Table 2 CircRNAs with opposite functions to their host genes

circGSK3β

Up

GSK3β

Down

Esophageal squamous cell carcinoma (ESCC)

Promote ESCC cell migration, invasion and EMT

circGSK3β/GSK3β/β-catenin signaling

[80]

circPOK

Up

Zbtb7a

Down

Mesenchymal tumor

Regulate pro-proliferative and pro-angiogenic factors by co-activation of the ILF2/3 complex

circPOK/ILF2/3 complex/Il6 and Vegf

[6]

hsa_circ_0079993

Up

POLR2J4

Down

Colorectal cancer

Promote cell proliferation and tumor growth in vivo

circ_0079993/miR-203a-3p.1/CREB1

[81]

circ-HuR (hsa_circ_0049027)

Down

HuR

Up

Gastric cancer

Inhibit the growth, invasion, and metastasis

of gastric cancer cells in vitro and in vivo

circ-HUR/CCHC-type zinc finger nucleic acid binding protein (CNBP)/HuR

[82]

circ-Ccnb1

Down

Ccnb1

Up

Breast cancer

Inhibit cell proliferation, migration, invasion and tumor growth in vivo

circ-Ccnb1 bind to both Ccnb1 and Cdk1 proteins to form a large complex to dissociate the formation of Ccnb1-Cdk1 complex and inhibit the tumor-promoting function of its host gene Ccnb1

[83]

circYap

Down

Yap

Up

Breast cancer

Inhibit cell proliferation, adhesion, migration and invasion

circYap/PABP and eIF4G/Yap

[84]

circPABPN1 (hsa_circ_0031288)

Down

PABPN1

Up

Cervical carcinoma

Inhibit cell proliferation

circPABPN1/HuR/PABPN1

[85]

circ-MYBL2

Down

MYBL2

Up

Multiple myeloma (MM)

Inhibit MM cell viability, DNA synthesis, cell cycle progression and tumor growth in vivo

circ-MYBL2/Cyclin F/MYBL2

[86]

circSMARCA5

Down

SMARCA5

Up

Breast cancer

Inhibit DNA damage repair function and enhance the cisplatin response in breast cancer in vitro and in vivo

circSMARCA5 formed R-loops with its host gene to terminate SMARCA5 transcription

[87]

circ_0004296

Down

ETS1

Up

Prostate cancer

Inhibit cell proliferation, migration, invasion, epithelial-mesenchymal transition, tumor growth and metastasis in vivo

circ_0004296/EIF4A3/ETS1

[88]