Background: Circ-ZNF609 has been shown to modulate cancer progression in several kinds of cancer. However, the role of circ-ZNF609 played in lung adenocarcinoma (LAUD) remains unclear. In this study, we investigated the role of circ-ZNF609 in regulating LAUD cancer progression.

Materials and methods: Quantitative reverse transcription polymerase chain reaction was conducted to evaluate circ-ZNF609 expression in 52 LAUD tissues and 52 matched adjacent normal tissues, LAUD cell lines and bronchial epithelial cell line (HBE). The direct interaction between miR-1224-3p and circ-ZNF609 or EVT1 was verified using luciferase reporter assay and RNA immunoprecipitation assay. Cell Counting Kit-8, colony formation assay, cell-cycle analysis were utilized to examine the effect of circ-ZNF609 or miR-1224-3p on cell proliferation.

Results: Circ-ZNF609 was significantly upregulated in LAUD tissues and cell lines, and its inhibition induced reduced cell proliferation of LAUD cells. Mechanistically, we demonstrated that circ-ZNF609 sponged miR-1224-3p to promote EVT1 expression. More importantly, miR-1224-3p overexpression strongly suppressed circZNF609-induced malignant phenotype of LAUD cells.

Conclusion: Circ-ZNF609 enhances LAUD progression by increasing oncogenic EVT1 expression via sponging miR-1224-3p, revealing that circ-ZNF609/miR-1224-3p/ETV1 axis may be a promising therapeutic target for LAUD treatment.