Molecular background and therapeutic perspectives of acute lymphoblastic leukemia BCR-ABL1-like

Abstract

BCR-ABL1-like acute lymphoblastic leukemia (ALL) is newly identified subtype of high-risk B-cell progenitor acute lymphoblastic leukemia (BCP-ALL), which exhibit gene expression signature similar to that of BCR-ABL1–positive leukemia, but without characteristic BCR-ABL1 gene fusion. Since the frequency of the BCR-ABL1-like ALL is relatively high (15%) and the risk of relapse issignificantly increased, molecular pathogenesis of this subtype is widely explored. Approximately 80% of genetic lesions in the BCR-ABL1-like ALL refer to genes involved in B-cell differentiation and maturation (IKZF1, PAX5, E2A, EBF1 and VPREB1) as well as to genes that regulateB-lymphocyte proliferation (CRLF2, CDKN2A/2B). Moreover, BCR-ABL1-like ALL is also characterized by gene fusions involving PDGFRB, ABL1, JAK genes which activate kinases of specific,metabolic pathways responsible for cancer development. Many of identified up-regulated signaling pathways can be inhibited by currently clinically available molecular targeted drugs.