release within the tumor (>1 week) substantially improved local immunomodulation, tumor control, rates of tumor response, and animal survival. Thermosensitive F127-g-Gelatin hydrogels thus improve upon the clinical benefits of vemurafenib and aPD-1 in a locoregional chemoimmunotherapy approach for the treatment of BRAF-mutated melanoma.


Asunto(s)
Melanoma , Proteínas Proto-Oncogénicas B-raf , Humanos , Animales , Ratones , Vemurafenib/uso terapéutico , Proteínas Proto-Oncogénicas B-raf/genética , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Hidrogeles/uso terapéutico , Gelatina , Preparaciones de Acción Retardada/uso terapéutico , Melanoma/tratamiento farmacológico , Melanoma/genética , Inhibidores de Proteínas Quinasas , Mutación
5.
JAAD Int ; 7: 7-12, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35243403

RESUMEN

Myotonic dystrophy types 1 and 2 are a group of complex genetic disorders resulting from the expansion of (CTG)n nucleotide repeats in the DMPK gene. In addition to the hallmark manifestations of myotonia and skeletal muscle atrophy, myotonic dystrophy also affects a myriad of other organs including the heart, lungs, as well as the skin. The most common cutaneous manifestations of myotonic dystrophy are early male frontal alopecia and adult-onset pilomatricomas. Myotonic dystrophy also increases the risk of developing malignant skin diseases such as basal cell carcinoma and melanoma. To aid in the diagnosis and treatment of myotonic dystrophy related skin conditions, it is important for the dermatologist to become cognizant of the common and rare cutaneous manifestations of this genetic disorder. We performed a PubMed search using the key terms "myotonic dystrophy" AND "cutaneous" OR "skin" OR "dermatologic" AND "manifestation" OR "finding." The resulting publications were manually reviewed for additional relevant publications, and subsequent additional searches were performed as needed, especially regarding the molecular mechanisms of pathogenesis. In this review, we aim to provide an overview of myotonic dystrophy types 1 and 2 and summarize their cutaneous manifestations as well as potential mechanisms of pathogenesis.

6.
Nat Commun ; 12(1): 2624, 2021 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-33976143

RESUMEN

The etiology of ulcerative colitis is poorly understood and is likely to involve perturbation of the complex interactions between the mucosal immune system and the commensal bacteria of the gut, with cytokines acting as important cross-regulators. Here we use IFN receptor-deficient mice in a dextran sulfate sodium (DSS) model of acute intestinal injury to study the contributions of type I and III interferons (IFN) to the initiation, progression and resolution of acute colitis. We find that mice lacking both types of IFN receptors exhibit enhanced barrier destruction, extensive loss of goblet cells and diminished proliferation of epithelial cells in the colon following DSS-induced damage. Impaired mucosal healing in double IFN receptor-deficient mice is driven by decreased amphiregulin expression, which IFN signaling can up-regulate in either the epithelial or hematopoietic compartment. Together, these data underscore the pleiotropic functions of IFNs and demonstrate that these critical antiviral cytokines also support epithelial regeneration following acute colonic injury.


Asunto(s)
Colitis Ulcerosa/inmunología , Interferones/metabolismo , Mucosa Intestinal/patología , Repitelización/inmunología , Animales , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/patología , Sulfato de Dextran/administración & dosificación , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Células Epiteliales , Femenino , Humanos , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/inmunología , Masculino , Ratones , Ratones Noqueados , Receptor de Interferón alfa y beta/genética , Receptor de Interferón alfa y beta/metabolismo , Receptores de Interferón/genética , Receptores de Interferón/metabolismo , Transducción de Señal/genética , Transducción de Señal/inmunología , Organismos Libres de Patógenos Específicos
7.
J Am Acad Dermatol ; 85(6): 1565-1570, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33422628

RESUMEN

Though known as a medicinal herb for centuries, the recent legalization of cannabinoids across many states has ushered in a new era where cannabinoids have become a popular treatment option among clinicians and patients alike. Cannabinoids have demonstrated efficacy in wound healing, reducing inflammation, ameliorating pain, and have shown potential as an antitumor agent. As a result, cannabinoids have been rapidly woven into the fabric of modern medicine. However, the utility of cannabinoids in dermatologic surgery has not been explored to date. In this article, we review the current literature to discuss the potential impact of cannabinoid use in dermatologic surgery.


