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1.
JAMA Dermatol ; 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38717752

RESUMEN

This case series describes a constellation of novel adverse reactions in 3 of 9 patients with uveal melanoma receiving treatment targeting activity of the Brahma-associated factor chromatin remodeling complex.

3.
Radiother Oncol ; 188: 109892, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37659660

RESUMEN

BACKGROUND AND PURPOSE: Clinically localized Merkel cell carcinoma (MCC) has been associated with high rates of disease relapse. This study examines how primary tumor anatomic site drives patterns of care and outcomes in a large cohort treated in the contemporary era. MATERIALS AND METHODS: Patterns of care and associated outcomes were evaluated for clinically Stage I-II MCC patients treated at our institution with adjuvant radiation therapy (RT) to the primary site and/or regional nodal basin as a component of their curative intent therapy between 2014-2021. RESULTS: Of 80 patients who met inclusion criteria, the primary tumor anatomic site was head and neck (HN) for 42 (53%) and non-head and neck (NHN) for 38 (47%). Primary tumor risk factors were similar between cohorts. Fewer patients with HN tumors had wide local excision (WLE; HN-81% vs. NHN-100% p < 0.01). Of those undergoing WLE, patients with HN tumors received higher dose adjuvant RT (>50 Gy: HN-70% vs. NHN-8%; p < 0.01). Patients with HN tumors were less likely to undergo sentinel lymph node biopsy (HN-62%vs. NHN-100%; p < 0.01) and more likely to have elective nodal RT (HN-48% vs. NHN-0%). Despite varying management strategies, there was no significant difference in local recurrence-free survival (3-yr LRFS HN-94% vs. NHN-94%; p = 0.97), nodal recurrence-free survival (3-yr NRFS HN-89% vs. NHN-85%; p = 0.71) or overall recurrence-free survival (3-yr RFS 73% HN vs. 80% NHN; p = 0.44). CONCLUSIONS: Among patients with primary MCC who had RT as a component of their initial treatment strategy, anatomically-driven heterogeneous treatment approaches were associated with equally excellent locoregional disease control.

4.
Indian J Dermatol ; 68(1): 122, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37151244

RESUMEN

The use of oral gauze is a quick, cheap, and effective method of preventing bleeding into the patient's mouth during dermatologic surgery. We recommend this technique combined with appropriate positioning for lesions in the perioral and perinasal regions. Similar approaches may be applied for the prevention of bleeding into the ear canal during facial/periauricular surgery.

5.
J Cutan Pathol ; 50(7): 661-673, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37150813

RESUMEN

BACKGROUND: Immune checkpoint inhibitor (ICI)-based cancer therapies cause a variety of cutaneous immune-related adverse events (irAEs) including immunobullous skin eruptions like bullous pemphigoid (BP). However, little is known about the underlying immunopathogenic drivers of these reactions, and understanding the unique gene expression profile and immune composition of BP-irAE remains a critical knowledge gap in the field of oncodermatology/oncodermatopathology. METHODS: BP-irAE (n = 8) and de novo BP control (n = 8) biopsy samples were subjected to gene expression profiling using the NanoString® Technologies nCounter PanCancer Immune Profiling Panel. Multiplex immunofluorescence (mIF) studies using markers for T-cells (CD3 and CD8), T helper 1 (TH 1) cells (Tbet), TH 2 cells (Gata3), TH 17 cells (RORγT), and regulatory T-cells (Tregs; FoxP3) were further evaluated using InForm® image analysis. RESULTS: Compared with de novo BP controls, BP-irAE samples exhibited upregulation of 30 mRNA transcripts (p < 0.025), including toll-like receptor 4 (TLR4) and genes associated with complement activation, and downregulation of 89 mRNA transcripts (p < 0.025), including genes associated with TH 2, TH 17, and B-cell immune response. BP-irAE demonstrated a greater density of Tbet+ (TH 1) cells in the dermis (p = 0.004) and fewer Tregs in the blister floor (p = 0.028) when compared with that of de novo control BP samples. CONCLUSIONS: BP-irAE exhibited activation of the TLR4/complement-driven classical innate immune response pathway, with dermal TH 1 immune cell polarization and decreased Tregs in the blister floor. TLR/complement signaling may underlie the immunopathogenesis of BP-irAE.


