Cyclin D1 (CCND1) is a key cell cycle regulatory protein. Overexpression of this is often found in tumors, and it is associated with cell proliferation and poor prognosis.
A common adenine-to-guanine substitution polymorphism (A870G) in the CCND1 gene results in an altered messenger RNA transcript and a longer-life protein. These are preferentially encoded by the A allele.
In this study, investigators from Hawaii, USA, tested the overall and stage-specific associations of the CCND1 870A allele with colorectal cancer.
|The association was significant in participants of white or Hawaiian ethnicity.|
|Journal of the American Medical Association|
They performed a population-based case-control study, between 1994 and 1998.
The team included 504 patients with incident colorectal cancer and 624 population-based participants. Participation rates were 58% for cases and 52% for controls.
The investigators recorded ethnicity, gene-dosage effects, and stage and subsite of cancer.
They calculated that the odds ratios for the CCND1 870 GA and AA genotypes, compared with the GG genotype, were 1.2 and 1.5, respectively.
The risk estimates were significantly greater for patients diagnosed at regional or distant stages, compared with patients diagnosed at an earlier stage.
The team found that the association between the A allele and advanced colorectal cancer was significant in participants of white or Hawaiian ethnicity, but not Japanese. The association was stronger for rectal cancer.
Dr Loïc Le Marchand's team concluded, "The CCND1 870A allele may be associated with colorectal cancer, and particularly with forms of the disease that result in severe morbidity and mortality".