Enhancers of Polycomb 1 & 2 in normal and leukaemic haematopoiesis

A knockdown screen of chromatin regulatory genes in human THP1 MLL-AF9 AML cells identified EPC1 and EPC2 as required for cell survival. Normal myeloid progenitor cells did not require EPC1 or EPC2 for their function. To determine the transcriptional consequences of EPC knockdown, normal murine granulocyte-macrophage progenitor (GMP) cells, or murine MLL-AF9 AML GMP-like cells, were FACS purified from mice and infected with lentiviral vectors targeting EPC1 or EPC2 for knockdown, or a non-tageting control. 42 hours later knockdown or control cells were FACS purified and exon array analysis was performed on the sorted populations. For normal GMP cells, three biological replicates (three separate animals) each of control cells, EPC1 knockdown cells and EPC2 knockdown cells; for MLL-AF9 AML GMP-like cells cells, three biological replicates (three separate leukaemias) each of control cells, EPC1 knockdown cells and EPC2 knockdown cells.