RESUMO
Objective The aim of our study was to investigate the influence of hexavalent chromium exposure on mRNA expression of cell cycle related genes in electroplating workers, and to provide population data for investigating the toxic mechanisms of hexavalent chromium. Methods A total of 155 cases of workers occupationally exposed to hexavalent chromium were selected, including 89 males and 66 females, and the average age of workers was 39.65±8.856 years old. Questionnaire was used to collect essential information of workers. Peripheral blood was collected from electroplating workers. The inductively couple plasma mass spectrometry (ICP-MAS) was used to measure total blood chromium content. The workers were divided into four groups according to the blood chromium content. After extracting total RNA from whole blood and reverse transcription, the mRNA expression levels of p16 and CDK6 genes were detected by real-time quantitative PCR. Meanwhile, the levels of blood chromium (BCr) and the mRNA expression of p16 and CDK6 genes were compared among four groups. The impact of BCr, smoking habits, drinking habits, gender on the mRNA expression of CDK6 gene was analyzed. Results The levels of BCr in group 1 to 4 were 0.04ppb, 0.47±0.29 ppb, 2.76±1.16 ppb, 9.36 ±4.38 ppb, respectively, and the difference between every two groups was significant (P<0.05) . The median of p16 gene expression in four groups was 4.22, 7.19, 7.47, and 14.60, respectively, and the difference between every two groups was not significant (P>0.05) . The mRNA expression levels of CDK6 gene in groups 2 to 4 were 15.05, 8.03 and 24.81, respectively, which were significantly higher than that in group 1 (P<0.05) . The results of logistic regression showed that the level of Bcr was the main influence factor, while smoking habits, drinking habits and gender had no obvious impact on the mRNA expression of CDK6 gene. Conclusions Long-term exposure of hexavalent chromium led to higher mRNA expression of CDK6 gene, and it may serve as a biomarker for workers occupationally exposed to hexavalent chromium.
RESUMO
Objective To investigate the effects of asbestos exposure on plasma miRNA expression.Methods Plasma samples were collected from control group and asbestos -exposed group (time of exposure >10 years)and three samples from each group were selected to detect differentially expressed miRNA using LC Sciences miRNA Microarray -Single.The target genes of differential miRNA were predicted by three kinds of online software,Target Scan,miRanda and PicTar.GO term enrichment and KEGG pathways were analyzed.Results The results of microarray indicated that there were 40 differential miRNA expression between exposed and control groups(P <0.05),and the signal value of 9 differential miRNA exceeded 500.After analyzing signal pathways of target genes of 5 miRNA,of which the signal values were over 500,these target genes were found mainly involved in pathways associated with cancer and metabolism,including potential function targets of FAS,TP53 and FGFR3.Conclusion Asbestos exposure can result in differentially expressed miRNA in the plasma from workers occupationally exposed to asbestos and the target genes of these miRNA may play important roles in the pathways of cancer.However,the mechanism of these miRNA in asbestos -related diseases needs to be further studied in the future.