Table 2.

Functions of circRNA–protein interactions. ↑ represents upregulation and ↓ represents inhibition.

circRNA	Cell/Tissue, Localization	Cellular Localization	Interacting Proteins	Activity	Ref(s).
CircZKSCAN1	HCC	Cytoplasm	FMRP	Cancer cell stemness↑	[51]
CircSMARCA5	Glioblastoma	-	SRSF1	Angiogenesis and cell migration↓	[52,53]
CircE2F2	Ovarian cancer	Cytoplasm	HuR	Cell migration↑	[54]
CircFECR1	Breast cancer tissue	Nucleus and cytoplasm	TET1 demethylase	Metastasis↑	[55]
CircNSUN2	Colorectal cancer	Cytoplasm	YTHDC1	Metastasis↑	[56]
CircANRIL	Atherosclerosis	-	PES1	Apoptosis↑	[57]
CircAmotl1	Heart	-	AKT1	Apoptosis↓	[58]
CircDNMT1	Breast cancer	Nucleus	AUF1	Apoptosis↓	[59]
CircDONSON	Gastric cancer	-	NURF complex	Apoptosis↓	[60]
CircRHOT1	HCC	Nucleus	TIP60	Apoptosis↓	[61]
CircE2F3	Retinoblastoma	Cytoplasm	HNRNPK	Apoptosis↓	[62]
CircFoxo3	Breast cancer	Cytoplasm	p53, MDM2	Apoptosis↑	[63]
CircFoxo3	Cardia fibroblast	Cytoplasm	p21, CDK2	Cell proliferation↓	[44]
CircFoxo3	Heart	Cytoplasm	ID1, E2F1, HIF1α, FAK	Replicative senescence↑	[64]
CircBACH1	HCC	Nucleus and cytoplasm	HuR	Cell proliferation↑	[65]
CircCcnb1	Breast cancer	Nucleus	H2AX	Cell proliferation↑	[66,67]
CircMTO1	Breast cancer	Cytoplasm	TRAF4	Cell proliferation↓	[68]
CircPCNX	HeLa	Cytoplasm	AUF1	Cell proliferation↓	[69]
CircCUX1	Neuroblastoma	-	EWSR1	Cell proliferation↑	[70]
CircACC1	Colorectal cancer	Cytoplasm	AMPK	Glycolysis and fatty acid oxidation↑	[71]
Ci-Ins2	Pancreatic β-cells	Nucleus	TARDBP	Insulin secretion↑	[72]
CircPABPN1	HeLa	-	HuR	PABPN1 translation↓	[43]
CircAGO2	Gastric cancer	Cytoplasm	HuR	Binding of RISC to mRNAs↓	[73]
CircHECTD1	Alveolar macrophage	Cytoplasm	ZC3HI2A	Macrophage differentiation↑	[74]
CircSamd4	C2C12 myoblast	Cytoplasm	PUR proteins	Myogenesis↑	[75]
CircYap	Cardiac fibrosis	Nucleus	TPM4 and ACTG	Actin polymerization↓	[76]
CircARSP91	HCC	-	ULBP1	Cell death by NK cells↑	[77,78]
Circ0005276	Prostate cancer	-	FUS	Autophagy↓	[79]