OLFM4 and chronic myelogenous leukemia, BCR-ABL1 positive: To evaluate the potential role of OLFM4 in survival of CML iCD34+ cells, we tested the effect of OLFM4 knocking-down on iCD34+ cell apoptosis using OLFM4-targeted small interference RNA (siOLFM4) composed of four OLFM4-specific siRNAs.