RESUMEN
Skin hyperpigmentation is mainly caused by excessive synthesis of melanin; however, there is still no safe and effective therapy for its removal. Here, we found that the dermal freezer was able to improve UVB-induced hyperpigmentation of guinea pigs without causing obvious epidermal damage. We also mimic freezing stimulation at the cellular level by rapid freezing and observed that freezing treatments <2.5 min could not decrease cell viability or induce cell apoptosis in B16F10 and Melan-A cells. Critically, melanin content and tyrosinase activity in two cells were greatly reduced after freezing treatments. The dramatic decrease in tyrosinase activity was associated with the downregulation of MITF, TYR, TRP-1 and TRP-2 protein expression in response to freezing treatments for two cells. Furthermore, our results first demonstrated that freezing treatments significantly reduced the levels of p-GSK3ß and ß-catenin and the nuclear accumulation of ß-catenin in B16F10 and Melan-A cells. Together, these data suggest that fast freezing treatments can inhibit melanogenesis-related gene expression in melanocytes by regulating the Wnt/ß-catenin signalling pathway. The inhibition of melanin production eventually contributed to the improvement in skin hyperpigmentation induced by UVB. Therefore, fast freezing treatments may be a new alternative of skin whitening in the clinic in the future.
Asunto(s)
Congelación , Melaninas , Melanocitos , Vía de Señalización Wnt , beta Catenina , Animales , Cobayas , Ratones , Apoptosis , beta Catenina/metabolismo , Supervivencia Celular , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Hiperpigmentación/terapia , Interferón Tipo I , Oxidorreductasas Intramoleculares/metabolismo , Melaninas/biosíntesis , Melanocitos/metabolismo , Factor de Transcripción Asociado a Microftalmía/metabolismo , Monofenol Monooxigenasa/metabolismo , Oxidorreductasas/metabolismo , Rayos UltravioletaRESUMEN
Hordenine is effective in treating hyperpigmentation, fighting diabetes and resisting fibrosis and acute inflammation. However, the role of Hordenine on hair growth has not been elucidated. Here, we found that Hordenine treatments significantly enhance proliferation of primary mouse dermal-papilla cells (DPCs) and increase the activity of DPCs in a dose-dependent manner. Additionally, Hordenine markedly promoted the elongation of the hair shaft in the model of in vitro-cultured mouse vibrissa follicle and accelerated hair regrowth in a mouse model of depilation-induced hair regeneration. Real-time PCR, Western Blot and immunofluorescent assays showed that nuclear ß-catenin and its downstream gene expression such as Lef1, Axin2, Cyclin D1 and ALP were greatly upregulated in DPCs and mouse hair follicles after Hordenine treatments. Moreover, the increased DPCs' proliferation and hair shaft elongation of cultured mouse vibrissa follicles induced by Hordenine treatments were rescued by a Wnt/ß-catenin signaling inhibitor, FH535. These data indicate that Hordenine can effectively enhance DPCs' activity and accelerate hair regrowth through activating the Wnt/ß-catenin signaling pathway. Therefore, these findings suggest Hordenine/its derivatives may be potentially used for preventing and treating alopecia in the future.
Asunto(s)
Folículo Piloso , Vía de Señalización Wnt , Ratones , Animales , beta Catenina/genética , beta Catenina/metabolismo , Células Cultivadas , Cabello/metabolismo , Proliferación CelularRESUMEN
BACKGROUND: Yohimbine hydrochloride (YH) is a prescription drug to treat erectile dysfunction. It also had potential in fighting high blood pressure and diabetic neuropathy as well as promoting weight loss. OBJECTIVE: The aim of the study is to investigate the anti-melanogenic function of yohimbine hydrochloride and reveal its underlying molecular mechanism. METHODS: B16F10 mouse melanoma cells, Melan-A murine melanocyte, Zebrafish embryos and C57BL/6 mouse ear skins were treated with different concentrations of YH. The extracellular and cellular melanin content was detected by spectrometry. The expression of microphthalmia-associated transcription factor (MITF), tyrosinase and the activities of Wnt/ß-catenin and p38/MAPK signal pathways were determined by RT-qPCR, Western blot analysis and immunofluorescent staining. RESULTS: Melanin production could be effectively inhibited by YH at the safe concentration in vitro and in vivo. Q-PCR and WB results showed that the expression of MITF and tyrosinase were strongly downregulated after YH treatments along with the reduction of tyrosinase activity. YH markedly inhibited ß-catenin nuclear accumulation and p38 phosphorylation in B16F10 cells compared with the untreated controls. Importantly, the increase of MITF expression induced by ß-catenin activator BIO and p38 activator anisomycin could be fully reversed by YH treatments. CONCLUSIONS: These results indicate that YH can function as an anti-melanogenic agent, at least in part, by inhibiting Wnt/ß-catenin and p38/MAPK signal pathways. Therefore, YH may be potentially used as a skin-whitening compound for preventing hyperpigmentation disorders in the future.
