Upregulation of long noncoding RNA ZFAS1 predicts poor prognosis and prompts invasion and metastasis in colorectal cancer

Purpose: ZFAS1 is a newly identified long non-coding RNA. The present study investigated the relationships of ZFAS1 expression with clinicalpathologic parameters and the prognosis of patients with colorectal cancer (CRC). The effects of ZFAS1 on cell migration, invasion and metastasis were also been evaluated in CRC cell lines. Methods: A total of 159 paired primary CRC tissues and adjacent noncancerous tissues (NCTs) were collected and were tested for the expression of ZFAS1. Cell migration and invasion were measured by wound-healing and Transwell assays, respectively. Tumor metastasis was assessed using a lung metastasis model of nude mouse. Results: The ZFAS1 expression was significantly upregulated in 47.8% (76 of 159) of cancerous tissues compared with NCTs(p < 0.0001), and was higher in metastatic tumors than in corresponding primary CRC tumors (p = 0.010). ZFAS1 expression in CRC was positively correlated with lymphatic invasion (p = 0.045) and TNM stage (p = 0.003). Patients with increased ZFAS1 expression showed shorter relapse-free survival and overall survival (p < 0.05). Cox multivariate analyses confirmed that ZFAS1 expression is an independent prognostic factor in CRC (p < 0.05). The knockdown of ZFAS1 decreased cell migration and invasive ability of LoVo and HCT116 cells in vitro (p < 0.05). Moreover, silencing ZFAS1 expression inhibited the in vivo metastasis of CRC cells (p < 0.05). Conclusions: The expression of ZFAS1 is positively correlated with TNM stage and appears to be a new prognostic factor in CRC. ZFAS1 promptes cell migration, invasive and metastasis ability of CRC cells. (C) 2016 Elsevier GmbH. All rights reserved.