MicroRNAs(miRNAs) constitute a family of small non-coding RNA molecules 22-25 nucleotides in length.miRNAs control the expression of target genes at the post-transcriptional level by inhibiting translation or by degrading target mRNA through binding to complementary sequences in the 3'-untranslated regions.Recent studies have demonstrated that miRNAs are intimately involved in processes leading to nasopharyngeal carcinoma,such as the Epstein-Barr virus-encoded latent membrane protein 1 activated signal transduction pathways,gene-regulatory networks,mitosis,tumor angiogenesis,invasion and migration.Exploring the relationship between miRNAs and the development of nasopharyngeal carcinoma,will further the understanding of this cancer and provide new avenues for diagnosis and treatment.
ZHAO LuQing1,2,3,CHEN Xue1,2,3 & CAO Ya1,2,3 1 Key Laboratory of Carcinogenesis and Invasion,Ministry of Education,Changsha 410078,China
In the cell nucleus,DNA is wound around histone proteins,which are then packed together to form chromatin.Histones can be chemically tagged by methyl and acetyl groups.Polycomb group (PcG) proteins attach methyl groups to genes,which block their activity.This is similar to the attachment of methyl groups to gene promoters by DNA methyltransferases (DNMTs).This action is directly linked with tumor initiation and metastasis via the promotion of anti-senescence and anti-apoptosis pathways,and by facilitating epithelial mesenchymal transition (EMT).Cell fate transcriptional factors (CFTFs) and long non-coding RNAs (long ncRNAs) recruit PcG proteins to the promoters of tumor suppressor genes,resulting in epigenetic gene silencing by influencing chromatin structure and DNA accessibility.Thus,PcG proteins are potential diagnostic markers and targets for new chemoprevention and therapeutic strategies.
XIAO LanBo 1,2,3,TAO YongGuang 1,2,3,LI LiLi 1,2,3,4 & CAO Ya 1,2,31 Key Laboratory of Carcinogenesis of Ministry of Health,Xiangya School of Medicine,Central South University,Changsha 410078,China