Asunto(s)
Penfigoide Ampolloso , Humanos , Vesícula/metabolismo , Proteínas del Sistema Complemento , Técnica del Anticuerpo Fluorescente , Perfilación de la Expresión Génica , Inmunidad Innata , Penfigoide Ampolloso/patología , ARN Mensajero , Receptor Toll-Like 4/metabolismo , Regulación hacia Arriba
6.
Clin Dermatol ; 41(1): 215-218, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36509341

RESUMEN

With changes to interview format and away rotations, the COVID-19 pandemic has reshaped the residency application process. In this retrospective cohort study of data from the nationwide Texas Seeking Transparency in Applications to Residency (STAR) survey, we sought to understand how the pandemic has affected applicants in the 2021 dermatology Match. We compared applicants in the post-COVID-19 Match year (2021) with those in pre-COVID-19 Match years (2018-2020) regarding match rates, interview costs, residency geographic connections, and number of interviews attended. A total of 439 dermatology applicants who completed the Texas STAR survey were included. There was no difference in percentage of applicants with a geographic connection to their matched program (43.88% vs 47.20%). Compared with prior cycles, applicants in the 2021 Match had a higher percentage of interview offers (96% vs 90%, P < .0001), and more applicants attended 16 or more interviews (P = .0489). Applicants in the 2021 Match reported an average savings of $5,000 compared with prior cycles. Virtual interviews offer savings for applicants but may encourage interview hoarding. Though applicants did not perform away rotations, there was no increase in geographic connection for matched applicants. Stakeholders should consider these data when evaluating the pros and cons of virtual interviewing postpandemic.


Asunto(s)
COVID-19 , Dermatología , Internado y Residencia , Humanos , COVID-19/epidemiología , Pandemias , Estudios Retrospectivos , Texas
7.
J Cutan Pathol ; 50(1): 72-95, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36069496

RESUMEN

BACKGROUND: Since their first approval 25 years ago, monoclonal antibodies (mAbs) have become important targeted cancer therapeutics. However, dermatologic toxicities associated with non-immune checkpoint inhibitor (non-ICI) mAbs may complicate the course of cancer treatment. Data on the incidence and types of these reactions are limited. METHODS: A comprehensive review was conducted on dermatologic toxicities associated with different classes of non-ICI mAbs approved for treatment of solid tumors and hematologic malignancies. The review included prospective Phase 1, 2, and 3 clinical trials; retrospective literature reviews; systematic reviews/meta-analyses; and case series/reports. RESULTS: Dermatologic toxicities were associated with several types of non-ICI mAbs. Inflammatory reactions were the most common dermatologic toxicities, manifesting as maculopapular, urticarial, papulopustular/acneiform, and lichenoid/interface cutaneous adverse events (cAEs) with non-ICI mAbs. Immunobullous reactions were rare and a subset of non-ICI mAbs were associated with the development of vitiligo cAEs. CONCLUSION: Dermatologic toxicities of non-ICI mAbs are diverse and mostly limited to inflammatory reactions. Awareness of the spectrum of the histopathologic patterns of cAE from non-ICI mAbs therapy is critical in the era of oncodermatology and oncodermatopathology.


