Abstract
Long noncoding RNAs (lncRNAs) are frequently dysregulated in malignancies and serve as significant regulators of tumorigenesis. The role of the lncRNA DNAH17-AS1 in gastric cancer (GC) remains incompletely understood. In this study, we explored the biological function and underlying mechanism of DNAH17-AS1 in GC. Differences in DNAH17-AS1 expression between GC and normal tissues were evaluated via The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), and qRT-PCR validation. CCK-8, colony formation, animal, and flow cytometry assays were performed to detect the effects of DNAH17-AS1 on GC cell proliferation. Further biological experiments combined with bioinformatics analyses were performed to reveal the molecular mechanism involved. The results indicated that DNAH17-AS1 was strongly overexpressed in GC tissues and cells and that high expression of DNAH17-AS1 was correlated with lager tumour size, poor differentiation, and shorter survival. Silencing DNAH17-AS1 inhibited proliferation, induced G1 arrest and apoptosis in GC cells in vitro, and repressed tumorigenesis in vivo. Mechanistically, DNAH17-AS1 acted as a competitive endogenous RNA (ceRNA) for the tumour suppressor miR-202-3p and consequently prevented the degradation of ONECUT2. In addition, the DNAH17-AS1/miR-202-3p/ONECUT2 axis promoted the radioresistance of GC. In summary, DNAH17-AS1 plays crucial roles in GC progression and may be a novel promising target for therapy.