Diagnostic and Prognostic Potential of Long Non-Coding RNAs GAS5, MALAT1, CCAT2, HOTAIR and H19 in Colorectal Cancer Cases with Peritoneal Metastases

Abstract It was aimed to evaluate long non-coding RNAs (lncRNAs) in terms of diagnosis and prognosis in colorectal cancer (CRC) cases with peritoneal metastasis who underwent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. Paraffinized 32 CRC tissue and 32 adjacent normal colon tissue of 32 cases, and paraffinized metastatic 10 peritoneal tumor tissue and 10 adjacent normal peritoneal tissues of 10 cases were included in. Expression levels of lncRNAs GAS5, MALAT1, CCAT2, HOTAIR and H19 were measured by qRT-PCR, clinicopathological and demographic characteristics of the patients were also recorded. 11 (34%) patients were female and 21 (66%) were male. The mean age was 54.59±11.97 (24-73 years). Expression levels of GAS5 decreased significantly in colon tumor tissues compared to normal colon tissues (p<0.001), while HOTAIR, CCAT2, MALAT1 and H19 levels were increased significantly (p<0.001). In tissues where the tumor has metastasized to the peritoneum, the expression levels of GAS5 decreased significantly compared to the adjacent normal peritoneal tissue (p=0.028), while HOTAIR, CCAT2, MALAT1 and H19 levels were increased significantly (p=0.007, p=0.005, p=0.009, p=0.028, respectively). No association was found between lncRNAs and survival. In conclusion, lncRNAs GAS5, HOTAIR, CCAT2, MALAT1 and H19 may be used as diagnostic markers in CRC cases with peritoneal metastasis.