DNA Damage and Repair of Head and Neck Cancer Cells after Radio- and Chemotherapy

Abstract

DNA repair is critical for successful chemo- and radiotherapy of human tumours, because their genotoxic sensitivity may vary in different types of cancer cells. In this study we have compared DNA damage and the efficiency of its repair after genotoxic treatment with hydrogen peroxide, cisplatin and γ-radiation of head and neck squamous cell carcinoma (HNSCC). Lymphocytes and tissue cells from biopsies of 37 cancer patients and 35 healthy donors as well as the HTB-43 larynx cancer cell line were employed. The cell sensitivity to genotoxic treatment was estimated by the MTT survival assay. The extent of DNA damage and efficiency of its repair was examined by the alkaline comet assay. Among the examined treatments, we found that HNSCC cells were the most sensitive to γ-radiation and displayed impaired DNA repair. In particular, DNA damage was repaired less effectively in cells from HNSCC metastasis than healthy controls. In conclusion, our results suggest that the different genotoxic sensitivity of HNSCC cells may depend on their DNA repair capacity what in turn may be connected with the effectiveness of head and neck cancer therapy.

Risk of second primary cancer after treatment for esophageal cancer: a pooled analysis of nine cancer registries

“…The study has found that radiotherapy for primary cancers was associated with an increased risk of developing second cancer in nearby organs. The development of second primary cancers in the irradiated head and neck area is biologically plausible with potential mechanisms such as DNA damage caused by radiotherapy 29 . An excess incidence of lung cancer was observed at 10 years after radiotherapy.…”

Association of the Arg194Trp and the Arg399Gln Polymorphisms of the XRCC1 Gene With Risk Occurrence and the Response to Adjuvant Therapy Among Polish Women With Breast Cancer

“…6,7 Conversely, it is reported in many studies that the response to anticancer therapy using DNA-reactive drugs may depend on DNA repair efficiency. [8][9][10][11][12][13][14][15][16][17][18][19][20] Therefore DNA repair efficiency may modulate the response of patients with breast cancer to adjuvant therapy. Adjuvant treatment for patients with breast cancer involves radiation therapy and a variety of chemotherapeutic agents, most frequently combinations of cyclophosphamide and anthracyclines.…”

Curcumin Enhances Radiosensitization of Nasopharyngeal Carcinoma via Mediating Regulation of Tumor Stem-like Cells by a CircRNA Network

“…DNA double chain damage repair is an essential mechanism of resistance of tumor cells to radiotherapy [31]. DNA damage can induce DNA damage response signaling (DDR signaling) in the tumor cells.…”