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Purpose: Owing to dual functionality of cytosolic glutathione S-transferases (GSTs), they might affect both the development and the progression of renal cell carcinoma (RCC). However, the data on the prognostic value of GST polymorphism in patients with RCC are scarce. Hence, we evaluated the effect of GST gene variants on both the risk of RCC development and the postoperative prognosis in patients with clear cell RCC (ccRCC).Methods: GST genotypes were determined in 305 patients with RCC and 326 matched controls, whereas the overall survival was evaluated in patients with ccRCC only. The presence of GSTM1:ASK1 protein-protein interaction in ccRCC tissue samples was analyzed by methods of immunoprecipitation and immunoblot.Results: We noted an increased risk of RCC development in carriers of GSTM1-null and GSTP1-variant genotype (P<0.05). On the contrary, survival analysis indicated shorter overall survival for patients with ccRCC with GSTM1-active genotype (P = 0.026). Furthermore, patients with ccRCC with GSTM1-active genotype had significantly higher hazard ratio (P<0.05), in analyzed regression models, compared with the carriers of GSTM1-null genotype. Finally, the presence of GSTM1:ASK1 protein-protein interaction was found in all RCC tissue samples studied.Conclusions: Carriers of GSTM1-null and GSTP1-variant genotypes are in increased risk of RCC development. On the contrary, GSTM1-null genotype is associated with favorable postoperative prognosis in ccRCC. The possible molecular mechanism underlying the role of GSTM1 protein in RCC progression might be the presence of GSTM1:ASK1 protein-protein interaction. Hence, determination of GSTM1-genotype might serve as a valuable indicator in both RCC risk assessment and postoperative prognosis. [ABSTRACT FROM AUTHOR]

Purpose: Oxidative stress is recognized as an important factor in progressive myoclonus epilepsy (PME). Genetic polymorphism of glutathione S-transferases (GSTs), which are involved in both protection from oxidative damage and detoxification, might alter the capacity for protecting tissues from exogenous and endogenous oxidants. We aimed to assess a possible association between GST polymorphism and PME, as well as, correlation between GST genotypes and oxidative phenotype in PME patients.Methods: GSTA1, GSTM1, GSTP1 and GSTT1 genotypes were determined in 26 patients with PME and 66 controls. Byproducts of protein oxidative damage (thiol groups (P-SH) and nitrotyrosine), superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities were determined.Results: The frequency of GSTA1, GSTM1 and GSTP1 genotypes was not significantly different between PME patients and controls, while individuals with GSTT1-null genotype were at 5.44-fold higher risk of PME than carriers of GSTT1-active genotype. Moreover, significant risk of PME was obtained in carriers of both GSTT1-null and GSTM1-null genotypes. Carriers of combined GSTA1- active and GSTT1-null genotype were at highest, 7.55-fold increased risk of PME. Byproducts of protein damage did not reach statistical significance, while SOD and GPX activities were significantly higher in PME patients then in controls. When stratified according to GST genotype, P-SH groups were significantly lower only in patients with GSTT1-null genotype in comparison to carriers of active genotype. Only SOD activity was increased in GSTT1-null when compared to corresponding active genotype.Conclusions: GSTT1-null genotype might be associated with the increased risk and enhanced susceptibility to oxidative stress in PME patients. [ABSTRACT FROM AUTHOR]

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Abstract: Background: Although the majority of previous findings unequivocally confirmed the existence of systemic oxidative stress in chronic heart failure (CHF) patients, data on prognostic potential of biomarkers of oxidative lipid and protein damage are limited. We aimed to address the relation of oxidative stress markers to severity and prognosis in CHF secondary to ischemic cardiomyopathy. Methods and Results: Plasma malondialdehyde (MDA), protein thiol groups (P-SH), reactive carbonyl derivatives (RCD), together with glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities were determined in 120 CHF patients and 69 healthy controls. Increased lipid peroxidation (MDA) and oxidation of plasma proteins (RCD; P-SH) s well as downregulated GSH-Px activity were found in CHF patients compared with controls. Significant correlation was obtained only for RCD content and remodeling indices (LVEDV: r = 0.469, P = .008; LVESV: r = 0.452; P = .011). Cox regression analysis demonstrated only MDA (HR = 3.33; CI: 1.55–7.12; P = .002) as independent predictor of death, whereas SOD was associated with unstable angina pectoris (HR = 2.09; CI: 1.16–3.78; P = .011). Conclusions: In the course of CHF progression, carbonyl stress is implicated in the LV remodeling. Malondialdehyde level might be a useful parameter for monitoring and planning management of CHF patients. [Copyright &y& Elsevier]

