Evidence that Individual Variations in TP53 and CDKN1A Protein Responsiveness are Related to Inherent Radiation Sensitivity

Abstract Alsbeih, G., Torres, M., Al-Harbi, N. and Al-Buhairi, M. Evidence that Individual Variations in TP53 and CDKN1A Protein Responsiveness are Related to Inherent Radiation Sensitivity. Radiat. Res. 167, 58–65 (2007). We tested the hypothesis that individual variations in the induction of the TP53 tumor suppressor protein by radiation are related to inherent radiosensitivity. Thirty-two fibroblast cell strains were examined. Radiosensitivity was measured by a clonogenic survival assay. The induction of TP53 and its transcriptionally activated CDKN1A (p21) protein were studied by Western blotting 3 h after a single dose of 5 Gy. The relative cell culture age, as determined by the colony size distribution, was studied as a confounding factor. Survival curves showed wide range of radiosensitivity. The surviving fraction at 2 Gy (SF2) ranged between 0.02 and 0.49 (mean = 0.29, SD = 0.13). TP53 induction ranged between 1.28 and 2.34 (mean = 1.80, SD = 0.31). CDKN1A showed a wider induction (1.09–4.05, mea...