Low expression of LOC285194 is associated with poor prognosis in colorectal cancer

Abstract

Background: The long non-coding RNAs (lncRNAs) study has gradually become one of the hot topics in the field of RNA biology. One lncRNA which has attracted attention is LOC285194, a lncRNA demonstrated the potential tumor-suppressor role in osteosarcoma. The aim of this study was to examine the expression of LOC285194 in colorectal cancer (CRC) patients and to investigate the relationship between this lncRNA levels and existing clinicopathologic parameters and patient survival.

Methods: The expression of LOC285194 was detected by quantitative real-time polymerase chain reaction in pairs of tumorous and adjacent normal tissues of 81 colorectal cancer patients with a follow-up of 5 years, as well as in three colorectal cancer cell lines and normal intestinal mucous cell line. Then, we analyzed the potential relationship between this lncRNA levels in tumor tissues and existing clinicopathological features of CRC, and clinical outcome.

Results: The relative expression levels of LOC285194 was significantly lower in tumor tissues (p<0.001) and colorectal cancer cell lines compared with adjacent normal tissues and normal intestinal mucous cell line. In addition, low expression of LOC285194 was correlated with larger tumor size (p=0.015), higher tumor stage (p=0.034), and more distant metastasis (p=0.046). Kaplan-Meier analysis indicated that patients with low LOC285194 expression had a poor disease free survival (p=0.010). Moreover, multivariate analysis showed that decreased expression of LOC285194 was an independent predictor of disease-specific survival.

Conclusion: Our data indicate that LOC285194 might be a novel prognostic indicator in colorectal cancer and may be a potential target for diagnosis and gene therapy.

Figure 1

LOC285194 expression levels assessed by quantitative real-time PCR in cancerous tissue and adjacent normal mucosa. The LOC285194 expression levels were normalized to GAPDH. LOC285194 expression was significantly lower in cancerous tissues compared with noncancerous tissues. Data are means ± SEM (p < 0.001).

Figure 2

Expression of LOC285194 in three colon cancer cell lines and normal intestinal mucous cell line. LOC285194 expression levels were determined by quantitative real-time polymerase chain reaction in 3 colon cancer cell lines (CaCO-2, HCT8, and LoVo cells) and normal intestinal mucous cell line (CCC-HIE-2). Data are means ± SEM (n = 3). *Significantly different from control (p < 0.05).

Figure 3

Kaplan-Meier survival curves according to LOC285194 level. Patients with low LOC285194 expression (n = 48) had a significantly poorer prognosis than those with high LOC285194 expression (n = 33, p = 0.010). P-value was calculated by Log-Rank test.