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1.
Dermatol Ther (Heidelb) ; 12(3): 643-654, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35122614

RESUMEN

INTRODUCTION: Treatment of early-stage mycosis fungoides (MF) requires safe, skin-directed therapies. Medication side effects can lead to underutilization of effective therapies. The objective of this study was to assess the use of topical triamcinolone 0.1% ointment as a means of reducing contact dermatitis associated with topical mechlorethamine/chlormethine gel for the treatment of MF. METHODS: This prospective, randomized, open-label study evaluated 28 adults with mycosis fungoides who were eligible for treatment with topical mechlorethamine/chlormethine gel from December 17, 2017 to December 23, 2020. Patients were treated for 4 months with clinical follow-up through 12 months. Patients had half of their lesions also treated with topical triamcinolone 0.1% ointment (while the other half were treated with mechlorethamine/chlormethine alone). The study was self-controlled with separate lesions in the same patient receiving each treatment arm. Treatment arms were determined by the flip of a coin. RESULTS: Twenty-eight patients enrolled (17 men (61%) and 11 women (39%)). Demographics included 25 White, 2 African Americans, and 1 Asian patient. Twenty-five completed the 12-month follow-up. Triamcinolone 0.1% ointment led to increased tolerability of mechlorethamine/chlormethine gel but did not change the efficacy of mechlorethamine/chlormethine. There was a statistically significant 50% decrease in dermatitis (SCORD score) at month 2 in the triamcinolone-treated arm. CONCLUSIONS: Topical triamcinolone ointment is a helpful adjuvant therapy when treating patients with topical mechlorethamine/chlormethine gel. It diminishes inflammation and does not reduce efficacy. The peak incidence of dermatitis in the study occurred in the second and third months. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT03380026.

2.
NPJ Breast Cancer ; 7(1): 81, 2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-34172750

RESUMEN

STING signaling in cancer is a crucial component of response to immunotherapy and other anti-cancer treatments. Currently, there is no robust method of measuring STING activation in cancer. Here, we describe an immunohistochemistry-based assay with digital pathology assessment of STING in tumor cells. Using this novel approach in estrogen receptor-positive (ER+) and ER- breast cancer, we identify perinuclear-localized expression of STING (pnSTING) in ER+ cases as an independent predictor of good prognosis, associated with immune cell infiltration and upregulation of immune checkpoints. Tumors with low pnSTING are immunosuppressed with increased infiltration of "M2"-polarized macrophages. In ER- disease, pnSTING does not appear to have a significant prognostic role with STING uncoupled from interferon responses. Importantly, a gene signature defining low pnSTING expression is predictive of poor prognosis in independent ER+ datasets. Low pnSTING is associated with chromosomal instability, MYC amplification and mTOR signaling, suggesting novel therapeutic approaches for this subgroup.

4.
Histopathology ; 77(4): 646-658, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32617996

RESUMEN

AIMS: Ki67 proliferative index (PI) is essential for grading gastroenteric and pancreatic neuroendocrine tumours (GEP NETs). Analytical and preanalytical variables can affect Ki67 PI. In contrast to counting methodology, until now little attention has focused on the question of clone equivalence and the effect of hot-spot size on Ki67 PI in GEP NETs. Using manual counting and image analysis, this study compared the Ki67 PI achieved using MM1, K2 and 30-9 to MIB1, a clone which has been validated for, and is referenced in, guidelines relating to assessment of Ki67 PI in GEP NETs. METHODS AND RESULTS: Forty-two pancreatic NETs were each immunohistochemically stained for the anti-Ki67 clones MIB1, MM1, K2 and 30-9. Ki67 PI was calculated manually and by image analysis, the latter using three different hot-spot sizes. In manual comparisons using single hot-spot high-power fields, non-MIB1 clones overestimated Ki67 PI compared to MIB1, resulting in grading discordances. Image analysis shows good agreement with manual Ki67 PI but a tendency to overestimate absolute Ki67 PI. Increasing the size of tumour hot-spot from 500 to 2000 cells resulted in a decrease in Ki67 PI. CONCLUSION: Different anti-Ki67 clones do not produce equivalent PIs in GEP NETs, and clone selection may therefore affect patient care. Increasing the hot-spot size decreases the Ki67 PI. Greater standardisation in terms of antibody clone selection and hot-spot size is required for grading GEP NETs. Image analysis is an effective tool for assisting Ki67 assessment and allows easier standardisation of the size of the tumour hot-spot.


