MiR-1299 functions as a tumor suppressor to inhibit the proliferation and metastasis of gastric cancer by targeting ARF6.

Background: MiRNAs belong to non-coding RNAs that are involved in cancer development. Acting as a mediator, they could regulate the expression level of numerous gens. However, the expression and function of miR-1299 in gastric cancer (GC) are not clear.

Objective: To explore the role of miR-1299 in the process of GC.

Methods: We detected the levels of miR-1299 in clinical samples of GC and investigated the role of miR-1299 in the regulation of the GC cells proliferation, apoptosis and metastasis. Luciferase reporter assay was employed to verify the target of miR-1299. Additionally, the proliferation, apoptosis and metastasis of AGS and SGC7901 cells were analyzed after the overexpression of miR-1299.

Results: Our study showed the expression of miR-1299 was decreased in GC tissues and cell lines. It indicated that the cell proliferation, migration and invasion was inhibited, while the cell apoptosis was promoted by the over-expressed miR-1299. Also, we found that miR-1299 could directly target the 3'-untranslated region (3'UTR) of ARF6 genes. In addition, rescue assay demonstrated that miR-1299 overexpression promoted the cell apoptosis and inhibited cell growth, which could be attenuated by the overexpression of ARF6.

Conclusions: These findings indicate that miR-1299 regulates cell progression in GC by targeting ARF6 genes, and suggest that miR-1299 may be a tumor suppressor in the GC progression.