Metabolic rewiring, a cancer hallmark, is one of the key mechanisms that underlie tumorigenesis, tumor progression, and chemoresistance.11 Although hematological malignancies mainly use aerobic glycolysis, some favor OXPHOS to satisfy their energy demands.2,12 Here, we show that lymphoid cells transformed by NPAT-JAK2, a novel fusion, which we found in BCR-ABL1-like ALL, increase both their glycolytic activity and mitochondrial respiration. This evidence concerns the gene JAK2 and cancer.