Parvaneh NIKPOUR, Modjtaba EMADI-BAYGI, Sara GHASEMI

Down-regulation of circular RNA ITCH and circHIPK3 in gastric cancer tissues

Background/aim: Gastric cancer (GC) is one of the major causes of cancer mortality worldwide. As a novel type of endogenousnoncoding RNAs, circular RNAs (circRNAs) are formed by a covalent link between 5’ and 3’ ends. They are very stable and abundantin eukaryotes. As there were no reported studies on the expression profiles of circular RNA ITCH (cir-ITCH) and circHIPK3 in GC, inthe current study, we aimed to delineate the expression profiles and clinicopathological relevance of these two circRNAs in GC tissuescompared to their paired adjacent noncancerous tissues.Materials and methods: Quantitative real-time polymerase chain reaction was performed to evaluate cir_ITCH and circHIPK3expression in 30 paired gastric cancer tissues. The clinicopathological relevance of these two circular RNAs’ expression levels withgastric cancer was further examined.Results: Our results showed that the expression of cir_ITCH and circHIPK3 were significantly downregulated in GC tumoral tissuescompared with their paired adjacent nonneoplastic counterparts. Further analyses showed that cir_ITCH and circHIPK3 expressionlevels were related with numerous clinicopathological features of tumoral tissues.Conclusion: Cir_ITCH and circHIPK3 may have imperative roles in GC and serve in the future as potential prognostic biomarkers in GC.

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