Expression And Clinical Significance Of AKR1B10 In Hepatocellular Carcinoma

Background and Objective Hepatocellular carcinoma (HCC) is one of the most common malignancies in China. Patients with HCC have poor prognosis and high incidence of tumor recurrence. Therefore, searching the marker for predicting early tumor recurrence is significant for improving the survival of patients with HCC. In our previous study, we found aldo-keto reductase family 1 member B10 (AKR1B10) is up-regulated in HCC by iTRAQ and 2DLC-MS/MS proteomics analyses. This study aimed to examin the expression of AKR1B10 in HCC, analyze the relationship between the expression of AKR1B10 and the exporsure of aflatoxin B1 (AFB1), and evaluate the impact of AKR1B10 in predicting early tumor recurrence of patients with HCC after liver resection.Methods 1. Between January 2013 to June 2014, a total of 124 patients were enrolled in this study and their HCC tissues, adjacent non-tumor tissues and tissue slices were collected. Normal liver tissues and tissue slices of eight patients with hepatic hemangioma were also collected. The expression of AKR1B10 mRNA was determined by quantitative real-time PCR and the expression of AKR1B10 protein was determined by immunohistochemistry and Western blot analysis.2. Gene sequencing was performed to examine the mutation in codon 249 of the p53 gene of HCC tissues and determine the AFB1 related HCC. Expression levels of AKR1B10 mRNA in HCC and adjacent non-tumor tissues were compared between patients with AFB1 related HCC and non-AFB1 related HCC.3. Relationships between the expression of AKR1B10 mRNA of tumor and clinicopathologic characteristics of patients with HCC were analyzed. The impact of AKR1B10 expression level in predicting tumor recurrence within two years after liver resection in patients with HCC was evaluated by survival analysis and Cox multivariable analysis.Results 1. Quantitative real-time PCR revealed that the average expression level of AKR1B10 mRNA in HCC tissues was significantly higher than adjacent non-tumor tissues (P< 0.001). In 80.1% of the entire patients, the relative expression of AKR1B10 mRNA in HCC tissues were higher than their paired adjacent non-tumor tissues. The average expression level of AKR1B10 mRNA in normal liver tissues was significantly lower than adjacent non-tumor tissues (P=0.008). Immunohistochemistry results showed that the protein level of AKR1B10 in HCC tissues was higher than adjacent non-tumor tissues. This result was confirmed in Western blot analysis.2. A total of 28 patients with mutation in codon 249 of the p53 gene in HCC tissues were identified as AFB1 related HCC patients and 84 without it were identified as non-AFB1 related HCC patients. AFB1 related HCC patients had significantly higher AKR1B10 mRNA expression than non-AFB1 related HCC patients in both HCC and adjacent non-tumor tissues (relatively, P=0.012, P= 0.034). Both in AFB1 related HCC patients and non-AFB1 related HCC patients, AKR1B10 mRNA expression in HCC tissues was significantly higher than adjacent non-tumor tissues (all P< 0.001).3. The expression of AKR1B10 mRNA was related to serum alpha-fetoprotein (AFP) and hepatitis B virus (HBV)-DNA levels in this study. In patients with serum AFP level lower than 200ng/ml,63.7% had high expression of AKR1B10 mRNA in HCC tissues, which was significantly higher than in patients with serum AFP of or higher than 200ng/ml (P= 0.048). Among 110 patients with HBV related HCC, the expression of AKR1B10 mRNA in patients who had HBV-DNA level of or higher than 1000IU/ml was significantly higher than that of patients with HBV-DNA level lower than 1000IU/ml (P=0.046). The 6-,12-, and 24-month recurrence rates in patients with low expression of AKR1B10 mRNA were significantly higher than that in patients with high expression of AKR1B10 mRNA (29.2%,64.6%, and 73.4% versus 23.1%,34.5%, and 65:7%, P=0.030). Cox multivariable analysis identified that poor tumor differentiation degree, the largest tumor diameter larger than 5cm, macrovascular invasion, and low expression of AKR1B10 mRNA were independent risk factors for predicting early tumor recurrence in patients with HCC after liver resection.Conclusions AKR1B10 is involved in hepatocarcinogenesis, especially in AFB1 related hepatocarcinogenesis, and is a potential promising biomarker to identify AFB1 related HCC. A low expression level of AKR1B10 mRNA is related to early tumor recurrence in patients with HCC after liver resection.