[X-ray irradiation enhances tumor necrosis factor receptor p55 expression in human colorectal cancer cells and inhibits the release of its soluble form in vitro].
OBJECTIVE
To investigate the effects of X ray on human colorectal cancer cells for their tumor necrosis factor receptor-p55 (TNFR-p55) expression and release of soluble soluble TNFR-p55 (sTNFR-p55) in vitro.


METHODS
The protein expression of TNFR-p55 in Lovo cells exposed to X-ray was detected using immunohistochemistry, and enzyme-linked immunosorbent assay was used to examine the levels of sTNFR-p55 in the supernatants of the cell culture. The cell apoptosis of the exposed cells was analyzed with flow cytometry, and the changes in cell morphology were observed microscopically.


RESULTS
X-ray exposure of cells resulted in a strong increase in TNFR-p55 expression of (P<0.01) and LoVo cell apoptosis (P<0.05). The levels of sTNFR-p55 in the supernatant of cells with X-ray exposure was significantly lowered in comparison with the levels before exposure (P<0.01). Optical microscopy showed that the exposed LoVo cells shrank and became spherical with cytoplasmic condensation and nuclear pyknosis.


CONCLUSIONS
X-ray exposure can induce LoVo cell apoptosis by increasing TNFR-p55 expression on the cell membrane and inhibiting the release of sTNFR-p55 in the supernatants.
Gao
Lei
L
Department of Imaging, Second Affiliated Hospital, Guangzhou University of Traditional Chinese Medicine, Guangzhou 510120, China. gzgaolei@126.com
Bai
Lan
L
Shi
Wei-min
WM
Nan
Qing-zhen
QZ
Mao
Zhan-bin
ZB
D017209:Apoptosis; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D047888:Receptors, Tumor Necrosis Factor, Type I / Q000235:genetics / Q000378:metabolism*; D053319:Tumor Necrosis Factor Decoy Receptors / Q000235:genetics / Q000378:metabolism*; D014965:X-Rays
D047888:Receptors, Tumor Necrosis Factor, Type I; D053319:Tumor Necrosis Factor Decoy Receptors; C069521:recombinant human tumor necrosis factor-binding protein-1