Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 2 de 2
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Carcinogenesis ; 37(1): 72-80, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26586792

RESUMEN

Protein kinase C epsilon (PKCε), a Ca(2+)-independent phospholipid-dependent serine/threonine kinase, is among the six PKC isoforms (α, δ, ε, η, µ, ζ) expressed in both mouse and human skin. Epidermal PKCε level dictates the susceptibility of PKCε transgenic (TG) mice to the development of cutaneous squamous cell carcinomas (SCC) elicited either by repeated exposure to ultraviolet radiation (UVR) or by using the DMBA initiation-TPA (12-O-tetradecanoylphorbol-13-acetate) tumor promotion protocol (Wheeler,D.L. et al. (2004) Protein kinase C epsilon is an endogenous photosensitizer that enhances ultraviolet radiation-induced cutaneous damage and development of squamous cell carcinomas. Cancer Res., 64, 7756-7765). Histologically, SCC in TG mice, like human SCC, is poorly differentiated and metastatic. Our earlier studies to elucidate mechanisms of PKCε-mediated development of SCC, using either DMBA-TPA or UVR, indicated elevated release of cytokine TNFα. To determine whether TNFα is essential for the development of SCC in TG mice, we generated PKCε transgenic mice/TNFα-knockout (TG/TNFαKO) by crossbreeding TNFαKO with TG mice. We now present that deletion of TNFα in TG mice inhibited the development of SCC either by repeated UVR exposures or by the DMBA-TPA protocol. TG mice deficient in TNFα elicited both increase in SCC latency and decrease in SCC incidence. Inhibition of UVR-induced SCC development in TG/TNFαKO was accompanied by inhibition of (i) the expression levels of TNFα receptors TNFRI and TNFRII and cell proliferation marker ornithine decarboxylase and metastatic markers MMP7 and MMP9, (ii) the activation of transcription factors Stat3 and NF-kB and (iii) proliferation of hair follicle stem cells and epidermal hyperplasia. The results presented here provide the first genetic evidence that TNFα is linked to PKCε-mediated sensitivity to DMBA-TPA or UVR-induced development of cutaneous SCC.


Asunto(s)
Carcinoma de Células Escamosas/prevención & control , Proteína Quinasa C-epsilon/genética , Neoplasias Cutáneas/prevención & control , Factor de Necrosis Tumoral alfa/deficiencia , Factor de Necrosis Tumoral alfa/genética , 9,10-Dimetil-1,2-benzantraceno , Animales , Carcinogénesis/inducido químicamente , Carcinogénesis/genética , Carcinogénesis/efectos de la radiación , Carcinógenos , Carcinoma de Células Escamosas/etiología , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Supervivencia Celular/efectos de la radiación , Femenino , Masculino , Ratones , Ratones Noqueados , Ratones Transgénicos , Proteína Quinasa C-epsilon/biosíntesis , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Acetato de Tetradecanoilforbol , Rayos Ultravioleta
2.
J Invest Dermatol ; 135(4): 1098-1107, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25337691

RESUMEN

We present here that heat-shock protein 90 (Hsp90) inhibitor 17-(allylamino)-17-demethoxygeldanamycin (17AAG), when topically applied to mouse skin, inhibits UVR-induced development of cutaneous squamous cell carcinoma (SCC). In these experiments, DMSO:acetone (1:40 v/v) solution of 17AAG (500 nmol) was applied topically to mouse skin in conjunction with each UVR exposure (1.8 kJ m(-2)). The UVR source was Kodacel-filtered FS-40 sun lamps (approximately 60% UVB and 40% UVA). In independent experiments with three separate mouse lines (SKH-1 hairless mice, wild-type FVB, and protein kinase C epsilon (PKCɛ)-overexpressing transgenic FVB mice), 17AAG treatment increased the latency and decreased both the incidence and multiplicity of UVR-induced SCC. Topical 17AAG alone or in conjunction with UVR treatments elicited neither skin nor systemic toxicity. 17AAG-caused inhibition of SCC induction was accompanied by a decrease in UVR-induced (1) hyperplasia, (2) Hsp90ß-PKCɛ interaction, and (3) expression levels of Hsp90ß, Stat3, pStat3Ser727, pStat3Tyr705, pAktSer473, and matrix metalloproteinase (MMP). The results presented here indicate that topical Hsp90 inhibitor 17AAG is effective in prevention of UVR-induced epidermal hyperplasia and SCC. One may conclude from the preclinical data presented here that topical 17AAG may be useful for prevention of UVR-induced inflammation and cutaneous SCC either developed in UVR-exposed or organ transplant population.


Asunto(s)
Benzoquinonas/farmacología , Proteínas HSP90 de Choque Térmico/metabolismo , Lactamas Macrocíclicas/farmacología , Melanoma/metabolismo , Neoplasias Inducidas por Radiación/metabolismo , Neoplasias Cutáneas/metabolismo , Acetona/química , Animales , Dimetilsulfóxido/química , Epidermis/metabolismo , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Humanos , Inflamación , Metaloproteinasas de la Matriz/metabolismo , Melanoma/prevención & control , Ratones , Neoplasias Inducidas por Radiación/prevención & control , Proteína Quinasa C-epsilon/metabolismo , Piel/efectos de los fármacos , Neoplasias Cutáneas/tratamiento farmacológico , Rayos Ultravioleta , Melanoma Cutáneo Maligno
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...