Effect of sodium arsenite to the level of twenty genes expression

Objective: Study the level of 20 genes expression related with arsenic (sodium arsenite). Methods: First, 20 related genes were selected according to the mechanism of arsenism having reported and two control groups were set up. Then, the probs (23～30 mer) and arrays of oligonucleotide were made. Second, human hepatic cells (L 02) were cultured for two weeks exposing different arsenic concentrations, and total RNA was extracted, mRNA purificated, first strand cDNA synthesized, cDNA labelled using Cy\+5 and Cy\+3, cDNA broken using DNA enzyme, then cDNA and the probs hybridized and fluorescence signal scanned. Last, the values of Cy\+5: Cy\+3 were calculated to decide the level of those genes expression. Results: As compared with control, in 0.5 μM and 2.0 μM sodium arsenite groups, expression of C myc, ARS and CTF genes were inhibited, in 2.0 μM,expression of HGF gene was inhibited, but the expression of p53 gene was induced. Conclusion: Arsenic can inhibit the expression of CTF gene, starting of gene transcript was blocked, so it can cause the expression of many of genes to be declined. This result may be ones of the mechanisms of arsenical genetic toxicity.