Proliferative and apoptotic activity in hepatocellular carcinoma and surrounding non-neoplastic liver tissue

The aim of the study was to determine the proliferative and apoptotic activ ity of neoplastic and nonneoplastic hepatocytes, to ascertain whether there was a correlation between the histopathological characteristics of hepatoc ellular carcinoma (HCC) and its proliferative or apoptotic activity, Methods. One tumour sample and one sample of nonneoplastic liver from 16 pa tients with HCC were analysed. The proliferative activity was established b y immunohistochemical staining against PCNA (proliferating cell nuclear ant igen) and Ki-67. Apoptotic activity was determined by morphological and TUN EL methods. Bcl-2 immunoreactivity was analysed. Results. A positive correlation between PCNA and Ki-67 proliferative indexe s was found in HCC (p <0.01). The PCNA index was 0.21% +/- 0.80% (Mean SD) in nonneoplastic liver and 7.41% +/- 8.22% in HCC, while the Ki-67 index wa s 0.19% +/- 0.26% in non-neoplastic liver and 9.67% +/- 7.70% in HCC. The d ifferences between HCC and non-neoplastic liver were significant (p <0.05). The PCNA index differed significantly between different HCC grades (p <0.0 5). In HCC and non-neoplastic liver samples, apoptotic indexes (AI) assesse d morphologically were higher than AI determined by the TUNEL method. Diffe rences in Al (irrespective of the method used) between different HCC grades were not significant. Bcl-2 staining was positive in one non-neoplastic li ver sample (6.3%) and in 4 HCC samples (25%). Conclusions. PCNA and Ki-67 were useful for proliferative activity assessme nt of hepatocytes. There were no differences in apoptotic activity between HCC and nonneoplastic tissue, so it seems that uncontrolled tumour cell div ision plays an important role in HCC growth. In the regulation of the apopt otic process in HCC, Bcl-2 could be important.