Enhanced radiosensitivity of head and neck cancer cells to proton therapy via hyperthermia-induced homologous recombination deficiency.

Background And Purpose: Radiotherapy induces tumor cell killing by generating DNA double strand breaks (DSBs). The effectiveness of radiotherapy is significantly influenced by the repair of DSBs, which counteracts this lethal effect. Current investigations are focused on determining whether non-homologous end joining (NHEJ) or homologous recombination is the predominant repair pathway following proton and photon radiation.

Synergistic Roles of Non-Homologous End Joining and Homologous Recombination in Repair of Ionizing Radiation-Induced DNA Double Strand Breaks in Mouse Embryonic Stem Cells.

DNA double strand breaks (DSBs) are critical for the efficacy of radiotherapy as they lead to cell death if not repaired. DSBs caused by ionizing radiation (IR) initiate histone modifications and accumulate DNA repair proteins, including 53BP1, which forms distinct foci at damage sites and serves as a marker for DSBs. DSB repair primarily occurs through Non-Homologous End Joining (NHEJ) and Homologous Recombination (HR).

Enhanced radiation sensitivity, decreased DNA damage repair, and differentiation defects in airway stem cells derived from patients with chronic obstructive pulmonary disease.

Radiation therapy (RT) is a common treatment for lung cancer. Still, it can lead to irreversible loss of pulmonary function and a significant reduction in quality of life for one-third of patients. Preexisting comorbidities, such as chronic obstructive pulmonary disease (COPD), are frequent in patients with lung cancer and further increase the risk of complications.

Multi-scale cellular imaging of DNA double strand break repair.

Live-cell and high-resolution fluorescence microscopy are powerful tools to study the organization and dynamics of DNA double-strand break repair foci and specific repair proteins in single cells. This requires specific induction of DNA double-strand breaks and fluorescent markers to follow the DNA lesions in living cells. In this review, where we focused on mammalian cell studies, we discuss different methods to induce DNA double-strand breaks, how to visualize and quantify repair foci in living cells.

[Diaper dermatitis is not always a harmless condition].

Background: Diaper dermatitis in children is common and usually harmless. Often the cause is irritation, a secondary candida infection or eczema, for which treatment is simple and effective. In this paper we show that a therapy resistant diaper dermatitis can be the diagnostic clue to the rare but important diagnosis Langerhans cell histiocytosis (LCH).