RESUMO
The hedgehog (Hh) pathway is essential for animal development, but aberrant activation promotes cancer growth. In this study, we show that GIPC3, a PDZ domain-containing protein with putative adaptor protein function, positively modulates Hh target gene expression in normal fibroblasts and melanoma cells and supports melanoma tumor growth. Using overexpression and epistasis studies, we show that Gipc3 potentiates Hh transcriptional output and that it modulates GLI-dependent transcription independently of Sufu. Whereas we find that GIPC3 protein does not interact with Hh pathway components, Ingenuity Pathway Analyses of GIPC3-interacting proteins identified by coimmunoprecipitation and mass spectrometry show an association with cancer pathogenesis. Subsequent interrogation of The Cancer Genome Atlas and the Human Protein Atlas databases reveals GIPC3 upregulation in many cancers. Using expression screens in selected groups of GIPC3-upregulated cancers with reported Hh pathway activation, we find a significant positive correlation of GIPC3 expression with Hh pathway components GLI1, GLI2, and GPR161 in melanoma lines. Consistently, GIPC3 knockdown in melanoma lines significantly reduces GLI1 and GLI2 expression, cell viability, colony formation, and allograft tumor growth. Our findings highlight previously unidentified roles of GIPC3 in potentiating Hh response and melanoma tumorigenesis and suggest that GIPC3 modulation on Hh signaling may be targeted to reduce melanoma growth.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Melanoma/metabolismo , Neoplasias Cutâneas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Aloenxertos , Animais , Carcinogênese , Processos de Crescimento Celular , Regulação Neoplásica da Expressão Gênica , Ouriços/metabolismo , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Proteína GLI1 em Dedos de Zinco/genética , Proteína GLI1 em Dedos de Zinco/metabolismo , Proteína Gli2 com Dedos de Zinco/genética , Proteína Gli2 com Dedos de Zinco/metabolismoRESUMO
Non-traumatic upper extremity amputations are an increasing concern with the rising prevalence of diabetes mellitus. To ascertain the risk factors and mortality rates for these amputations, the demographic information, amputation history, comorbidities and clinical outcomes of 140 patients who underwent non-traumatic upper extremity amputations between 1 January 2004 and 31 October 2017 were studied. Correlations were assessed using Cochran-Armitage chi-squared tests, odds ratios and multivariate binomial logistic regression as appropriate. Diabetes mellitus, coronary artery disease, end-stage renal failure, peripheral arterial disease and prior lower extremity amputation were significant risk factors for multiple upper extremity amputations. One-year, 2-year and 5-year mortality rates were 12%, 15% and 38%, respectively, following first upper extremity amputation. The risk factors for upper extremity amputations correspond with those for lower extremity amputations, comprising mainly diabetes mellitus and its related comorbidities. The mortality rates for non-traumatic upper extremity amputations highlight their significant burden on patients.Level of evidence: III.
