Arsenic Methylation Capability, Myeloperoxidase and Sulfotransferase Genetic Polymorphisms, and the Stage and Grade of Urothelial Carcinoma

Arsenic exposure is associated with an increased risk of bladder cancer. To explore the distribution of the arsenic methylation capability and myeloperoxidase <i>(MPO)</i> and sulfotransferase <i>(SULT) 1A1</i> genotypes in patients at different stages and grades of urothelial carcinoma (UC), 112 UC cases were recruited between September 2002 and May 2004 for this study. Urinary arsenic species, including inorganic arsenic (As^III + As^V), monomethylarsonic acid, and dimethylarsinic acid, were determined with a high-performance liquid chromatography-linked hydride generator and atomic absorption spectrometry. The <i>MPO</i> and <i>SULT1A1</i> genotypes were examined with polymerase chain reaction and restriction fragment length polymorphism. Differential effects of the arsenic methylation capability were found among patients with different stages of UC; however, urinary arsenic concentrations were borderline significantly increased with the progress of UC patients regardless of whether or not they had been exposed to arsenic from drinking water. The <i>MPO</i> and <i>SULT</i> genetic polymorphisms might modify the arsenic methylation profile and UC progression, and thus are worthy of further investigation.