Institute of Toxicology, College of Preventive Medicine, Third Military Medical University (Army Medical University), Chongqing, China.
School of Public Healthy and Management, Ningxia Medical University, Yinchuan, China.
J Appl Toxicol. 2022 Mar;42(3):475-489. doi: 10.1002/jat.4233. Epub 2021 Sep 24.
Aflatoxin is a secondary metabolite secreted by Aspergillus flavus, parasitic Aspergillus, and other fungi through the polyketone pathway, and it can be detected in many foods. Aflatoxin has strong toxicity and carcinogenicity, and many studies have shown that aflatoxin is highly associated with liver cancer. In the present study, malignant transformation of L02 cells was induced by aflatoxin B1 (AFB1), and the gene expression, miRNA expression, and methylation level were detected by high-throughput sequencing. The gene and miRNA expression results showed that 2547 genes and 315 miRNAs were changed in the AFB1-treated group compared with the DMSO group. Among them, RSAD2 and SCIN were significantly upregulated, whereas TRAPPC3L and UBE2L6 were significantly downregulated. Has-miR-33b-3p was significantly upregulated, whereas Has-miR-3613-5p was significantly downregulated. The methylation results showed that 2832 CpG sites were methylated on the promoter or coding DNA sequence (CDS) of the gene, whereas the expression of DNMT3a and DNMT3b was significantly upregulated. Moreover, hypermethylation occurred in TRAPPC3L, CDH13, and SPINK13. The results of GO and KEGG pathway analyses showed that significantly changed genes and miRNAs were mainly involved in tumor formation, proliferation, invasion, and migration. The results of network map analysis showed that Hsa-miR-3613-5p, Hsa-miR-615-5p, Hsa-miR-615-3p, and Hsa-miR-3158-3p were the key miRNAs for malignant transformation of L02 cells induced by AFB1. In addition, the expression of ONECUT2, RAP1GAP2, and FSTL4 was regulated by DNA methylation and miRNAs. These results suggested that the gene expression network regulated by DNA methylation and miRNAs may play a vital role in AFB1-induced hepatocellular carcinoma.
黄曲霉毒素是一种由黄曲霉、寄生曲霉和其他真菌通过聚酮途径分泌的次级代谢产物，可以在许多食物中检测到。黄曲霉毒素具有很强的毒性和致癌性，许多研究表明黄曲霉毒素与肝癌高度相关。在本研究中，用黄曲霉毒素 B1（AFB1）诱导 L02 细胞恶性转化，通过高通量测序检测基因表达、miRNA 表达和甲基化水平。基因和 miRNA 表达结果显示，与 DMSO 组相比，AFB1 处理组有 2547 个基因和 315 个 miRNA 发生变化。其中，RSAD2 和 SCIN 显著上调，而 TRAPPC3L 和 UBE2L6 显著下调。Has-miR-33b-3p 显著上调，而 Has-miR-3613-5p 显著下调。甲基化结果显示，基因启动子或编码 DNA 序列（CDS）上有 2832 个 CpG 位点发生甲基化，而 DNMT3a 和 DNMT3b 的表达显著上调。此外，TRAPPC3L、CDH13 和 SPINK13 发生超甲基化。GO 和 KEGG 通路分析结果表明，显著改变的基因和 miRNA 主要参与肿瘤形成、增殖、侵袭和迁移。网络图分析结果显示，Hsa-miR-3613-5p、Hsa-miR-615-5p、Hsa-miR-615-3p 和 Hsa-miR-3158-3p 是 AFB1 诱导 L02 细胞恶性转化的关键 miRNA。此外，ONECUT2、RAP1GAP2 和 FSTL4 的表达受 DNA 甲基化和 miRNA 调控。这些结果表明，DNA 甲基化和 miRNA 调控的基因表达网络可能在 AFB1 诱导的肝癌中发挥重要作用。