Asunto(s)
Biomarcadores de Tumor/análisis , Interpretación de Imagen Asistida por Computador/métodos , Neoplasias Intestinales/patología , Índice Mitótico/métodos , Clasificación del Tumor/métodos , Tumores Neuroendocrinos/patología , Neoplasias Pancreáticas/patología , Neoplasias Gástricas/patología , Anticuerpos Antinucleares , Anticuerpos Monoclonales , Humanos , Inmunohistoquímica/métodos , Inmunohistoquímica/normas , Antígeno Ki-67/análisis , Índice Mitótico/normas , Clasificación del Tumor/normas
5.
J Oncol ; 2019: 4325105, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31320901

RESUMEN

Historically the development of anticancer treatments has been focused on their effect on tumor cells alone. However, newer treatments have shifted attention to targets on immune cells, resulting in dramatic responses. The effect of DNA repair deficiency on the microenvironment remains an area of key interest. Moreover, established therapies such as DNA damaging treatments such as chemotherapy and PARP inhibitors further modify the tumor microenvironment. Here we describe DNA repair pathways in breast cancer and activation of innate immune pathways in DNA repair deficiency, in particular, the STING (STimulator of INterferon Genes) pathway. Breast tumors with DNA repair deficiency are associated with upregulation of immune checkpoints including PD-L1 (Programmed Death Ligand-1) and may represent a target population for single agent or combination immunotherapy treatment.

6.
Am J Clin Dermatol ; 19(1): 119-126, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28801732

RESUMEN

BACKGROUND: Alopecia areata (AA) is an autoimmune disease characterized by non-scarring alopecia with T-cell infiltration at the affected hair follicle. OBJECTIVE: Our aim was to study the potential link between hepatitis B virus (HBV) antigen exposure and AA. METHODS: Two pediatric patients with AA following hepatitis B vaccination were identified in a general dermatology clinic. A bioinformatics analysis and an electronic medical record (EMR) database query were performed at the University of Rochester Medical Center to identify patients with AA, coexisting viral infections, vaccinations, or interferon (IFN) therapy in order to determine if the presence of AA and these conditions was higher than in AA patients without these associated conditions or therapy. RESULTS: An increased frequency of AA among those who received the HBV surface protein antigen [odds ratio (OR) 2.7, p < 0.0001] was identified, and an independent analysis revealed an increased frequency of AA in those receiving IFN-ß treatment (OR 8.1, p < 0.05). One potential antigenic target identified was SLC45A2, a melanosomal transport protein important in skin and hair pigmentation. The longest potential vaccine peptide fragment match (8-mer) was to a segment of natural killer (NK) cell inhibitory receptors, KIR3DL2 and KIR3DL1. Predictive modeling of major histocompatibility complex (MHC)-peptide binding demonstrated potential binding of this peptide to MHC relevant to AA. LIMITATIONS: The results will need to be verified in additional patient databases allowing analysis of temporal relationships, and with molecular experiments of the identified antigens. CONCLUSIONS: Our data confirm associations between viral infection and IFN treatment with AA. It establishes that the hepatitis B surface protein antigen has shared epitopes with human killer immunoglobulin-like receptors.


