Hsa_circ_0001535 inhibits the proliferation and migration of ovarian cancer by sponging miR-593-3p, upregulating PTEN expression

Background: Hsa_circ_0001535 is involved in biological processes in various tumors. However, the biological effects and related mechanism of hsa_circ_0001535 in ovarian cancer (OC) is unclear. This work is aimed to probe the biological function and underlying mechanism of hsa_circ_0001535 in OC, especially sponged with mi-RNA, require further elucidation.

Methods: Hsa_circ_0001535 expression in OC tissues and cell lines were examined by qRT-PCR. Hsa_circ_0001535 overexpression model was constructed by lentivirus-mediated transfection in two OC cell lines, and the biological functions of hsa_circ_0001535 were evaluated by CCK-8, transwell assay and Western blot. Dual luciferase reporter gene assay was respectively used to explore the relationship between hsa_circ_0001535 and miR-593-3p, as well as miR-593-3p and PTEN. The expression of miR-593-3p and PTEN were detected by qRT-PCR in two OC cell lines and OC tissues.

Results: Hsa_circ_0001535 was down-regulated in OC tissues and cell lines. Hsa_circ_0001535 overexpression inhibited proliferation, migration and EMT marker expression in OC cells. Of interest, hsa_circ_0001535 targeted miR-593-3p and reduced its RNA level in OC cells. PTEN was a target gene of miR-593-3p, which was up-regulated by inhibiting miR-593-3p in OC cells. Furthermore, miR-593-3p mimic treatment reversed the up-regulation of PTEN by hsa_circ_0001535 overexpression in OC cells.

Conclusions: The above results showed that hsa_circ_0001535 acted as a molecular sponge for miR-593-3p to repress miR-593-3p expression, and promoted the expression of PTEN, thus inhibited proliferation and migration of OC cells. Our research provides a potential therapeutic target for ovarian cancer patients.