Asunto(s)
Melaninas , Melanoma Experimental , Animales , Línea Celular Tumoral , Ratones , Ratones Endogámicos C57BL , Factor de Transcripción Asociado a Microftalmía , Monofenol Monooxigenasa , Transducción de Señal , Yohimbina , Pez Cebra , beta Catenina , Proteínas Quinasas p38 Activadas por MitógenosRESUMEN
P2RY6 is highly expressed in skin keratinocytes, but its function in skin diseases is unclear. We use a two-step chemical induction method to induce mouse skin tumor formation. Multiple in vitro and in vivo assays were used to explore the role of P2RY6 in skin tumors. We report that P2ry6-deficient mice exhibit marked resistance to 7,12-dimethylbenz[a]anthracene/12-O-tetradecanoylphorbol-13-acetate (TPA)-induced skin papilloma formation compared with wild-type mice. Consistent with these findings, epidermal hyperplasia in response to TPA was suppressed in the P2ry6-knockout or MRS2578 (P2RY6 antagonist)-treated mice. The dramatic decrease in hyperplasia and tumorigenesis due to P2ry6 disruption was associated with the suppression of TPA-induced keratinocyte proliferation and inflammatory reactions. Notably, P2ry6 deletion prevented the TPA-induced increase in YAP nuclear accumulation and its downstream gene expression in an MST/LATS1-dependent manner. On TPA stimulation, enhanced activation of MAPK/extracellular signalâregulated kinase kinase 1 and ß-catenin were also impaired in P2ry6-knockout primary keratinocytes, tumor tissues, or MRS2578-treated HaCaT cells. Moreover, mutual promotion of the YAP and ß-catenin signaling pathways was observed in normal skin cells treated with TPA, whereas P2ry6 deletion could inhibit their crosstalk by regulating MAPK/extracellular signalâregulated kinase kinase 1. Thus, P2RY6 is a critical positive regulator of skin tumorigenesis through the modulation of the Hippo/YAP and Wnt/ß-catenin signaling pathways.
Asunto(s)
Receptores Purinérgicos P2 , Neoplasias Cutáneas , Vía de Señalización Wnt , 9,10-Dimetil-1,2-benzantraceno/toxicidad , Animales , Carcinogénesis/patología , Hiperplasia/patología , Queratinocitos/metabolismo , Ratones , Receptores Purinérgicos P2/metabolismo , Piel/patología , Neoplasias Cutáneas/inducido químicamente , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Acetato de Tetradecanoilforbol/toxicidad , Proteínas Señalizadoras YAP/metabolismo , beta Catenina/metabolismoRESUMEN
BACKGROUND: REGγ acts as a proteasome activating factor mediating proteasome degradation of substrate proteins in an ATP and ubiquitination independent manner and also as an important regulator of cell cycle, proliferation and apoptosis. Hair cycle involves dynamic, continuous morphological changes of three stages (anagen, catagen and telogen). OBJECTIVE: The function of REGγ in hair cycling is still unclear. METHODS: Here, we used REGγ knockout 293 T cells, inducible 293WT and 293N151Y cell, REGγ knockout mice to identify the novel molecular mechanism of REGγ in regulating hair follicle stem cells. RESULTS: In the present study, we found that REGγ deletion markedly delayed the transition of hair follicles from telogen to anagen and hair regeneration in mice. We also observed significant decrease of hair follicle stem cell number, stem-like property and proliferation ability. Interestingly, the results from real-time PCR, FACS, Western Blot and immunofluorescent analysis showed that REGγ deletion could greatly downregulate Lgr5 expression in the hair follicles. Meanwhile, REGγ was demonstrated to directly interact with LHX2 and promotes its degradation. Importantly, REGγ specific deletion in Lgr5+ stem cells induced the marked delay of hair regeneration after depilation. CONCLUSION: These data together indicate that REGγ was a new mediator of Lgr5 expression in hair follicle at least partly by promoting the degradation of its suppressive transcription factor LHX2. It seemed that REGγ regulated hair anagen entry and hair regrowth by activating Lgr5 positive hair follicle stem cells.
