Real-time Reverse Transcription PCR Analysis for Validation of Transketolase Gene in Hepatocellular Carcinoma Tissues

Hepatocellular carcinoma (HCC) is the most common malignant tumor in the adult liver, with high relapse and mortality rates despite diverse treatment modalities. In this study, expression of transketolase (TKT) and transketolase-like 1 (TKTL1) gene, coding for the rate-limiting enzyme in non-oxidative pentose phosphate pathway (PPP), was investigated as a potential prognostic factor of HCC. The expression level of TKT and TKTL1 gene was measured by real-time reverse-transcription PCR (RT-PCR) in 185 primary HCCs and 49 non-cancerous surrounding livers. TKT mRNA level was markedly elevated in HCCs compared to non-cancerous surrounding tissues (P < 0.0001). On the other hand, TKTL1 mRNA level was higher in HCCs compared to non-cancerous surrounding tissues but the difference was not statistically significant. TKT expression in tumors was significantly correlated with several clinicopathologic parameters including tumor size and Edmondson grade. Moreover, patients who expressed higher TKT mRNA levels had a significantly shorter overall survival (OS) time (P = 0.00099) and a significantly shorter disease-free survival (DFS) time (P = 0.0055). In a multivariate analysis, high TKT expression was found to be an independent prognostic factor for OS both as a discrete variable (P = 0.009) and as a continuous variable (P = 0.0068). The results of this study indicated that TKT gene expression is a significant prognostic factor for OS in HCC cases. Therefore, TKT merits further investigation regarding its role as a prognostic factor with a larger cohort of HCC patients.