DNA-dependent protein kinase content and activity in lung carcinoma cell lines: correlation with intrinsic radiosensitivity

Eur J Cancer. 1999 Jan;35(1):111-6. doi: 10.1016/s0959-8049(98)00289-5.


Intrinsic radiosensitivity and rejoining of radiation-induced DNA double-strand breaks (DNA-dsb) were analysed in five lung carcinoma cell lines: U-1285, U-1906, H-69, H-82 and U-1810. RS correlated with both the initial phase of DNA-dsb rejoining, at 15 min (r2 = 0.818) and the late phase, at 120 min postirradiation (r2 = 0.774), the most sensitive cell line (U-1285) showing least dsb rejoining and the most resistant (U-1810) showing most dsb rejoining of all five cell lines studied. As DNA-PK has been recognised as an important molecular component involved in DNA-dsb repair, we analysed content and activity of this kinase. We found that DNA-PK content and activity correlated with RS (r2 = 0.941 and r2 = 0.944, respectively). The lowest DNA-dependent content/activity was found in the most radiosensitive cells, U-1285 and H-69, whilst the highest content/activity was found in the most radioresistant cells U-1810. These results suggest a correlation between RS and DNA-PK content/activity in lung carcinoma cell lines.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blotting, Western
  • Carcinoma, Small Cell / enzymology*
  • Carcinoma, Small Cell / genetics
  • DNA Repair*
  • DNA, Neoplasm / metabolism
  • DNA, Neoplasm / radiation effects*
  • DNA-Activated Protein Kinase
  • DNA-Binding Proteins*
  • Humans
  • Lung Neoplasms / enzymology*
  • Lung Neoplasms / genetics
  • Nuclear Proteins
  • Protein-Serine-Threonine Kinases / metabolism*
  • Radiation Tolerance
  • Tumor Cells, Cultured / radiation effects


  • DNA, Neoplasm
  • DNA-Binding Proteins
  • Nuclear Proteins
  • DNA-Activated Protein Kinase
  • PRKDC protein, human
  • Protein-Serine-Threonine Kinases