LncRNA PTCSC3 Alleviates the Postoperative Distant Recurrence of Gastric Cancer by Suppression of lncRNA HOXA11-AS.

Introduction: It is worldwide accepted that lncRNA PTCSC3 is a tumor suppressor in glioma and thyroid cancer, whereas its role in the recurrence of gastric cancer is unknown. Patients and Methods: We recruited 80 GC patients (46 males and 34 females, 44 to 68 years, 56.3 +/- 6.7 years) in our study. Two human GC cell lines AGS and SNU-1 were transfected with PTCSC3 and HOXA11-AS expression vectors. Then, qPCR was used to detect the level of relative mRNA. Both invasion and migration assays were performed to detect the effect of the lncRNA on gastric cancer cell motility. Results: In the present study, we showed that PTCSC3 was downregulated in plasma of gastric cancer patients than in plasma of healthy controls. Follow-up study indicated that PTCSC3 was further downregulated in patients with distant-recurrence but not in patients with local recurrence only or non-recurrence. LncRNAHOXA11-AS was upregulated in plasma of gastric cancer cells than in plasma of healthy controls and was inversely correlated with PTCSC3 in plasma of gastric cancer patients. PTCSC3 overexpression mediated the downregulation of HOXA11-AS in gastric cancer cells, while HOXA11-AS overexpression failed to significantly affect PTCSC3. PTCSC3 overexpression led to inhibited, while HOXA11-AS overexpression led to promoted migration and invasion of gastric cancer cells. In addition, HOXA11-AS overexpression reduced the effects of PTCSC3 overexpression. Discussion: Therefore, lncRNA PTCSC3 alleviates in the postoperative distant recurrence of gastric cancer possible by suppression of HOXA11-AS.