Laryngeal tumours with multifactorial etiopathogenesis constitute ∼1% of all body cancers. The imbalance between oxidative and antioxidative systems affects redox-homeostasis. The oxidative stress generated by the continuous formation of reactive oxygen species results in the oxidation of cellular molecules. The present study investigated the protein oxidation levels and the distribution of receptors for advanced glycation end products (RAGE) variants in the risk of laryngeal carcinoma (LC). RAGE gene polymorphisms were determined by restriction endonuclease-based assay in 120 controls and 120 LC patients. Spectrophotometric methods were used to determine oxidant and antioxidant parameters including protein-carbonyl-groups (PCO), advanced-oxidation-protein-products (AOPP), lipid-hydroperoxides (LPH), thiol-fractures, superoxide-dismutase (SOD) activity. The distributions of rs1800624 and rs2070600 genotypes differed non-significantly among the study groups, however, the rs2070600-Ser allele had a higher frequency among the patients. While rs1800624-A allele carriers had higher frequency of perineural and lymphatic invasion, rs2070600-Ser allele frequency was higher in advanced-stage patients and in patients with muscle and perineural invasion. PCO, AOPP, LPH levels, and SOD activity were significantly higher in the patients. According to AUCs all of them are of diagnostic importance, therefore, cut-off values were determined. The analysis of the combined effects of RAGE polymorphisms and the oxidative stress parameters showed that LPH, thiols, and SOD activity differ among RAGE variants. Our results suggest that high levels of serum PCO, AOPP, LPH, and SOD activity and rs2070600-Ser allele may have effects on LC risk individually and both polymorphisms of RAGE may affect the progression of the disease by interacting with the oxidant–antioxidant system.
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