Relationship Between Urinary Nickel and Methylation of p15, p16 in Workers Exposed to Nickel

OBJECTIVE:The purpose of this study was to investigate the relationship between urinary nickel and methylation of p15, p16 in workers exposed to nickel. METHODS:In this study, 165 nickel-exposed workers and 67 workers without exposure were recruited. The levels of urinary nickel were analyzed using dimethylglyoxime spectrophotometric method. Methylation–specific polymerase chain reaction was used to detect the methylation of p15 and p16. RESULTS:The median concentration of urinary nickel in the exposed group (4.58 μg/L) was significantly higher than that in the control group (1.78 μg/L; P < 0.01). The rate of methylation of p15 in the exposed group was significantly higher than that in the control group (P = 0.023). The multiple logistic analysis showed that workers having higher urinary nickel were at the higher risk of methylation of p15 (P = 0.024). CONCLUSIONS:The levels of urinary nickel were significantly associated with the methylation of p15.