Objective To study the correlation between urinary nickel and methylation of anti-oncogene p15 and p16 in blood DNA of workers exposed to nickel.
Methods Totally 165 nickel exposed workers and 65 water treatment workers without occupational nickel exposure were recruited in this study. The levels of urinary nickel were determined by dimethylglyoxime spectrophotometry. Methylation specific polymerase chain reaction (MSP) was used to detect the methylation of p15 and p16 in blood DNA.
Results The median concentrations of urinary nickel in steel refining workers (5.34 μg/L), slaggers (4.59 μg/L) and mill men (4.52 μg/L) were significantly higher than that in the controls (1.78 μg/L) (P<0.01). The methylation rate of p15 in the exposed group (24.55%) was significantly higher than that in the control group (11.94%) (P0.023). However, no significant difference in the methylation rate of p16 between the exposed group (21.82%) and the control group (11.94%) was found (P0.082). The multivariate logistic analysis showed that workers bearing higher urinary nickel levels were at higher risks of developing p15 methylation (OR=1.47, P0.024).
Conclusion The level of urinary nickel is significantly correlated with the methylation of p15 in blood DNA.
DownLoad: