Objective: To reveal intrahepatic metastasis of hepatocellular carcinoma (HCC) in relation to its micro-environment and nm23-H1 H-ras mRNA expression.
Methods: In HCC specimens from 25 patients, the level of nm23-H1 and H-ras mRNA was examined by quantitative reverse transcription-polymerase chain reaction(RT-PCR). Tumor microvessel density(MDV), an essential factor of microenvironment and proliferating cell nucleus antigen (PCNA), an index of tumor cell proliferation, were also studied by immunohistochemical methods using antibodies against endothelial protein factor VIII-related antigen(F8RA) and antibody PC-10.
Results: The MDV and PCNA index in the group with intrahepatic metastasis were remarkably higher than those in the group without it (P < 0.01), while nm23-H1 mRNA expression level was negatively correlated with PCNA index (P < 0.05). The level of H-ras mRNA expression did not correlate with intrahepatic metastasis. MDV was positively correlated with PCNA index (P < 0.01).
Conclusion: Intrahepatic metastasis of HCC depends very much on its in situ microenvironment. The decline in nm23-H1 mRNA may implicate a preferential proliferation of nm23-negetive HCC cells with highly metastastic potential which adapt well to the microenvironment.