PKC isoform selectivity and radiation-induced apoptosis of HepG2 cells / 南方医科大学学报

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the expressions of protein kinase C (PKC) isoforms in X-ray-exposed HepG2 cells and identify the PKC isoforms that induce radioresistance in HepG2 cells.</p><p><b>METHODS</b>Cultured HepG2 cells were divided into control group and 6 Gy radiation group for corresponding treatments. The fluorescence intensity (FI) and the percentage of positive cells were determined using flow cytometry.</p><p><b>RESULTS</b>The FI of PKCalpha and PKCdelta were 2.28 and 5.05 in the radiation group, respectively, significantly higher than those in the control group (P<0.05). The percentages of PKCalpha- and PKCdelta -positive cells were significantly higher in the radiation group than in the control group (P<0.05). The FI and the percentages of PKC zeta, gamma, epsilon, zeta positive cells were rather low and showed no significant differences between the two groups (P>0.05); PKCbeta expression was not detected in the two groups of cells. The apoptosis rates of the control and radiation groups were 1.73% and 20.90%, respectively.</p><p><b>CONCLUSION</b>PKCalpha and PKCdelta may be involved in protecting HepG2 cells from radiation-induced apoptosis.</p>