MicroRNA-22 and microRNA-140 suppress NF-κB activity by regulating the expression of NF-κB coactivators.

Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Japan.
Biochemical and Biophysical Research Communications (Impact Factor: 2.41). 08/2011; 411(4):826-31. DOI: 10.1016/j.bbrc.2011.07.048
Source: PubMed

ABSTRACT Nuclear factor κB (NF-κB) is a transcription factor that regulates a set of genes that are critical to many biological phenomena, including liver tumorigenesis. To identify microRNAs (miRNAs) that regulate NF-κB activity in the liver, we screened 60 miRNAs expressed in hepatocytes for their ability to modulate NF-κB activity. We found that miRNA-22 and miRNA-140-3p significantly suppressed NF-κB activity by regulating the expression of nuclear receptor coactivator 1 (NCOA1) and nuclear receptor-interacting protein 1 (NRIP1), both of which are NF-κB coactivators. Our results provide new information about the roles of miRNAs in the regulation of NF-κB activity.

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