MicroRNA expression in 6 human leukemia cell lines. (A-F) Proportion (in percent) of the most abundantly expressed miRNAs in 6 human leukemia cell lines: (A) THP-1, (B) UT-7, (C) KG-1, (D) HL-60, (E) MDSL, and (F) KG-1a. White portion of the pie chart represents miRNAs reads that are expressed below background.