Figures & data
Table 1 Relationship Between hsa_circ_0007444 Expression and Clinical Features of OC Patients
Figure 1 Low expression of circ_0007444 in OC patients predicted with poor prognosis. (A) qRT-PCR revealed the down-regulated circ_0007444 expression in OC tumor tissues compared to that in adjacent normal tissues. (B) OC cases with low circ_0007444 expression exhibited an advanced tumor stage. (C) OC patients with low circ_0007444 expression presented lower 60-month percent survival. (D) Circ_0007444 expression was not obviously changed by treatment of RNase R, indicating the stable circular structure of circ_0007444. (E) qRT-PCR indicated that circ_0007444 was down-regulated in OC cells. *P<0.05, **P<0.01.
Figure 2 Circ_0007444 inhibited proliferation, migration, invasion, and promoted apoptosis of OC cells. (A) qRT-PCR revealed that the expression of circ_0007444 in SKOV3 and OVCAR3 cells was successfully regulated by transfection. (B) According to CCK-8 assay, it could be noted that circ_0007444 prominently attenuated proliferation of OC cells. (C) Flow cytometry results indicated that circ_0007444 markedly enhanced OC cells apoptosis. (D) By wound healing assay, circ_0007444 obviously inhibited OC cells migration. (E) Transwell experiment illustrated that circ_0007444 remarkably suppressed the invasion ability of OC cells. Cells were stained by 0.1% crystal violet for 10 minutes. **P<0.01.
Figure 3 Circ_0007444 acted as a sponge for miR-570-3p. (A) Circ_0007444-WT and circ_0007444-Mut fragments containing the binding sites for miR-570-3p was designed and synthesized. (B) Luciferase reporter gene assay indicated that miR-570-3p was a target gene of circ_0007444. (C) RIP experiments revealed that circ_0007444 expression was elevated by miR-570-3p overexpression. (D) qRT-PCR circ_0007444 inhibited the expression of miR-570-3p in OC cells. (E) By qRT-PCR, miR-570-3p expression was up-regulated in tumor tissues of OC patients than that in adjacent normal tissues. (F) miR-570-3p expression was negatively correlated with circ_0007444 expression in tumor tissues of OC patients. **P<0.01.
Figure 4 PTEN expression was regulated by miR-570-3p and circ_0007444. (A) The fragments of PTEN-WT and PTEN-Mut were designed and synthesized. (B) Luciferase reporter gene assay indicated that PTEN was a target gene of miR-570-3p. (C) qRT-PCR exhibited that miR-570-3p inhibited PTEN expression and circ_0007444 promoted PTEN expression in OC cells. (D) In OC patients, PTEN expression was prominently decreased in tumor tissues than that in adjacent normal tissues. (E) Pearson’s correlation analysis revealed a positive correlation between PTEN and circ_0007444 expression in tumor tissues of OC patients. (F) A negative correlation between PTEN and miR-570-3p expression was found in tumor tissues of OC patients according to Pearson’s correlation analysis. **P<0.01.
Figure 5 Circ_0007444 inhibited OC cells malignant phenotype by mediating the miR-570-3p/PTEN axis. (A) Expression of circ_0007444, miR-570-3p, and PTEN was successfully regulated by transfection. **P<0.01 when relative to the oe-NC group. (B) Circ_0007444 inhibited OC cells proliferation via mediating the miR-570-3p/PTEN axis. (C) Circ_0007444 enhanced OC cells apoptosis through mediating the miR-570-3p/PTEN axis. (D) Circ_0007444 suppressed OC cells migration by mediating the miR-570-3p/PTEN axis. (E) Circ_0007444 attenuated OC cells invasion via mediating the miR-570-3p/PTEN axis. Cells were stained by 0.1% crystal violet for 10 minutes. **P<0.01.
Figure 6 Circ_0007444 inhibited OC growth in vivo. (A) Circ_0007444 decreased the xenograft tumor volume in nude mice. (B) The xenograft tumors in each mice were photographed. (C) Circ_0007444 diminished the xenograft tumor weight in nude mice. (D) According to immunohistochemistry, circ_0007444 decreased Ki67 expression and increased PTEN expression in xenograft tumors. Meanwhile, circ_0007444 facilitated the apoptosis in xenograft tumors based on the Tunel assay. **P<0.01.
