[PKC isoform selectivity and radiation-induced apoptosis of HepG2 cells].
OBJECTIVE
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.


METHODS
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.


RESULTS
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.


CONCLUSIONS
PKCalpha and PKCdelta may be involved in protecting HepG2 cells from radiation-induced apoptosis.
Xia
Qiong
Q
Nanfang Hospital, Southern Medical University, Guangzhou 510515, China. xiaqiong@fimmu.com
Li
Chuan-gang
CG
Sun
Ai-min
AM
Zhang
Xue-lin
XL
D017209:Apoptosis / Q000502:physiology / Q000528:radiation effects*; D056945:Hep G2 Cells; D006801:Humans; D007527:Isoenzymes / Q000145:classification / Q000378:metabolism; D051571:Protein Kinase C-alpha / Q000378:metabolism*; D051745:Protein Kinase C-delta / Q000378:metabolism*; D011836:Radiation Tolerance; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology
D007527:Isoenzymes; D051571:Protein Kinase C-alpha; D051745:Protein Kinase C-delta