Fig. 4From: Current prevalence status of gastric cancer and recent studies on the roles of circular RNAs and methods used to investigate circular RNAsThe three forms of covalently joined circRNAs in cells: exon-exon, exon-intron (intronic), and intron-intron (intronic-intronic). circRNAs may serve as miRNA sponges to prevent binding to target genesBack to article page