LIN28 expression and prognostic value in hepatocellular carcinoma patients who meet the Milan criteria and undergo hepatectomy

Stem cell marker LIN28, related closely with SOX2 and OCT4, has been studied as a biomarker for the maintainance of pluripotent cells in several malignancies. Our previous study showed that SOX2 and OCT4 were negative predictors for hepatocellular carcinoma (HCC). However, the predictive value of LIN28 in HCC outcome is still undetermined. We hypothesized that LIN28 may also play a role as a biomarker for HCC. To test this hypothesis, we examined the expression of LIN28 in 129 radically resected HCC tissues using reverse transcription-polymerase chain reaction and analyzed the association of LIN28 expression with clinicopathologic features and prognosis. Our study showed that LIN28 was expressed at a higher frequency in tumor tissues than in non-HCC tissues (45.0% vs. 21.7%, P = 0.020). Moreover, LIN28 expression was significantly increased in cases with large tumor size (P = 0.010). Univariate analysis did not reveal a significant correlation between LIN28 expression and overall survival or recurrence-free survival. For HCC patients who met the Milan criteria, stratified analysis revealed shorter overall survival (P = 0.007) and recurrence-free survival (P < 0.001) in those with detectable LIN28 expression compared to those with no detectable LIN28 expression. Furthermore, multivariate analysis revealed that LIN28 was a negative independent predictor for both overall survival (hazard ratio= 7.093, P = 0.017) and recurrence-free survival (hazard ratio=5.518, P = 0.004) in patients who met the Milan criteria. Taken together, our results suggest that LIN28 identifies low-risk and high-risk subsets of HCC patients meeting the Milan criteria who undergo hepatectomy.