Anti-apoptotic role of S100A8 in X-ray irradiated keratinocytes.
BACKGROUND
Ionizing radiation is used to treat a lot of cancers, however, it also produced unwanted side effect on normal tissues, such as radiodermatitis. We previously established an animal model for radiodermatitis, and identified many of radiation-induced genes by cDNA microarray. Of the candidates, we chose S100A8 gene for a further study.


OBJECTIVE
The aim of this study is to investigate the functional role of S100A8 in X-ray irradiated keratinocytes.


METHODS
RT-PCR and immunohistochemistry were performed to demonstrate the S100A8 induction by X-ray irradiation. HaCaT keratinocytes were transduced with the recombinant adenovirus expressing GFP-S100A8, and then effects on cell cycle and apoptosis were analyzed using flow cytometry and Western blot.


RESULTS
X-ray irradiation markedly induced S100A8 expression in the hyperplastic epidermis of mouse. Overexpression of S100A8 by adenoviral transduction led to the enhancement of cell proliferation in the absence and/or presence of X-ray irradiation, as compared with Ad/GFP control group. Furthermore, overexpression of S100A8 significantly protected the X-ray-induced apoptosis.


CONCLUSIONS
These results suggest that S100A8 have an anti-apoptotic role in X-ray irradiated keratinocytes.
Lee
Young-Sook
YS
Department of Dermatology and Research Institute of Medical Sciences, School of Medicine, Chungnam National University, 640 Daesa-dong, Daejeon, Republic of Korea.
Sohn
Kyung-Cheol
KC
Jang
Sunhyae
S
Lee
Young
Y
Hwang
Chul
C
Kim
Ki-Hwan
KH
Cho
Moon-June
MJ
Kim
Chang Deok
CD
Lee
Jeung-Hoon
JH
D000256:Adenoviridae; D000818:Animals; D040501:Calgranulin A / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D049109:Cell Proliferation; D018014:Gene Transfer Techniques; D006801:Humans; D015603:Keratinocytes / Q000528:radiation effects*; D008297:Male; D051379:Mice; D008812:Mice, Hairless; D014965:X-Rays
D040501:Calgranulin A