4-Aminobiphenyl suppresses homologous recombination repair by a reactive oxygen species-dependent p53/miR-513a-5p/p53 loop

Abstract 4-Aminobiphenyl (4-ABP), a well-known human carcinogen, can cause oxidative DNA damage and induce miR-513a-5p. However, the interplay between miR-513a-5p and DNA damage remains unclear. In our result of ChIP assay, we speculated that p53 as transcription factor could regulate miR-513a-5p expression. In addition, we found that miR-513a-5p-induced by 4-ABP could suppress p53 expression and HR repair activity. On the other hand, the levels of p53, miR-513a-5p, and γH2AX were attenuated by 5 mM N-acetyl- l -cysteine (NAC) pretreatment, indicating that the reactive oxygen species (ROS)-dependent p53-miR-513a-5p was involved in DSB repair in 4-ABP-treated cells. These findings indicated that the ROS/p53/miR-513a-5p/p53 loop axis plays a relevant role in regulating HR repair which may facilitate our understanding of molecular mechanisms regarding how miR-513a-5p impacts DSB repair in 4-ABP-treated cells.