260 research outputs found
Developing an animal model of Dupuytren's disease by orthotopic transplantation of human fibroblasts into athymic rat
Background: Dupuytren's disease (DD) is a slow, progressive fibroproliferative disorder affecting the palms of the hands. The disease is characterized by the formation of collagen rich- cords which gradually shorten by the action of myofibroblasts resulting in finger contractures. It is a disease that is confined to humans, and a major limiting factor in investigating this disorder has been the lack of a faithful animal model that can recapitulate its distinct biology. The aim of this study was to develop such a model by determining if Dupuytren's disease (DD)- and control carpal tunnel (CT)-derived fibroblasts could survive in the forepaw of the nude rats and continue to exhibit the distinct characteristics they display in in vitro cultures. Methods: 1×107 fluorescently labeled DD- and CT-derived fibroblasts were transplanted into the left and right forepaws of nude rats respectively. Cells were tracked at regular intervals for a period of two months by quantifying emitted fluorescent signal using an IVIS imaging system. After a period of 62 days rat forepaw connective tissues were harvested for histology and total RNA was isolated. Human-specific probes were used to perform real time RT-PCR assays to examine the expression patterns of gene products associated with fibrosis in DD. Rat forepaw skin was also harvested to serve as an internal control. Results: Both CT- and DD-derived fibroblasts survived for a period of 62 days, but DD-derived cells showed a significantly greater level of persistent fluorescent signal at the end of this time than did CT-derived cells. mRNA expression levels of α-smooth muscle actin (α-SMA), type I- and type III- collagens were all significantly elevated in the forepaw receiving DD cord-derived fibroblasts in comparison to CT-derived fibroblasts. Masson's trichrome stain confirmed increased collagen deposition in the forepaw that was injected with DD cord-derived fibroblasts. Conclusions: For the first time we describe an animal model for Dupuytren's disease at the orthotopic anatomical location. We further show that gene expression differences between control (CT) and diseased (DD) derived fibroblasts persist when these cells are transplanted to the forepaw of the nude rat. These preliminary findings indicate that, with further refinements, this animal model holds promise as a baseline for investigating novel therapeutic regimens to determine an effective strategy in treating DD
Development of a reactive stroma associated with prostatic intraepithelial neoplasia in EAF2 deficient mice
ELL-associated factor 2 (EAF2) is an androgen-responsive tumor suppressor frequently deleted in advanced prostate cancer that functions as a transcription elongation factor of RNA Pol II through interaction with the ELL family proteins. EAF2 knockout mice on a 129P2/OLA-C57BL/6J background developed late-onset lung adenocarcinoma, hepatocellular carcinoma, B-cell lymphoma and high-grade prostatic intraepithelial neoplasia. In order to further characterize the role of EAF2 in the development of prostatic defects, the effects of EAF2 loss were compared in different murine strains. In the current study, aged EAF2-/- mice on both the C57BL/6J and FVB/NJ backgrounds exhibited mPIN lesions as previously reported on a 129P2/OLA-C57BL/6J background. In contrast to the 129P2/OLA-C57BL/6J mixed genetic background, the mPIN lesions in C57BL/6J and FVB/NJ EAF2-/- mice were associated with stromal defects characteristic of a reactive stroma and a statistically significant increase in prostate microvessel density. Stromal inflammation and increased microvessel density was evident in EAF2-deficient mice on a pure C57BL/6J background at an early age and preceded the development of the histologic epithelial hyperplasia and neoplasia found in the prostates of older EAF2 -/- animals. Mice deficient in EAF2 had an increased recovery rate and a decreased overall response to the effects of androgen deprivation. EAF2 expression in human cancer was significantly down-regulated and microvessel density was significantly increased compared to matched normal prostate tissue; furthermore EAF2 expression was negatively correlated with microvessel density. These results suggest that the EAF2 knockout mouse on the C57BL/6J and FVB/NJ genetic backgrounds provides a model of PIN lesions associated with an altered prostate microvasculature and reactive stromal compartment corresponding to that reported in human prostate tumors. © 2013 Pascal et al
Intravesical Therapy for Non-Muscle-Invasive Bladder Cancer: What Is the Real Impact of Squamous Cell Carcinoma Variant on Oncological Outcomes?
