TABLE 1.
Verified circRNAs involved in various ocular diseases.
| Ocular diseases | circRNAs | Expression | Functions | Related networks | References |
| DR | circ_0005015 | Upregulated in the plasma, vitreous samples, and FVMs of DR patients. | Promote the angiogenic function of HRVECs in vitro. | miR-519d-3p-MMP-2/STAT3/XIAP | Zhang S.-J. et al., 2017 |
| circHIPK3 | Upregulated in HRVECs under HG conditions, DR models, the plasma, vitreous samples, and FVMs of DR patients. | Promote the angiogenic function of HRVECs under HG conditions in vitro. Aggravate the DM-induced retinal vascular dysfunction in vivo. | c-myb, miR-30a-3p/VEGFC/FZD4/WNT2 | Shan et al., 2017 | |
| circZNF609 | Upregulated in HUVECs under HG conditions, DR models, the plasma, and FVMs of DR patients. | Promote the angiogenic function of HUVECs under HG conditions in vitro. Aggravate the DM-induced retinal vascular dysfunction in vivo. | miR-615-5p-MEF2A | Liu C. et al., 2017 | |
| circDMNT3B | Downregulated in HRMECs under HG conditions and the FVMs of DR patients. | Suppress the angiogenic function of HRMECs under HG conditions in vitro. Ameliorate DM-induced retinal vascular dysfunction and visual damage in vivo. | miR-20b-5p-BAMBI | Zhu et al., 2019 | |
| circPWWP2A | Upregulated in retinal pericytes under DM related stresses instead of HRVECs, DR models, and the FVMs of DR patients. | Promote the viability, proliferation, antiapoptosis, recruitment toward HRVECs of pericytes under DM-related stresses in vitro but affect HRVECs indirectly via exosomes. Ameliorate DM-induced retinal vascular dysfunction and pericyte dysfunction in vivo. | miR-579-angiopoietin1/occludin/SIRT1 | Liu et al., 2019 | |
| circZNF532 | Upregulated in retinal pericytes following DM-related stresses, DR models, and the vitreous samples of DR patients. | Promote the viability, proliferation, antiapoptosis, recruitment toward HRVECs of pericytes under DM-related stresses in vitro. Ameliorate DM-induced retinal vascular dysfunction and pericyte dysfunction in vivo. | SP1, miR-29a-3p-CSPG4/LOXL2/CDK2 | Jiang et al., 2020 | |
| ROP | circZNF609 | Upregulated at the neovascularization stage of OIR models. | Aggravate the oxygen-induced retinal vascular dysfunction in vivo. | miR-615-5p-MEF2A | Liu C. et al., 2017 |
| Exudative AMD | circZBTB44 | Upregulated in chorioretinal ECs under hypoxic conditions, CNV models, the aqueous humor of nAMD patients. | Promote the angiogenic function of chorioretinal vascular ECs under hypoxic conditions in vitro. Aggravate the CNV development in vivo. | miR-578-VEGFA/VCAM1 | Zhou et al., 2020 |
| Atrophic AMD | circNR3C1 | Downregulated in RPE cells under oxidative stress and the blood serum of AMD patients. | Maintain the RPE phenotypes and functions in vitro and in vivo to prevent AMD progression. | miR-382-5p-PTEN-AKT/mTOR | Chen X. et al., 2020 |
| Glaucoma | circZRANB1 | Upregulated in glaucoma model and the aqueous humor of glaucoma patients. | Promote the viability, proliferation, and activation of Müller cells directly, but indirectly inhibit RGC function in vitro. Promote the retinal reactive gliosis and glia cell activation (glaucomatous retinal neuropathy) in vivo. | miR-217-RUNX2 | Wang et al., 2018b |
| circZNF609 | Upregulated in glaucoma model and the aqueous humor of glaucoma patients. | Promote the viability, proliferation, and activation of Müller cells directly, but indirectly inhibit RGC function in vitro. Promote the retinal reactive gliosis and glia cell activation (glaucomatous retinal neuropathy), but inhibit RGC survival in vivo. | miR-615-METRN | Wang et al., 2018a | |