Asunto(s)
Cannabidiol , Cannabinoides , Procedimientos Quirúrgicos Dermatologicos/métodos , Cannabinoides/efectos adversos , Humanos
8.
Cancer Res ; 81(4): 1171-1177, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33355190

RESUMEN

Whole-slide histology images contain information that is valuable for clinical and basic science investigations of cancer but extracting quantitative measurements from these images is challenging for researchers who are not image analysis specialists. In this article, we describe HistomicsML2, a software tool for learn-by-example training of machine learning classifiers for histologic patterns in whole-slide images. This tool improves training efficiency and classifier performance by guiding users to the most informative training examples for labeling and can be used to develop classifiers for prospective application or as a rapid annotation tool that is adaptable to different cancer types. HistomicsML2 runs as a containerized server application that provides web-based user interfaces for classifier training, validation, exporting inference results, and collaborative review, and that can be deployed on GPU servers or cloud platforms. We demonstrate the utility of this tool by using it to classify tumor-infiltrating lymphocytes in breast carcinoma and cutaneous melanoma. SIGNIFICANCE: An interactive machine learning tool for analyzing digital pathology images enables cancer researchers to apply this tool to measure histologic patterns for clinical and basic science studies.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Aprendizaje Automático , Neoplasias/diagnóstico , Neoplasias/patología , Programas Informáticos , Algoritmos , Investigación Biomédica/métodos , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/patología , Conjuntos de Datos como Asunto , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Linfocitos Infiltrantes de Tumor/patología , Oncología Médica/métodos , Melanoma/diagnóstico , Melanoma/patología , Valor Predictivo de las Pruebas , Pronóstico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/patología , Melanoma Cutáneo Maligno
9.
Sci Transl Med ; 12(563)2020 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-32998971

RESUMEN

Systemic administration of immune checkpoint blockade (ICB) monoclonal antibodies (mAbs) can unleash antitumor functions of T cells but is associated with variable response rates and off-target toxicities. We hypothesized that antitumor efficacy of ICB is limited by the minimal accumulation of mAb within tissues where antitumor immunity is elicited and regulated, which include the tumor microenvironment (TME) and secondary lymphoid tissues. In contrast to systemic administration, intratumoral and intradermal routes of administration resulted in higher mAb accumulation within both the TME and its draining lymph nodes (LNs) or LNs alone, respectively. The use of either locoregional administration route resulted in pronounced T cell responses from the ICB therapy, which developed in the secondary lymphoid tissues and TME of treated mice. Targeted delivery of mAb to tumor-draining lymph nodes (TdLNs) alone was associated with enhanced antitumor immunity and improved therapeutic effects compared to conventional systemic ICB therapy, and these effects were sustained at reduced mAb doses and comparable to those achieved by intratumoral administration. These data suggest that locoregional routes of administration of ICB mAb can augment ICB therapy by improving immunomodulation within TdLNs.


Asunto(s)
Inmunoterapia , Neoplasias , Animales , Ganglios Linfáticos , Ratones , Neoplasias/terapia , Linfocitos T , Microambiente Tumoral
10.
NPJ Precis Oncol ; 3: 27, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31701018