Asunto(s)
Alopecia Areata/inmunología , Enfermedades Autoinmunes/inmunología , Vacunas contra Hepatitis B/inmunología , Virus de la Hepatitis B/inmunología , Inmunosupresores/uso terapéutico , Alopecia Areata/tratamiento farmacológico , Antígenos Virales/inmunología , Enfermedades Autoinmunes/tratamiento farmacológico , Preescolar , Femenino , Folículo Piloso/inmunología , Humanos , Lactante
7.
Carcinogenesis ; 39(3): 418-428, 2018 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-29186361

RESUMEN

Squamous cell carcinoma (SCC) of the skin is a keratinocyte malignancy characterized by tumors presenting on sun-exposed areas with surgery being the mainstay treatment. Despite advances in targeted therapy in other skin cancers, such as basal cell carcinoma and melanoma, there have been no such advances in the treatment of SCC. This is partly due to an incomplete knowledge of the pathogenesis of SCC. We have recently identified a protein kinase C-associated kinase (PKK) as a potential tumor suppressor in SCC. We now describe a novel conditional PKK knockout mouse model, which demonstrates that PKK deficiency promotes SCC formation during chemically induced tumorigenesis. Our results further support that PKK functions as a tumor suppressor in skin keratinocytes and is important in the pathogenesis of SCC of the skin. We further define the interactions of keratinocyte PKK with TP63 and NF-κB signaling, highlighting the importance of this protein as a tumor suppressor in SCC development.


Asunto(s)
Carcinoma de Células Escamosas/genética , Transformación Celular Neoplásica/genética , Queratinocitos/patología , Proteínas Serina-Treonina Quinasas/genética , Neoplasias Cutáneas/genética , 9,10-Dimetil-1,2-benzantraceno/toxicidad , Animales , Carcinógenos/toxicidad , Carcinoma de Células Escamosas/inducido químicamente , Carcinoma de Células Escamosas/patología , Genes Supresores de Tumor , Humanos , Queratinocitos/efectos de los fármacos , Ratones , Ratones Noqueados , Piridinas/toxicidad , Transducción de Señal/fisiología , Neoplasias Cutáneas/inducido químicamente , Neoplasias Cutáneas/patología
8.
Brain Behav Immun ; 68: 238-247, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29080684

RESUMEN

Acute stress is a physiological response of an organism to adverse conditions, contributing to survival; however, persistence through time may lead to disease. Indeed, exacerbation of inflammatory conditions such as psoriasis has been reported to follow stressors in susceptible patients. Because chronic stress cannot ethically be elicited in patients under controlled laboratory conditions, we studied genetically modified mice that naturally develop psoriasiform dermatitis, and subjected them to an ethological chronic social contact stress paradigm. Although we found elevated pro-inflammatory neuropeptide production of substance P (SP), calcitonin-gene-related peptide (CGRP) and nerve-growth factor (NGF) mRNA in the dorsal root ganglia (DRG) as well as pro-inflammatory cytokines in response to the social stressor, stress paradoxically prevented the development of the skin lesions. This effect of stress could be reversed by the treatment with glucocorticoid (GC) receptor blockers, suggesting that it was mediated through the upregulation of corticosterone secretion. Extrapolating to humans, the worsening of disease in susceptible patients with psoriasis could be attributed to a defect in the Hypothalamic-Pituitary-Adrenal (HPA) axis with an impaired production of GC during situations of adversity, thus rendering them unable to counteract the pro-inflammatory effects of chronic stressors.


Asunto(s)
Psoriasis/fisiopatología , Estrés Psicológico/metabolismo , Corticoesteroides/metabolismo , Animales , Péptido Relacionado con Gen de Calcitonina , Corticosterona/farmacología , Dermatitis , Modelos Animales de Enfermedad , Ganglios Espinales/metabolismo , Sistema Hipotálamo-Hipofisario/metabolismo , Masculino , Ratones , Ratones Transgénicos , Factor de Crecimiento Nervioso , Neuropéptidos , Sistema Hipófiso-Suprarrenal/metabolismo , Psoriasis/metabolismo , ARN Mensajero , Receptores de Glucocorticoides/metabolismo , Estrés Psicológico/genética , Sustancia P , Activación Transcripcional , Regulación hacia Arriba
10.
J Cutan Pathol ; 43(2): 148-57, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26272477

