Long Noncoding RNA AFAP1-AS1 Promotes Cell Proliferation and Metastasis via the miR-155-5pFGF7 Axis and Predicts Poor Prognosis in Gastric Cancer

Abstract EN

Background.

Actin filament-associated protein 1-antisense RNA 1 (AFAP1-AS1) plays an important role in the development and progression of several human cancers.

However, its biological function in gastric cancer (GC) progression is still unknown.

Methods.

We used qRT-PCR to detect the relative expression of AFAP1-AS1 in GC tissues and cell lines.

The loss-of-function assays were conducted to detect the effect of AFAP1-AS1 on GC development.

Bioinformatics analysis, luciferase reporter gene analysis, and RIP analysis were used to identify and validate target genes of AFAP1-AS1.

Finally, rescue tests were performed to confirm the influence of the AFAP1-AS1-miR-155-5p-FGF7 axis on GC development.

Results.

AFAP1-AS1 was upregulated in GC tissues and cell lines and was closely correlated with poor prognosis of GC patients.

AFAP1-AS1 knockdown inhibited proliferation, migration, and invasion of GC cells, indicating that AFAP1-AS1 acts as an oncogene in GC.

Bioinformatics analysis, dual-luciferase reporter gene detection, and RIP assays validated that AFAP1-AS1 directly interacts to miR-155-5p and could positively affect cell proliferation, migration, and invasion by regulation of the expression of miR-155-5p and FGF7.

Further rescue assays revealed that AFAP1-AS1 promotes cell proliferation and metastasis through the miR-155-5p/FGF7 axis in GC.

Conclusions.

AFAP1-AS1 might be an oncogenic lncRNA that promoted GC progression by acting as a competing endogenous RNA (ceRNA) that regulates the expression of FGF7 through sponging miR-155-5p, suggesting that AFAP1-AS1 may be a novel potential therapeutic target for GC.