RESUMO
Alteration of podocyte behavior is critically involved in the development and progression of many forms of human glomerular diseases. The molecular mechanisms that control podocyte behavior, however, are not well understood. Here, we investigated the role of Kindlin-2, a component of cell-matrix adhesions, in podocyte behavior in vivo Ablation of Kindlin-2 in podocytes resulted in alteration of actin cytoskeletal organization, reduction of the levels of slit diaphragm proteins, effacement of podocyte foot processes, and ultimately massive proteinuria and death due to kidney failure. Through proteomic analyses and in vitro coimmunoprecipitation experiments, we identified Rho GDP-dissociation inhibitor α (RhoGDIα) as a Kindlin-2-associated protein. Loss of Kindlin-2 in podocytes significantly reduced the expression of RhoGDIα and resulted in the dissociation of Rac1 from RhoGDIα, leading to Rac1 hyperactivation and increased motility of podocytes. Inhibition of Rac1 activation effectively suppressed podocyte motility and alleviated the podocyte defects and proteinuria induced by the loss of Kindlin-2 in vivo Our results identify a novel Kindlin-2-RhoGDIα-Rac1 signaling axis that is critical for regulation of podocyte structure and function in vivo and provide evidence that it may serve as a useful target for therapeutic control of podocyte injury and associated glomerular diseases.
Assuntos
Proteínas do Citoesqueleto/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Musculares/metabolismo , Proteínas de Neoplasias/metabolismo , Neuropeptídeos/metabolismo , Podócitos/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Inibidor alfa de Dissociação do Nucleotídeo Guanina rho/metabolismo , Albuminúria/metabolismo , Animais , Apoptose , Movimento Celular , Creatinina/análise , Proteínas do Citoesqueleto/genética , Progressão da Doença , Feminino , Fibrose , Genótipo , Humanos , Glomérulos Renais/patologia , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Proteínas Musculares/genética , Proteínas de Neoplasias/genética , RNA Interferente Pequeno/metabolismo , Insuficiência Renal/patologia , Transdução de SinaisRESUMO
Differentiated thyroid cancer is the most frequently diagnosed endocrine tumor. While differentiated thyroid cancers often respond to initial treatment, little is known about the differences in circulating immune cells amongst patients who respond differently. A prospective study of 39 patients with differentiated thyroid cancer was conducted. Serum thyroglobulin levels and thyroid and immunological functions were tested before and after radioactive iodine treatment (RAIT). Efficacy assessments were performed 6 to 12 months after radioactive iodine treatment. Most patients showed an excellent response to radioactive iodine treatment. Before radioactive iodine treatment, the excellent response group had considerably fewer circulating CD4+ T cell subsets than the non-excellent response group. Both the excellent response and non-excellent response groups had considerably lower circulating CD4+ T lymphocyte subsets 30 days after radioactive iodine treatment, but those of the excellent response group were still lower than those of the non-excellent response group. All circulating CD4+ T cell subsets in the excellent response group rose by varying degrees by the 90th day, but only Treg cell amounts increased in the non-excellent response group. Interestingly, in the non-excellent response group, we noticed a steady drop in Th1 cells. However, the bulk of circulating CD4+ T cell subsets between the two groups did not differ appreciably by the 90th day. Finally, we discovered that CD4+ T cell subsets had strong predictive potential, and we thus developed high-predictive-performance models that deliver more dependable prognostic information. In conclusion, in individuals with differentiated thyroid cancer, there is great variation in circulating immune cells, resulting in distinct treatment outcomes. Low absolute CD4+ T cell counts is linked to improved clinical outcomes as well as stronger adaptive and resilience capacities.
