Antisense Long Noncoding RNA HIF1A-AS2 Is Upregulated in Gastric Cancer and Associated with Poor Prognosis

Long noncoding RNAs (lncRNAs) have been recently shown to play important regulatory roles in fundamental biological processes, and many of them are deregulated in several human cancers. LncRNA hypoxia-inducible factor 1alpha antisense RNA-2 (HIF1A-AS2) is overexpressed in nonpapillary clear-cell renal carcinomas and involved in cancer progression.

This study was to evaluate the expression of HIF1A-AS2 in gastric cancer (GC) and further explore its biological function in GC cells.

Quantitative real-time polymerase chain reaction was used to detect the expression level of HIF1A-AS2 in GC tissues. The correlation of its expression with clinicopathological features was analyzed. Area under receiver operating characteristic curve (ROC(AUC)) was constructed to evaluate the diagnostic value of HIF1A-AS2. Besides, tumor cell proliferation was assessed following knockdown of HIF1A-AS2, by MTT and colony formation assay in vitro, and tumor formation assay in a nude mouse model in vivo.

The expression of HIF1A-AS2 was upregulated in GC tumorous tissues compared with the adjacent normal tissues (P < 0.001). Its overexpression was correlated with TNM stages (P = 0.008), tumor invasion (P = 0.016), lymph node metastasis (P = 0.042), and poor prognosis (P = 0.001). In addition, ROC(AUC) of HIF1A-AS2 was up to 0.673 (95 % CI 0.596-0.744, P < 0.001). Moreover, knockdown of HIF1A-AS2 expression by siRNA could inhibit cell proliferation in vitro and tumorigenesis in vivo.

HIF1A-AS2 is overexpressed in GC and may play a pivotal role in tumor cell proliferation. It can be used as a potential diagnostic and prognostic biomarker for GC.