Expression and significance of lnc-RNA SERTAD1-1 in colorectal cancer

Objective To evaluate the effect of the long non-coding RNA（lncRNA）-SERTAD1-1 （lnc-SERTAD1-1） on the proliferation, migration and prognosis of colorectal cancer （CRC）. Methods A total of 125 samples were collected from CRC patients. The expression levels of lnc-SERTAD1-1 in the cancer tissues and adjacent normal tissues were measured. The correlation between lnc-SERTAD1-1 and clinicopathological characteristics was analyzed. The effect of lnc-SERTAD1-1 upon clinical prognosis of CRC patients was evaluated. The expression levels of lnc-SERTAD1-1 in normal human colon tissue cell CCD-18Co and human CRC cell line HCT15 were determined. HCT15 cells （HO） containing the overexpression of the target gene lnc-SERTAD1-1 and HCT15 cells （HOC） containing an empty vector plasmid were constructed by using lentiviral transfection. The expression levels of lnc-SERTAD1-1 and SERTAD1 protein were determined. The effect of lnc-SERTAD1-1 upon the proliferation and migration ability of CRC cells was assessed. Results Compared with adjacent normal tissues, lnc-SERTAD1-1 was lowly expressed in the CRC tissues and cancer cells （cancer tissues： 0.002 198±0.000 499 vs. 0.002 998±0.000 392,P < 0.001; cancer cells： 0.000 123±0.000 010 vs. 0.000 182±0.000 012, P < 0.004）. The expression level of lnc-SERTAD1-1 was significantly correlated with the location, size and general classification of the tumor in CRC patients （all P < 0.05）. Among 125 CRC patients, high expression of lnc-SERTAD1-1 （≥0.000 970） was an independent protective factor of the overall survival （OS） and disease-free survival （DFS） of CRC patients （HR = 0.228, 95%CI：0.107-0.485, P < 0.001 for OS; HR = 0.228, 95%CI：0.103-0.506, P < 0.001 for DFS）. In vitro experiment revealed that up-regulation of lnc-SERTAD1-1 expression significantly inhibited the proliferation and migration of CRC cells （both P < 0.05）. Conclusion lnc-SERTAD1-1 plays the role of tumor suppressor in CRC via suppressing cell proliferation and migration, which is a critical prognostic factor of CRC．