Asunto(s)
Antineoplásicos Inmunológicos , Erupciones por Medicamentos , Neoplasias , Humanos , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados/efectos adversos , Estudios Retrospectivos , Estudios Prospectivos , Antineoplásicos Inmunológicos/uso terapéutico , Erupciones por Medicamentos/patología , Neoplasias/tratamiento farmacológico
8.
Skinmed ; 20(3): 213-214, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35779028

RESUMEN

A 65-year-old man with diabetes, end-stage renal disease on hemodialysis, coronary artery disease, and a prosthetic aortic valve. He presented to the emergency department with hypothermia (96.6°F), several weeks of anorexia and chills, and bilateral lower extremity tissue necrosis with erythema and edema (Figure 1A). He had a peripherally inserted central catheter (PICC) line 8 weeks prior placed at another hospital for treatment of cellulitis. Laboratory results revealed anemia, azotemia, and leukocytosis (19,200 WBCs/mm3), and he was admitted for sepsis of unknown etiology. (SKINmed. 2022;20:213-214).


Asunto(s)
Cateterismo Venoso Central , Cateterismo Periférico , Cuervos , Fungemia , Anciano , Animales , Candida , Cateterismo Venoso Central/métodos , Cateterismo Periférico/métodos , Fungemia/complicaciones , Fungemia/diagnóstico , Humanos , Masculino
9.
Clin Exp Dermatol ; 47(11): 1928-1942, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35844072

RESUMEN

The discovery of immune checkpoint inhibition (ICI) sparked a revolution in the era of targeted anticancer therapy. However, although monoclonal antibodies targeting the cytotoxic T-lymphocyte antigen-4 and programmed death-1 axes have improved survival in patients with advanced cancers, these immunotherapies are associated with a wide spectrum of dermatological immune-related adverse events (irAEs), ranging from mild to life-threatening. Several publications have addressed the clinical and histopathological classification of these skin-directed irAEs, their impact on anti-tumour immunity and survival, and the critical role of supportive oncological dermatology in their management. In this paper, we review the current understanding of the mechanistic drivers of immune-related skin toxicities with a focus on inflammatory, immunobullous and melanocyte/pigment-related reactions. We detail the specific immune-based mechanisms that may underlie different cutaneous reactions. We also discuss potential mechanisms as they relate to extracutaneous irAEs and the lessons learned from these, the potential overlap with cutaneous irAEs, techniques to study differences in immune-related vs. de novo skin reactions, and how treatment of these AEs impacts cancer treatment, patient quality of life and overall survival. An improved understanding of the mechanistic basis of cutaneous irAEs will allow clinicians to develop and use blood-based biomarkers that could help ultimately predict onset and/or severity of these irAEs, and to implement rational mechanistic-based treatment strategies that are targeted to the irAEs while potentially avoiding reducing the anti-tumour effect of ICIs.


Asunto(s)
Antineoplásicos Inmunológicos , Neoplasias , Humanos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Calidad de Vida , Antineoplásicos Inmunológicos/efectos adversos , Neoplasias/tratamiento farmacológico , Anticuerpos Monoclonales/efectos adversos
10.
Clin Pharmacol Ther ; 111(1): 252-262, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34564842

RESUMEN

Oral alkalization with sodium bicarbonate (NaHCO3 ) or citrate is prescribed for conditions ranging from metabolic acidosis to nephrolithiasis. Although most nephrologists/urologists use this method routinely, extracellular volume (ECV) increase is the main feared adverse event reported for NaHCO3 . Thus far, no trial has specifically studied this issue in a real-world setting. AlcalUN (NCT03035812) is a multicentric, prospective, open-label cohort study with nationwide (France) enrollment in 18 (public and private) nephrology/urology units. Participants were adult outpatients requiring chronic (>1 month) oral alkalization by either NaHCO3 -containing or no-NaHCO3 -containing agents. The ECV increase (primary outcome) was judged based on body weight increase (ΔBW), blood pressure increase (ΔBP), and/or new-onset edema at the first follow-up visit (V1). From February 2017 to February 2020, 156 patients were enrolled. After a median 106 days of treatment, 91 (72%) patients reached the primary outcome. They had lower systolic (135 (125, 141) vs. 141 (130, 150), P = 0.02) and diastolic (77 (67, 85) vs. 85 (73, 90), P = 0.03) BP values, a higher plasma chloride (106.0 (105.0, 109.0) vs. 105.0 (102.0, 107.0), P = 0.02) at baseline, and a less frequent history of nephrolithiasis (32 vs. 56%, P = 0.02). Patients experienced mainly slight ΔBP (< 10 mmHg). The primary outcome was not associated (P = 0.79) with the study treatment (129 received NaHCO3 and 27 received citrate). We subsequently developed three different models of propensity score matching; each confirmed our results. Chronic oral alkalization with NaHCO3 is no longer associated with an ECV increase compared to citrate in real-life settings.


