RESUMO
BACKGROUND: PMS2 expression loss was reported in a variety of human. However, its importance has not been fully understood in cervical carcinoma. The aim of this study was to determine the expression of PMS2 in cervical carcinoma and evaluate the significance of mismatch repair gene PMS2 regulated by glycogen synthase kinase 3beta (GSK-3beta) in chemosensitivity. METHODS: We examined PMS2 and phosphorylated GSK-3beta(s9) expression in cervical carcinoma tissues using immunohistochemical staining. Furthermore, we detected PMS2 expression in HeLa cells and evaluate the interaction with GSK-3beta after transfection with GSK-3beta by small interference RNA (siRNA), co-immunoprecipitation and immunoblotting. We also evaluated the effect of PMS2 transfection on HeLa cells' chemosensitivity to cisplatin treatment. RESULTS: We found significant downregulation of PMS2 in cervical carcinoma, which was negatively associated with phosphorylated GSK-3beta (s9). Furthermore, we demonstrated GSK-3beta transfection was able to interact with PMS2 and enhance PMS2 production in HeLa cells, and increased PMS2 production was responsible for enhanced chemosensitivity. CONCLUSIONS: Our results provide the evidence that stabilization of PMS2 production by GSK-3beta was important to improve chemosensitization, indicating the significance of GSK-3beta-related PMS2 downregulation in the development of cervical carcinoma and in developing a potential strategy for chemotherapy.
Assuntos
Adenosina Trifosfatases/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/terapia , Pareamento Incorreto de Bases , Cisplatino/farmacologia , Reparo do DNA , Feminino , Glicogênio Sintase Quinase 3 beta , Células HeLa , Humanos , Imuno-Histoquímica/métodos , Endonuclease PMS2 de Reparo de Erro de Pareamento , Fosforilação , Interferência de RNA , RNA Interferente Pequeno/metabolismo , TransfecçãoRESUMO
OBJECTIVE: To investigate the effect of tranilast on transforming growth factor-beta(2) (TGF-beta(2)) expression in cultured human trabecular meshwork cells. METHODS: TGF-beta(2) expression in cultured 3-5 passage human trabecular meshwork cells was measured by semi-quantitative RT-PCR after treated with 0.0 micro g/ml (control), 12.5, 25.0 and 50.0 mg/L tranilast for 48 h. RESULTS: The value of TGF-beta(2)/G3PDH of cells treated with 12.5, 25.0 and 50.0 mg/L tranilast was 1.85 +/- 0.35, 1.66 +/- 0.42, 1.16 +/- 0.24, respectively. The difference between these treated groups and that of the control group (3.82 +/- 0.56) was statistically significant (q' = 10.77, 11.80, 14.54, P < 0.01), respectively. The value of TGF-beta(2)/G3PDH in the tranilast treated trabecular meshwork cells decreased in a dose-dependent manner. CONCLUSION: Tranilast could inhibit TGF-beta(2) expression in cultured human trabecular meshwork cells. It is worth to study the using of tranilast in the treatment of primary open-angle glaucoma.