Assuntos
Adenocarcinoma , Neoplasias da Glândula Tireoide , Adenocarcinoma/tratamento farmacológico , Linfócitos T CD4-Positivos/patologia , Humanos , Radioisótopos do Iodo/uso terapêutico , Prognóstico , Estudos Prospectivos , Subpopulações de Linfócitos T/patologia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/radioterapiaRESUMO
The effects of total thyroidectomy or radioactive iodine therapy on immune activation and suppression of the tumor microenvironment remain unknown. We aimed to investigate the effects of these treatments on the immune function in patients with differentiated thyroid carcinoma (DTC). Our cohort included 45 patients with DTC treated with total thyroidectomy and radioactive iodine therapy (RAIT). Immune function tests were performed by flow cytometry at 0, 30, and 90 days post-RAIT. Both the percentage and absolute number of circulating regulatory T cells were significantly lower in the postoperative DTC compared to the healthy controls. Notably, the absolute number of multiple lymphocyte subgroups significantly decreased at 30 days post-RAIT compared to those pre-RAIT. The absolute counts of these lymphocytes were recovered at 90 days post-RAIT, but not at pre-RAIT levels. Additionally, the Th17 cell percentage before RAIT was positively correlated with thyroglobulin (Tg) levels after RAIT. The tumor burden might contribute to increased levels of circulating Tregs. In conclusion, RAIT caused transient radiation damage in patients with DTC and the percentage of Th17 cells before RAIT could be a significant predictor of poor prognosis in patients with DTC.
Assuntos
Adenocarcinoma , Neoplasias da Glândula Tireoide , Adenocarcinoma/cirurgia , Humanos , Imunidade , Radioisótopos do Iodo/uso terapêutico , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Microambiente TumoralRESUMO
OBJECTIVE: Graves' disease (GD) is one of the most common autoimmune conditions, but the mechanisms underlying the associated induction of autoimmunity are not known. We explored the role of peripheral lymphocyte subpopulations in disease pathogenesis. METHODS: In total, 32 patients and 40 age- and sex-matched healthy controls were recruited in this study. Peripheral levels of T, B, NK, CD4+ T, CD8+ T, Th1, Th2, Th17, and Treg cells were measured using flow cytometry. For all patients, we compared all lymphocyte subpopulations between GD patients and healthy controls. Changes in patient lymphocyte subsets were compared before and after treatment. RESULTS: The absolute numbers of circulating Th17 cells (0.45 ± 1.16, p > 0.05) between GD patients and healthy controls were not significantly different. However, the percentage of Th17 cells was significantly increased (0.25 ± 0.11, p < 0.05). The absolute numbers and percentages of circulating Tregs in GD patients were significantly decreased compared with those in healthy participants (11.61 ± 2.75, p < 0.05). There was a significant difference in Treg absolute numbers between the untreated and drug-treated groups. Furthermore, we found that the Treg percentage in untreated patients (mean=4.78) was not significantly different from that in the drug-treated group (mean=4.81). In addition, circulating Treg absolute numbers in GD patients with exophthalmos were significantly lower than those in GD patients without exophthalmos (9.96 ± 4.16, p < 0.05). A similar trend was observed in GD patients with weight loss (11.97 ± 3.28, p < 0.05). CONCLUSION: GD pathogenesis was associated with a lower Treg population and an increased Th17/Treg ratio (T helper cell 17/ regulatory T cells). Th17 cells in this study were not related to the disease. Furthermore, anti-thyroid drug therapy improved immune-mediated system disorders. Finally, we found lower absolute numbers of circulating Tregs in GD patients with certain positive signs, such as exophthalmos and/or weight loss. Thus, immune changes are correlated with partial clinical manifestations.
Assuntos
Doença de Graves , Linfócitos T Reguladores , Doença de Graves/diagnóstico , Doença de Graves/tratamento farmacológico , Humanos , Contagem de Linfócitos , Células Th17 , Redução de PesoRESUMO
This paper presents improvements to the conventional Topology Representing Network to build more appropriate topology relationships. Based on this improved Topology Representing Network, we propose a novel method for online dimensionality reduction that integrates the improved Topology Representing Network and Radial Basis Function Network. This method can find meaningful low-dimensional feature structures embedded in high-dimensional original data space, process nonlinear embedded manifolds, and map the new data online. Furthermore, this method can deal with large datasets for the benefit of improved Topology Representing Network. Experiments illustrate the effectiveness of the proposed method.