[Comparison of DNA-dependent protein kinase catalytic subunit expression in two lung adenocarcinoma cell lines with different radiosensitivity].
OBJECTIVE
To investigate DNA-dependent protein kinase catalytic subunit (DNA-PKcs) content and activity in lung adenocarcinoma cell lines and its correlation with radiosensitivity.


METHODS
The content and activity of DNA-PKcs were analyzed in two lung adenocarcinoma cell lines A549 and H1299 by Western blotting and the Signa TECT DNA-PK assay kit. The dose-survival relationship for two cell lines was analyzed using clonogenic formation assay.


RESULTS
A549 was more radiosensitive than H1299. The survival fractions at 2 Gy (SF2) were 0.7412 in A549 cell line and 0.2473 in H1299 cell line. The content of DNA-PKcs was significantly higher in A549 cells than in H1299 cells (t=10.37, P<0.001). The integrated optical densities were 3.29-/+0.44 in A549 cells and 0.50-/+0.17 in H1299 cells. DNA-PKcs activities in A549 and H1299 cells were 8.29-/+1.37 and 2.47-/+1.09, respectively, showing a significant difference between them (t=5.76, P=0.005).


CONCLUSIONS
DNA-PKcs is an important factor to affect the radiosensitivity of lung adenocarcinoma cell lines.
Cen
Wei-Jian
WJ
Department of Radiation Oncology, Guangdong Provincial People's Hospital, Guangzhou 510080, China.
Pan
Yi
Y
Li
Wei-Xiong
WX
Yang
Su-Qing
SQ
D000230:Adenocarcinoma / Q000201:enzymology* / Q000473:pathology; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D006801:Humans; D008175:Lung Neoplasms / Q000201:enzymology* / Q000473:pathology; D011836:Radiation Tolerance
C109198:CIB1 protein, human; D002135:Calcium-Binding Proteins