However, the contribution of STAT3 to T-ALL leukemogenesis is debatable, because no recurrent STAT3 mutations have been found in patients with T-ALL (19), and it is more associated with mature T cell cancers, such as T cell large granular lymphocytic leukemia or NK cell or NK/T cell leukemia (68, 69). This evidence concerns the gene STAT3 and T-cell leukemia.