Poster Presentation NSW State Cancer Conference 2023

Alterations in the epigenetic machinery associated with prostate cancer health disparities (#110)

Jenna Craddock 1 , Jue Jiang 2 , Sean M. Patrick 1 , Shingai B.A. Mutambirwa 3 , Phillip D. Stricker 4 , Riana M.S. Bornman 1 , Weerachai Jaratlerdsiri 2 , Vanessa M. Hayes 1 2 5
  1. School of Health Systems and Public Health, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa
  2. Ancestry and Health Genomics Laboratory, Charles Perkins Centre, School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, Australia
  3. Department of Urology, Sefako Makgatho Health Science University, Dr George Mukhari Academic Hospital, Ga-Rankuwa, South Africa
  4. Department of Urology, St. Vincent’s Hospital, Darlinghurst, Australia
  5. Manchester Cancer Research Centre, University of Manchester, Manchester M20 4GJ, United Kingdom

Prostate cancer is driven by acquired genetic alterations, including those impacting the epigenetic machinery. With African ancestry a significant risk factor for aggressive disease, we hypothesize that dysregulation among the roughly 656 epigenetic genes may contribute to prostate cancer health disparities. Interrogating prostate tumor genomic data from 109 men of southern African and 56 men of European Australian ancestry, we found African-derived tumors to present with a longer tail of epigenetic driver gene candidates (72 versus 10). Biased towards African-specific drivers (63 versus 9 shared), many are novel to prostate cancer (18/63) including several putative therapeutic targets (CHD7, DPF3, POLR1B, SETD1B, UBTF and VPS72). Through clustering of all variant types and copy number alterations, we describe two epigenetic PCa taxonomies capable of differentiating patients by ancestry and predicted clinical outcomes. We identified top genes in African and European-derived tumors that represent a multifunctional “generic machinery”, alteration to which may be instrumental in epigenetic dysregulation and prostate tumorigenesis. In conclusion, numerous somatic alterations in the epigenetic machinery drive prostate carcinogenesis but African-derived tumors appear to achieve this with greater diversity amongst such alterations. The greater novelty observed in African-derived tumors illustrates the significant clinical benefit to be derived from a much needed African tailored approach to prostate cancer healthcare aimed at reducing prostate cancer health disparities.