Objective    To explore the expression of cathepsin L in hepatocellular carcinoma and to analyze its relationship with clinical and pathological features.     Methods    Fifty-eight specimens of hepatocellular carcinoma were studied

including 18 well-differentiated

18 moderately differentiated and 22 poorly differentiated. Classified by TNM clinical stage

26 were in Ⅰ/Ⅱ stage and 32 in Ⅲ/Ⅳ stage. The expressions of cathepsin L were detected with immunohistochemistry and RT-PCR. Their relationship with the clinical and pathological features of hepatocellular carcinoma was analyzed.     Results    The positive rate of cathepsin L protein was 72.4% (42/58)

and the expressions of cathepsin L protein were significantly different among the specimens of pathological grades of tumor

of TNM clinical stages and with/without metastasis. The positive rate of cathepsin L mRNA was 65.5% (38/58). The expression of cathepsin L mRNA in hepatocellular carcinoma was correlated with pathological grades of tumor

TNM clinical stages and lymph node metastasis.     Conclusion    Cathepsin L plays an important role in the occurrence of hepatocellular carcinoma for its correlation with infiltration and metastasis of hepatocellular carcinoma. Cathepsin L can be used as a useful marker for the prognosis of hepatocellular carcinoma patients.