Long non-coding RNAs (lncRNAs) are key mediators of
cancer. The dysregulation of a
lncRNA, CASC15, has been linked to several
cancers, except
lung cancer. Here, the aim of the study was to explore the role and mechanism of CASC15 in
lung cancer regulation, with the focus on its interaction with a potential target, microRNA-766-5p (miR-766-5p) and an oncogene,
kallikrein-related
peptidase 12 (KLK12). Quantitative real-time PCR (qRT-PCR) was used to assess levels of CASC15, miR-766-5p and KLK12 in
lung cancer tissues or cells. Western blot analysis was used to detect KLK12
protein expression. Ectopic expression of CASC15 was induced by a lentiviral system.
CCK-8 and transwell assays were used to evaluate
lung cancer cell proliferation and invasion, respectively. The interaction among CASC15, miR-766-5p and KLK12 was investigated by bioinformatical analysis and
luciferase assay. In
lung cancer tissue and cells, CASC15 was upregulated, while miR-766-5p was downregulated. Overexpression of CASC15 promoted
lung cancer cell proliferation and invasion. A negative correlation was found between CASC15 and miR-766-5p levels. Overexpression of miR-766-6p reversed the
cancer-promoting role of CASC15 in
lung cancer cells, which was mediated by KLK12. The
tumor-promoting role of CASC15 and
tumor-suppressing role of miR-766-5p were also validated in vivo in
tumor bearing mice, and KLK12 was also shown as an important mediator. CASC15 promotes
lung cancer through the miR-766-5p/KLK12 axis, indicating that CASC15 is a potential therapeutic in
lung cancer.