<b>Introduction:</b> Colorectal cancer (CRC), despite intensive research on the improvement of diagnosis and treatment, is still the second most deadly cancer in Poland in terms of mortality. One of the factors predisposing to a higher risk of CRC may be the individual differences in the effectiveness of proteins responsible for the metabolism of xenobiotics - it seems that the removal of potentially harmful exogenous substances significantly reduces the risk of carcinogenesis. </br></br> <b>Aim:</b> In this work, we analyzed the effect of polymorphisms of genes responsible for metabolizing xenobiotics on the risk of CRC - rs72554606 polymorphism of N AT 1 gene, rs1799930 polymorphism of N AT 2 gene and rs1799814 polymorphism of CYP1A1 gene, as well as the level of expression of these genes. </br></br> <b> Conclusions:</b> The results indicate that the GC genotype for N AT 1 and the GA genotype for CYP1A1 may increase the risk of CRC, and in those already diagnosed with colorectal cancer, the expression level of NAT1 is significantly lower than in the control. We believe that these factors may have potential prognostic and diagnostic significance in the treatment of CRC.
Keywords: CYP1A1; NIL1; NIL2; colorectal cancer; gene expression; gene polymorphism; xenobiotic metabolism.