RESUMEN

Cutaneous squamous cell carcinoma (SCC) with osteoclast-like giant cells (hereafter, osteoclastic cells) is very rare; eight cases have been reported since 2006. Whether the osteoclastic cells represents a reactive or neoplastic change remains a matter of debate. Osteoclastic cells are often observed in the sarcomatous component of cutaneous carcinosarcoma. SCC with osteoclastic cells is a heterogeneous condition that includes SCC with stromal changes containing osteoclastic cells (also known as osteoclast-like giant cell reaction) and carcinosarcoma. In some cases, SCC with an associated osteoclast-like giant cell reaction has been differentiated from carcinosarcoma based on the degree of cytologic atypia in non-epithelial components. We summarized the clinical and histopathologic characteristics of 11 patients of SCC with osteoclastic cells, including our two cases of SCC with an osteoclast-like giant cell reaction and one case of carcinosarcoma. The affected patients were old and more likely to be male (64%). Seven cases (64%) were in the head and neck. Moreover, multiple features of high risk SCC were observed, such as a tumor size greater than 2 cm (56%), moderate or poor differentiation (100%), recurrence (33%) and nodal metastasis (17%) after excision and immunosuppression (27%). Interestingly, half of the previously reported cases of SCC with osteoclastic giant cell reaction had histopathologic findings that were overlapping with those of carcinosarcoma.


Asunto(s)
Carcinoma de Células Escamosas , Carcinosarcoma , Células Gigantes , Neoplasias de Cabeza y Cuello , Osteoclastos , Neoplasias Cutáneas , Anciano , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Carcinosarcoma/metabolismo , Carcinosarcoma/patología , Femenino , Células Gigantes/metabolismo , Células Gigantes/patología , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Osteoclastos/metabolismo , Osteoclastos/patología , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología
11.
Pediatr Dermatol ; 32(5): 628-34, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25557557

RESUMEN

Pruritus is a common complication in patients with epidermolysis bullosa (EB). There is limited published data about the treatments that individuals with EB use for pruritus. The objective of the current study was to determine quantitatively which treatments individuals with EB have used for pruritus and to evaluate the perceived effectiveness of these treatments in pruritus relief. A questionnaire was developed to evaluate the treatments and therapies used for pruritus in patients of all ages and for all types of EB. Questions about bathing products, moisturizers, topical products, oral medications, dressings, and alternative therapies were included. A 5-point Likert scale (-2 = relieves itch a lot, -1 = relieves itch a little, 0 = no change, 1 = increases itch a little, 2 = increases itch a lot) was used to evaluate perceived effectiveness. Patients from seven North American EB centers were invited to participate. Greasy ointments (53.4%), lotions (45.2%), creams (40.4%), and oral hydroxyzine (39.0%) were the most frequently used treatments for pruritus. Treatments that were used frequently and perceived to be the most effective included creams (mean = -1.1), topical prescription corticosteroids (mean = -1.0), oils (mean = -0.9), oral hydroxyzine (mean = -0.9), topical diphenhydramine (mean = -0.9), and vaporizing rub (menthol, camphor, eucalyptus) (mean = -0.9). Systemic opioids (mean = 0.3), adherent bandages (mean = 0.3), and bleach baths (mean = 0.2) slightly increased pruritus. Randomized controlled trials of therapies will be necessary to develop evidence-based recommendations for control of pruritus in individuals with EB.


Asunto(s)
Epidermólisis Ampollosa/complicaciones , Epidermólisis Ampollosa/terapia , Prurito/terapia , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , América del Norte , Aceites/uso terapéutico , Pomadas/uso terapéutico , Prurito/etiología , Crema para la Piel/uso terapéutico , Encuestas y Cuestionarios , Adulto Joven
12.
J Invest Dermatol ; 135(3): 869-876, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25285922

