Phase I and Pharmacologic Study of Olaparib in Combination with High-dose Radiotherapy with and without Concurrent Cisplatin for Non-Small Cell Lung Cancer.

Purpose: To identify an MTD of olaparib, a PARP inhibitor, in combination with loco-regional radiotherapy with/without cisplatin for the treatment of non-small cell lung cancer (NSCLC).

Patients And Methods: Olaparib dose was escalated in two groups: radiotherapy (66 Gy/24 fractions in 2.75 Gy/fraction) with and without daily cisplatin (6 mg/m), using time-to-event continual reassessment method with a 1-year dose-limiting toxicity (DLT) period.

Fanconi anemia and homologous recombination gene variants are associated with functional DNA repair defects and poor outcome in patients with advanced head and neck squamous cell carcinoma.

Mutations in Fanconi Anemia or Homologous Recombination (FA/HR) genes can cause DNA repair defects and could therefore impact cancer treatment response and patient outcome. Their functional impact and clinical relevance in head and neck squamous cell carcinoma (HNSCC) is unknown. We therefore questioned whether functional FA/HR defects occurred in HNSCC and whether they are associated with FA/HR variants.

Targeted radiosensitization of cells expressing truncated DNA polymerase {beta}.

Ionizing radiation (IR) is an effective anticancer treatment, although failures still occur. To improve radiotherapy, tumor-targeted strategies are needed to increase radiosensitivity of tumor cells, without influencing normal tissue radiosensitivity. Base excision repair (BER) and single-strand break repair (SSBR) contribute to the determination of sensitivity to IR.

Mechanism of cell killing after ionizing radiation by a dominant negative DNA polymerase beta.

Several types of DNA lesion are induced after ionizing irradiation (IR) of which double strand breaks (DSBs) are expected to be the most lethal, although single strand breaks (SSBs) and DNA base damages are quantitatively in the majority. Proteins of the base excision repair (BER) pathway repair these numerous lesions. DNA polymerase beta has been identified as a crucial enzyme in BER and SSB repair (SSBR).

Cell cycle phase dependent role of DNA polymerase beta in DNA repair and survival after ionizing radiation.

Purpose: The purpose of the present study was to determine the role of DNA polymerase beta in repair and response after ionizing radiation in different phases of the cell cycle.

Methods And Materials: Synchronized cells deficient and proficient in DNA polymerase beta were irradiated in different phases of the cell cycle as determined by BrdU/flow cytometry. Cell kill and DNA repair were assessed by colony formation and alkaline comet assays, respectively.