Immunohistochemical Investigation on Expression of Hepatitis B Surface Antigen, Transforming Growth Factor-alpha, and Proliferating Cell Nuclear Antigen in Hepatocellular Carcinoma

ABSTRACT

In an attempt to evaluate the expression of hepatitis B surface antigen(HBs Ag), transforming growth factor-ct(TGF-alpha), and proliferating cell nuclear antigen(PCNA) in hepatocellular carcinoma(HCC), an immunohistochemical investigation(ABC method) was performed using 31 surgically resected HCCS. The authors examined the expression rate and patterns, histopathologic correlation, and inter-relationships among these expressions. The results were summarized as follows. 1) Among 25 seropositive HCCS, 15 cases showed tissue expression of HBs Ag(60.0%), being expressed as a predominantly cytoplasmic pattern. Its expression rate in low grade HCC was significantly high(76.9%), in contrast to a low rate in high grade HCC(41.7%)(P<0.05). Adjacent nonenoplatic tissue showed a higher expression rate(82.6%). 2) TGF-alpha was expressed in 23 of 31 cases of HCC(74.3%). The intensity and extent of its expression did not correlate tyros with histopathologic features. Bile duct epithelium, juxtaposed and/or entrapped liver cells, and cirrhotic nodules were variably expressed, of which intense peripheral reaction within the nodules was frequently noted. 3) PCNA was expressed throughout the neoplastic tissue of HCC. Its index was significantly high(34.4 13.6), being compared to low index index(3.5 2. 1) in the nonneoplastic tissue(P<0.005). High grade tumors revealed a higher index than the low grade tumors(P<0.05). Conclusively, this data confirms that PCNA index offers useful information about cell proliferation associated with histologic degrees of malignancy of HCC, albeit TGF-alpha is also involved in cellular proliferation of both liver cell and bile duct epithelium. Changes in incidence and cellular localization of HBs Ag expression between the neoplastic and nonneoplastic tissues suggest that an integrated viral genome could be functionally altered during hepatocarcinogenesis. A significant inter-relationship among these expressions was not observed.