Asunto(s)
Autoantígenos/metabolismo , Folículo Piloso/crecimiento & desarrollo , Proteínas con Homeodominio LIM/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Células Madre/fisiología , Factores de Transcripción/metabolismo , Animales , Apoptosis/fisiología , Autoantígenos/genética , Proliferación Celular/fisiología , Técnicas de Silenciamiento del Gen , Células HEK293 , Folículo Piloso/metabolismo , Humanos , Queratinocitos , Masculino , Ratones , Ratones Noqueados , Cultivo Primario de Células , Complejo de la Endopetidasa Proteasomal/genética , Proteolisis , Receptores Acoplados a Proteínas G/metabolismo , Regeneración/fisiología , Regulación hacia Arriba/fisiologíaRESUMEN
It is known that LGR4 plays an important role in hair follicle (HF) development, but the impact of LGR4 on the hair cycle is still unclear. In this study, we have found that K14-Cre-mediated skin epithelia-specific deletion of Lgr4 results in delayed anagen entry during the physiological hair cycle and compromised HF regeneration upon transplantation. We show that, although Lgr4 deletion does not appear to affect the number of quiescent HF stem cells, it leads to reduced numbers of LGR5+ and actively proliferating stem cells in the HFs. Moreover, LGR4-deficient HFs show molecular changes consistent with decreased mTOR and Wnt signaling but upregulated BMP signaling. Importantly, the reactivation of the protein kinase B pathway by injecting the protein kinase B activator SC79 in Lgr4-/- mice can effectively reverse the hair cycle delay. Together, these data suggest that LGR4 promotes the normal hair cycle by activating HF stem cells and by influencing the activities of multiple signaling pathways that are known to regulate HF stem cells. Our study also implicates LGR4 as a potential target for treating hair disorder in the future.
Asunto(s)
Células Madre Adultas/fisiología , Folículo Piloso/crecimiento & desarrollo , Receptores Acoplados a Proteínas G/metabolismo , Acetatos/administración & dosificación , Células Madre Adultas/efectos de los fármacos , Animales , Benzopiranos/administración & dosificación , Proteínas Morfogenéticas Óseas/metabolismo , Proliferación Celular/efectos de los fármacos , Femenino , Folículo Piloso/citología , Folículo Piloso/efectos de los fármacos , Masculino , Ratones , Ratones Noqueados , Modelos Animales , Proteínas Proto-Oncogénicas c-akt/agonistas , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores Acoplados a Proteínas G/genética , Regeneración/efectos de los fármacos , Piel/citología , Piel/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Regulación hacia Arriba , Vía de Señalización Wnt/efectos de los fármacosRESUMEN
Anaplastic thyroid cancer (ATC) is the most aggressive human thyroid malignancy, characterized by dedifferentiation and resistance to radioiodine therapy. The underlying mechanisms regulating ATC dedifferentiation are largely unknown. Here, we show that REGγ, a noncanonical proteasome activator highly expressed in ATC, is an important regulator of differentiation in ATC cells. Ablation of REGγ significantly restored expression of thyroid-specific genes, enhanced iodine uptake, and improved the efficacy of 131I therapy in ATC xenograft models. Mechanistically, REGγ directly binds to the TGF-ß signaling antagonist Smad7 and promotes its degradation, leading to the activation of the TGF-ß signal pathway. With gain- and loss-of-function studies, we demonstrate that Smad7 is an important mediator for the REGγ function in ATC cell dedifferentiation, which is supported by expression profiles in human ATC tissues. It seems that REGγ impinges on repression of thyroid-specific genes and promotion of tumor malignancy in ATC cells by activating the TGF-ß signal pathway via degradation of Smad7. Thus, REGγ may serve as a novel therapeutic target for allowing radioiodine therapy in anaplastic thyroid cancer patients with poor prognosis.
Asunto(s)
Autoantígenos/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteína smad7/metabolismo , Carcinoma Anaplásico de Tiroides/metabolismo , Neoplasias de la Tiroides/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Diferenciación Celular , Línea Celular , Humanos , Transducción de Señal , Carcinoma Anaplásico de Tiroides/patología , Carcinoma Anaplásico de Tiroides/radioterapia , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/radioterapiaRESUMEN
BACKGROUND: Fargesin is commonly used in the treatment of allergic rhinitis, inflammation, sinusitis and headache. OBJECTIVE: The aim of the study is to investigate a new function of fargesin against melanin production and its underlying molecular mechanism. METHODS: B16F10 mouse melanoma cells, Melan-a and human epidermal melanocytes were treated with different concentrations of fargesin for the indicated time. The extracellular and cellular melanin content was detected by spectrometry at 490 nm and 405 nm, respectively. RT-qPCR and Western blot analysis were used to exam the expression of melanogenic enzymes and the activities of PKA/CREB and p38 MAPK pathway components. Zebrafish was used as an in vivo model for studying the function of fargesin in regulating melanogenesis. RESULTS: Fargesin effectively inhibited melanin production at moderate dose in mouse B16F10 melanoma cells, normal melanocyte cell lines and zebrafish. The expression of microphthalmia-associated transcription factor (MITF), its downstream melanogenic enzymes and tyrosinase activity were also strongly reduced by fargesin. Moreover, the increase of melanin production induced by UVB and forskolin could be fully reversed by fargesin treatment. Fargesin also effectively inhibited the activation of PKA/CREB and p38 MAPK as well as their interactions, which in turn is responsible for the expression of MITF and melanogenic enzymes. CONCLUSIONS: These results show that fargesin can function as an anti-melanogenic agent, at least in part, by inhibiting PKA/CREB and p38/MAPK signaling pathways. Therefore, fargesin and its derivatives may potentially be used for preventing hyperpigmentation disorders in the future.
