RESUMEN
Type II endometrial carcinomas (ECs) are estrogen independent, poorly differentiated tumors that behave in an aggressive manner. As TP53 mutation and CDH1 inactivation occur in 80% of human endometrial type II carcinomas, we hypothesized that mouse uteri lacking both Trp53 and Cdh1 would exhibit a phenotype indicative of neoplastic transformation. Mice with conditional ablation of Cdh1 and Trp53 (Cdh1(d/d)Trp53(d/d)) clearly demonstrate architectural features characteristic of type II ECs, including focal areas of papillary differentiation, protruding cytoplasm into the lumen (hobnailing) and severe nuclear atypia at 6 months of age. Further, Cdh1(d/d)Trp53(d/d) tumors in 12-month-old mice were highly aggressive, and metastasized to nearby and distant organs within the peritoneal cavity, such as abdominal lymph nodes, mesentery and peri-intestinal adipose tissues, demonstrating that tumorigenesis in this model proceeds through the universally recognized morphological intermediates associated with type II endometrial neoplasia. We also observed abundant cell proliferation and complex angiogenesis in the uteri of Cdh1(d/d)Trp53(d/d) mice. Our microarray analysis found that most of the genes differentially regulated in the uteri of Cdh1(d/d)Trp53(d/d) mice were involved in inflammatory responses. CD163 and Arg1, markers for tumor-associated macrophages, were also detected and increased in the uteri of Cdh1(d/d)Trp53(d/d) mice, suggesting that an inflammatory tumor microenvironment with immune cell recruitment is augmenting tumor development in Cdh1(d/d)Trp53(d/d) uteri. Further, inflammatory mediators secreted from CDH1-negative, TP53 mutant endometrial cancer cells induced normal macrophages to express inflammatory-related genes through activation of nuclear factor-κB signaling. These results indicate that absence of CDH1 and TP53 in endometrial cells initiates chronic inflammation, promotes tumor microenvironment development following the recruitment of macrophages and promotes aggressive ECs.
Asunto(s)
Proteínas Cdh1/genética , Neoplasias Endometriales/genética , Inflamación/genética , Macrófagos/inmunología , Proteína p53 Supresora de Tumor/genética , Animales , Antígenos CD/genética , Antígenos de Diferenciación Mielomonocítica/genética , Arginasa/genética , Línea Celular , Proliferación Celular/genética , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Neoplasias Endometriales/patología , Femenino , Humanos , Inflamación/inmunología , Inflamación/patología , Ratones , Ratones Noqueados , FN-kappa B/metabolismo , Neovascularización Patológica/genética , Receptores de Superficie Celular/genética , Microambiente Tumoral/inmunología , Útero/citología , Útero/patologíaRESUMEN
We previously characterized the link between WNT7A and the progression of ovarian cancer. Other groups have identified FGF1 as a relevant risk factor in ovarian cancer. Here, we show a linkage between these two signaling pathways that may be exploited to improve treatment and prognosis of patients with ovarian cancer. High expression of WNT7A and FGF1 are correlated in ovarian carcinomas and poor overall patient survival. A chromatin immunoprecipitation assay demonstrated that WNT7A/ß-catenin signaling directly regulates FGF1 expression via TCF binding elements in the FGF1-1C promoter locus. In vitro gene manipulation studies revealed that FGF1 is sufficient to drive the tumor-promoting effects of WNT7A. In vivo xenograft studies confirmed that the stable overexpression of WNT7A or FGF1 induced a significant increase in tumor incidence, whereas FGF1 knockdown in WNT7A overexpressing cells caused a significant reduction in tumor size. Niclosamide most efficiently abrogated WNT7A/ß-catenin signaling in our model, inhibited ß-catenin transcriptional activity and cell viability, and increased cell death. Furthermore, niclosamide decreased cell migration following an increase in E-cadherin subsequent to decreased levels of SLUG. The effects of niclosamide on cell functions were more potent in WNT7A-overexpressing cells. Oral niclosamide inhibited tumor growth and progression in an intraperitoneal xenograft mouse model representative of human ovarian cancer. Collectively, these results indicate that FGF1 is a direct downstream target of WNT7A/ß-catenin signaling and this pathway has potential as a therapeutic target in ovarian cancer. Moreover, niclosamide is a promising inhibitor of this pathway and may have clinical relevance.
Asunto(s)
Resistencia a Antineoplásicos , Factor 1 de Crecimiento de Fibroblastos/genética , Niclosamida/farmacología , Neoplasias Ováricas , Proteínas Wnt/fisiología , beta Catenina/fisiología , Animales , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Células Cultivadas , Progresión de la Enfermedad , Resistencia a Antineoplásicos/genética , Femenino , Factor 1 de Crecimiento de Fibroblastos/metabolismo , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Vía de Señalización Wnt/fisiologíaRESUMEN
Human platelets, prelabelled with [3H]-adenine in vitro, were aggregated biphasically by bovine fibrinogen/factor VIII, and the amounts and specific radioactivity of ADP and ATP as well as the radioactivity of ATP, ADP, AMP, IMP and hypoxanthine + inosine were determined intracellularly and extracellularly. During the second phase of aggregation, ATP and ADP were released (50% of total) with a specific radioactivity 15-20 times lower than that of the ATP and ADP retained in the cells. The specific radioactivity of the ATP and ADP in the cells increased during release. Radioactive ATP was converted to radioactive hypoxanthine during release. These findings correlated well with those obtained with collagen, and indicate that bovine factor VIII induces the platelet release reaction whereby the storage (non-metabolic) pool of ATP and ADP is released while the metabolic pool is retained.