FOXO1 and precursor B-cell acute lymphoblastic leukemia: In addition, BACH2 had been reported to function as a TSG in B-ALL [40] but showed no activity in 697 cells, so we tracked levels of SIN-SIEW, FOXO3, FOXO1, PRDM1 or BACH2 as single expression constructs in 697 and the ETV6::RUNX1-ALL line, REH, by flow cytometry.