RESUMEN

Propranolol is a widely used beta blocker that consists of a racemic mixture of R and S stereoisomers. Only the S stereoisomer has significant activity against the beta-adrenergic receptor. A fortuitous clinical observation was made in an infant who received propranolol for cardiac disease, and regression of a hemangioma of infancy was noted. This has led to the widespread use of propranolol for the treatment of large and life-threatening hemangiomas of infancy. Infants receiving propranolol require monitoring to ensure that they do not suffer from side effects related to beta blockade. The exact mechanism of activity of propranolol in hemangioma of infancy is unknown. In this study, we treated hemangioma stem cells with both beta blockade active S- and inactive R-propranolol and looked for genes that were coordinately regulated by this treatment. Among the genes commonly downregulated, Angiopoietin-like 4 (ANGPTL4) was among the most regulated. We confirmed that propranolol isomers downregulated ANGPTL4 in endothelial cells, with greater downregulation of ANGPTL4 using the beta blockade inactive R-propranolol. ANGPTL4 is present in human hemangiomas of infancy. Finally, R-propranolol inhibited the growth of bEnd.3 hemangioma cells in vivo. The implication of this is that hemangioma growth can be blocked without the side effects of beta blockade. Given that humans have been exposed to racemic propranolol for decades and thus to R-propranolol, clinical development of R-propranolol for hemangiomas of infancy and other angiogenic diseases is warranted.

11.
Mol Cancer Res ; 17(12): 2395-2409, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31548239

RESUMEN

Molecular events activating the PI3K pathway are frequently detected in human tumors and the activation of PI3K signaling alters numerous cellular processes including tumor cell proliferation, survival, and motility. More recent studies have highlighted the impact of PI3K signaling on the cellular response to interferons and other immunologic processes relevant to antitumor immunity. Given the ability of IFNγ to regulate antigen processing and presentation and the pivotal role of MHC class I (MHCI) and II (MHCII) expression in T-cell-mediated antitumor immunity, we sought to determine the impact of PI3K signaling on MHCI and MHCII induction by IFNγ. We found that the induction of cell surface MHCI and MHCII molecules by IFNγ is enhanced by the clinical grade PI3K inhibitors dactolisib and pictilisib. We also found that PI3K inhibition increases STAT1 protein levels following IFNγ treatment and increases accessibility at genomic STAT1-binding motifs. Conversely, we found that pharmacologic activation of PI3K signaling can repress the induction of MHCI and MHCII molecules by IFNγ, and likewise, the loss of PTEN attenuates the induction of MHCI, MHCII, and STAT1 by IFNγ. Consistent with these in vitro studies, we found that within human head and neck squamous cell carcinomas, intratumoral regions with high phospho-AKT IHC staining had reduced MHCI IHC staining. IMPLICATIONS: Collectively, these findings demonstrate that MHC expression can be modulated by PI3K signaling and suggest that activation of PI3K signaling may promote immune escape via effects on antigen presentation.


Asunto(s)
Interferón gamma/farmacología , Fosfatidilinositol 3-Quinasa/genética , Factor de Transcripción STAT1/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Presentación de Antígeno/genética , Presentación de Antígeno/inmunología , Sitios de Unión/genética , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica/genética , Regulación Neoplásica de la Expresión Génica/inmunología , Genes MHC Clase I/genética , Genes MHC Clase I/inmunología , Genes MHC Clase II/genética , Genes MHC Clase II/inmunología , Genómica , Humanos , Interferón gamma/genética , Fosfohidrolasa PTEN/genética , Fosfatidilinositol 3-Quinasa/inmunología , Unión Proteica/genética , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-akt/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/inmunología , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/inmunología , Carcinoma de Células Escamosas de Cabeza y Cuello/patología
12.
Sci Rep ; 9(1): 3255, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30824801

RESUMEN

IGF1R and CD44 are overexpressed in most advanced melanomas so we designed chemotherapeutic nanoparticles to target those receptors. Tris(dibenzylideneacetone)dipalladium (Tris DBA-Pd) is a novel inhibitor of N-myristoyltransferase 1 (NMT-1) and has proven in vivo activity against melanoma. However, poor solubility impairs its effectiveness. To improve its therapeutic efficacy and overcome drug resistance in advanced melanomas, we synthesized Tris DBA-Pd hyaluronic acid nanoparticles (Tris DBA-Pd HANP) and evaluated them against in vivo xenografts of LM36R, an aggressive BRAF mutant human melanoma resistant to BRAF inhibitors. We treated xenografted mice in four arms: empty HANPs, free Tris DBA-Pd, Tris DBA-Pd HANPs, and Tris DBA-Pd HANPs with IGF1R antibody. The Tris DBA-Pd HANP group was the most responsive to treatment and showed the greatest depletion of CD44-positive cells on IHC. Surprisingly, the HANP containing IGF1R antibody was less effective than particles without antibody, possibly due to steric hindrance of IGF1R and CD44 binding. Tris DBA-Pd nanoparticles are an effective therapy for CD44-positive tumors like melanoma, and further development of these nanoparticles should be pursued.


