Lack of association between insulin receptor substrate2 rs1805097 polymorphism and the risk of colorectal and breast cancer: a meta-analysis.
BACKGROUND
Insulin receptor substrate-2 (IRS-2), a signaling adaptor protein, was involved in two cancer-related pathways (the phosphatidylinositol 3'-kinase (PI3K) and the extracellular signal-regulated kinase (ERK) pathways). Several studies have evaluated the association between IRS2 rs1805097 (G>A) polymorphisms and the risk of colorectal and breast cancer. However, the results were inconsistent.


RESULTS
A meta-analysis of seven published case-control studies (4 studies with 4798 cases and 5478 controls for colorectal cancer and 3 studies with 2108 cases and 2507 controls for breast cancer) were conducted to assess the strength of association using crude odd ratios (ORs) with 95% confidence intervals (CIs). For colorectal cancer, no obvious associations were found for all genetic models (homozygote comparison OR = 0.96, 95%CI 0.85-1.08, Pheterogeneity = 0.97; heterozygote comparison: OR = 0.91, 95%CI 0.73-1.13, Pheterogeneity<0.01; dominant model: OR = 0.92, 95%CI 0.80-1.06, Pheterogeneity = 0.05; recessive model: OR = 1.02, 95%CI 0.91-1.14, Pheterogeneity = 0.60). In the subgroup analysis by ethnicity, control source and consistency of frequency with Hardy-Weinberg equilibrium (HWE), still no significant associations were observed. For breast cancer, also no obvious associations were found for all genetic models (homozygote comparison: OR = 0.95, 95%CI 0.71-1.26, Pheterogeneity = 0.10; heterozygote comparison: OR = 1.00, 95%CI 0.89-1.14, Pheterogeneity = 0.71; dominant model: OR = 0.98, 95%CI 0.87-1.10, Pheterogeneity = 0.55; recessive model: OR = 0.95, 95%CI 0.72-1.25, Pheterogeneity = 0.07). We performed subgroup analyses by sample size and did not find an association.


CONCLUSIONS
This meta-analysis indicated that IRS2 rs1805097 polymorphism was not associated with colorectal and breast cancer risk.
Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Yue
Y
Hu
Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Min
M
Zhou
Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Kai
K
Zhang
Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Xiangquan
X
Kong
Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Xiaoyan
X
Hu
Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Kang
K
Li
Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Li
L
Liu
D001943:Breast Neoplasms / Q000235:genetics*; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000235:genetics*; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D055504:Insulin Receptor Substrate Proteins / Q000235:genetics*; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors
C526297:IRS2 protein, human; D055504:Insulin Receptor Substrate Proteins