Asunto(s)
Antiácidos/efectos adversos , Espacio Extracelular/química , Espacio Extracelular/efectos de los fármacos , Bicarbonato de Sodio/efectos adversos , Anciano , Presión Sanguínea/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Francia , Humanos , Masculino , Persona de Mediana Edad , Citrato de Potasio/efectos adversos , Puntaje de Propensión , Estudios Prospectivos
11.
Endocr Connect ; 11(1)2022 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-34939939

RESUMEN

Context: Recent guidelines have provided recommendations for the care of patients with chronic hypoparathyroidism. Very little is known about actual physicians' practices or their adherence to such guidelines. Objective: To describe the physicians' practice patterns and their compliance with international guidelines. Design: The cohort studies included were Épi-Hypo (118 physicians and 107 patients, from September 2016 to December 2019) and ePatients (110 patients, November 2019). Methods: Internet-based cohorts involving all settings at a nationwide level (France). Participants were (i) physicians treating patients with chronic hypoparathyroidism and patients with chronic hypoparathyroidism either participating in the (ii) Épi-Hypo study (Épi-Hypo 2019 patients), or (iii) Hypoparathyroidism France, the national representative association (ePatients). Results: The physicians' specialties were mainly endocrinology (61%), nephrology (28%), family medicine (2.5%), pediatrics (2.5%), rheumatology (2%), or miscellaneous (4%) and 45% were practicing in public universities. The median number of pharmaceutical drug classes prescribed was three per patient. The combination of active vitamin D and calcium salt was given to 59 and 58% of ePatients and Épi-Hypo 2019 patients, respectively. Eighty-five percent of ePatients and 87% of physicians reported monitoring plasma calcium concentrations at a steady state at least twice a year. In 32 and 26% of cases, respectively, ePatients and physicians reported being fully in accordance with international guidelines that recommend targeting symptoms, plasma calcium and phosphate values, and urine calcium excretion. Conclusions: The care of patients with chronic hypoparathyroidism involves physicians with very different practices, so guidelines should include and target other specialists as well as endocrinologists. Full adherence to the guidelines is low in France.

12.
J Cutan Pathol ; 49(5): 472-481, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34888886

RESUMEN

Breakthrough targeted therapies have produced significant improvements in survival for cancer patients, but have a propensity to cause cutaneous immune-related adverse events (irAEs). Psoriasiform irAEs, representing about 4% of dermatologic toxicities associated with immune checkpoint inhibitor (ICI) therapy, are usually mild, occur in older patients and present as an exacerbation of existing psoriasis after several doses of ICI therapy. We report a case of a 58-year-old woman with metastatic esophageal adenocarcinoma and no prior history of psoriasis who developed a pustular psoriasiform irAE, beginning 3 days after initiation of nivolumab and progressing to confluent erythroderma with pustules over 2 weeks despite topical steroid use. She had concurrent acrodermatitis enteropathica, clinically diagnosed and confirmed with a low serum zinc level, that improved with supplementation. Her psoriasiform irAE was refractory to systemic steroids and acitretin, prompting discontinuation of nivolumab and treatment with ustekinumab and concomitant slow taper of acitretin and prednisone. Pustular psoriasiform irAE is a rare but severe dermatologic toxicity resulting from ICI therapy. Given the diverse morphologic types of cutaneous irAEs that can occur during ICI therapy, a clinical and histopathologic examination of dermatologic toxicities is critical to identify patients who may benefit from biologic therapy.


