Microrna-146a and Microrna-146b Regulate Human Dendritic Cell Apoptosis and Cytokine Production by Targeting TRAF6 and IRAK1 Proteins

Authors

Haein Park, From the Department of Pediatrics, Division of Hematology, Oncology, and Stem Cell Transplantation, and.
Xin Huang, From the Department of Pediatrics, Division of Hematology, Oncology, and Stem Cell Transplantation, and.
Changming Lu, the Institute of Oral Health, School of Dentistry, University of Alabama at Birmingham, Birmingham, Alabama 35233.
Mitchell S. Cairo, From the Department of Pediatrics, Division of Hematology, Oncology, and Stem Cell Transplantation, and the Departments of Microbiology and Immunology, Cell Biology and Anatomy, Pathology, and Medicine, New York Medical College, Valhalla, New York 10595 and.
Xianzheng Zhou, From the Department of Pediatrics, Division of Hematology, Oncology, and Stem Cell Transplantation, and the Departments of Microbiology and Immunology, Cell Biology and Anatomy, xianzheng_zhou@nymc.edu.

Author Type(s)

Faculty

DOI

10.1074/jbc.M114.591420

Journal Title

The Journal of Biological Chemistry

First Page

2831

Last Page

41

Document Type

Article

Publication Date

1-30-2015

Abstract

We have previously reported 27 differentially expressed microRNAs (miRNAs) during human monocyte differentiation into immature dendritic cells (imDCs) and mature DCs (mDCs). However, their roles in DC differentiation and function remain largely elusive. Here, we report that microRNA (miR)-146a and miR-146b modulate DC apoptosis and cytokine production. Expression of miR-146a and miR-146b was significantly increased upon monocyte differentiation into imDCs and mDCs. Silencing of miR-146a and/or miR-146b in imDCs and mDCs significantly prevented DC apoptosis, whereas overexpressing miR-146a and/or miR-146b increased DC apoptosis. miR-146a and miR-146b expression in imDCs and mDCs was inversely correlated with TRAF6 and IRAK1 expression. Furthermore, siRNA silencing of TRAF6 and/or IRAK1 in imDCs and mDCs enhanced DC apoptosis. By contrast, lentivirus overexpression of TRAF6 and/or IRAK1 promoted DC survival. Moreover, silencing of miR-146a and miR-146b expression had little effect on DC maturation but enhanced IL-12p70, IL-6, and TNF-α production as well as IFN-γ production by IL-12p70-mediated activation of natural killer cells, whereas miR-146a and miR-146b overexpression in mDCs reduced cytokine production. Silencing of miR-146a and miR-146b in DCs also down-regulated NF-κB inhibitor IκBα and increased Bcl-2 expression. Our results identify a new negative feedback mechanism involving the miR-146a/b-TRAF6/IRAK1-NF-κB axis in promoting DC apoptosis.

Recommended Citation

Park, H., Huang, X., Lu, C., Cairo, M. S., & Zhou, X. (2015). Microrna-146a and Microrna-146b Regulate Human Dendritic Cell Apoptosis and Cytokine Production by Targeting TRAF6 and IRAK1 Proteins. The Journal of Biological Chemistry, 290 (5), 2831-41. https://doi.org/10.1074/jbc.M114.591420