BCR and acute leukemia: Therapeutic interventions aiding to reduce intracellular spermidine availability may prevent eIF5A from exerting its pro-tumorigenic function in acute leukemias, mainly in Ph+ ALL cases, with a potential relevance also in the 0.3% of AML cases carrying the BCR activator of RhoGEF and GTPase::ABL proto-oncogene 1 (BCR::ABL1) fusion gene [78].