The immunohistochemical expression of DNA-PKCS and Ku (p70/p80) in head and neck cancers: relationships with radiosensitivity
| Autor: | Bengt Magnusson, Nicholas J Slevin, Ewa Karlsson, Rolf Lewensohn, Catharine M L West, Anders Nilsson, Marie Svensson, Claes Mercke, Thomas Björk-Eriksson |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
Male
Cancer Research Pathology medicine.medical_specialty Cell Radiation Tolerance Gene expression Biopsy medicine Humans Radiology Nuclear Medicine and imaging Radiosensitivity Clonogenic assay Ku Autoantigen DNA-PKcs Radiation medicine.diagnostic_test business.industry Head and neck cancer Calcium-Binding Proteins DNA Helicases Nuclear Proteins Antigens Nuclear DNA Neoplasm medicine.disease Immunohistochemistry Neoplasm Proteins DNA-Binding Proteins medicine.anatomical_structure Oncology Head and Neck Neoplasms Cancer research Female business |
| Zdroj: | International journal of radiation oncology, biology, physics. 45(4) |
| ISSN: | 0360-3016 |
| Popis: | The DNA-PK complex is one of the major pathways by which mammalian cells respond to DNA double-strand breaks induced by ionizing radiation. This study evaluated the relationship between the immunohistochemical expression of the individual components of DNA-PK and cellular radiosensitivity in head and neck cancers.Biopsies from patients with previously untreated squamous cell carcinomas of the head and neck were assessed for inherent tumor radiosensitivity measured as the surviving fraction at 2 Gy (SF2) using a soft agar clonogenic assay. Paraffin-embedded tumor material from 64 successfully grown specimens was immunohistochemically stained for expression of DNA-PKcs and Ku (p70/p80). The same tumor material was previously analyzed for the immunohistochemical expression of p53.A significant correlation was found between the degree of expression of DNA-PKcs and Ku (p70/p80) (r = 0.55, p0.001). There were no overall significant differences in the levels of expression of DNA-PKcs and Ku (p70/p80) in tumors from patients of either sex, different sites, histologies, and stages. No relationship was found between SF2 and the expression of either DNA-PKcs (r = 0.22, p = 0.081) or Ku (p70/p80) (r = 0.064, p = 0.62). Comparison with previous immunohistochemical characterization showed no significant correlations between the expression levels of p53 and either DNA-PKcs (r = 0.093, p = 0.46) or Ku (p70/p80) (r = -0.17, p = 0.17).This study suggests that determining the immunohistochemical expression of DNA-PK in head and neck cancers from multiple sites does not have a role as a predictive assay of tumor in vitro radiosensitivity. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|