HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Tili, E. Articles by Croce, C. M. Search for Related Content PubMed PubMed Citation Articles by Tili, E. Articles by Croce, C. M.

Modulation of miR-155 and miR-125b Levels following Lipopolysaccharide/TNF- Stimulation and Their Possible Roles in Regulating the Response to Endotoxin Shock¹

Esmerina Tili^2,*, Jean-Jacques Michaille^2,*,, Amelia Cimino^*, Stefan Costinean^*, Calin Dan Dumitru^3,, Brett Adair^*, Muller Fabbri^*, Hannes Alder^*, Chang Gong Liu^*, George Adrian Calin^4,* and Carlo Maria Croce^5,*

^* Ohio State University, Department of Molecular Virology, Immunology and Medical Genetics and Comprehensive Cancer Center, Columbus, OH 43210; Institut National de la Santé et de la Recherche Médicale Unité 866,Université de Bourgogne, Dijon, France; and Thomas Jefferson University, Kimmel Cancer Center, Philadelphia, PA 19107

We report here that miR-155 and miR-125b play a role in innate immune response. LPS stimulation of mouse Raw 264.7 macrophages resulted in the up-regulation of miR-155 and down-regulation of miR-125b levels. The same changes also occurred when C57BL/6 mice were i.p. injected with LPS. Furthermore, the levels of miR-155 and miR-125b in Raw 264.7 cells displayed oscillatory changes in response to TNF-. These changes were impaired by pretreating the cells with the proteasome inhibitor MG-132, suggesting that these two microRNAs (miRNAs) may be at least transiently under the direct control of NF-B transcriptional activity. We show that miR-155 most probably directly targets transcript coding for several proteins involved in LPS signaling such as the Fas-associated death domain protein (FADD), IB kinase (IKK), and the receptor (TNFR superfamily)-interacting serine-threonine kinase 1 (Ripk1) while enhancing TNF- translation. In contrast, miR-125b targets the 3'-untranslated region of TNF- transcripts; therefore, its down-regulation in response to LPS may be required for proper TNF- production. Finally, Eµ-miR-155 transgenic mice produced higher levels of TNF- when exposed to LPS and were hypersensitive to LPS/D-galactosamine-induced septic shock. Altogether, our data suggest that the LPS/TNF--dependent regulation of miR-155 and miR-125b may be implicated in the response to endotoxin shock, thus offering new targets for drug design.

The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

¹ This work was supported by Program Project Grants P01CA76259 and P01CA81534 from the National Cancer Institute (to C.M.C.), a Kimmel Scholar award, and a Chronic Lymphocytic Leukemia Research Foundation Grant (to G.A.C.).

² E.T. and J.-J.M. contributed equally to this work.

³ Current address: 3M Center, Saint Paul, MN 55144.

⁴ Current address: Department of Experimental Therapeutics and Department of Cancer Genetics, University of Texas, Monroe Dunaway Anderson Cancer Center, Houston, TX 77030.

⁵ Address correspondence and reprint requests to Dr. Carlo Maria Croce, Comprehensive Cancer Center, Ohio State University, Wiseman Hall, 400 West 12th Avenue, Columbus, OH 43210. E-mail address: Carlo.Croce{at}osumc.edu

⁶ Abbreviations used in this paper: UTR, untranslated region; FADD, Fas-associated death domain protein; IKK, IB kinase ; miRNA, microRNA; Ripk1, receptor (TNFR superfamily)-interacting serine-threonine kinase 1; snRNA, small nuclear RNA.