Long non-coding RNA (lncRNA) TP73 antisense RNA 1 (TP73-AS1) has been characterized as an oncogenic lncRNA in GC. However, by analyzing The Cancer Genome Atlas (TCGA) dataset we observed the downregulation of TP73-AS1 in GC. In addition, TP73-AS1 is predicted to interact with microRNA-223-5p (miR-223-5p), which is also a critical player in cancer biology. This study was therefore carried out to investigate the roles of miR-223-5p and TP73-AS1 in gastric cancer (GC) and to explore the interactions between them. In this study, 68 GC patients were included as research subjects. Expression of miR-223-5p and TP73-AS1 was analyzed by RT-qPCR. Dual-luciferase assay and overexpression experiments were used to analyze gene interactions. Transwell assays were used to analyze cell invasion and migration. We found that miR-223-5p was upregulated and TP73-AS1 was downregulated in GC and they were inversely correlated. Altered miR-223-5p and TP73-AS1 expression predicted poor disease-specific survival. Dual-luciferase assay showed that miR-223-5p may bind TP73-AS1 and overexpression experiments showed that miR-223-5p overexpression downregulated TP73-AS1 in gastric cancer cells. Cell invasion and migration assays showed that miR-223-5p could promote the invasion and migration of gastric cancer cells, while TP73-AS1 could inhibit the invasion and migration of gastric cancer cells. In addition, miR-223-5p attenuated the effects of TP73-AS1 overexpression. Therefore, miR-223-5p may target TP73-AS1 to promote the invasion and migration of gastric cancer patients.
Keywords: Gastric cancer; Survival; TP73-AS1; miR-223-5p.