Abstract
In the present study, CCD32SK diploid normal human fibroblasts were transiently transfected with short interfering RNA (siRNA) specific for human p53 (CCD/p53i). There was a small increase in the frequency of centrosome amplification in CCD/p53i cells without hyperthermia. In contrast, CCD/p53i cells after hyperthermia showed a marked increase in abnormal nuclear shapes and pronounced amplification of centrosomes. At 12 h after irradiation, irradiated CCD/p53i cells were arrested in G2 phase. On laser scanning cytometry, abnormal mitosis with amplified centrosomes was frequently observed in the accumulating G2/M population at 48 h after hyperthermia.
In the present study, we found that siRNA-mediated silencing of p53 in normal human fibroblasts, together with DNA damage by hyperthermia, efficiently induces centrosome amplification and nuclear fragmentation, but these phenomena were not observed with either siRNA-mediated silencing of p53 or irradiation alone.
