Table 2 Down-regulated circRNAs in ovarian cancer

circPLEKHM3

5 tumor tissues and 5 normal ovarian tissues from patients with benign gynaecological diseases/4-week-old female athymic BALB/c nude mice

A2780, OV90 and MDAH2274

miR-9/BRCA1/DNAJB6/KLF4/AKT1 axis

↑↑ circPLEKHM3: ↓ cell growth, migration and EMT process

Patients with low levels of circPLEKHM3 showed a worse prognosis

[79]

circPLEKHM3

35 pairs of tumor tissues and ANCTs/5-week-old female BALB/c athymic mice

SKOV3, A2780 and 293T cells

miR-320a/SMG1 axis

Curcumin treatment: ↑ circPLEKHM3 levels: ↓ cell proliferation and ↑ apoptosis

[80]

circ_100395

60 pairs of tumor tissues and ANCTs

A2780, OV2008, SKOV3, IGROV1 and ES-2

miR-1228

↑↑ circ_100395: ↓ tumor growth, metastasis and EMT process

[90]

circ_0078607

20 pairs of tumor tissues and ANCTs

SKOV3 and A2780

miR-518a-5p/Fas axis

↑↑ circ_0078607: ↓ proliferation and ↑ apoptosis via sponging miR-518a-5p

[81]

circ_0078607

43 pairs of tumor tissues and ANCTs/female BALB/c nude mice

HEY, ES-2 and IOSE80

miR-32-5p/SIK1 axis

↑↑ circ_0078607: ↓ proliferation, migration, invasion, and ↑ apoptosis via sponging miR-32-5p

[82]

circ_0078607

49 pairs of tumor tissues and ANCTs

–

–

Patients with low levels of circ_0078607 had advanced FIGO stage, higher serum CA125 level, shorter PFS and OS

[83]

circATRNL1

56 pairs of tumor tissues and ANCTs/6-week-old nude mice

A2780, SKOV3, CAOV‐3, SNU119 and IOSE80

miR-378/Smad4 axis

↑↑ circATRNL1: ↓ proliferation, invasion, migration, angiogenesis and ↑ apoptosis

[91]

circHIPK3

21 high grade EOC and 21 normal ovarian tissues

A2780, SKOV3 and IOSE80

–

∆ circHIPK3: ↑ proliferation, migration, and invasion and ↓ apoptosis

[92]

circRHOBTB3

–

ovarian cancer cells

PI3K/AKT signaling pathway

↑↑ circRHOBTB3: ↓ cell proliferation, metastasis and glycolysis via inactivating PI3K/AKT signaling pathway

[93]

circEXOC6B

60 ovarian cancer patients and 60 healthy controls/BALB/c mic

A2780, SKOV3 and IOSE-80

miR-376c-3p/FOXO3 axis

↑↑ circEXOC6B: ↓ proliferation, motility and chemoresistance of ovarian cancer cells to PTX via sponging miR-376c-3p

Low levels of circEXOC6B were correlated with malignant pathological characteristics in ovarian cancer patients

[84]

circEXOC6B

–

A2870, SKOV3, OVCAR3 and IOSE80

miR-421/RUS1 axis

↑↑ circEXOC6B: ↓ proliferation, invasion and ↑ apoptosis via sponging miR-421

[85]

circ9119

40 ovarian cancer patients and 10 normal controls/5-week old female BALB/c nude mice

SKOV-3, HO-8910, A2780, ES-2, CAOV3, and OVCAR3 and FTE187

miR-21 and PTEN/Akt pathway

↑↑ circ9119: ↓ proliferation, viability and ↑ apoptosis

[86]

CDR1as

65 ovarian cancer patients and 37 normal controls

HO8910 and A2780

miR-135b-5p/HIF1AN axis

↑↑ CDR1as: ↓ proliferation, invasion and migration

[87]

Cdr1as

66 pairs of tumor tissues and ANCTs/4-week-old BALB/c female athymic mice

A2780, SKOV-3 and IOSE-80

miR-1270/SCAI axis

↑↑ CDR1as: ↓ proliferation and ↑ cisplatin-induced cell apoptosis in ovarian cancer cells via sponging miR-1270

[88]

circRNA1656

60 HGSOC tissues and 60 benign ovarian tissues

SKOV-3, HO 8910, A2780 and OVCAR-3

–

Downregulation of circRNA1656 was correlated with the FIGO stage of HGSOC

[94]

circ-ITCH

45 pairs of tumor tissues and ANCTs/5-week-old BALB/c nude mice

A2780, OVCAR3 and ISOE80

miR-106a/CDH1 axis

↑↑ circ-ITCH: ↓ proliferation, invasion, glycolysis and ↑ apoptosis via sponging miR-106a

Levels of circ-ITCH were positively associated with 5-year OS of patients

[78]

circ-ITCH

75 pairs of tumor tissues and ANCTs

UWB1.289 and UWB1.289 + BRCA1

lncRNA HULC

↑↑ circ-ITCH: ↓ proliferation via downregulating HULC

[77]

circ-ITCH

–

SKOV3, A-2780, OVCAR-3, HO-8910 and IOSE80

miR-10a

↑↑ circ-ITCH: ↓ proliferation and ↑ apoptosis via sponging miR-10a

[95]

circ-ITCH

20 pairs of tumor tissues and ANCTs/6-weeks-old female BALB/c nude mice

SK-OV-3 and Caov-3

miR-145/RASA1 axis

↑↑ circ-ITCH: ↓ viability and motility by CCK8, cell cycle, wound healing assay and invasion via sponging miR-145

[96]

circ-ITCH

77 pairs of tumor tissues and ANCTs

SKOV3 and OVCAR-3

–

High levels of circ-ITCH were associated with small tumor size, decreased FIGO stage and prolonged OS

↑↑ circ-ITCH: ↓ proliferation and ↑ apoptosis

[97]

circBNC2

83 EOC patients, 83 benign ovarian cysts, and 83 healthy controls

–

–

CircBNC2 was found to be downregulated in EOC and could be promising novel biomarker for EOC

[89]

circMTO1

48 pairs of tumor tissues and ANCTs

SKOV3 and OVCAR3 and IOSE80

miR-182-5p/KLF15 axis

↑↑ circMTO1: ↓ proliferation and invasion

[98]

circ_0007444

87 pairs of tumor tissues and ANCTs/5-week-old female nude mice

SKOV3, OV420, A2780, CAOV3, OVCAR3 and HOSEpiC

miR-570-3p/PTEN axis

↑↑ circ_0007444: ↓ proliferation, migration, and invasion, and ↑ apoptosis via sponging miR-570-3p

Low levels of circ_0007444 were correlated with advanced tumor stage and grade, large tumor size, and low 60-month percent survival

[99]

circLARP4

78 pairs of tumor tissues and ANCTs

–

–

Low levels of circLARP4 were correlated with FIGO stage, lymph node metastases and poor prognosis of OC patients

[100]

circLARP4

–

SKOV3, A2780, SW626, OVCAR3, OVCAR4 and HOSEpiC

miR-513b-5p/LARP4 axis

↑↑ circLARP4: ↑proliferation, invasion and migration

[101]

hsa_circ_0007874

4-week-old BALB/c nude mice

IGROV1, A2780, ES‐2, OV2008, and SKOV3 and ISOE80

miR-760/SOCS3 axis

↑↑ hsa_circ_0007874: ↓ proliferation and migration

[102]

circN4BP2L2

126 EOC patients, 126 benign ovarian cyst, and 126 healthy controls

SKOV3, OVCAR3, CAOV3, HO8910, TOV-112D, and IOSE80

–

↑↑ circN4BP2L2: ↓ migration and invasion

Low levels of circN4BP2L2 were correlated with advanced tumor stage, worse histological grade, lymph node metastasis and distant metastasis in EOC

[103]