Adiponectin gene polymorphisms and obesity increase the susceptibility to arsenic-related renal cell carcinoma

Our recent study found that high urinary total arsenic levels were associated with renal cell carcinoma (RCC). Recent studies demonstrated that low circulating adiponectin was related to RCC. The aim of the present study was to explore the relationship between adiponectin gene (ADIPOQ) polymorphisms and RCC and investigate whether individuals with an ADIPOQ risk genotype, obesity, and high urinary total arsenic levels have a modified odds ratio (OR) of RCC. A total of 389 RCC patients and 389 age- and sex-matched controls were recruited between November 2006 and December 2012 in Taiwan. Image-guided biopsy or surgical resection of renal tumors was performed to pathologically verify RCC. Genomic DNA was used to examine the genotypes of the ADIPOQ rs182052, ADIPOQ rs2241766, ADIPOQ rs1501299, and ADIPOQ rs1063539 SNPs by PCR-RFLP. HPLC-HG-AAS was used to measure the concentrations of urinary arsenic species. Participants with the ADIPOQ rs182052 G/A+A/A genotype had a significantly higher OR of RCC compared with those with the ADIPOQ rs182052 G/G genotype. The OR (95% confidence interval [CI]) was 1.70 (1.23-2.36). The OR of RCC for the combined effect of high urinary total arsenic levels and obesity, which was dose-dependent, in individuals with the ADIPOQ rs182052 G/A+A/A genotype was 9.33 (3.85-22.62). The present study found significant combined effects of obesity and the ADIPOQ rs182052 G/A+A/A genotype on the arsenic-related risk of RCC in a population with low arsenic exposure. Arsenic exposure, obesity, and the ADIPOQ rs182052 polymorphism could be predictors of a higher OR of RCC.