Large-scale omics data reveal the cooperation of mutation-circRNA-miRNA-target gene network in liver cancer oncogenesis

Aims: Clarifying the initial trigger of the differentially expressed genes in cancers helps researchers understand the cellular system as a whole network. Materials & methods: We retrieve the transcriptome and translatome of tumor and normal tissues from ten liver cancer patients and define differentially expressed genes and tumor-specific mutations. We associate the oncogenesis with the mutations by target prediction and experimental verification. Results: Upregulated genes have tumor-specific mutations in 3 ' UTRs that abolish the binding of miRNAs. For downregulated genes, their corresponding miRNAs are mutually targeted by two circRNAs, with mutations in base-pairing regions. Transfection experiments support the oncogenic role of these mutations. Conclusions: The tumor-specific mutations serve as the initial trigger of liver cancer. The mutation-circRNA-miRNA-target gene chain is completed.