ABSTRACT
Mixed phenotype acute leukemia (MPAL) is a rare subtype of acute leukemia characterized by leukemic blasts presenting myeloid and lymphoid markers. Here we report data from integrated genomic analysis on 31 MPAL samples and compare molecular profiling with that from acute myeloid leukemia (AML), B cell acute lymphoblastic leukemia (B-ALL), and T cell acute lymphoblastic leukemia (T-ALL). Consistent with the mixed immunophenotype, both AML-type and ALL-type mutations are detected in MPAL. Myeloid-B and myeloid-T MPAL show distinct mutation and methylation signatures that are associated with differences in lineage-commitment gene expressions. Genome-wide methylation comparison among MPAL, AML, B-ALL, and T-ALL sub-classifies MPAL into AML-type and ALL-type MPAL, which is associated with better clinical response when lineage-matched therapy is given. These results elucidate the genetic and epigenetic heterogeneity of MPAL and its genetic distinction from AML, B-ALL, and T-ALL and further provide proof of concept for a molecularly guided precision therapy approach in MPAL.
Subject(s)
DNA Methylation , Gene Expression Regulation, Leukemic , Genomics/methods , Leukemia, Biphenotypic, Acute/genetics , Mutation , Adult , Diagnosis, Differential , Female , Humans , Leukemia, Biphenotypic, Acute/diagnosis , Leukemia, Biphenotypic, Acute/therapy , Leukemia, Myeloid, Acute/diagnosis , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/therapy , Male , Middle Aged , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/genetics , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/therapy , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/genetics , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/therapy , Survival AnalysisABSTRACT
Rx is a paired-like homeobox gene that is required for vertebrate eye formation. Mice lacking Rx function do not develop eyes or the posterior pituitary. To determine whether Rx is required cell autonomously in these tissues, we generated embryonic chimeras consisting of wild type and Rx-/- cells. We found that in the eye, Rx-deficient cells cannot participate in the formation of the neuroretina, retina pigment epithelium and the distal part of the optic stalk. In addition, in the ventral forebrain, Rx function is required cell autonomously for the formation of the posterior pituitary. Interestingly, Rx-/- and wild type cells segregate before the morphogenesis of these two tissues begins. Our observations suggest that Rx function is not only required for the morphogenesis of the retina and posterior pituitary, but also prior to morphogenesis, for the sorting out of cells to form distinct fields of retinal/pituitary cells.
