Int J Biol Sci 2022; 18(8):3358-3373. doi:10.7150/ijbs.68221 This issue Cite
Review
1. Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, Qingdao, 266021, China.
2. Department of Vascular Surgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
3. Department of Radiation Oncology, Sun Yat - Sen University Cancer Center, State Key Laboratory of Oncology in Southern China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.
Piwi-interacting RNAs (piRNAs) are a class of short chain noncoding RNAs that are constituted by 26-30 nucleotides (nt) and can couple with PIWI protein family. piRNAs were initially described in germline cells and are believed to be critical regulators of the maintenance of reproductive line. Increasing evidence has extended our perspectives on the biological significance of piRNAs and indicated that they could still affect somatic gene expression through DNA methylation, chromatin modification and transposon silencing, etc. Many studies have revealed that the dysregulation of piRNAs might contribute to diverse diseases through epigenetic changes represented by DNA methylation and chromatin modification. In this review, we summarized piRNA/PIWI protein-mediated DNA methylation regulation mechanisms and methylation changes caused by piRNA/PIWI proteins in different diseases, especially cancers. Since DNA methylation and inhibitory chromatin marks represented by histone H3 lysine 9 (H3K9) methylation frequently cooperate to silence genomic regions, we also included methylation in chromatin modification within this discussion. Furthermore, we discussed the potential clinical applications of piRNAs as a new type promising biomarkers for cancer diagnosis, as well as the significance of piRNA/PIWI protein-associated methylation changes in treatment, providing disparate insights into the potential applications of them.
Keywords: piRNA, PIWI, DNA methylation, cancer, disease, diagnosis, therapy