Disturbances in Nitric Oxide Cycle and Related Molecular Pathways in Clear Cell Renal Cell Carcinoma.

It is important to note that maintaining adequate levels of nitric oxide (NO), the turnover, and the oxidation level of nitrogen are essential for the optimal progression of cellular processes, and alterations in the NO cycle indicate a crucial step in the onset and progression of multiple diseases. Cellular accumulation of NO and reactive nitrogen species in many types of tumour cells is expressed by an increased susceptibility to oxidative stress in the tumour microenvironment. Clear cell renal cell carcinoma (ccRCC) is a progressive metabolic disease in which tumour cells can adapt to metabolic reprogramming to enhance NO production in the tumour space. Understanding the factors governing NO biosynthesis metabolites in ccRCC represents a relevant, valuable approach to studying NO-based anticancer therapy. Exploring the molecular processes mediated by NO, related disturbances in molecular pathways, and NO-mediated signalling pathways in ccRCC could have significant therapeutic implications in managing and treating this condition.

Cellular Response against Oxidative Stress, a Novel Insight into Lupus Nephritis Pathogenesis.

The interaction of reactive oxygen species (ROS) with lipids, proteins, nucleic acids and hydrocarbonates promotes acute and chronic tissue damage, mediates immunomodulation and triggers autoimmunity in systemic lupus erythematous (SLE) patients. The aim of the study was to determine the pathophysiological mechanisms of the oxidative stress-related damage and molecular mechanisms to counteract oxidative stimuli in lupus nephritis. Our study included 38 SLE patients with lupus nephritis (LN group), 44 SLE patients without renal impairment (non-LN group) and 40 healthy volunteers as control group. In the present paper, we evaluated serum lipid peroxidation, DNA oxidation, oxidized proteins, carbohydrate oxidation, and endogenous protective systems. We detected defective DNA repair mechanisms via 8-oxoguanine-DNA-glycosylase (OGG1), the reduced regulatory effect of soluble receptor for advanced glycation end products (sRAGE) in the activation of AGE-RAGE axis, low levels of thiols, disulphide bonds formation and high nitrotyrosination in lupus nephritis. All these data help us to identify more molecular mechanisms to counteract oxidative stress in LN that could permit a more precise assessment of disease prognosis, as well as developing new therapeutic targets.

Sialoglyco-Conjugate Abnormalities, IL-6 Trans-Signaling and Anti-Ganglioside Immune Response-Potential Interferences in Lupus Nephritis Pathogenesis.

We have investigated glycoconjugates sialization profile, endogen synthesis rate of antiganglioside antibodies (AGA), IL-6 signaling pathways correlated with activity disease in systemic lupus erythematous (SLE) and lupus nephritis (LN). MATERIAL AND METHODS: A case-control study was developed and included 109 patients with SLE with or without renal impairment, 32 patients with IgA nephropathy and 60 healthy volunteers, clinically and paraclinically monitored. The following parameters were evaluated in volunteers serum: total sialic acid (TSA), orosomucoids, lipid bound sialic acid (LSA), interleukin-6 (IL-6), soluble factors IL-6R, gp130, anti -GM1, -GM2, -GM3, -GD1a, -GD1b, -GT1b, -GQ1b antigangliosides antibodies of IgG and IgM type. RESULTS: Experimental data analysis showed: increase in synthesis rhythm of sialoglyco-conjugated in SLE (TSA increased in SLE and LN compared to control), accelerated catabolism of LSA in LN (LSA/TSA ratio was higher in SLE and LN than in control group), overexpression of IL-6 mediated trans-signaling (sIL-6R/sgp 130 ratio was subunit in SLE and IgA nephropathy and superunit in LN), large AGA profile synthesis of IgM isotype (over 45.1% in SLE and over 20.7% in LN). CONCLUSIONS: Hypersialization, accelerated glycosphingolipids degradation, IL-6 trans-signaling amplify and AGA pattern could represent essential mechanisms in LN pathogenesis.

Posttranslational Modifications Pattern in Clear Cell Renal Cell Carcinoma.

Posttranslational modifications are dynamic enzymatic-mediated processes, regulated in time and space, associated with cancer development. We aimed to evaluate the significance of posttranslational modifications in the pathogenesis of clear cell renal cell carcinoma. The authors developed a prospective, observational study during a period of three years and included 55 patients with localized renal cell carcinoma and 30 heathy subjects. Glycosylation, nitration and carbonylation, thiol-disulfide homeostasis, methylation, phosphorylation and proteolytic cleavage were evaluated in the serum of the evaluated subjects in the present study. Our results showed some characteristics for early ccRCC: high production of cytokines, substrate hypersialylation, induced nitrosative and carbonylic stress, arginine hypermethylation, thiol/disulfide homeostasis (TDH) alteration, the regulatory role of soluble receptors (sRAGE, sIL-6R) in RAGE and IL-6 signaling, the modulatory effect of TK-1and TuM2-PK in controlling the level of phosphometabolites in neoplastic cells. These data could be the initial point for development of a panel of biomarkers such as total sialic acid, orosomucoids, nitrotyrosine, carbonylic metabolites, ADMA, SDMA, and thiol-disulfide equilibrium for early diagnosis of ccRCC. Moreover, they could be considered a specific disease PTM signature which underlines the transition from early to advanced stages in this neoplasia, and of a therapeutic target in kidney oncogenesis.