Asunto(s)
Melanoma/patología , Melanoma/terapia , Nanopartículas del Metal/uso terapéutico , Paladio/uso terapéutico , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Receptores de Hialuranos/metabolismo , Ácido Hialurónico/química , Masculino , Ratones Desnudos , Estadificación de Neoplasias , Compuestos Organometálicos/química , Tamaño de la Partícula , Transcriptoma/genética , Regulación hacia Arriba/genética , Ensayos Antitumor por Modelo de Xenoinjerto
13.
J Vasc Surg ; 68(6S): 137S-151S.e2, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30104096

RESUMEN

OBJECTIVE: Regenerative medicine seeks to stall or to reverse the pathologic consequences of chronic diseases. Many people with diabetes have peripheral arterial disease (PAD), which increases their already high risk of major amputation. Cellular therapies are a promising regenerative medicine approach to PAD that can be used to focally inject regenerative cells to endangered tissue beds. Mesenchymal stem cells (MSCs) are known to promote tissue regeneration through stromal support and paracrine stimulation of new blood vessels (angiogenesis). Whereas little is known about human diabetic MSCs (dMSCs), particularly those from patients with PAD, dMSCs have a limited expansion capacity but can be improved with human platelet lysate (PL) supplementation. PL is rich in many growth factors, including epidermal growth factor (EGF), which is known to be important to cell proliferation and survival signaling pathways. We hypothesize that dMSCs have a reversible defect in EGF receptor pathways. The objective of this work was to test this hypothesis using dMSCs from PAD patients. METHODS: The secretome expression of EGF and prominent angiogens was characterized from bone marrow (BM)-derived and adipose tissue-derived (ATD) dMSCs from five patients (six limbs) undergoing major amputation. Western blot was used to characterize the AKT and extracellular signal-regulated protein kinases 1 and 2 expression in dMSCs under standard culture (5% fetal bovine serum plus fibroblast growth factor 2 [FGF2]), 5% human PL, or 5% fetal bovine serum plus EGF. Healthy donor MSCs were control cells. The angiogenic activity of BM- and ATD-dMSCs was tested on human umbilical vein endothelial cells (ECs). Paired t-test, analysis of variance, and Kruskal-Wallis tests were used as appropriate. RESULTS: Both BM- and ATD-dMSCs had typical MSC surface marker expression and similar expansion profiles, and they did not express EGF in their secretome. PL supplementation of dMSCs improved AKT signaling, but they were resistant to FGF2 activation of extracellular signal-regulated protein kinases 1 and 2. EGF supplementation led to similar AKT expression as with PL, but PL had greater phosphorylation of AKT at 30 and 60 minutes. The conditioned media from both BM- and ATD-dMSCs had robust levels of prominent angiogens (vascular endothelial growth factor, monocyte chemoattractant protein 1, hepatocyte growth factor), which stimulated EC proliferation and migration, and the co-culture of dMSCs with ECs led to significantly longer EC sprouts in three-dimensional gel than EC-alone pellets. CONCLUSIONS: PL and EGF supplementation improves AKT expression in dMSCs over that of FGF2, but PL improved pAKT over that of EGF. Thus, PL supplementation strategies may improve AKT signaling, which could be important to MSC survival in cellular therapies. Furthermore, BM- and ATD-dMSCs have similar secretomes and robust in vitro angiogenic activity, which supports pursuing dMSCs from both reservoirs in regenerative medicine strategies.


