Association between Human Endogenous Retrovirus and Cancers Using RNA-Seq Data

It is estimated that viral infections contribute to 15-20% of all human cancers. It is interested in addressing whether Human Endogenous Retroviruses (HERVs), which have invaded our genome at least 25 million years ago, play any roles in cancer processing. Not until the rapid development of biotechnologies, such as next generation sequencing, have scientists realized that the once called “junk DNA” has its activity to express RNA. Among these non-coding RNA, HERVs account for 8% of our entire genome. The common structure of retroviral genes consists of gag, pol and env, and which are flanked by regulatory long terminal repeats (LTRs). Previous research on the association between HERVs and cancer is using deducting methods to assay HERVs one by one on the tumor biopsies. Here in this two-year proposal we propose to use RNA-Seq data of tumor samples to screen and map the whole HERVs genome to identify the differentially expressed HERVs, and which are subsequent to experimental validation using tumor biopsies. With complete genome-wide screening of RNA-Seq data and HERVs in genomic scale, it will provide insight into the mysterious roles of HERV in cancers.