Institute of Oral Biology and Department of Dentistry, School of Dentistry, National Yang-Ming University, Taipei, Taiwan.
Oral Oncol. 2013 Jan;49(1):27-33. doi: 10.1016/j.oraloncology.2012.07.003. Epub 2012 Jul 31.
MicroRNAs (miRNAs) are endogenous small non-coding RNAs that negatively regular target gene expression by RNA interference. The processing of the pre-miRNA hairpin generates a miRNA duplex, which consists of a miRNA (guide strand) and a miRNA() (passenger strand). miR-31 is an oncogenic miRNA and is up-regulated in oral squamous cell carcinoma (OSCC). miR-31() shows a high level of conservation across species and, based on this, this study hypothesized that miR-31(*) is a functional miRNA.
The expression of miR-31 and miR-31* in OSCC tissues and oral cells were analyzed. Functional studies were performed on OSCC cells.
miR-31() is up-regulated in OSCC tissues, but its expression is less abundant than miR-31. miR-31() decreases the proliferation and migration of both SAS and Fadu cells. Furthermore, miR-31() targets the 3'UTR of RhoA and is able to down-regulate RhoA expression. Knockdown of RhoA expression is known to decrease the proliferation and migration of OSCC cells. However, up-regulation of both miR-31 and miR-31() by delivery of pre-mir-31 does still enhance OSCC oncogenicity.
miR-31() is a functional miRNA involving in regulating RhoA, and the activity of miR-31()'s activity seems to counteract the functions of miR-31 during OSCC tumorigenesis.
微小 RNA（miRNA）是内源性的小非编码 RNA，通过 RNA 干扰负调控靶基因表达。前 miRNA 发夹的加工产生 miRNA 双链体，其由 miRNA（引导链）和 miRNA()（过客链）组成。miR-31 是一种致癌 miRNA，在口腔鳞状细胞癌（OSCC）中上调。miR-31()在物种间具有高度保守性，基于此，本研究假设 miR-31(*)是一种功能性 miRNA。
分析 OSCC 组织和口腔细胞中 miR-31 和 miR-31*的表达。在 OSCC 细胞上进行功能研究。
miR-31()在 OSCC 组织中上调，但表达量低于 miR-31。miR-31()降低 SAS 和 Fadu 细胞的增殖和迁移。此外，miR-31()靶向 RhoA 的 3'UTR 并能够下调 RhoA 表达。已知 RhoA 表达的敲低会降低 OSCC 细胞的增殖和迁移。然而，通过递送前 miR-31 上调 miR-31 和 miR-31()仍增强 OSCC 的致癌性。
miR-31()是一种功能性 miRNA，涉及调节 RhoA，miR-31()的活性似乎在 OSCC 肿瘤发生过程中抵消了 miR-31 的功能。
