[Enhancement of radio sensitivity in nasopharyngeal cancer cells by the own regulation of VEGF expression after adenovirus-E1A gene therapy].
OBJECTIVE
To determine the effect of Ad-E1A gene therapy on the radiosensitivity of nasopharyngeal carcinoma cell by downregulating the expression of VEGF in vitro.


METHODS
The human nasopharyngeal carcinoma CNE-2Z cell lines were investigated. The recombinant adenovirus vector containing E1A gene was used for this study. After CNE-2Z cells was treated with PBS, Ad-beta-gal and Ad-E1A for 48 h, the three groups were irradiated in different doses at 0, 2.4, 6, 8 and 10 Gy, the cytotoxicity was determined by MTT assay and cell cycle was analysis by flow cytometry. The VEGF expression were evaluated by RT-PCR assay and immunocytochemical analysis.


RESULTS
Significant cell deaths by IR were observed in a dose dependent manner in the three group CNE-2Z cells. After transduction of the E1A gene into CNE-2Z cells, the sensitivity of these cells to radiation was enhanced than the PBS treated group and Ad-beta-gal treated group. Cell growth inhibition in Ad-E1A group by IR was strongly enhanced than Ad-beta-gal treated group and PBS treated group. RT-PCR assay and immunocytochemical analysis showed VEGF expression was downregulated in Ad-E1A treated group.


CONCLUSIONS
E1A gene therapy can effectively enhance the nasopharyngeal carcinoma cell sensitivity to the radiotherapy by down-regulating VEGF expression. These findings may pave the way for efficient radiation-gene therapy to NPC in future.
Zhou
Rongrong
R
Department of Oncology, Xiangya Hospital, Central South University, Changsha, 410008, China. rrzhou99@yahoo.com
Xiao
Zhiqiang
Z
Liao
Yuping
Y
Xiao
Huaping
H
D000256:Adenoviridae / Q000235:genetics; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D015316:Genetic Therapy; D005822:Genetic Vectors; D006801:Humans; D009303:Nasopharyngeal Neoplasms / Q000235:genetics / Q000378:metabolism / Q000532:radiotherapy*; D011836:Radiation Tolerance; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*
C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A