Asunto(s)
Tejido Adiposo/citología , Células de la Médula Ósea/metabolismo , Angiopatías Diabéticas/metabolismo , Células Madre Mesenquimatosas/metabolismo , Neovascularización Fisiológica , Enfermedad Arterial Periférica/metabolismo , Transducción de Señal , Anciano , Amputación Quirúrgica , Plaquetas/metabolismo , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/patología , Extractos Celulares/farmacología , Movimiento Celular , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Angiopatías Diabéticas/patología , Angiopatías Diabéticas/cirugía , Factor de Crecimiento Epidérmico/farmacología , Femenino , Factor 2 de Crecimiento de Fibroblastos/farmacología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Masculino , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/patología , Persona de Mediana Edad , Enfermedad Arterial Periférica/patología , Enfermedad Arterial Periférica/cirugía , Fenotipo , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Vías Secretoras
14.
J Clin Pharmacol ; 58(1): 7-24, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29136276

RESUMEN

Two pharmacologic approaches that are currently at the forefront of treating advanced cancer are those that center on disrupting critical growth/survival signaling pathways within tumor cells (commonly referred to as "targeted therapies") and those that center on enhancing the capacity of a patient's immune system to mount an antitumor response (immunotherapy). Maximizing responses to both of these approaches requires an understanding of the oncogenic events present in a given patient's tumor and the nature of the tumor-immune microenvironment. Although these 2 modalities were developed and initially used independently, combination regimens are now being tested in clinical trials, underscoring the need to understand how targeted therapies influence immunologic events. Translational studies and preclinical models have demonstrated that targeted therapies can influence immune cell trafficking, the production of and response to chemokines and cytokines, antigen presentation, and other processes relevant to antitumor immunity and immune homeostasis. Moreover, because these and other effects of targeted therapies occur in nonmalignant cells, targeted therapies are being evaluated for use in applications outside of oncology.


Asunto(s)
Neoplasias/tratamiento farmacológico , Neoplasias/inmunología , Animales , Humanos , Inmunoterapia/métodos , Oncología Médica/métodos , Terapia Molecular Dirigida/métodos , Neoplasias/terapia
15.
Melanoma Manag ; 4(1): 13-37, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28758010

RESUMEN

Melanoma is usually apparent on the skin and readily detected by trained medical providers using a routine total body skin examination, yet this malignancy is responsible for the majority of skin cancer-related deaths. Currently, there is no national consensus on skin cancer screening in the USA, but dermatologists and primary care providers are routinely confronted with making the decision about when to recommend total body skin examinations and at what interval. The objectives of this paper are: to propose rational, risk-based, data-driven guidelines commensurate with the US Preventive Services Task Force screening guidelines for other disorders; to compare our proposed guidelines to recommendations made by other national and international organizations; and to review the US Preventive Services Task Force's 2016 Draft Recommendation Statement on skin cancer screening.

16.
J Biol Chem ; 292(24): 10142-10152, 2017 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-28468827

RESUMEN

Contributions of metabolic changes to cancer development and maintenance have received increasing attention in recent years. Although many human cancers share similar metabolic alterations, it remains unclear whether oncogene-specific metabolic alterations are required for tumor development. Using an RNAi-based screen targeting the majority of the known metabolic proteins, we recently found that oncogenic BRAFV600E up-regulates HMG-CoA lyase (HMGCL), which converts HMG-CoA to acetyl-CoA and a ketone body, acetoacetate, that selectively enhances BRAFV600E-dependent MEK1 activation in human cancer. Here, we identified HMG-CoA synthase 1 (HMGCS1), the upstream ketogenic enzyme of HMGCL, as an additional "synthetic lethal" partner of BRAFV600E Although HMGCS1 expression did not correlate with BRAFV600E mutation in human melanoma cells, HMGCS1 was selectively important for proliferation of BRAFV600E-positive melanoma and colon cancer cells but not control cells harboring active N/KRAS mutants, and stable knockdown of HMGCS1 only attenuated colony formation and tumor growth potential of BRAFV600E melanoma cells. Moreover, cytosolic HMGCS1 that co-localized with HMGCL and BRAFV600E was more important than the mitochondrial HMGCS2 isoform in BRAFV600E-expressing cancer cells in terms of acetoacetate production. Interestingly, HMGCL knockdown did not affect HMGCS1 expression levels, whereas HMGCS1 knockdown caused a compensating increase in HMGCL protein level because of attenuated protein degradation. However, this increase did not reverse the reduced ketogenesis in HMGCS1 knockdown cells. Mechanistically, HMGCS1 inhibition decreased intracellular acetoacetate levels, leading to reduced BRAFV600E-MEK1 binding and consequent MEK1 activation. We conclude that the ketogenic HMGCS1-HMGCL-acetoacetate axis may represent a promising therapeutic target for managing BRAFV600E-positive human cancers.


