부산대학교 도서관

The epidermal growth factor receptor (EGFR) T790M mutation, a missense mutation from CpG cytosine to thymine, in non-small cell lung cancer is a drug-resistant mutation induced by the administration of tyrosine kinase inhibitors (TKIs). It is important to detect this mutation with high sensitivity, as effective therapies have been developed for patients with this mutation. We confirmed that cytosine at this mutation point is methylated in various tissues, and the 5-methylcytosine is readily deaminated by hydrolysis and converted to thymine, which is detected as an artifact. We have developed a new method to estimate the artifact in formalin fixed paraffin-embedded (FFPE) specimens by evaluating a mutant ratio of other 5-methylcytosine, enabling sensitive and accurate detection of the T790M mutation.