Asunto(s)
Adenocarcinoma , Psoriasis , Acitretina , Adenocarcinoma/tratamiento farmacológico , Anciano , Neoplasias Esofágicas , Femenino , Humanos , Persona de Mediana Edad , Nivolumab/efectos adversos , Psoriasis/inducido químicamente , Psoriasis/tratamiento farmacológico
13.
J Cutan Pathol ; 49(1): 61-81, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34622477

RESUMEN

BACKGROUND: Advances in molecular biology and genetics have contributed to breakthrough treatments directed at specific pathways associated with the development of cancer. Small-molecule inhibitors (Nibs) aimed at a variety of cellular pathways have been efficacious; however, they are associated with significant dermatologic toxicities. METHODS: We conducted a comprehensive review of dermatologic toxicities associated with Nibs categorized into the following five groups: (a) mitogen-activated protein kinase; (b) growth factor/multi-tyrosine kinase; (c) cell division/DNA repair; (d) signaling associated with myeloproliferative neoplasms; and (e) other signaling pathways. Prospective phase I, II, or III clinical trials, retrospective literature reviews, systematic reviews/meta-analyses, and case reviews/reports were included for analysis. RESULTS: Dermatologic toxicities reviewed were associated with every class of Nibs and ranged from mild to severe or life-threatening adverse skin reactions. Inflammatory reactions manifesting as maculopapular, papulopustular/acneiform, and eczematous lesions were frequent types of dermatologic toxicities seen with Nibs. Squamous cell carcinoma with keratoacanthoma-like features was associated with a subset of Nibs. Substantial overlap in dermatologic toxicities was found between Nibs. CONCLUSIONS: Dermatologic toxicities from Nibs are diverse and may overlap between classes of Nibs. Recognition of the various types of toxicities from Nibs is critical for patient care in the era of "oncodermatology/dermatopathology."


Asunto(s)
Antineoplásicos , Erupciones por Medicamentos , Inhibidores Enzimáticos , Neoplasias , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Erupciones por Medicamentos/metabolismo , Erupciones por Medicamentos/patología , Inhibidores Enzimáticos/efectos adversos , Inhibidores Enzimáticos/uso terapéutico , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/patología
14.
Sci Adv ; 7(14)2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33811077

RESUMEN

Epigenetic effectors "read" marks "written" on chromatin to regulate function and fidelity of the genome. Here, we show that this coordinated read-write activity of the epigenetic machinery extends to the cytoskeleton, with PBRM1 in the PBAF chromatin remodeling complex reading microtubule methyl marks written by the SETD2 histone methyltransferase. PBRM1 binds SETD2 methyl marks via BAH domains, recruiting PBAF components to the mitotic spindle. This read-write activity was required for normal mitosis: Loss of SETD2 methylation or pathogenic BAH domain mutations disrupt PBRM1 microtubule binding and PBAF recruitment and cause genomic instability. These data reveal PBRM1 functions beyond chromatin remodeling with domains that allow it to integrate chromatin and cytoskeletal activity via its acetyl-binding BD and methyl-binding BAH domains, respectively. Conserved coordinated activity of the epigenetic machinery on the cytoskeleton opens a previously unknown window into how chromatin remodeler defects can drive disease via both epigenetic and cytoskeletal dysfunction.