RESUMEN

Non-melanoma skin cancer represents the most common cancer in the United States. Squamous cell carcinoma (SCC) of the skin is a subtype of NMSC that shows a greater potential for invasion and metastasis. The current study identifies the protein kinase C-associated kinase (PKK), which is also known as the receptor-interacting protein kinase 4, as a suppressor of tumor growth in SCC of the skin. We show that expression of PKK is decreased in human SCC of the skin compared with normal skin. Further, suppression of PKK in human keratinocytes leads to increased cell proliferation. The use of RNA interference to reduce PKK expression in keratinocytes leads to an increase in S phase and in proteins that promote cell cycle progression. Consistent with the results obtained from cell culture, there is a marked increased tumorigenesis after PKK knockdown in a xenotransplant model and in soft agar assays. The loss of tumor suppression involves the NF-κB and p63 pathways. NF-κB is inhibited through inhibition of inhibitor of NF-κB kinase function and there is increased nuclear TP63 activity after PKK knockdown. This study opens new avenues both in the discovery of disease pathogenesis and for potential treatments.


Asunto(s)
Carcinogénesis/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Proliferación Celular , Proteínas Serina-Treonina Quinasas/metabolismo , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Animales , Apoptosis/fisiología , Carcinogénesis/patología , Estudios de Casos y Controles , Ciclo Celular , Modelos Animales de Enfermedad , Regulación Neoplásica de la Expresión Génica , Xenoinjertos , Humanos , Queratinocitos/metabolismo , Queratinocitos/patología , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones SCID , FN-kappa B/metabolismo , Proteínas Serina-Treonina Quinasas/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/genética , ARN Interferente Pequeño/farmacología , Transducción de Señal/fisiología , Piel/metabolismo , Piel/patología
13.
Pediatr Dermatol ; 32(1): 53-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25236506

RESUMEN

Qualitative data suggest that pruritus is a burdensome symptom in patients with epidermolysis bullosa (EB), but the prevalence of pruritus in children and adults with EB and factors that contribute to pruritus are unknown. The objective of the current study was to quantitatively identify and to characterize pruritus that EB patients experience using a comprehensive online questionnaire. A questionnaire was developed to evaluate pruritus in all ages and all types of EB. Questions that characterize pruritus were included and factors that aggravate symptoms were investigated. Patients from seven North American EB centers were invited to participate. One hundred forty-six of 216 questionnaires were completed (response rate 68%; 73 male, 73 female; median age 20.0 years). Using a 5-point Likert scale (1 = never, 2 = rarely, 3 = sometimes, 4 = often, 5 = always), itchiness was the most bothersome EB complication (mean 3.3). The average daily frequency of pruritus increased with self-reported EB severity. Pruritus was most frequent at bedtime (mean 3.8) and interfered with sleep. Factors that aggravated pruritus included healing wounds, dry skin, infected wounds, stress, heat, dryness, and humidity. Pruritus is common in individuals with EB and can be bothersome. Future studies will need to investigate the most effective treatments given to individuals with EB for pruritus.


Asunto(s)
Epidermólisis Ampollosa/complicaciones , Prurito/epidemiología , Prurito/etiología , Adolescente , Adulto , Factores de Edad , Niño , Epidermólisis Ampollosa/fisiopatología , Femenino , Humanos , Masculino , Prevalencia , Prurito/fisiopatología , Encuestas y Cuestionarios , Adulto Joven
14.
Pediatrics ; 134(6): e1715-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25404727

RESUMEN

Linear morphea en coup de sabre (ECDS) is a form of localized scleroderma that predominantly affects the pediatric population, with a median age of 10 years at presentation. The existence of neurologic findings in association with ECDS has been well described in the literature. Here we describe 4 patients with ECDS who presented with headaches, which were typical migraines in 3 of the patients. The headaches preceded the onset of cutaneous findings by at least 6 months. Our patients' cases emphasize both the importance of recognizing headaches as a harbinger of ECDS and the necessity of performing thorough cutaneous examination in patients with unexplained headaches or other neurologic disease.


