Enhanced cell death by AdCMV-p53 after irradiation of HeLa cells with 12C6+ ions

ObjectivesTo investigate whether the adenovirus-mediated p53 transfer could enhance the suppression of cervix adenocarcinoma by low-dose (≤2.0 Gy) heavy-ion irradiation.Study designHeLa cells were exposed to C-beam, and then infected with AdCMV-p53 or GFP. P53 expression and cell cycle were detected by flow cytometric analysis. Cell apoptosis was observed under a fluorescent microscope with DAPI staining. The survival fraction was determined by colony forming assay.ResultsDuring the observation, the proportion of p53-positive cells in the C-beam with 80 MOI p53 groups was significantly higher than that in control, C-beam only, 80 MOI p53 only, and C-beam with 40 MOI p53 (p < 0.05). The proportion of cells in G1- or G2-phase in the C-beam with p53 groups was significantly higher than that in the C-beam only groups, or p53 only groups (p < 0.05). The percentage of apoptotic cells for the C-beam with p53 was significantly higher than that for the C-beam only, or p53 only (p < 0.05). The survival fractions for the C-beam with p53 are significantly lower than those for the C-beam only, or p53 only (p < 0.05). SF2 for C-beam with 40 or 80 MOI p53 decreased to ∼10% and ∼4%, respectively, compared with C-beam alone (∼42%).ConclusionsAdenovirus-mediated p53 transfer could enhance the suppression of cervix adenocarcinoma cells by low-dose C-beam irradiation.