[Studies on extracellular matrices in rat hepatocarcinogenesis induced by diethylnitrosamine].

Objective: The evolution processes of type IV collagen(CN), fibronectin(FN), and laminin(LN) in carcinogenesis were studied by the use of diethylnitrosamine induced rat hepatocarinogensis model so as to clarify the action of chemical carcinogens on the mechanisms of the occurrence and development of hepatocellular carcinoma.

Methods: Immunohistochemical technigue and image analysis were used to demonstrate the change of the above mentioned three extracellular matrices (ECMs) in histopathological foci.

Results: There were no ECMs expressed in the altered foci, whereas in some neoplastic nodules the ECMs were expressed intensively along the capillarized sinusoid. Cellular morphological analysis showed that in these nodules the average perimeter and the area of the cell increased significantly, but nucleus/cytoplasm ratio decreased significantly as compared with the controls. In the nodules with intensive expression of ECMs, cell proliferation was active, but in the hepatocellular carcinoma these three ECMs diminished or vanished.

Conclusion: The ECMs play an important role in the occurrence and development of hepatocellular carcinoma.