Using bioinformatics and epidemiologic approaches, Zhifu Sun, M.D., studies disease development mechanisms, early diagnosis and prognosis biomarkers, and new targets for personalized medicine. Dr. Sun works on both cancer and noncancer diseases, including lung cancer, GI cancers, and autoimmune disorders such as Crohn's disease, primary biliary cholangitis and primary sclerosing cholangitis.
- Lung cancer etiology, precision therapy and outcome. Lung cancer is the leading cause of cancer deaths in the U.S. and around the world. Dr. Sun's focus is on the genetics and epigenetics of lung cancer, cancer genomic abnormalities for targeted therapies and resistance mechanisms of targeted therapies.
- Early cancer detection and diagnosis through DNA methylation markers. Unlike somatic mutations with a low recurrence frequency in most cancers, DNA methylation changes occur more universally. These cancer hallmarks can be detected though tumor-released DNA in blood circulation (cell-free DNA). By mining large pools of genomic data generated both externally and within Mayo Clinic, Dr. Sun applies advanced techniques to identify the most distinguishable universal and site-specific cancer markers for early cancer diagnosis.
- Translational epigenomics. Epigenomics is a new and fascinating field for exploring disease mechanisms, identifying new treatment targets and predicting treatment response. In collaboration with clinicians, Dr. Sun explores the roles of abnormal epigenetic regulation in autoimmune diseases such as Crohn's disease, primary biliary cholangitis and primary sclerosing cholangitis. Genome-wide DNA methylation, open chromatin accessibility through ATAC sequencing and histone modifications through chromatin immunoprecipitation sequencing (ChIP-seq) are being used to untangle the complex interplay of various regulators.
- Large genomics data integration and systems biology. In the current research environment, multiple types of genomic data are frequently generated from next generation sequencing (NGS) technologies for the same set of samples. Integrated analysis of these data is needed, which requires the development of novel algorithms and methods. Dr. Sun is actively working in this area and has published several frequently cited papers on this topic.
- Bioinformatics workflow and method development. NGS data are huge and complex and need efficient algorithms and seamless workflows for analysis. Dr. Sun leads a team to develop workflows for various sequencing data such as DNA methylation sequencing, microRNA sequencing, long noncoding RNA sequencing and RNA sequencing.
Significance to patient care
The identification of genetic or genomic markers will help to diagnose diseases early and potentially prevent their development. A deep understanding of a tumor's genetic makeup will also help treat patients individually for optimal outcomes.
- Member, Editorial board, Epigenomics, 2015-present
- Member, Editorial board, Journal of Computational Biology and Bioinformatics, 2015-present
- Guest associate editor, Frontiers in Genetics, 2017-2018
- Associate editor, World Journal of Respirology, 2016-2018