Variants of the adiponectin (ADIPOQ) and adiponectin receptor 1 (ADIPOR1) genes and colorectal cancer risk.
BACKGROUND
Current epidemiological evidence suggests an association between obesity, hyperinsulinemia, and colorectal cancer risk. Adiponectin is a hormone secreted by the adipose tissue, and serum levels are inversely correlated with obesity and hyperinsulinemia. While there is evidence of an association between circulating adiponectin levels and colorectal cancer risk, no association between genes of the adiponectin pathway and colorectal cancer have been reported to date.


OBJECTIVE
To determine the association of 10 haplotype-tagging single-nucleotide polymorphisms (SNPs) of the adiponectin (ADIPOQ) and adiponectin receptor 1 (ADIPOR1) genes with colorectal cancer risk.


METHODS
Two case-control studies including patients with a diagnosis of colorectal cancer and controls were recruited between 2000 and 2007. Case-control study 1 included a total of 441 patients with a diagnosis of colorectal cancer and 658 controls; both groups were of Ashkenazi Jewish ancestry and from New York, New York. Case-control study 2 included 199 patients with a diagnosis of colorectal cancer and 199 controls from Chicago, Illinois, matched 1:1 for sex, age, and ethnicity.


METHODS
ADIPOQ and ADIPOR1 SNP frequency among cases and controls.


RESULTS
In study 1, after adjustment for age, sex, and SNPs from the same gene, 3 ADIPOQ SNPs and 1 ADIPOR1 SNP were associated with colorectal cancer risk: rs266729 (adjusted odds ratio [AOR], 0.72; 95% confidence interval [CI], 0.55-0.95) and rs822396 (AOR, 0.37; 95% CI, 0.14-1.00) were associated with decreased risk whereas rs822395 (AOR, 1.76; 95% CI, 1.09-2.84) and rs1342387 (AOR, 1.79; 95% CI, 1.18-2.72) were associated with increased risk. In study 2, after adjustment for age, sex, race, and SNPs from the same gene, the ADIPOQ SNP rs266729 was associated with a decreased colorectal cancer risk of similar magnitude as in study 1 (AOR, 0.52; 95% CI, 0.34-0.78). Combined analysis of both studies shows an association of rs266729 with decreased colorectal cancer risk (AOR, 0.73; 95% CI, 0.53-0.99).


CONCLUSIONS
The SNP rs266729, which tags the 5' flanking region of the ADIPOQ gene, is associated with decreased colorectal cancer risk.
Kaklamani
Virginia G
VG
Cancer Genetics Program, Division of Hematology and Oncology, Department of Medicine and Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.
Wisinski
Kari B
KB
Sadim
Maureen
M
Gulden
Cassandra
C
Do
Albert
A
Offit
Kenneth
K
Baron
John A
JA
Ahsan
Habibul
H
Mantzoros
Christos
C
Pasche
Boris
B
D024506:5' Flanking Region; D052242:Adiponectin / Q000235:genetics*; D000328:Adult; D000368:Aged; D001483:Base Sequence; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D006801:Humans; D007585:Jews / Q000235:genetics; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D020641:Polymorphism, Single Nucleotide; D054419:Receptors, Adiponectin / Q000235:genetics*; D012307:Risk Factors
C475418:ADIPOR1 protein, human; D052242:Adiponectin; D054419:Receptors, Adiponectin