Abstract: Objective To detect the expression of long non-coding RNA maternally expressed gene 3 (LncRNA-MEG3) in serum of patients with primary liver cancer, and to explore the correlation between the expression level and the prognosis of patients with primary liver cancer. Methods From April 2015 to November 2016, 68 patients with primary liver cancer in our hospital were selected as the primary liver cancer group, and 70 healthy people who had routine physical examination in our hospital were selected as the control group. The expression level of serum LncRNA-MEG3 was detected by quantitative real-time polymerase chain reaction. The relationship between the serum expression level of LncRNA-MEG3 and the clinicopathological characteristics of primary liver cancer was analyzed. The influence of serum LncRNA-MEG3 expression level on the prognosis of patients with primary liver cancer was evaluated by Kaplan-Meier curve. The prognostic factors of patients with primary liver cancer were analyzed by Cox regression analysis. Results The serum expression level of LncRNA-MEG3 in the primary liver cancer group was significantly lower than that in the control group (P<0.05). The serum expression of LncRNA-MEG3 in patients with primary liver cancer had close relationship with clinical stage, differentiation degree and cirrhosis (P<0.05), but no relationship with gender, age or tumor diameter (P>0.05). The 3-year survival rate in the low expression group of serum LncRNA-MEG3 was significantly lower than that in the high expression group (P<0.05). Cox regression analysis showed that low expression of LncRNA-MEG3 and clinical stage were independent risk factors for the prognosis of patients with primary liver cancer (HR=2.500, 95% CI: 1.624-3.849; HR=2.024, 95% CI: 1.307-3.135). Conclusion The serum expression level of LncRNA-MEG3 is significantly decreased in patients with primary liver cancer, and it is closely related to the clinical stage, differentiation degree, liver cirrhosis and prognosis of patients. It suggests that LncRNA-MEG3 may be a potential index for the disease assessment and the prognosis prediction of primary liver cancer.

Key words: Primary liver cancer, Long non-coding RNA maternally expressed gene 3, Clinicopathological characteristics, Prognosis