Abstract
We examined the role of miRNAs in DNA damage response in HepG2 cells following exposure to 4-aminobiphenyl (4-ABP). The arylamine 4-ABP is a human carcinogen. Using the Comet assay, we showed that 4-ABP (18.75-300. μM) induces DNA damage in HepG2 cells after 24. h. DNA damage signaling pathway-based PCR arrays were used to investigate expression changes in genes involved in DNA damage response. Results showed down-regulation of 16 DNA repair-related genes in 4-ABP-treated cells. Among them, the expression of selected six genes (UNG, LIG1, EXO1, XRCC2, PCNA, and FANCG) from different DNA repair pathways was decreased with quantitative real-time PCR (qRT-PCR). In parallel, using the miRNA array, we reported that the expression of 27 miRNAs in 4-ABP-treated cells was at least 3-fold higher than that in the control group. Of these differential 27 miRNAs, the most significant expression of miRNA-513a-5p and miRNA-630 was further validated by qRT-PCR, and was predicted to be implicated in the deregulation of FANCG and RAD18 genes, respectively, via bioinformatic analysis. Both FANCG and RAD18 proteins were found to be down-regulated in 4-ABP-treated cells. In addition, overexpression and knockdown of miRNA-513a-5p and miRNA-630 reduced and increased the expression of FANCG and RAD18 proteins, respectively.Based on the above results, we indicated that miRNA-513a-5p and miRNA-630 could play a role in the suppression of DNA repair genes, and eventually lead to DNA damage.
Original language | English |
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Pages (from-to) | 69-77 |
Number of pages | 9 |
Journal | Toxicology |
Volume | 322 |
DOIs | |
State | Published - 1 Aug 2014 |
Keywords
- DNA damage
- DNA repair
- MiRNA-513a-5p
- MiRNA-630