Asunto(s)
Benzodioxoles/farmacología , Hiperpigmentación/tratamiento farmacológico , Lignanos/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Melaninas/biosíntesis , Melanocitos/efectos de los fármacos , Animales , Benzodioxoles/uso terapéutico , Línea Celular Tumoral , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Evaluación Preclínica de Medicamentos , Embrión no Mamífero , Humanos , Lignanos/uso terapéutico , Melanocitos/metabolismo , Ratones , Modelos Animales , Pez CebraRESUMEN
Purpose: Colorectal cancer is one of the most commonly diagnosed cancers closely associated with inflammation and hyperactive growth. We previously demonstrated a regulatory circuit between the proteasome activator REGγ and NF-kappaB (NF-κB) during colon inflammation, known to be important in the development of colitis-associated cancer as well as sporadic colorectal cancer. How the inflammatory microenvironment affects the Hippo pathway during colorectal cancer development is largely unknown.Experimental Design: Here, we used REGγ-deficient colon cancer cell lines, REGγ knockout mice, and human colorectal cancer samples to identify the novel molecular mechanism by which REGγ functions as an oncoprotein in the development of colorectal cancer.Results: REGγ can directly interact with Lats1 and promote its degradation, which facilitates Yes-associated protein (YAP) activation in colon cancer cells. REGγ deficiency significantly attenuated colon cancer growth, associated with decreased YAP activity. Suppression of tumor growth due to REGγ depletion was overcome by constitutively active YAP. Surprisingly, reciprocal activation of the YAP and NF-κB pathways was observed in human colon cancer cells. REGγ overexpression was found in over 60% of 172 colorectal cancer specimens, highly correlating with the elevation of YAP and p65. Postoperative follow-up revealed a significantly lower survival rate in patients with concomitantly high expression of REGγ, YAP, and p-p65.Conclusions: REGγ could be a master regulator during colorectal cancer development to promote YAP signaling and reinforce cross-talks between inflammation and growth pathways, and REGγ might be a new marker for prognosis of colorectal cancer patients. Clin Cancer Res; 24(8); 2015-25. ©2018 AACR.
Asunto(s)
Autoantígenos/metabolismo , Proteínas de Ciclo Celular/metabolismo , Neoplasias del Colon/metabolismo , FN-kappa B/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Factores de Transcripción/metabolismo , Animales , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Neoplasias del Colon/genética , Neoplasias del Colon/mortalidad , Neoplasias del Colon/patología , Modelos Animales de Enfermedad , Xenoinjertos , Vía de Señalización Hippo , Humanos , Ratones , Pronóstico , Unión Proteica , Proteolisis , Análisis de SupervivenciaRESUMEN
The 1064-nm Q-switched Nd:YAG laser is demonstrated to be effective for non-ablative skin rejuvenation, but the molecular mechanism by which dermis responses to laser-induced damage and initiates skin remodeling is still unclear. HaCaT cells and 3T3 skin fibroblasts were irradiated with the 1064-nm Q-switched Nd:YAG laser at the different doses. Then, cells were collected and lysed for PCR and Western blot analysis. Cell viability was detected by Cell Counting Kit-8 (CCK-8) before and after laser irradiation. The expressions of S100A8, advanced glycosylation end product-specific receptor (RAGE) and inflammatory cytokines in two cell lines were markedly upregulated after laser treatments. The PCR, Western blot, and ELISA analysis showed the significant increase of type I and III procollagen in the 3T3 cells treated with the 1064-nm laser. Interestingly, si S100A8 effectively inhibited the expression of cytokines and collagen, while S100A8 treatments significantly increased them. P-p38 and p-p65 levels were also elevated after the 1064-nm laser irradiation, which is positively related with S100A8. Cell viability and reactive oxygen species (ROS) levels were not changed, while the content of superoxidase dismutase (SOD) in two cells was increased after laser irradiation. Our results demonstrated that the overexpression of S100A8 induced by the 1064-nm laser irradiation triggered inflammatory reactions in skin cells. The inflammatory microenvironment and improvement of skin antioxidant capacity contribute to new collagen synthesis in the skin cells. Thus, S100A8 was required for laser-induced new collagen synthesis in skin cells. p38/MAPK and NF-κB signal pathways were involved in S100A8-mediated inflammatory reactions in response to laser irradiation.
