NRAS and hepatocellular carcinoma: Mechanistically, we identified that circ_0063513 can induce HCC development by regulating miR-27b-3p/NRAS/ERK axis in combination with bioinformatics analyses and in vitro and in vivo, and immune infiltration-related analyses revealed that circRanGAP1 can also affect the infiltration level of tumor-associated macrophages.