Abstract: Purpose: To get more insight into molecular mechanisms underlying oxidative stress and its role in different types of seizure, in this study, oxidative byproducts of proteins, lipids and DNA, as well as, antioxidant enzyme activities were studied in adult patients with epilepsy. Methods: Study was performed in 60 patients with epilepsy and in 25 healthy controls. Plasma protein reactive carbonyl derivatives (RCD) and protein thiol groups (P-SH), byproducts of oxidative protein damage, as well as antioxidant enzyme activities, superoxide dismutase (SOD) and glutathione peroxidase (GPX) were studied spectrophotometrically. Urinary 8-epi-prostaglandin F2α (8-epi-PGF2α) and 8-hydroxy-2′-deoxyguanosine (8-OHdG), representative byproducts of lipid and DNA oxidative damage, respectively, were determined by enzyme immunoassay. Results: RCD levels were significantly increased (p =0.001), while P-SH content was decreased in patients with first seizure (p =0.052) compared to controls, independently of the seizure type. Urinary 8-epi-PGF2α and 8-OHdG were significantly increased in patients with epilepsy (p =0.001 and p =0.001). Rise in 8-epi-PGF2α was more pronounced in patients with generalized tonic–clonic seizure (GTCS) compared to those with partial seizure (PS). Both SOD and GPX activity were significantly increased in epileptic patients compared to controls (p =0.001 and p =0.001), but only SOD activity was significantly higher in patients with GTCS than in those with PS. Conclusions: Data on enhanced protein, lipid and DNA oxidation, together with upregulated antioxidant enzyme activities, confirm the existence of systemic oxidative stress in patients with epilepsy. It might be speculated that post-translational modification to existing functional proteins, particularly alterations to ion channels, might be at least partially responsible for acute early changes in neuronal networks. [Copyright &y& Elsevier]

Upregulated glutathione S-transferase P1 (GSTP1) plays an important role in the resistance to apoptosis in transitional cell carcinoma (TCC) of the urinary bladder (UB) and represents a potential target for chemotherapeutic agents. Our aim was to perform a systematic investigation of a glutathione S-transferase (GST) isoenzyme profile (GSTM, GSTP1, and GSTT1) in the upper urinary tract (UUT) TCC and compare it with the GST isoenzyme pattern of the UB TCC and normal urothelium. We examined GST activity spectrophotometrically by using substrates for the overall GST activity, GSTP1, and GSTT1 in the cytosolic fraction. GSTP1 and GSTM expression was analyzed by Western blotting. The results obtained have shown that the overall GST activity was significantly higher in UUT TCC in comparison with urothelium (P <0.001), which gradually increases with tumor grade (P <0.05). The mean GSTP1 and GSTT1 activities in UUT TCC were 2- and 3.6-fold higher, respectively, than in the normal urothelium (P <0.001), and these values did not differ significantly from activities found in the UB TCC. GSTM was expressed in 42% of the UUT TCC and 50% of the UB TCC specimens. The level of GSTM expression was slightly increased in the UUT TCC specimens in comparison with normal urothelium (P >0.05). We conclude that 3 major cytosolic GST classes, GSTM, GSTP1, and GSTT1, are expressed in the UUT TCC. The isoenzyme profile of GST in the UUT TCC is similar to that observed in the UB TCC; it shows essentially the same alteration of the GST phenotype in the course of cancerization. The association of GSTT1 and GSTP1 upregulation with the malignant phenotype of the UUT TCC might result in resistances to both chemotherapy and apoptosis. [Copyright &y& Elsevier]