Asunto(s)
Calgranulina A/metabolismo , Láseres de Estado Sólido/uso terapéutico , Piel/metabolismo , Piel/efectos de la radiación , Animales , Calgranulina A/genética , Línea Celular , Forma de la Célula/efectos de la radiación , Supervivencia Celular/efectos de la radiación , Colágeno/biosíntesis , Colágeno/metabolismo , Femenino , Fibroblastos/metabolismo , Fibroblastos/efectos de la radiación , Humanos , Inflamación/patología , Queratinocitos/metabolismo , Queratinocitos/efectos de la radiación , Ratones , FN-kappa B/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Rejuvenecimiento , Transducción de Señal , Superóxido Dismutasa/metabolismo , Regulación hacia Arriba/genética , Regulación hacia Arriba/efectos de la radiación , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
It has been reported that the proteasome activator REGγ is associated with multiple oncogenic pathways in human cancers. However, the role of REGγ in the development of melanoma and the underlying mechanisms remain unclear. In this study, we attempted to investigate the effects of REGγ on human melanoma cell proliferation in vitro and in vivo. We demonstrated that knockdown of REGγ inhibited melanoma cell growth and arrested melanoma cell at G1 phase. Furthermore, depletion of REGγ also inhibited the xenograft growth of human melanoma. Mechanistically, REGγ activates Wnt/ß-catenin signal pathway by degrading GSK-3ß in melanoma cell lines and mouse models. Transient knockdown of ß-catenin effectively blocked cell proliferation in REGγ wild-type melanoma cells. In human melanoma samples, REGγ was overexpressed and positively correlated with ß-catenin levels. This study demonstrates that REGγ is a central molecule in the development of melanoma by regulating Wnt/ß-catenin pathway. This suggests that targeting REGγ could be an alternative therapeutic approach for melanoma.
Asunto(s)
Autoantígenos/genética , Proliferación Celular/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Melanoma/genética , Complejo de la Endopetidasa Proteasomal/genética , Vía de Señalización Wnt/genética , beta Catenina/metabolismo , Animales , Autoantígenos/metabolismo , Línea Celular Tumoral , Femenino , Puntos de Control de la Fase G1 del Ciclo Celular , Técnicas de Silenciamiento del Gen , Glucógeno Sintasa Quinasa 3 beta/genética , Humanos , Melanoma/metabolismo , Ratones , Trasplante de Neoplasias , Complejo de la Endopetidasa Proteasomal/metabolismo , ARN Mensajero/metabolismo , ARN Interferente Pequeño , beta Catenina/genéticaRESUMEN
Forkhead box D3 (FOXD3), as a transcriptional repressor, is well known to be involved in the regulation of development. Although FoxD3 is associated with several cancers, its role in colon cancer and the underlying mechanism are still unclear. Here, we first showed that FOXD3 knockdown dramatically increased the proliferation of human colon cancer cells, enhanced cell invasive ability and inhibited cell apoptosis. In vivo xenograft studies confirmed that the FOXD3-knockdown cells were more tumorigenic than the controls. Silencing FOXD3 markedly activated EGFR/Ras/Raf/MEK/ERK pathway in human colon cancer cells. In addition, blocking EGFR effectively decreased the activity of MAPK induced by FOXD3 knockdown. In human cancer tissue, the expression of FOXD3 was reduced, however, the EGFR/Ras/Raf/MEK/ERK pathway was activated. Our study indicates that FOXD3 may play a protective role in human colon formation by regulating EGFR/Ras/Raf/MEK/ERK signal pathway. It is proposed that FOXD3 may have potential as a new therapeutic target in human colon cancer treatment.
