The genetic status (wild type or mutant) of the onco-suppressor protein p53 was also considered as a biomarker for similar goals: it was demonstrated on several cell lines of human oral squamous cell carcinoma that 17AAG (a hydrophobic inhibitor of the Hsp90 activity) increased the radiosensitivity of cells with the wild type of p53 rather than mutant [18]. This evidence concerns the gene TP53 and oral cavity squamous cell carcinoma.