[Development of TP53-Targeted Treatment in Esophageal Squamous Cell Carcinoma Using Cancer Genomic Profiling Test]

Recently, the interest in cancer genomic medicine has increased, owing to the powerful and cost-effective technology of next-generation sequencing(NGS), which allows rapid identification of a large number of gene mutations. TP53 mutations are frequently found in solid cancers, especially in esophageal squamous cell carcinoma(ESCC), wherein the frequency of TP53 mutation is considered to be 90% or more. However, there is no clinical targeted therapy as yet utilizing TP53. Here, we aimed to characterize TP53 mutations associated with ESCC, in order to assess its feasibility as a therapeutic target. We extracted DNA and RNA from specimens of ESCC patients and analyzed them using NGS, which revealed different TP53 mutations. Based on previous reports, it is considered that different TP53 mutations lead to different functions of the protein, and subsequently account for varied prognosis in squamous cell carcinoma of the head and neck. We also performed cell viability assay using ESCC cell lines with different TP53 mutations and 2 kinds of p53-targeted drug and found differences in the growth inhibition of the cell lines. Although individual treatment can be determined depending on the type of TP53 mutation, it would be necessary to further examine the interaction of TP53 with other genes to determine its therapeutic efficacy as a target.