Identification and characterization of Dicer1e, a Dicer1 protein variant, in oral cancer cells

Molecular Cancer

Research

Andrew Jakymiw¹  Aaron Blackshaw¹  Lourdes M Andino¹  Christopher C Attaway¹  Betsy Butler¹  Liliana P Cantini¹  Anca Dumitriu² 

[1] Department of Oral Health Sciences and Center for Oral Health Research, Hollings Cancer Center, Medical University of South Carolina, 173 Ashley Avenue, 29425, Charleston, SC, USA;Department of Pediatrics, Division of Hematology/Oncology, Medical University of South Carolina, 135 Rutledge Avenue, 29425, Charleston, SC, USA;

关键词: Dicer1;    Dicer1e;    RNAi;    EMT;    miRNA;    Protein variant;    Oral cancer;   

DOI  :  10.1186/1476-4598-13-190

 received in 2014-02-19, accepted in 2014-08-05,  发布年份 2014

来源: Springer

【 摘 要 】

BackgroundThe human dicer1 gene has been predicted to produce several mRNA variants that encode truncated Dicer1 proteins of varying lengths. One of these Dicer1 variants, Dicer1e, was recently found to be differentially expressed in breast cancer cells. Because the expression and function of the Dicer1e protein variant has not been well characterized and the underlying molecular mechanisms for the development of oral squamous cell carcinomas (OSCCs) are poorly understood, the present study sought to characterize the biological role of Dicer1e and determine its relationship, if any, to OSCC pathogenesis.MethodsWestern blot analyses were used to examine Dicer1e expression levels in a panel of oral cancer cells/tissues and during epithelial-mesenchymal transition (EMT), followed by 5′/3′-RACE analyses to obtain the full-length Dicer1e transcript. Biochemical fractionation and indirect immunofluorescent studies were performed to determine the cellular localization of Dicer1e and the effects of Dicer1e silencing on cancer cell proliferation, clonogenicity, and drug sensitivity were also assessed.ResultsDicer1e protein levels were found to be overexpressed in OSCC cell lines of epithelial phenotype and in OSCC tissues with its levels downregulated during EMT. Moreover, the Dicer1e protein was observed to predominantly localize in the nucleus. 5′/3′-RACE analyses confirmed the presence of the Dicer1e transcript and silencing of Dicer1e impaired both cancer cell proliferation and clonogenicity by inducing either apoptosis and/or G2/M cell cycle arrest. Lastly, Dicer1e knockdown enhanced the chemosensitivity of oral cancer cells to cisplatin.ConclusionThe expression levels of Dicer1e influence the pathogenesis of oral cancer cells and alter their response to chemosensitivity, thus supporting the importance of Dicer1e as a therapeutic target for OSCCs.

【 授权许可】

Unknown   
© Cantini et al.; licensee BioMed Central Ltd. 2014. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.