RESUMO
Objective: A pure nucleotide pool is essential for correct DNA replication in addition to the prevention of mutagenesis and abnormalities in a living cell. Inosine triphosphatase [ITPase] is a critical enzyme for the removal of deaminated rough purine nucleotides such as inosine from the nucleotide pool. It has been shown that abnormal function and expression of the ITPA gene is followed by an increased substitution mutation rate in the genome. This study compares the ITPA gene expression level between human adenocarcinoma tumors and their normal marginal tissues
Method: We examined ITPA gene expression in 24 pairs of gastric adenocarcinoma tumors and their normal adjacent tissues by quantitative real-time PCR
Result: There was reduced ITPA gene expression in tumor tissues compared with the adjacent normal tissues. The decline in ITPA gene expression was more significant in the higher grade samples
Conclusion: ITPA is involved in omitting deaminated purines from the nucleotide pool. Therefore its abnormal function increases the frequency of mutations and causes higher genomic instability. Our data suggest that lower expression of ITPA can be considered a risk factor for the development and progression of gastric cancer