Given the well‐established causal relationship between the NUDT15 enzyme activity and metabolism of thiopurine (e.g., 6MP) and the increased antileukemic efficacy of 6MP for NUDT15 deficient leukemia at cell line and mouse levels [24, 26], we hypothesized that somatic deletion of NUDT15 could also sensitize the solid cancer cells to 6MP. This evidence concerns the gene NUDT15 and leukemia.