Asunto(s)
Neoplasias del Colon/patología , Regulación hacia Abajo , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Animales , Células CACO-2 , Proliferación Celular , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Receptores ErbB/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Células HCT116 , Humanos , Sistema de Señalización de MAP Quinasas , Ratones , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Trasplante de Neoplasias , Quinasas raf/metabolismo , Proteínas ras/metabolismoRESUMEN
Lgr4 is a member of the leucine-rich, G protein-coupled receptor family of proteins, and has recently been shown to augment Wnt/ß-catenin signaling via binding to Wnt agonists R-spondins. It plays an important role in skin development, but its involvement in skin tumorigenesis is unclear. Here, we report that mice deficient for Lgr4 are resistant to 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced keratinocyte proliferation and papilloma formation. We show that TPA treatment activates MEK1, ERK1/2 and downstream effector AP-1 in wild-type (WT) epidermal cells and mice, but not in cells or mice where Lgr4 is depleted. Wnt/ß-catenin signaling is also dramatically activated by TPA treatment, and this activation is abolished when Lgr4 is deleted. We provide evidences that blocking both MEK1/ERK1/2 and Wnt/ß-catenin pathways prevents TPA-induced increase in the expression of Ccnd1 (cyclin D1), a known Wnt/ß-catenin target gene, and that the activation of MEK1/ERK1/2 pathway lies upstream of Wnt/ß-catenin signal pathway. Collectively, our findings identify Lgr4 as a critical positive factor for skin tumorigenesis by mediating the activation of MEK1/ERK1/2 and Wnt/ß-catenin pathways.
Asunto(s)
Transformación Celular Neoplásica/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Queratinocitos/enzimología , MAP Quinasa Quinasa 1/metabolismo , Neoplasias Experimentales/enzimología , Papiloma/enzimología , Receptores Acoplados a Proteínas G/metabolismo , Neoplasias Cutáneas/enzimología , Vía de Señalización Wnt , Animales , Línea Celular Tumoral , Proliferación Celular , Transformación Celular Neoplásica/inducido químicamente , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Ciclina D1/genética , Ciclina D1/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/genética , Predisposición Genética a la Enfermedad , Humanos , Queratinocitos/patología , Ratones Noqueados , Neoplasias Experimentales/inducido químicamente , Neoplasias Experimentales/genética , Neoplasias Experimentales/patología , Papiloma/inducido químicamente , Papiloma/genética , Papiloma/patología , Fenotipo , Interferencia de ARN , Receptores Acoplados a Proteínas G/deficiencia , Receptores Acoplados a Proteínas G/genética , Neoplasias Cutáneas/inducido químicamente , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Acetato de Tetradecanoilforbol , Factores de Tiempo , Factor de Transcripción AP-1/metabolismo , TransfecciónRESUMEN
Non-small cell lung cancer (NSCLC) is the most common type of lung cancer and the five-year survival rate is lower in advanced NSCLC patients. Chemotherapy is a widely used strategy in NSCLC treatment, but is usually limited by poor therapeutic efficacy and adverse effects. Therefore, a new therapeutic regimen is needed for NSCLC treatment. Gene therapy is a new strategy in the treatment of NSCLC. However, the lack of efficient and low toxic vectors remains the major obstacle. Here, we developed a biocompatible dendrimer as a non-viral vector for the delivery of mouse double minute2 (MDM2) siRNA in vitro and in vivo to treat NSCLC. The triazine-modified dendrimer efficiently stimulates the down-regulation of MDM2 gene in NSCLC PC9 cells, which induces significant cell apoptosis through the activation of apoptosis markers such as caspase-8 and poly(ADP-ribose) polymerase (PARP) cleavage. Furthermore, the dendrimer/MDM2 siRNA polyplexes showed excellent activity in the inhibition of tumor growth in a PC9 xenograft tumor model. These results suggested that inhibition the expression of MDM2 might be a potential target in NSCLC treatment.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogénicas c-mdm2/genética , ARN Interferente Pequeño/genética , Animales , Apoptosis/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/terapia , Línea Celular Tumoral , Dendrímeros/química , Femenino , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/terapia , Ratones Endogámicos BALB C , Ratones Desnudos , Interferencia de ARN , ARN Interferente Pequeño/química , Tratamiento con ARN de Interferencia/métodos , Triazinas/química , Ensayos Antitumor por Modelo de Xenoinjerto/métodosRESUMEN
The 800-nm diode laser is widely used for hair removal and also promotes collagen synthesis, but the molecular mechanism by which dermis responses to the thermal damage induced by the 800-nm diode laser is still unclear. Ten 2-month-old mice were irradiated with the 800-nm diode laser at 20, 40, and 60 J/cm(2), respectively. Skin samples were taken for PCR, Western blot analysis, and histological study at day 3 or 30 after laser irradiation. The expression of S100a8 and its two receptors (advanced glycosylation end product-specific receptor, RAGE and toll-like receptor 4, TRL4) was upregulated at day 3 after laser treatments. P-p65 levels were also elevated, causing the increase of cytokine (tumor necrosis factor, TNF-α and interleukin 6, IL-6) and MMPs (MMP1a, MMP9). At day 30, PCR and Western blot analysis showed significant increase of type I and III procollagen in the dermis treated with laser. Importantly, skin structure was markedly improved in the laser-irradiated skin compared with the control. Thus, it seemed that S100a8 upregulation triggered NF-κB signal pathway through RAGE and TLR4, responding to laser-induced dermis wound healing. The involvement of the NF-κB pathway in MMP gene transcription promoted the turnover of collagen in the skin, accelerating new collagen synthesis.
