[Changes in mRNA expression of p53 and related downstream genes in peripheral blood lymphocytes in workers occupationally exposed to arsenic].
OBJECTIVE
To investigate the changes in mRNA expression of p53 and related downstream genes in peripheral blood lymphocytes in workers occupationally exposed to arsenic as well as its influencing factors, and to analyze the mechanism of genetic toxicity of arsenic.


METHODS
With cluster random sampling, 79 workers from an arsenic smelting plant were selected as exposure group, and another 24 people without occupational exposure to arsenic were selected as control group. The relative mRNA expression of p53 and related downstream genes in the peripheral blood lymphocytes of the two groups was determined by quantitative realtime PCR. The levels of inorganic arsenic (iAs), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) in urine were determined by hydride generation-atomic absorption spectrometry.


RESULTS
The exposure group had significantly higher levels of iAs, MMA, and DMA than the control group (P<0.01); the exposure group had significantly higher relative mRNA expression (2(-ΔΔCt)) of p53 and four related downstream genes in peripheral blood lymphocytes than the control group (P<0.05); the relative mRNA expression of p53 and related downstream genes was positively correlated with each other (P<0.01), with a correlation coefficient greater than 0.4; the levels of arsenic compounds in urine were positively correlated with the relative mRNA expression of p53 and some of its downstream genes (P<0.05).


CONCLUSIONS
The changes in mRNA expression of p53 and related downstream genes are closely related to the metabolic transformation of inorganic arsenic in workers occupationally exposed to arsenic, and it also plays an important role in genetic toxicity and carcinogenic effect in people exposed to arsenic.
Yunnan Provincial Center for Disease Control and Prevention, Kunming 650022, China.
Weihua
W
Wen
Ying
Y
Li
Huirong
H
Cheng
Pan
P
Wang
Yanhong
Y
Tang
D001151:Arsenic / Q000009:adverse effects* / Q000652:urine; D001152:Arsenicals / Q000652:urine; D002101:Cacodylic Acid / Q000652:urine; D016022:Case-Control Studies; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects*; D016273:Occupational Exposure; D012333:RNA, Messenger / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
D001152:Arsenicals; D012333:RNA, Messenger; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D002101:Cacodylic Acid; C020300:monomethylarsonic acid; D001151:Arsenic