T Connor, M McPhillips, M Hipwell, A Ziolkowski, C Oldmeadow, M Clapham, P G Pockney, E Lis, T Banasiewicz, A Pławski, R J Scott
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引用次数: 3
Abstract
Background: Familial adenomatous polyposis (FAP) is an autosomal dominant condition that predisposes patients to colorectal cancer. FAP is the result of a loss of APC function due to germline pathogenic variants disrupting gene expression. Genotype-phenotype correlations are described for FAP. For example attenuated forms of the disease are associated with pathogenic variants at the 5' and 3' ends of APC whilst severe forms of the disease appear to be linked to variants occurring in the mutation cluster region (MCR) of the gene. Variants occurring in the MCR are phenotypically associated with hundreds to thousands of adenomas carpeting the colon and rectum and patients harbouring changes in this region have a high propensity to develop colorectal cancer. Not all patients who carry pathogenic variants in this region have severe disease which may be a result of environmental factors. Alternatively, phenotypic variation observed in these patients could be due to modifier genes that either promote or inhibit disease expression. Mouse models of FAP have provided several plausible candidate modifier genes, but very few of these have survived scrutiny. One such genetic modifier that appears to be associated with disease expression is CD36. We previously reported a weak association between a polymorphism in CD36 and a later age of disease onset on a relatively small FAP patient cohort.
Methods: In the current study, we enlarged the FAP cohort. 395 patients all carrying pathogenic variants in APC were tested against three CD36 Single Nucleotide Polymorphisms (SNP)s (rs1049673, rs1761667 rs1984112), to determine if any of them were associated with differences in the age of disease expression.
Results: Overall, there appeared to be a statistically significant difference in the age of disease onset between carriers of the variant rs1984112 and wildtype. Furthermore, test equality of survivor functions for each SNP and mutation group suggested an interaction in the Log Rank, Wilcoxon, and Tarone-Ware methods for rs1049673, rs1761667, and rs1984112, thereby supporting the notion that CD36 modifies disease expression.
Conclusions: This study supports and strengthens our previous findings concerning CD36 and an association with disease onset in FAP, AFAP and FAP-MCR affected individuals. Knowledge about the role CD36 in adenoma development may provide greater insight into the development of colorectal cancer.
期刊介绍:
Hereditary Cancer in Clinical Practice is an open access journal that publishes articles of interest for the cancer genetics community and serves as a discussion forum for the development appropriate healthcare strategies.
Cancer genetics encompasses a wide variety of disciplines and knowledge in the field is rapidly growing, especially as the amount of information linking genetic differences to inherited cancer predispositions continues expanding. With the increased knowledge of genetic variability and how this relates to cancer risk there is a growing demand not only to disseminate this information into clinical practice but also to enable competent debate concerning how such information is managed and what it implies for patient care.
Topics covered by the journal include but are not limited to:
Original research articles on any aspect of inherited predispositions to cancer.
Reviews of inherited cancer predispositions.
Application of molecular and cytogenetic analysis to clinical decision making.
Clinical aspects of the management of hereditary cancers.
Genetic counselling issues associated with cancer genetics.
The role of registries in improving health care of patients with an inherited predisposition to cancer.