Asunto(s)
Cefalea/etiología , Trastornos Migrañosos/etiología , Esclerodermia Localizada/diagnóstico , Adolescente , Biopsia , Encéfalo/patología , Niño , Diagnóstico Diferencial , Quimioterapia Combinada , Femenino , Cefalea/tratamiento farmacológico , Humanos , Imagen por Resonancia Magnética , Metotrexato/uso terapéutico , Trastornos Migrañosos/tratamiento farmacológico , Prednisona/uso terapéutico , Cuero Cabelludo/patología , Esclerodermia Localizada/etiología , Esclerodermia Localizada/patología
15.
Dermatol Online J ; 21(3)2014 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-25780971

RESUMEN

Penile squamous cell carcinoma is a rare malignancy seen more frequently in developing nations. Metastasis occurs in a predictable manner, with superficial lymph node involvement occurring first, followed by deep lymph node involvement, and then distant spread. Brain, lung, liver, and bone are the typical sites of distant metastasis. We present the unusual case of an 81-year-old man with penile squamous cell carcinoma requiring total penectomy who developed a confluent red to violaceous, indurated suprapubic plaque with satellite papules and bulky inguinal lymphadenopathy. The shield-like clinical presentation and infiltrating strands and cords on histology resembled carcinoma en cuirasse, a rare form of cutaneous metastasis frequently associated with breast cancer but not reported with penile squamous cell carcinoma.


Asunto(s)
Carcinoma de Células Escamosas/secundario , Neoplasias del Pene/patología , Neoplasias Cutáneas/secundario , Anciano de 80 o más Años , Carcinoma de Células Escamosas/cirugía , Humanos , Metástasis Linfática , Masculino , Neoplasias del Pene/cirugía
16.
J Am Acad Dermatol ; 67(4): 760-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22285672

RESUMEN

BACKGROUND: Pruritus can be a distressing and even debilitating symptom for patients with cutaneous T-cell lymphoma (CTCL). To date, few studies have evaluated the pathophysiology of this symptom. Because of this, therapy for pruritus in CTCL has mainly relied on those therapies that target and treat the lymphoma. For patients living with CTCL that relapses or becomes refractory to treatment, and who continue to experience severe itch, this lymphoma-targeted treatment may not be enough to combat their pruritus. Therefore, other itch-targeted therapies are needed for use in this disease. OBJECTIVE: We sought to evaluate the current evidence regarding the mechanism of action and treatments for pruritus associated with CTCL. METHODS: An explicit and thorough search was restricted to all peer-reviewed literature available through MEDLINE (1950 to September 2011) and PubMed. Search terms used were "pruritus," "cutaneous T-cell lymphoma," "CTCL," "mycosis fungoides," "MF," and "Sézary syndrome." All studies that involved pruritus in CTCL, mycosis fungoides, or Sézary syndrome were evaluated by all 3 authors. RESULTS: The current literature helps to identify therapies and possible mechanisms for treating patients with CTCL-associated pruritus. LIMITATION: Most studies were preclinical. Only studies involving mechanisms of action or treatment were included. CONCLUSION: A guideline is necessary to assist in the treatment of pruritus in CTCL and additional studies are necessary to uncover the exact mechanism or mechanisms of action.


Asunto(s)
Linfoma Cutáneo de Células T/complicaciones , Prurito/etiología , Prurito/terapia , Neoplasias Cutáneas/complicaciones , Humanos
17.
J Biol Chem ; 285(34): 26149-61, 2010 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-20530479

