In order to determine the mutation and mRNA expression changes of the ATM gene in HGC, we performed analyses by denaturing high-performance liquid chromatography (DHPLC), DNA sequencing and RT-PCR technique on 13 human gastric tumor cell lines and 30 cases of fresh tumor specimens matched normal tissue.
We analyzed stomach tumors with microsatellite instability (MSI) for frameshift mutations in several potential targets of the mutator phenotype involved in DNA damage-response pathways, such as the ataxia telangiectasia mutated protein-related protein (ATR)-CHK1-Cdc25c pathway, and DNA repair.