Transcriptome analysis to identify the Ras and Rap1 signal pathway genes involved in the response of TM3 Leydig cells exposed to zearalenone.

The mechanism of action of zearalenone (ZEA) in inducing germ cell tumors is unclear, and little is known about the change in the transcriptome of germ cells after ZEA exposure. To explore the molecular basis of the ZEA oncogene, we examined the median lethal concentration (50 μmol/L) and pro-apoptotic effect of ZEA on TM3 Leydig cells by MTT and TUNEL assay. Subsequently, we investigated the genetic changes in the transcriptome of TM3 Leydig cells exposed to 50 μmol/L ZEA. The transcriptome sequencing results show that 772 genes are significantly down-regulated, while 204 genes are significantly up-regulated. Gene ontology (GO) enrichment analysis shows that ZEA has a major effect on the connective function, cell composition, cell cycle, and energy metabolism of the TM3 Leydig cells. Using the results of the GO and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, we select the Ras and Rap1 signaling pathways that are closely related to the occurrence of cancer. The differentially expressed genes visualized in the KEGG pathway were selected for RT-qPCR differential gene expression validation. The results show that the gene expression results are consistent with the transcriptome sequencing results. This study thus provides a theoretical molecular basis for the mechanism of ZEA carcinogenesis.