The prognostically important 1;19 chromosomal translocation can alter the E2A gene on chromosome 19p13 in childhood B-cell precursor acute lymphoblastic leukemia (ALL), leading to formation of a fusion gene (E2A-PBX1) that encodes a hybrid transcription factor with oncogenic potential.
To determine whether methylation differences between mostly fatal TCF3-HLF and curable TCF3-PBX1 pediatric acute lymphoblastic leukemia subtypes can be associated with differential gene expression and remission.
Folylpolyglutamate synthetase (FPGS) activity was higher in B vs T lineage ALL (p<0.005), MTX influx and FPGS activity were higher in hyperdiploid vs non-hyperdiploid ALL (p<0.03), MTX influx and FPGS activity were lower in the t(12;21) (ETV6-RUNX1) subtype (p<0.05), and the ratio of FPGS to γ-glutamyl hydrolase (GGH) activity was lower in the t(1;19) (TCF3-PBX1) subtype (p<0.03) than other genetic subtypes.
We aimed to assess TCF3 rearrangement in newly diagnosed pediatric ALL patients in relation to clinical and laboratory parameters, CNS relapse, and clinical outcome.
The <i>ERG</i> risk genotype was underrepresented in ALL with the <i>ETV6-RUNX1</i> fusion (<i>P</i> < .0005) but enriched in the <i>TCF3-PBX1</i> subtype (<i>P</i> < .05).
Drug response profiling of matched patient-derived xenografts revealed a distinct profile for TCF3-HLF ALL with resistance to conventional chemotherapeutics but sensitivity to glucocorticoids, anthracyclines and agents in clinical development.
The t(1;19)(q23;p13), which results in a fusion of TCF3 (previously E2A) at 19p13 with PBX1 at 1q23, is one of the most common translocations in acute lymphoblastic leukemia (ALL).
Drug response profiling of matched patient-derived xenografts revealed a distinct profile for TCF3-HLF ALL with resistance to conventional chemotherapeutics but sensitivity to glucocorticoids, anthracyclines and agents in clinical development.