Asunto(s)
Neoplasias del Colon/enzimología , Hidroximetilglutaril-CoA Sintasa/metabolismo , MAP Quinasa Quinasa 1/metabolismo , Melanoma/enzimología , Proteínas de Neoplasias/metabolismo , Oxo-Ácido-Liasas/metabolismo , Proteínas Proto-Oncogénicas B-raf/metabolismo , Acetoacetatos/metabolismo , Sustitución de Aminoácidos , Animales , Línea Celular Tumoral , Proliferación Celular , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Citosol/enzimología , Citosol/metabolismo , Activación Enzimática , Estabilidad de Enzimas , Femenino , Humanos , Hidroximetilglutaril-CoA Sintasa/antagonistas & inhibidores , Hidroximetilglutaril-CoA Sintasa/genética , Isoenzimas/antagonistas & inhibidores , Isoenzimas/genética , Isoenzimas/metabolismo , MAP Quinasa Quinasa 1/química , Melanoma/metabolismo , Melanoma/patología , Ratones Desnudos , Mutación , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Trasplante de Neoplasias , Oxo-Ácido-Liasas/antagonistas & inhibidores , Oxo-Ácido-Liasas/química , Oxo-Ácido-Liasas/genética , Proteolisis , Proteínas Proto-Oncogénicas B-raf/genética , Interferencia de ARN , Carga Tumoral
17.
Cell Metab ; 25(2): 358-373, 2017 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-28089569

RESUMEN

Lifestyle factors, including diet, play an important role in the survival of cancer patients. However, the molecular mechanisms underlying pathogenic links between diet and particular oncogenic mutations in human cancers remain unclear. We recently reported that the ketone body acetoacetate selectively enhances BRAF V600E mutant-dependent MEK1 activation in human cancers. Here we show that a high-fat ketogenic diet increased serum levels of acetoacetate, leading to enhanced tumor growth potential of BRAF V600E-expressing human melanoma cells in xenograft mice. Treatment with hypolipidemic agents to lower circulating acetoacetate levels or an inhibitory homolog of acetoacetate, dehydroacetic acid, to antagonize acetoacetate-BRAF V600E binding attenuated BRAF V600E tumor growth. These findings reveal a signaling basis underlying a pathogenic role of dietary fat in BRAF V600E-expressing melanoma, providing insights into the design of conceptualized "precision diets" that may prevent or delay tumor progression based on an individual's specific oncogenic mutation profile.


Asunto(s)
Grasas de la Dieta/efectos adversos , Cuerpos Cetónicos/metabolismo , Melanoma/patología , Mutación/genética , Proteínas Proto-Oncogénicas B-raf/genética , Ácido 3-Hidroxibutírico/farmacología , Acetoacetatos/administración & dosificación , Acetoacetatos/sangre , Acetoacetatos/farmacología , Animales , Proliferación Celular/efectos de los fármacos , Femenino , Humanos , Hipolipemiantes/farmacología , Inyecciones Intraperitoneales , Melanoma/sangre , Ratones , Ratones Desnudos , Pironas/química , Pironas/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Front Pharmacol ; 7: 327, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27729860

