microRNA-143 downregulates Hexokinase 2 in colon cancer cells

MicroRNAs (miRNAs) have emerged as important gene regulators and are recognized as key players in tumorigenesis. miR-143 is reported to be down-regulated in several cancers, but knowledge of its targets in colon cancer remains limited. To investigate the role of miR-143 in colon cancer, we have employed a microarray based approach to identify miR-143 targets. Based on seed site enrichment analyses and unbiased word analyses, we found a significant enrichment of miRNA binding sites in the 3’-untranslated regions (UTRs) of transcripts down-regulated upon miRNA overexpression. Here we identify Hexokinase 2 (HK2) as a direct target of miR-143 and show that re-introduction of miR-143 in the colon cancer cell line DLD-1 results in a decreased lactate secretion, indicating that miR-143 down-regulation of HK2 affects glucose metabolism in colon cancer cells. DLD-1 cells were transfected with 50 nM miR-143 duplex or mock transfected. Total RNA was harvested 24 hours post-transfection and analyzed on Affymetrix HG-U133 Plus 2.0 human arrays.