| ARC | circHIPK3 | Downregulated in lens capsules of patients with various types of ARC. | Promote the viability, proliferation, EMT and antiapoptosis upon oxidative stress of HLECs in vitro. | miR-193a-3p-CRYAA | Liu et al., 2018, 3 |
| Corneal neovascularization | circZNF609 | Upregulated in the corneal epithelium of corneal neovascularization models. | Promote the angiogenic function of HCEKs in vivo. Aggravate the corneal angiogenesis in vivo. | miR-184-AKT/β-catenin/VEGF | Wu et al., 2020 |
| circKIFAP3 | Downregulated in alkali burn-induced neovascularization corneal models and patients’ vascularized corneas. | Suppress the angiogenic function of HUVECs in vitro. | Zhou Y.-F. et al., 2019 | ||
| Pterygium | circ_0085020 | Upregulated in pterygium tissues | Promote the viability, proliferation, migration, and antiapoptosis under UV exposure of pterygium fibroblasts and epithelial cells in vitro. | Li X.-M. et al., 2018 | |
| PVR | circ_0043144 | Upregulated in serum ERMs of PVR patient. | Promote the proliferation, migration, and secretion ability of RPE cells in vitro. | Yao et al., 2019 | |
| Retinoblastoma | circ_0001649 | Downregulated in RB cell lines and RB tissues of patients. | Suppress the proliferation and antiapoptosis of RB cells in vitro. Suppress the xenograft tumor growth of RB in vivo. | AKT/mTOR | Xing et al., 2018 |
| circ−0075804 | Upregulated in RB cell lines and RB tissues of patients. | Promote the proliferation and antiapoptosis of RB cells in vitro. Promote the xenograft tumor growth of RB in vivo. | E2F3, HNRNPK | Zhao et al., 2020 | |
| Conjunctival melanoma | circMTUS1 | Upregulated in CM tissues. | Promote the proliferation of CM cell lines in vitro. Promote the xenograft tumor growth of CM in vivo. | Shang et al., 2019 |
DR, Diabetic retinopathy; FVM, fibrovascular membrane; HRVECs, human retinal vascular ECs; MMP-2, matrix metallopeptidase 2; STAT3, signal transducer and activator of transcription 3; XIAP, x-linked inhibitor Of apoptosis; HIPK3, homeodomain interacting protein kinase 3; HG, high glucose; DM, diabetes mellitus; VEGF, vascular endothelial growth factor; FZD4, frizzled-4; WNT2, Wnt family member 2; ZNF, zinc finger protein; HUVECs, human umbilical vein endothelial cells; MEF2A, myocyte-specific enhancer factor 2A; DMNT3B, DNA (cytosine-5-)-methyltransferase 3 beta; ECs, endothelial cells; HRMECs, human retinal microvascular ECs; BAMBI, BMP and activin membrane bound inhibitor; PWWP2A, PWWP domain containing 2A; SIRT1, sirtuin 1; SP1, specificity protein 1; CSPG4, chondroitin sulfate proteoglycan 4; LOXL2, lysyl oxidase homolog 2; CDK2, cyclin-dependent kinase 2; ROP, Retinopathy of prematurity; OIR, oxygen?induced retinopathy; AMD, Age-related macular degeneration; ZBTB44, zinc finger and BTB domain containing 44; VCAM1, vascular cell adhesion protein 1; nAMD, neovascular AMD; CNV, choroidal neovascularization; NR3C1, nuclear receptor subfamily 3 group C member 1; RPE, retinal pigment epithelium; PTEN, phosphatase and tensin homolog on chromosome ten; mTOR, mammalian target of rapamycin; ZRANB1, zinc finger RAN-binding domain containing 1; RGCs, retinal ganglion cells; RUNX2, runt-related transcription factor 2; METRN, meteorin; ARC, age-related cataracts; EMT, epithelial-mesenchymal transition; HLECs, human lens epithelial cells; CRYAA, crystallin alpha A; HCEKs, corneal epithelial keratinocytes; KIFAP3, kinesin-associated protein 3; UV, ultraviolet radiation; PVR, proliferative vitreoretinopathy; ERMs, epiretinal membranes; RB, retinoblastoma; E2F3, E2F transcription factor 3; HNRNPK, heterogeneous nuclear ribonucleoprotein K; MTUS1, microtubule-associated scaffold protein 1; CM, conjunctival melanoma.