Combined exposure to X-irradiation followed by N-ethyl-N-nitrosourea treatment alters the frequency and spectrum of Ikaros point mutations in murine T-cell lymphoma

► Ionizing radiation above a threshold dose synergistically induced ENU lymphomagenesis. ► Ionizing radiation below the threshold antagonized ENU lymphomagenesis. ► The synergy resulted in an increased frequency of point mutation of Ikaros. ► The type of mutations induced by combined treatment was ENU-specific.