RESUMEN

Advances in molecular pathology have changed the landscape of oncology. The ability to interrogate tissue samples for oncogene amplification, driver mutations, and other molecular alterations provides clinicians with an enormous level of detail about their patient's cancer. In some cases, this information informs treatment decisions, especially those related to targeted anti-cancer therapies. However, in terms of immune-based therapies, it is less clear how to use such information. Likewise, despite studies demonstrating the pivotal role of neoantigens in predicting responsiveness to immune checkpoint blockade, it is not known if the expression of neoantigens impacts the response to targeted therapies despite a growing recognition of their diverse effects on immunity. To realize the promise of 'personalized medicine', it will be important to develop a more integrated understanding of the relationships between oncogenic events and processes governing anti-tumor immunity. One area of investigation to explore such relationships centers on defining how ErbB/HER activation and signal transduction influences antigen processing and presentation.

19.
Dermatol Online J ; 22(6)2016 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-27617615

RESUMEN

BACKGROUND: Botulinum toxin type A (BTX-A) injections are an effective treatment for controlling hyperhidrosis at sites of amputation. Hyperesthesia associated with amputated limbs is a major barrier to performing this procedure under local anesthesia. OBJECTIVE: To present a novel method for improving local anesthesia with BTX-A injections. Methods & RESULTS: A 29-year-old military veteran with a below-the-knee amputation of his right leg was suffering from amputation site hyperhidrosis, which was impeding his ability to comfortably wear a prosthesis. Prior to presenting to our clinic, the patient received one treatment of BTX-A injections to his amputation stump while under general anesthesia for surgical repair of trauma-related injuries. In our dermatology clinic, we repeated the procedure using topical lidocaine-prilocaine (30 gm total) for local anesthesia. This provided effective relief of hyperhidrosis for 6 months, but the procedure was very painful (9/10 intensity). We repeated the same procedure 6 months later, using ice in addition to topical lidocaine-prilocaine (30 gm) for local anesthesia; this resulted in reduced pain (3/10 intensity) for the patient. CONCLUSIONS: We suggest using ice in combination with a topical anesthetic as an effective method for pain control that avoids general anesthesia in treating amputation-associated hyperhidrosis.


Asunto(s)
Inhibidores de la Liberación de Acetilcolina/uso terapéutico , Anestesia Local/métodos , Anestésicos Locales/uso terapéutico , Toxinas Botulínicas Tipo A/uso terapéutico , Crioterapia/métodos , Hiperhidrosis/tratamiento farmacológico , Dermatosis de la Pierna/tratamiento farmacológico , Administración Cutánea , Muñones de Amputación , Amputación Traumática/complicaciones , Humanos , Hiperhidrosis/etiología , Inyecciones Intradérmicas , Lidocaína/uso terapéutico , Masculino , Prilocaína/uso terapéutico , Veteranos , Adulto Joven
20.
Asian J Urol ; 3(2): 75-81, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29264168

RESUMEN

OBJECTIVE: To examine the prognostic value of tumor major histocompatibility complex I (MHCI) expression on survival and recurrence in patients with clear cell renal cell carcinoma (RCC). METHODS: Fifty-three patients that underwent nephrectomy at our institution for clear cell RCC (T1-T3) with ≥4 years of follow-up were queried from our nephrectomy database. Immunohistochemical staining for MHCI was performed on tumor specimens and MHCI expression was quantified with an automated image analysis technique. Patients were divided into high and low MHCI expression groups in order to study the relationship between MHCI expression and prognosis using the Kaplan-Meier method and log-rank test. RESULTS: Overall survival and recurrence free survival were increased in the high MHCI expression group compared to the low MHCI expression group (log-rank, p = 0.036 and p = 0.028, respectively). Patients alive at the end of the study had higher MHCI expression (mean positivity score 0.82) than those that died of disease (mean positivity score 0.76, t test, p = 0.030). Patients that did not develop recurrence during the study period had higher MHCI expression (mean positivity score 0.83) than those that did develop recurrence (mean positivity score 0.78), but this difference was not significant (t test, p = 0.079). CONCLUSION: Our data demonstrate that high MHCI expression confers improved overall and recurrence free survival in patients with clear cell RCC and could serve as an important prognostic tool in identifying high-risk patients.

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