ATM mutation and radiosensitivity: An opportunity in the therapy of mantle cell lymphoma.

ATM (ataxia telangiectasia mutated) is a DNA damage signaling-initiation kinase which has diverse function in responding to genotoxic stress to maintain its genomic integrity. Cells harboring loss-of-function ATM deficiencies demonstrate extreme radiosensitivity. The scope of radiotherapy has been considered very limited among patients with biallelic mutations or deletions of ATM due to its toxic effect on normal tissue. Mantle cell lymphoma (MCL) is a highly chemo-refractory tumor with generally poor outcome, especially if the patients develop resistance to frontline drugs. ATM is the most frequently mutated gene in MCL and recent experimental evidence demonstrated that this mutational status can be taken advantage of using radiotherapy. Radiotherapy should be considered in the treatment of mantle cell lymphoma with a curative intent.