Asunto(s)
Microtúbulos , Lectura , Cromatina/metabolismo , Ensamble y Desensamble de Cromatina , Citoesqueleto/metabolismo , Microtúbulos/metabolismo
15.
Biochem Biophys Res Commun ; 558: 202-208, 2021 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-33036756

RESUMEN

The process of autophagy is dysregulated in many cancers including clear cell renal cell carcinoma (ccRCC). Autophagy involves the coordination of numerous autophagy-related (ATG) genes, as well as processes involving the actin cytoskeleton. The histone methyltransferase SETD2, frequently inactivated in ccRCC, has recently been shown to also methylate cytoskeletal proteins, which in the case of actin lysine 68 trimethylation (ActK68me3) regulates actin polymerization dynamics. Here we show that cells lacking SETD2 exhibit autophagy defects, as well as decreased interaction of the actin nucleation promoting factor WHAMM with its target actin, which is required for initiation of autophagy. Interestingly, the WHAMM actin binding deficit could be rescued with pharmacologic induction of actin polymerization in SETD2-null cells using Jasplakinolide. These data indicate that the decreased interaction between WHAMM and its target actin in SETD2-null cells was secondary to altered actin dynamics rather than loss of the SETD2 ActK68me3 mark itself, and underscores the importance of the functional defect in actin polymerization in SETD2-null cells exhibiting autophagy defects.


Asunto(s)
Actinas/metabolismo , Carcinoma de Células Renales/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Neoplasias Renales/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Autofagia/genética , Autofagia/fisiología , Proteínas Relacionadas con la Autofagia/genética , Proteínas Relacionadas con la Autofagia/metabolismo , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Línea Celular , Línea Celular Tumoral , Regulación hacia Abajo , Técnicas de Inactivación de Genes , N-Metiltransferasa de Histona-Lisina/deficiencia , N-Metiltransferasa de Histona-Lisina/genética , Humanos , Neoplasias Renales/genética , Neoplasias Renales/patología
16.
Sci Adv ; 6(40)2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33008892

RESUMEN

The methyltransferase SET domain-containing 2 (SETD2) was originally identified as Huntingtin (HTT) yeast partner B. However, a SETD2 function associated with the HTT scaffolding protein has not been elucidated, and no linkage between HTT and methylation has yet been uncovered. Here, we show that SETD2 is an actin methyltransferase that trimethylates lysine-68 (ActK68me3) in cells via its interaction with HTT and the actin-binding adapter HIP1R. ActK68me3 localizes primarily to the insoluble F-actin cytoskeleton in cells and regulates actin polymerization/depolymerization dynamics. Disruption of the SETD2-HTT-HIP1R axis inhibits actin methylation, causes defects in actin polymerization, and impairs cell migration. Together, these data identify SETD2 as a previously unknown HTT effector regulating methylation and polymerization of actin filaments and provide new avenues for understanding how defects in SETD2 and HTT drive disease via aberrant cytoskeletal methylation.


Asunto(s)
Actinas , Proteínas de Unión al GTP/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Lisina , Actinas/metabolismo , Citoesqueleto/metabolismo , Lisina/metabolismo , Metilación , Procesamiento Proteico-Postraduccional
17.
Cancer Cell ; 37(5): 720-734.e13, 2020 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-32359397

RESUMEN

Renal medullary carcinoma (RMC) is a highly lethal malignancy that mainly afflicts young individuals of African descent and is resistant to all targeted agents used to treat other renal cell carcinomas. Comprehensive genomic and transcriptomic profiling of untreated primary RMC tissues was performed to elucidate the molecular landscape of these tumors. We found that RMC was characterized by high replication stress and an abundance of focal copy-number alterations associated with activation of the stimulator of the cyclic GMP-AMP synthase interferon genes (cGAS-STING) innate immune pathway. Replication stress conferred a therapeutic vulnerability to drugs targeting DNA-damage repair pathways. Elucidation of these previously unknown RMC hallmarks paves the way to new clinical trials for this rare but highly lethal malignancy.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma Medular/patología , Carcinoma de Células Renales/patología , Aberraciones Cromosómicas , Replicación del ADN , Neoplasias Renales/patología , Proteína SMARCB1/metabolismo , Adulto , Animales , Apoptosis , Biomarcadores de Tumor/genética , Carcinoma Medular/genética , Carcinoma Medular/inmunología , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/inmunología , Proliferación Celular , Estudios de Cohortes , Variaciones en el Número de Copia de ADN , Femenino , Regulación Neoplásica de la Expresión Génica , Genómica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias Renales/genética , Neoplasias Renales/inmunología , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Ratones Desnudos , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Pronóstico , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteína SMARCB1/genética , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Eukaryot Cell ; 12(12): 1629-40, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24123269

