Expression and Clinical Significance of OX40 and OX40L mRNA in Hepatocellular Carcinoma

In a retrospective study, the expression of mRNA of membrane receptor OX40 and its ligand OX40L in liver tissues was analyzed in 34 patients with hepatocellular carcinoma in order to assess their clinical implications and prognostic value. Expression of mRNA was analyzed by reverse transcription PCR and TaqMan probes. Expression of OX40 mRNA was significantly higher in tumor specimens in paired comparison with the samples of adjacent non-tumor tissue or normal liver tissue of control patients. In contrast, expression of OX40L mRNA was lower in tumor tissue in paired comparison with the samples of adjacent non-tumor tissue or normal liver tissue. The clinical and pathological analysis showed that expression of OX40 mRNA significantly correlated with the degree of tumor differentiation; there was an insignificant decreasing trend in the length of recurrence-free period. It was hypothesized that microenvironment of hepatocellular carcinoma can induce immunosuppression due to dysregulation of the expression of OX40 and OX40L in tumor tissue, which promotes tumor growth.