Asunto(s)
Colágeno/metabolismo , Láseres de Semiconductores/uso terapéutico , Terapia por Luz de Baja Intensidad/métodos , Transducción de Señal , Piel/efectos de la radiación , Animales , Calgranulina A/metabolismo , Colágeno/genética , Técnicas Cosméticas , Femenino , Expresión Génica/efectos de la radiación , Interleucina-6/metabolismo , Metaloproteinasa 13 de la Matriz/genética , Metaloproteinasa 13 de la Matriz/metabolismo , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , Ratones , FN-kappa B/metabolismo , Piel/metabolismo , Envejecimiento de la Piel/efectos de la radiación , Factor de Necrosis Tumoral alfa/metabolismo , Regulación hacia ArribaRESUMEN
BACKGROUND: Naringin is a bioflavonoid and has free radical scavenging and anti-inflammatory properties. METHODS: We examined the effects of naringin on skin after ultraviolet radiation B (UVB) irradiation and the signal pathways by in vitro and in vivo assay. RESULTS: HaCaT cells pretreated with naringin significantly inhibited UVB induced-cell apoptosis and production of intracellular reactive oxygen species (ROS). The expressions of interleukin-1ß (IL-1ß), interleukin-6 (IL-6), interleukin-8 (IL-8) and cyclooxygenase-2 (COX-2) in HaCaT cells pretreated with naringin were decreased compared with the only UVB group. Also, the activation of p38 induced by UVB in HaCaT cells was reversed by naringin treatments. The inhibition function of naringin on p38 activity was more obvious than JNK. In vivo, topical treatments with naringin prevented the increase of epidermal thickness, IL-6 production, cell apoptosis and the overexpression of COX-2 in BALB/c mice skin irradiated with UVB. Naringin treatment also markedly blocked the activation of p38 in response to UVB stimulation in the mouse skin. CONCLUSION: Naringin can effectively protect against UVB-induced keratinocyte apoptosis and skin damage by inhibiting ROS production, COX-2 overexpression and strong inflammation reactions. It seemed that naringin played its role against UVB-induced skin damage through inhibition of mitogen-activated protein kinase (MAPK)/p38 activation.
Asunto(s)
Flavanonas/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Piel/efectos de los fármacos , Piel/efectos de la radiación , Rayos Ultravioleta/efectos adversos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Ciclooxigenasa 2/metabolismo , Femenino , Humanos , Inflamación/tratamiento farmacológico , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Queratinocitos/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Especies Reactivas de Oxígeno/metabolismo , Piel/metabolismoRESUMEN
Increasing incidence of inflammatory bowel disorders demands a better understanding of the molecular mechanisms underlying its multifactorial aetiology. Here we demonstrate that mice deficient for REGγ, a proteasome activator, show significantly attenuated intestinal inflammation and colitis-associated cancer in dextran sodium sulfate model. Bone marrow transplantation experiments suggest that REGγ's function in non-haematopoietic cells primarily contributes to the phenotype. Elevated expression of REGγ exacerbates local inflammation and promotes a reciprocal regulatory loop with NFκB involving ubiquitin-independent degradation of IκBÉ. Additional deletion of IκBÉ restored colitis phenotypes and inflammatory gene expression in REGγ-deficient mice. In sum, this study identifies REGγ-mediated control of IκBÉ as a molecular mechanism that contributes to NFκB activation and promotes bowel inflammation and associated tumour formation in response to chronic injury.