RESUMEN

Sodium channel Na(v)1.6 is essential for neuronal excitability in central and peripheral nervous systems. Loss-of-function mutations in Na(v)1.6 underlie motor disorders, with homozygous-null mutations causing juvenile lethality. Phosphorylation of Na(v)1.6 by the stress-induced p38 MAPK at a Pro-Gly-Ser(553)-Pro motif in its intracellular loop L1 reduces Na(v)1.6 current density in a dorsal root ganglion-derived cell line, without changing its gating properties. Phosphorylated Pro-Gly-Ser(553)-Pro motif is a putative binding site to Nedd4 ubiquitin ligases, and we hypothesized that Nedd4-like ubiquitin ligases may contribute to channel ubiquitination and internalization. We report here that p38 activation in hippocampal neurons from wild-type mice, but not from Scn8a(medtg) mice that lack Na(v)1.6, reduces tetrodotoxin-S sodium currents, suggesting isoform-specific modulation of Na(v)1.6 by p38 in these neurons. Pharmacological block of endocytosis completely abolishes p38-mediated Na(v)1.6 current reduction, supporting our hypothesis that channel internalization underlies current reduction. We also report that the ubiquitin ligase Nedd4-2 interacts with Na(v)1.6 via a Pro-Ser-Tyr(1945) motif in the C terminus of the channel and reduces Na(v)1.6 current density, and we show that this regulation requires both the Pro-Gly-Ser-Pro motif in L1 and the Pro-Ser-Tyr motif in the C terminus. Similarly, both motifs are necessary for p38-mediated reduction of Na(v)1.6 current, whereas abrogating binding of the ubiquitin ligase Nedd4-2 to the Pro-Ser-Tyr motif results in stress-mediated increase in Na(v)1.6 current density. Thus, phosphorylation of the Pro-Gly-Ser-Pro motif within L1 of Na(v)1.6 is necessary for stress-induced current modulation, with positive or negative regulation depending upon the availability of the C-terminal Pro-Ser-Tyr motif to bind Nedd4-2.


Asunto(s)
Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Canales de Sodio/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Secuencias de Aminoácidos , Animales , Sitios de Unión , Electrofisiología , Hipocampo/citología , Humanos , Ratones , Ratones Endogámicos C57BL , Canal de Sodio Activado por Voltaje NAV1.6 , Ubiquitina-Proteína Ligasas Nedd4 , Neuronas/fisiología , Fosforilación
18.
Ann Neurol ; 65(6): 733-41, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19557861

RESUMEN

OBJECTIVE: Human and animal studies have shown that Na(v)1.7 sodium channels, which are preferentially expressed within nociceptors and sympathetic neurons, play a major role in inflammatory and neuropathic pain. Inherited erythromelalgia (IEM) has been linked to gain-of-function mutations of Na(v)1.7. We now report a novel mutation (V400M) in a three-generation Canadian family in which pain is relieved by carbamazepine (CBZ). METHODS: We extracted genomic DNA from blood samples of eight members of the family, and the sequence of SCN9A coding exons was compared with the reference Na(v)1.7 complementary DNA. Wild-type Na(v)1.7 and V400M cell lines were then analyzed using whole-cell patch-clamp recording for changes in activation, deactivation, steady-state inactivation, and ramp currents. RESULTS: Whole-cell patch-clamp studies of V400M demonstrate changes in activation, deactivation, steady-state inactivation, and ramp currents that can produce dorsal root ganglia neuron hyperexcitability that underlies pain in these patients. We show that CBZ, at concentrations in the human therapeutic range, normalizes the voltage dependence of activation and inactivation of this inherited erythromelalgia mutation in Na(v)1.7 but does not affect these parameters in wild-type Na(v)1.7. INTERPRETATION: Our results demonstrate a normalizing effect of CBZ on mutant Na(v)1.7 channels in this kindred with CBZ-responsive inherited erythromelalgia. The selective effect of CBZ on the mutant Na(v)1.7 channel appears to explain the ameliorative response to treatment in this kindred. Our results suggest that functional expression and pharmacological studies may provide mechanistic insights into hereditary painful disorders.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Carbamazepina/uso terapéutico , Eritromelalgia/tratamiento farmacológico , Eritromelalgia/genética , Mutación , Canales de Sodio/genética , Adulto , Línea Celular , Eritromelalgia/diagnóstico , Femenino , Humanos , Masculino , Mutación/efectos de los fármacos , Canal de Sodio Activado por Voltaje NAV1.7 , Linaje
19.
Am J Dermatopathol ; 31(1): 37-43, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19155723

