EPO and hepatocellular carcinoma: A total of 36 proteins encoded by the parental genes of the differentially expressed circular RNAs interacted with other parental gene products, including some muscle-related proteins, such as the fibroblast growth factor receptor 2 (FGFR2), members of the adenylate cyclase and EPH families, and erythropoietin-producing hepatoma (RBFOX1) (Figure 3C).