RESUMEN

Candida species exhibit a variety of ploidy states and modes of sexual reproduction. Most species possess the requisite genes for sexual reproduction, recombination, and meiosis, yet only a few have been reported to undergo a complete sexual cycle including mating and sporulation. Candida albicans, the most studied Candida species and a prevalent human fungal pathogen, completes its sexual cycle via a parasexual process of concerted chromosome loss rather than a conventional meiosis. In this study, we examine ploidy changes in Candida tropicalis, a closely related species to C. albicans that was recently revealed to undergo sexual mating. C. tropicalis diploid cells mate to form tetraploid cells, and we show that these can be induced to undergo chromosome loss to regenerate diploid forms by growth on sorbose medium. The diploid products are themselves mating competent, thereby establishing a parasexual cycle in this species for the first time. Extended incubation (>120 generations) of C. tropicalis tetraploid cells under rich culture conditions also resulted in instability of the tetraploid form and a gradual reduction in ploidy back to the diploid state. The fitness levels of C. tropicalis diploid and tetraploid cells were compared, and diploid cells exhibited increased fitness relative to tetraploid cells in vitro, despite diploid and tetraploid cells having similar doubling times. Collectively, these experiments demonstrate distinct pathways by which a parasexual cycle can occur in C. tropicalis and indicate that nonmeiotic mechanisms drive ploidy changes in this prevalent human pathogen.


Asunto(s)
Candida tropicalis/citología , Candida tropicalis/genética , Ploidias , Citometría de Flujo , Genes del Tipo Sexual de los Hongos , Reproducción
19.
Mol Reprod Dev ; 80(8): 590-609, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23450642

RESUMEN

Formation of the germline in an embryo marks a fresh round of reproductive potential, yet the developmental stage and location within the embryo where the primordial germ cells (PGCs) form differs wildly among species. In most animals, the germline is formed either by an inherited mechanism, in which maternal provisions within the oocyte drive localized germ-cell fate once acquired in the embryo, or an inductive mechanism that involves signaling between cells that directs germ-cell fate. The inherited mechanism has been widely studied in model organisms such as Drosophila melanogaster, Caenorhabditis elegans, Xenopus laevis, and Danio rerio. Given the rapid generation time and the effective adaptation for laboratory research of these organisms, it is not coincidental that research on these organisms has led the field in elucidating mechanisms for germline specification. The inductive mechanism, however, is less well understood and is studied primarily in the mouse (Mus musculus). In this review, we compare and contrast these two fundamental mechanisms for germline determination, beginning with the key molecular determinants that play a role in the formation of germ cells across all animal taxa. We next explore the current understanding of the inductive mechanism of germ-cell determination in mice, and evaluate the hypotheses for selective pressures on these contrasting mechanisms. We then discuss the hypothesis that the transition between these determination mechanisms, which has happened many times in phylogeny, is more of a continuum than a binary change. Finally, we propose an analogy between germline determination and sex determination in vertebrates-two of the milestones of reproduction and development-in which animals use contrasting strategies to activate similar pathways.


Asunto(s)
Diferenciación Celular/genética , Gametogénesis/fisiología , Células Germinativas/metabolismo , Procesos de Determinación del Sexo/genética , Animales , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Caenorhabditis elegans/genética , ARN Helicasas DEAD-box/genética , ARN Helicasas DEAD-box/metabolismo , Proteínas de Unión al ADN , Drosophila melanogaster/genética , Gametogénesis/genética , Regulación del Desarrollo de la Expresión Génica , Células Germinativas/citología , Ratones , Factor 1 de Unión al Dominio 1 de Regulación Positiva , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Transducción de Señal/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Xenopus laevis/genética
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