Y.S. Robert Cheng, D.V.M., Ph.D.
Dr. Cheng's research focuses on identifying the early epigenetic changes that may contribute to cancer risk in a DMBA-induced rat mammary gland cancer model. He is using global RNA expression fingerprint profiling during the early stage of breast cancer development and comparing this data to results from parallel epigenetic studies. Dr. Cheng is also interested in elucidation of the mechanistic role of both phase I and II detoxification enzymes in this cancer model.
Toxicogenomic, Epigenetic and Carcinogenesis
Current projects are focused on (1) the identification of early epigenetic changes that would likely contributed to the cancer risk in our DMBA-induced rat mammary gland cancer model; (2) global RNA expression fingerprint profiling during the early stage of breast cancer development and compare them to the parallel epigenetic study results; (3) the elucidation of the mechanistic role of both Phase I & II detoxification enzymes in the rat mammary gland cancer model.
For the epigenetic studies, Dr. Cheng is using one of the global methylation profiling techniques, Methylation Sensitive Restriction Fingerprinting (MSRF) Differential Display Polymerase Chain Reaction (DD-PCR) approach to identify both hypermethylated and hypomethylated genes. Candidates bands are sub-cloned, sequenced and then identified by gene database search. Potential gene targets will be further characterized by bisulfite genomic sequencing and quantitative real time PCR. Dr. Cheng is using the microarray approach for the high throughput gene expression profiling. All microarray data will be explored with various non-supervised clustering algorithms. Data obtained from consistently clustered dendrograms will be exported for downstream pathway and gene ontology analysis. Quantitative real time PCR and various enzyme activity assays will be used to elucidate how the Phase I & 2 genes/enzymes reacted to xenobiotics. EROD assay will also be used to measure the activity of Cytochrome P450.
Synthesis and chemical and biological comparison of nitroxyl- and nitric oxide-releasing diazeniumdiolate-based aspirin derivatives.J. Med. Chem.. 56: 7804-20, 2013. [ Journal Article ]
Dithiolethiones inhibit NF-?B activity via covalent modification in human estrogen receptor-negative breast cancer.Cancer Res.. 72: 2394-404, 2012. [ Journal Article ]
Ets-1 is a transcriptional mediator of oncogenic nitric oxide signaling in estrogen receptor-negative breast cancer.Breast Cancer Res.. 14: R125, 2012. [ Journal Article ]
- Environ. Mol. Mutagen.. 55: 244-55, 2014. [ Journal Article ]
Molecular pathways: toll-like receptors in the tumor microenvironment--poor prognosis or new therapeutic opportunity.Clin. Cancer Res.. 19: 1340-6, 2013. [ Journal Article ]
Dr. Cheng received his Veterinary Medicine degree from the National Taiwan University and his Ph.D. degree (in Cancer Biology) from the University of Hong Kong. Dr. Cheng is a board registered Veterinary Surgeon in Hong Kong and an Active Member of the American Association for Cancer Research. He has done his postdoctoral researches in the University of Hong Kong and the National Cancer Institute at Frederick before he joined the University of Massachusetts Medical School as a Research Assistant Professor. In 2006, Dr. Cheng left the Medical College of the University of Cincinnati and re-joined the National Cancer Institute as a Staff Scientist.