Relative amounts of sugar structures of proteins with molecular masses above 30 kDa were determined by ELISA-like test with biotinylated lectins: MAA (Maackia amurensis), SNA (Sambucus nigra), and monoclonal antibodies anti-sialyl Lewis(a/x) Higher expression of all examined structures Tipifarnib leukemia was revealed in cancer tissues. Significant increases were observed for sialic acid linked alpha 2-3 in cancer tissues when compared to healthy ones and also among intermediate and healthy tissues. The sialic acid linked alpha 2-6 and sialyl Lewis(x) structures were significantly increased in cancerous cells when compared to normal and intermediate renal tissue. In case of sialyl Lewis(a) antigen, a significant difference was discovered between normal and intermediate tissue.
Our results confirm that the examined Lewis antigens can be involved in tumor development. Their increase in cancer tissues can suggest their specific role in the process.
In order to characterize the possible mechanism(s) of cytotoxicity of a neuroleptic agent 6,7-dinitrodihydro-quinoxaline-2,3-dione (DNQX) we examined the redox properties of DNQX, and its mononitro- (NQX) and denitro- (QX) derivatives. The irreversible electrochemical reduction of the nitro groups of DNQX was characterized by the reduction peak potentials (E-p,E-7) of -0.43 V and -0.72 V vs. Ag/AgCl at pH 7.0, whereas NQX was reduced at E-p,E-7 = -0.67 V. The reactivities of DNQX and NQX towards the single-electron transferring enzymes NADPH:cytochrome P-450 reductase and NADPH:adrenodoxin reductase/adrenodoxin complex were similar to those of model nitrobenzenes with the single-electron reduction potential (E-7(1)) values of -0.
29 V – -0.42 V. DNQX and NQX also acted Brefeldin_A as substrates for two-electron transferring mammalian NAD(P)H:quinone oxidoreductase (DT-diaphorase). The cytotoxicity of DNQX in bovine leukemia virus-transformed lamb kidney fibroblasts (line FLK) was prevented by antioxidants and an inhibitor of NQO1, dicoumarol, and was enhanced by the prooxidant alkylating agent 1,3-bis(2-chloromethyl)-1-nitrosourea. A comparison with model nitrobenzene compounds shows that the cytotoxicity of DNQX and NQX reasonably agrees with the ease of their electrochemical reduction, and/or their reactivities towards the used enzymatic single-electron reducing systems. Thus, our data imply that the cytotoxicity of DNQX in FLK cells is exerted mainly through oxidative stress.
The evolutionarily conserved proteins forming sister chromatid cohesion complex are also involved in the regulation of gene transcription. Ponatinib The participation of SA2p (mammalian ortholog of yeast Irr1p, associated with the core of the complex) in the regulation of transcription is already described. Here we analyzed microarray profiles of gene expression of a Saccharomyces cerevisiae irr1-1/IRR7 heterozygous diploid strain. We report that expression of 33 genes is affected by the presence of the mutated Irr1-1p and identify those genes.