Asunto(s)
Autoantígenos/metabolismo , Colitis/enzimología , Quinasa I-kappa B/metabolismo , FN-kappa B/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Animales , Colitis/inducido químicamente , Colitis/complicaciones , Neoplasias del Colon/etiología , Sulfato de Dextran , Células HCT116 , Células HEK293 , Humanos , Mucosa Intestinal/metabolismo , Ratones Endogámicos C57BL , Ratones NoqueadosRESUMEN
Wnt-ß-catenin signaling participates in the epithelial-mesenchymal transition (EMT) in a variety of cancers; however, its role in lung cancer induced bone metastasis and the underlying mechanisms remain unclear. Here, we demonstrate that ß-catenin, Snail1 and Zeb1 were significantly upregulated in bone metastasis tissues from human and mouse compared with the normal controls. E-cadherin expression is negatively regulated by Zeb1, Snail1 and ß-catenin during bone metastasis tissues induced by lung cancer. Knocking down Zeb1 and Snail1 in lung cancer cell lines showed increased E-cadherin mRNA expression and less invasion compared with the original cell lines. In addition, ß-catenin knockdown led to the increase of E-cadherin and the decrease of Zeb1 and Snail1, which in turn inhibited the invasive properties of lung cancer. Our results demonstrated that Wnt signaling through Snail1 and Zeb1 regulates bone metastasis in lung cancer.
RESUMEN
BACKGROUND: Tyrosinase (TYR) is the key enzyme controlling the production of melanin. Very few papers have reported that andrographolide can inhibit melanin content. OBJECTIVE: To investigate the effects of andrographolide on melanin synthesis. METHODS: Cell viability, melanin content, TYR activity, transcriptional and protein expression levels of TYR family and other kinds of proteins involved in melanogenesis were measured after the treatments of andrographolide. RESULTS: It was found that andrographolide decreased melanin content, TYR activity and transcriptional and protein expression of TYR family and microphthalmia-associated transcription factor (MITF) in B16F10 melanoma cells. Data showed andrographolide also decreased melanin content and TYR content in ultraviolet B (UVB) irradiation induced brown guinea pigs. Moreover, we found that melanin content and TYR activity were effectively inhibited in Human Epidermis Melanocyte (HEM) treated with andrographolide at the medium concentrations without apparent effect on cell viability. Results in experiments treated with MG-132 or cycloheximide (CHX) showed that andrographolide lowered the content of ß-catenin in cell nucleus resulting from accelerating the degradation of ß-catenin. Phosphorylation of glycogen synthase kinase 3ß (GSK3ß) and Akt decreased simultaneously. 6-Bromoindirubin-3'-oxime (BIO, inhibitor of GSK3ß) and insulin-like growth factors-1 (IGF-1, activator of Akt) could reverse the decline of ß-catenin in B16F10 cells induced by andrographolide. CONCLUSION: These results demonstrate that andrographolide can effectively suppress melanin content and TYR activity in B16F10 cells, HEM cells and UVB-induced brown guinea pig skin by decreasing phosphorylation of GSK3ß dependent on Akt, promoting the degradation of ß-catenin, inhibiting ß-catenin into the nucleus and decreasing the expression of MITF and TYR family. Data indicate that andrographolide may be a potential whiting agent which can have great market in cosmetics and in clinical such as curing hyperpigmentation disorders.
Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Diterpenos/farmacología , Melaninas/biosíntesis , Melanoma Experimental/enzimología , Biosíntesis de Proteínas/efectos de los fármacos , Vía de Señalización Wnt/efectos de los fármacos , Animales , Línea Celular Tumoral , Supervivencia Celular , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Cobayas , Humanos , Melanocitos , Melanoma Experimental/genética , Melanoma Experimental/metabolismo , Factor de Transcripción Asociado a Microftalmía/genética , Factor de Transcripción Asociado a Microftalmía/metabolismo , Monofenol Monooxigenasa/metabolismo , Biosíntesis de Proteínas/efectos de la radiación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Rayos Ultravioleta , beta Catenina/metabolismoRESUMEN
Here we report that mice deficient for the proteasome activator, REGγ, exhibit a marked resistance to TPA (12-O-tetradecanoyl-phorbol-13-acetate)-induced keratinocyte proliferation, epidermal hyperplasia and onset of papillomas compared with wild-type counterparts. Interestingly, a massive increase of REGγ in skin tissues or cells resulting from TPA induces activation of p38 mitogen-activated protein kinase (MAPK/p38). Blocking p38 MAPK activation prevents REGγ elevation in HaCaT cells with TPA treatment. AP-1, the downstream effector of MAPK/p38, directly binds to the REGγ promoter and activates its transcription in response to TPA stimulation. Furthermore, we find that REGγ activates Wnt/ß-catenin signalling by degrading GSK-3ß in vitro and in cells, increasing levels of CyclinD1 and c-Myc, the downstream targets of ß-catenin. Conversely, MAPK/p38 inactivation or REGγ deletion prevents the increase of cyclinD1 and c-Myc by TPA. This study demonstrates that REGγ acts in skin tumorigenesis mediating MAPK/p38 activation of the Wnt/ß-catenin pathway.