Abstract
Cancer is essentially a somatic evolutionary process and is, therefore, effectively defined by the genetic and epigenetic changes underlying this process. An understanding of the function of these changes is fundamental to devising new approaches to prevention and treatment. Colorectal cancer (CRC), apart from its obvious importance as one of the most frequent cancers, provides an excellent model for such studies because of the availability of precursor adenoma lesions and the existence of several clear-cut familial inherited susceptibilities. These include familial adenomatous polyposis (FAP), which led to the identification of the APC gene and the importance of the Wnt pathway, and hereditary non-polyposis CRC (HNPCC), which identified the role of the mismatch repair genes in colorectal and other cancers. The presently known range of genetic and epigenetic changes in CRCs and adenomas is reviewed in this paper and the evidence against a requirement for genomic instability presented, together with a discussion of patterns of gene methylation, including especially our work on the homeobox gene, CDX1. Clearly, familial cancers, such as FAP and HNPCC, cannot account for more than perhaps 5% of the incidence of CRC. There is, however, evidence that approximately a further 25–30% have some inherited susceptibility. Based on the association of APC missense variants with multiple adenomas, we proposed that much of this may be due to the cumulative effects of low frequency, low penetrance variants, and the “rare variant hypothesis”. The evidence for this from our work on multiple adenoma cases, and certain other examples, is discussed.
Similar content being viewed by others
Log in or create a free account to read this content
Gain free access to this article, as well as selected content from this journal and more on nature.com
or
References
Bodmer WF (1999) Familial adenomatous polyposis (FAP) and its gene, APC. Cytogenet Cell Genet 86:99–104
Fearnhead NS et al (2001) The ABC of APC. Hum Mol Genet 10(7):721–733
Fearnhead NS, Wilding JL, Bodmer WF (2002) Genetics of colorectal cancer: hereditary aspects and overview of colorectal tumorigenesis. Br Med Bull 64:27–43
Fearnhead NS, Wilding JL, Winney B, Tonks S, Bartlett S, Bicknell DC, Tomlinson IPM, Mortensen NJ, Bodmer WF (2004) Multiple rare variants in different genes account for multifactorial inherited susceptibility to colorectal adenomas. Proc Natl Acad Sci USA 101:15992–15997
Fearnhead NS, Winney B, Bodmer WF (2005) Rare variant hypothesis for multifactorial inheritance: susceptibility to colorectal adenomas as a model. Cell Cycle 4:521–525
Frayling IM, Beck NE, Ilyas M, Dove-Edwin I, Goodman P, Pack K, Bell JA, Williams CB, Hodgson SV, Thomas HJW, Talbot IC, Bodmer WF, Tomlinson IPM (1998) The APC variants I1307K and E1317Q are associated with colorectal tumors, but not always with a family history. Proc Natl Acad Sci USA 95:10722–10727
Frommer M, McDonald LE, Millar DS, Collis CM, Watt F, Grigg GW, Molloy PL, Paul CL (1992) A genomic sequencing protocol that yields a positive display of 5-methylcytosine residues in individual DNA strands. Proc Natl Acad Sci USA 89:1827–1831
Homfray TF et al? (1998) Defects in mismatch repair occur after APC mutations in the pathogenesis of sporadic colorectal tumours. Hum Mutat 11(2):114–120
Laken SJ, Petersen GM, Gruber SB, Oddoux C, Ostrer H, Giardiello FM, Hamilton SR, Hampel H, Markowitz A, Klimstra D, Jhanwar S, Winawer S, Offit K, Luce MC, Kinzler KW, Vogelstein B (1997) Familial colorectal cancer in Ashkenazim due to a hypermutable tract in APC. Nat Genet 17:79–83
Lamlum H, Al Tassan N, Jaeger E et al (2000) Germline APC variants in patients with multiple colorectal adenomas, with evidence for the particular importance of E1317Q. Hum Mol Genet 9(15):2215–2221
Liu Y, Bodmer WF (2006) Analysis of P53 mutations and their expression in 56 colorectal cancer cell lines. Proc Natl Acad Sci USA 103:976–981
Sieber OM, Heinimann K, Gorman P, Lamlum H, Crabtree M, Simpson CA, Davies D, Neale K, Hodgson SV, Roylance RR, Phillips RKS, Bodmer WF, Tomlinson IP (2002) Analysis of chromosomal instability in human colorectal adenomas with two mutational hits at APC. Proc Natl Acad Sci USA 99(26):16910–16915
Tomlinson IP, Bodmer WF (1995) The HLA system and the analysis of multifactorial genetic disease. Trends Genet 11:493-498
Wong NA, Britton MP, Choi GS, Stanton TK, Bicknell DC, Wilding JL, Bodmer WF (2004) Loss of CDX1 expression in colorectal carcinoma: promoter methylation, mutation, and loss of heterozygosity analyses of 37 cell lines. Proc Natl Acad Sci USA 101(2):574–579
Woodford-Richens KL, Rowan AJ, Gorman P, Halford S, Bicknell DC, Wasan HS, Roylance RR, Bodmer WF, Tomlinson IP (2001) SMAD4 mutations in colorectal cancer probably occur before chromosomal instability, but after divergence of the microsatellite instability pathway. Proc Natl Acad Sci USA 98(17):9719–9723
Acknowledgements
I would like to thank all present and former members of my laboratory for their many contributions to the work quoted in this review.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Bodmer, W.F. Cancer genetics: colorectal cancer as a model. J Hum Genet 51, 391–396 (2006). https://doi.org/10.1007/s10038-006-0373-x
Received:
Accepted:
Published:
Issue date:
DOI: https://doi.org/10.1007/s10038-006-0373-x
Keywords
This article is cited by
-
Intestinal microbiota profiles in a genetic model of colon tumorigenesis correlates with colon cancer biomarkers
Scientific Reports (2022)
-
Gender-specific association of NFKBIA promoter polymorphisms with the risk of sporadic colorectal cancer
Medical Oncology (2013)
-
Familial colorectal cancer type X syndrome: two distinct molecular entities?
Familial Cancer (2011)
-
Dermokine as a novel biomarker for early-stage colorectal cancer
Journal of Gastroenterology (2010)
-
Common and rare variants in multifactorial susceptibility to common diseases
Nature Genetics (2008)


