Appraising the relevance of DNA copy number loss and gain in prostate cancer using whole genome DNA sequence data
PLOS GENETICS
Authors: Camacho, Niedzica; Van Loo, Peter; Edwards, Sandra; Kay, Jonathan D.; Matthews, Lucy; Haase, Kerstin; Clark, Jeremy; Dennis, Nening; Thomas, Sarah; Kremeyer, Barbara; Zamora, Jorge; Butler, Adam P.; Gundem, Gunes; Merson, Sue; Luxton, Hayley; Hawkins, Steve; Ghori, Mohammed; Marsden, Luke; Lambert, Adam; Karaszi, Katalin; Pelvender, Gill; Massie, Charlie E.; Kote-Jarai, ZSofia; Raine, Keiran; Jones, David; Howat, William J.; Hazell, Steven; Livni, Naomi; Fisher, Cyril; Ogden, Christopher; Kumar, Pardee; Thompson, Alan; Nicol, David; Mayer, Erik; Dudderidge, Tim; Yu, Yongwei; Zhang, Hongwei; Shah, Nimish C.; Gnanapragasam, Vincent J.; Isaacs, William; Visakorpi, Tapio; Hamdy, Freddie; Berney, Dan; Verri, Clare; Warren, Anne Y.; Wedge, David C.; Lynch, Andrew G.; Foster, Christopher S.; Lu, Yong Jie; Bova, G. Steven; Whitaker, Hayley C.; McDermott, Ultan; Neal, David E.; Eeles, Rosalind; Coope, Colin S.; Brewer, Daniel S.
Abstract
A variety of models have been proposed to explain regions of recurrent somatic copy number alteration (SCNA) in human cancer. Our study employs Whole Genome DNA Sequence (WGS) data from tumor samples (n = 103) to comprehensively assess the role of the Knudson two hit genetic model in SCNA generation in prostate cancer. 64 recurrent regions of loss and gain were detected, of which 28 were novel, including regions of loss with more than 15% frequency at Chr4p15.2-p15.1 (15.53%), Chr6q27 (16.50%) and Chr18q12.3 (17.48%). Comprehensive mutation screens of genes, lincRNA encoding sequences, control regions and conserved domains within SCNAs demonstrated that a two-hit genetic model was supported in only a minor proportion of recurrent SCNA losses examined (15/40). We found that recurrent breakpoints and regions of inversion often occur within Knudson model SCNAs, leading to the identification of ZNF292 as a target gene for the deletion at 6q14.3-q15 and NKX3.1 as a two-hit target at 8p21.3-p21.2. The importance of alterations of lincRNA sequences was illustrated by the identification of a novel mutational hotspot at the KCCAT42, FENDRR, CAT1886 and STCAT2 loci at the 16q23.1-q24.3 loss. Our data confirm that the burden of SCNAs is predictive of biochemical recurrence, define nine individual regions that are associated with relapse, and highlight the possible importance of ion channel and G-protein coupled-receptor (GPCR) pathways in cancer development. We concluded that a two-hit genetic model accounts for about one third of SCNA indicating that mechanisms, such haploinsufficiency and epigenetic inactivation, account for the remaining SCNA losses.
Gene expression analysis for the identification of genes involved in early tumour development
ICCS 2007
Authors: Forte, Stefano; Scarpulla, Salvatore; Lagana, Alessandro; Memeo, Lorenzo; Gulisano, Massimo
Abstract
Prostatic tissues can undergo to cancer insurgence and prostate cancer is one of the most common types of malignancies affecting adult men in the United States. Primary adenocarcinoma of the seminal vesi-cles (SVCA) is a very rare neoplasm with only 48 histologically confirmed cases reported in the European and United States literature. Prostatic tissues, seminal vesicles and epididymis belongs all to the same microenvironment, shows a very close morphology and share the same embryological origin. Despite these common features the rate of cancer occurrence is very different. The understanding of molecular differences between non neoplastic prostatic tissues and non neoplastic epididymis or seminal vesicles may suggest potential mechanisms of resistance to tumour occurrence. The comparison of expression patterns of non neoplastic prostatic and seminal vesicles tissues to identify differentially expressed genes can help researchers in the identification of biological actors involved in the early stages of the tumour development.