IMMUNOHISTOCHEMICAL EVIDENCE OF INSULIN-LIKE-GROWTH-FACTOR-II IN HUMAN SMALL HEPATOCELLULAR-CARCINOMA WITH HEPATITIS-C VIRUS-INFECTION - RELATIONSHIP TO FATTY CHANGE IN CARCINOMA-CELLS

It has recently been reported that insulin-like growth factor II (IGF- II) may play a role in the pathogenesis of hepatocellular carcinoma (H CC). We studied the relationship between the expression of IGF-II and fatty change in human small HCC using immunohistochemical staining tec hniques. Liver biopsy specimens were obtained from 35 patients with HC C (consisting of 15 patients with fatty change and 20 patients without fatty change). All patients had serum markers for the hepatitis C vir us (HCV) and histological findings obtained from non-tumourous lesions showed liver cirrhosis or chronic active hepatitis. Immunohistochemic al staining was performed using a monoclonal antibody against rat IGF- II. A positive immunoreaction was found in 69% (24/35) of HCC. Insulin -like growth factor II was immunodetected in 80% (12/15) of HCC with f atty change but only in 60% (12/20) of those without fatty change. In most: cases, IGF-II was not found in hepatocytes from non-tumourous le sions. We believe this to be the first time that IGF-II has been detec ted immunohistochemically in small HCC derived from HCV infection. Thi s growth factor was more frequently immunodetected in HCC with fatty c hange than without. As insulin is an essential factor for the metaboli sm of fatty acids, IGF-LI may play an important role in both fatty deg eneration and in the proliferation of HCC cells. Furthermore, immunohi stochemical IGF-II staining may contribute to the diagnosis of HCC, pa rticularly in early stages accompanied by fatty change.