Background and Objectives: To evaluate the oncological impact of squamous cell carcinoma (SCC) variant in patients submitted to intravesical therapy for non-muscle-invasive bladder cancer (NMIBC). Materials and Methods: Between January 2015 and January 2020, patients with conventional urothelial NMIBC (TCC) or urothelial NMIBC with SCC variant (TCC + SCC) and submitted to adjuvant intravesical therapies were collected. Kaplan\u2013Meier analyses targeted disease recurrence and progression. Uni-and multivariable Cox regression analyses were used to test the role of SCC on disease recurrence and/or progression. Results: A total of 32 patients out of 353 had SCC at diagnosis. Recurrence was observed in 42% of TCC and 44% of TCC + SCC patients (p = 0.88), while progression was observed in 12% of both TCC and TCC + SCC patients (p = 0.78). At multivariable Cox regression analyses, the presence of SCC variant was not associated with higher rates of neither recurrence (p = 0.663) nor progression (p = 0.582). Conclusions: We presented data from the largest series on patients with TCC and concomitant SCC histological variant managed with intravesical therapy (BCG or MMC). No significant differences were found in term of recurrence and progression between TCC and TCC + SCC. Despite the limited sample size, this study paves the way for a possible implementation of the use of intravesical BCG and MMC in NMIBC with histological variants
ERCC1-deficient cells and mice are hypersensitive to lipid peroxidation
Lipid peroxidation (LPO) products are relatively stable and abundant metabolites, which accumulate in tissues of mammals with aging, being able to modify all cellular nucleophiles, creating protein and DNA adducts including crosslinks. Here, we used cells and mice deficient in the ERCC1-XPF endonuclease required for nucleotide excision repair and the repair of DNA interstrand crosslinks to ask if specifically LPO-induced DNA damage contributes to loss of cell and tissue homeostasis. Ercc1-/- mouse embryonic fibroblasts were more sensitive than wild-type (WT) cells to the LPO products: 4-hydroxy-2-nonenal (HNE), crotonaldehyde and malondialdehyde. ERCC1-XPF hypomorphic mice were hypersensitive to CCl4 and a diet rich in polyunsaturated fatty acids, two potent inducers of endogenous LPO. To gain insight into the mechanism of how LPO influences DNA repair-deficient cells, we measured the impact of the major endogenous LPO product, HNE, on WT and Ercc1-/- cells. HNE inhibited proliferation, stimulated ROS and LPO formation, induced DNA base damage, strand breaks, error-prone translesion DNA synthesis and cellular senescence much more potently in Ercc1-/- cells than in DNA repair-competent control cells. HNE also deregulated base excision repair and energy production pathways. Our observations that ERCC1-deficient cells and mice are hypersensitive to LPO implicates LPO-induced DNA damage in contributing to cellular demise and tissue degeneration, notably even when the source of LPO is dietary polyunsaturated fats
Desvio fonológico e alterações práxicas orofaciais e do sistema estomatognático
OBJETIVO: verificar, bem como relacionar entre si, o desempenho de crianças com Desvio Fonológico e com Desenvolvimento Fonológico Típico na avaliação do Sistema Estomatognático e em testes de habilidades práxicas orofaciais avaliando suas habilidades práxicas orofaciais. MÉTODOS: amostra constituiu-se de 50 sujeitos, com idades entre quatro e oito anos, com Desvio Fonológico e com Desenvolvimento Fonológico Típico. Avaliou-se a fonologia por meio do instrumento Avaliação Fonológica da Criança e a gravidade do desvio por meio do Percentual de Consoantes Corretas. Posteriormente, aplicou-se a Avaliação do sistema estomatongático e o The Orofacial Praxis Test, para avaliar as habilidades práxicas orofaciais. Os dados foram tabulados e submetidos a tratamento estatístico, considerando-se p<0,05. RESULTADOS: com relação ao sistema estomatongático, observou-se diferença estatística entre os grupos apenas nas tarefas de assobio, contração e vibração de lábios e de língua, apresentando desempenho inferior as crianças com Desvio Fonológico. O mesmo foi observado quanto à postura de língua na sucção. As médias obtidas nas tarefas de habilidades práxicas orofaciais realizadas após Imitação foram melhores que após Solicitação Verbal, para todas as idades. Ainda, as crianças com menor idade apresentaram mais alterações que as crianças maiores, da mesma forma que as crianças com Desvio Fonológico apresentaram mais dificuldades que aquelas sem alterações de fala. CONCLUSÃO: as crianças com Desvio Fonológico apresentaram mais alterações do sistema estomatognático e das habilidades práxicas orofaciais que aquelas com Desenvolvimento Fonológico Típico, havendo melhora no desempenho com o avanço da idade e encontrando-se estas alterações relacionadas com as alterações de fala
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