The focus of this Research Project, originally funded May 1, 1996, renewed June 1, 2002, and renewed again April 1, 2004, has been the role of CpG island hypermethylation changes targeting GSTP1, encoding the p-class glutathione S-transferase, in the pathogenesis of prostate cancer (PCA). Since its inception, Project studies have resulted in 35 peer-reviewed manuscripts (16 since the last competitive renewal) and 19 review articles published, as well as in major new insights into how PCAs likely arise. Specifically, the discovery from this Project that the most common somatic genome alteration yet described for prostate cancer, hypermethylation of the GSTP1 CpG island, appears first in proliferative inflammatory atrophy lesions, prostate cancer precursors that arise in response to inflammatory damage to the prostatic epithelium, has stimulated intense interest in the role of chronic or recurrent inflammation in prostatic carcinogenesis. For the next funding period, the major hypothesis to be addressed is that somatic CpG island hypermethylation changes, at GSTP1 and at other gene loci, arise in an inflammatory milieu as a result of increased expression and/or activity of DNMTs. Provocative preliminary data hint that reactive nitrogen species, elaborated by inflammatory cells, may drive DNA methylation by a direct effect on DNA methyltransferase function. To test this new mechanism, three Specific Aims are proposed: (1) a characterization of post-translational modifications of DNMTs, including S-nitrosation in response to nitric oxide exposure, which promote de novo DNA methylation, (2) an evaluation of genome-wide differences in DNA methylation and chromatin structure in normal and neoplastic prostate cells, and the effects of nitric oxide exposure on patterns of genome DNA methylation, and (3) an assessment of the effects of chronic inflammation on prostatic carcinogenesis in Gstp1/2+/+ versus Gstp1/2-/- mice, and on de novo GSTP1 hypermethylation in Gstp1/2-/-GSTP1+ mice.

Public Health Relevance

Prostate cancer is the most common serious cancer diagnosed in men in the United States, and a leading cause of cancer mortality. This proposal is focused on ascertaining the cause of the disease, providing the basis for its prevention.

National Institute of Health (NIH)
National Cancer Institute (NCI)
Research Project (R01)
Project #
Application #
Study Section
Cancer Etiology Study Section (CE)
Program Officer
Okano, Paul
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Johns Hopkins University
Internal Medicine/Medicine
Schools of Medicine
United States
Zip Code
Aryee, Martin J; Liu, Wennuan; Engelmann, Julia C et al. (2013) DNA methylation alterations exhibit intraindividual stability and interindividual heterogeneity in prostate cancer metastases. Sci Transl Med 5:169ra10
Haffner, Michael C; Pellakuru, Laxmi G; Ghosh, Susmita et al. (2013) Tight correlation of 5-hydroxymethylcytosine and Polycomb marks in health and disease. Cell Cycle 12:1835-41
Shinohara, Debika Biswal; Vaghasia, Ajay M; Yu, Shu-Han et al. (2013) A mouse model of chronic prostatic inflammation using a human prostate cancer-derived isolate of Propionibacterium acnes. Prostate 73:1007-15
Weier, Christopher; Haffner, Michael C; Mosbruger, Timothy et al. (2013) Nucleotide resolution analysis of TMPRSS2 and ERG rearrangements in prostate cancer. J Pathol 230:174-83
Yegnasubramanian, Srinivasan; Wu, Zhijin; Haffner, Michael C et al. (2011) Chromosome-wide mapping of DNA methylation patterns in normal and malignant prostate cells reveals pervasive methylation of gene-associated and conserved intergenic sequences. BMC Genomics 12:313
Lin, Jianqing; Haffner, Michael C; Zhang, Yonggang et al. (2011) Disulfiram is a DNA demethylating agent and inhibits prostate cancer cell growth. Prostate 71:333-43
Vaughn, Matthew P; Biswal Shinohara, Debika; Castagna, Nicole et al. (2011) Humanizing ?-class glutathione S-transferase regulation in a mouse model alters liver toxicity in response to acetaminophen overdose. PLoS One 6:e25707
Haffner, Michael C; Chaux, Alcides; Meeker, Alan K et al. (2011) Global 5-hydroxymethylcytosine content is significantly reduced in tissue stem/progenitor cell compartments and in human cancers. Oncotarget 2:627-37
Nelson, William G; De Marzo, Angelo M; Yegnasubramanian, Srinivasan (2009) Epigenetic alterations in human prostate cancers. Endocrinology 150:3991-4002
Bastian, Patrick J; Palapattu, Ganesh S; Yegnasubramanian, Srinivasan et al. (2008) CpG island hypermethylation profile in the serum of men with clinically localized and hormone refractory metastatic prostate cancer. J Urol 179:529-34;discussion 534-5

Showing the most recent 10 out of 21 publications