Arsenic methylation capability, heme oxygenase-1 and NADPH quinone oxidoreductase-1 genetic polymorphisms and the stage and grade of urothelial carcinomas.
BACKGROUND
Arsenic exposure is associated with an increased risk of urothelial carcinoma (UC). To explore the distribution of the arsenic methylation capability in patients with different stages and grades of UCs, 100 UC cases were recruited between September 2002 and May 2004 for this study.


METHODS
Urinary arsenic species, including inorganic arsenic (As(III) + As(V)), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA), were determined with a high-performance liquid chromatography-linked hydride generator and atomic absorption spectrometry. Determining the percentages of various arsenic species among the total urinary arsenic amount assessed the arsenic methylation capability. The primary methylation index (PMI) was defined as the ratio between MMA and inorganic arsenic. The secondary methylation index (SMI) was determined as the ratio between DMA and MMA.


RESULTS
Differential effects of the arsenic methylation capability were found among patients with different stages of UCs; however, none was found among different grades.


CONCLUSIONS
A significantly different distribution of the HO-1 genotype was found in subjects with different-stage UCs; however, it was not related to the NAD(P)H:quinone oxidoreductase 1 genotype.
Huang
Steven K
SK
Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan.
Chiu
Allen Wen-Hsiang
AW
Pu
Yeong-Shiau
YS
Huang
Yung-Kai
YK
Chung
Chi-Jung
CJ
Tsai
Hui-Ju
HJ
Yang
Mo-Hsiung
MH
Chen
Chien-Jen
CJ
Hsueh
Yu-Mei
YM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001151:Arsenic / Q000009:adverse effects*; D020261:Arsenic Poisoning / Q000150:complications; D002295:Carcinoma, Transitional Cell / Q000139:chemically induced / Q000453:epidemiology / Q000235:genetics / Q000473:pathology*; D015331:Cohort Studies; D019175:DNA Methylation; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009247:NADH, NADPH Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D009367:Neoplasm Staging; D011110:Polymorphism, Genetic; D011336:Probability; D011379:Prognosis; D018570:Risk Assessment; D016019:Survival Analysis; D013624:Taiwan / Q000453:epidemiology; D001749:Urinary Bladder Neoplasms / Q000139:chemically induced / Q000453:epidemiology / Q000235:genetics / Q000473:pathology*
D009247:NADH, NADPH Oxidoreductases; D001151:Arsenic