RESUMEN

Pseudoepitheliomatous hyperplasia (PEH) in biopsies of CD30+ anaplastic large-cell lymphoma (ALCL) is present infrequently and is of unknown prognostic value and significance. Our goal was to review the clinicopathologic features of cases of ALCL with PEH, study their course, and review the literature on the subject. Biopsy specimens of all cases of CD30+ lymphoproliferative disorders (59) were retrieved from the files of Yale Dermatopathology Laboratory over a 17-year period and reviewed. We identified 4 cases of ALCL (7%) exhibiting prominent PEH. All 4 patients presented with 1 or 2 nodules. In 2 patients, the lesions spontaneously regressed within a few months after initial diagnosis. One patient chose to have an excision in which only a small number of CD30+ cells were present. We were unable to obtain follow-up for the fourth patient. In the spectrum of CD30+ lymphoproliferative disorders, cases of ALCL with PEH are infrequent. In addition to the 4 cases described here, in our review of the literature we found 35 cases of ALCL with PEH. Most of these patients present with 1 or a few lesions. In the majority of these cases, the lesions started showing evidence of clinical spontaneous regression and even complete resolution within a few months of initial diagnosis. The clinicopathologic correlation between ALCL and PEH has not been emphasized. Because most of these cases follow a relatively benign clinical course, we recommend a more conservative approach in the clinical management of these patients.


Asunto(s)
Antígeno Ki-1/metabolismo , Linfoma Anaplásico de Células Grandes/complicaciones , Linfoma Anaplásico de Células Grandes/patología , Enfermedades de la Piel/complicaciones , Enfermedades de la Piel/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Hiperplasia , Linfoma Anaplásico de Células Grandes/metabolismo , Masculino , Persona de Mediana Edad , Regresión Neoplásica Espontánea
20.
Br J Clin Pharmacol ; 58(5): 470-5, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15521893

RESUMEN

AIMS: To investigate the effect of monoamine oxidase A inhibition from a single oral dose of linezolid on the pressor response to intravenous (i.v.) tyramine, using positive and negative controls to validate the methodology. METHODS: This placebo-controlled, three-period crossover study was conducted in 12 healthy male volunteers. Each volunteer received either one oral dose of moclobemide (300 mg), linezolid (600 mg), or placebo tablet followed by an i.v. tyramine pressor test until an increase in systolic blood pressure of at least 30 mmHg above baseline occurred. Each study day was separated by a 7-day washout period. The dose of tyramine required to raise the blood pressure by 30 mmHg (TYR30) was calculated for each oral treatment by linear interpolation between log-transformed doses of i.v. tyramine. The influence of body mass index (BMI) on TYR30 was also investigated. RESULTS: The tyramine sensitivity factor (ratio of the geometric least square mean TYR30 for placebo and active oral treatment) was 1.8 [90% confidence interval (CI) 1.6, 2.0, P < 0.0001] for linezolid and 2.1 (90% CI 1.8, 2.4, P < 0.0001) for the positive control moclobemide. BMI had a statistically significant effect on TYR30. CONCLUSIONS: There was a significant difference in the pressor response to i.v. tyramine between linezolid and placebo. Moclobemide (positive control) and linezolid have a similar pressor response to i.v. tyramine. The statistically significant effect of BMI on TYR30 underlines the advantage of within-individual comparisons of treatments in order to reduce variability and provide more accurate treatment estimates.


Asunto(s)
Acetamidas/administración & dosificación , Presión Sanguínea/efectos de los fármacos , Moclobemida/farmacología , Inhibidores de la Monoaminooxidasa/farmacología , Oxazolidinonas/administración & dosificación , Tiramina/farmacología , Acetamidas/farmacología , Administración Oral , Adulto , Índice de Masa Corporal , Estudios Cruzados , Humanos , Infusiones Intravenosas , Linezolid , Masculino , Persona de Mediana Edad , Moclobemida/administración & dosificación , Inhibidores de la Monoaminooxidasa/administración & dosificación , Oxazolidinonas/farmacología , Tiramina/administración & dosificación
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