M. Taniai et al., IMMUNOHISTOCHEMICAL DETECTION OF PROLIFERATING CELL NUCLEAR ANTIGEN IN HEPATOCELLULAR-CARCINOMA - RELATIONSHIP TO HISTOLOGICAL GRADE, Journal of gastroenterology and hepatology, 8(5), 1993, pp. 420-425
Proliferating cell nuclear antigen (PCNA), also known as cyclin, is an
auxiliary protein of DNA polymerase-delta and is found only in the nu
clei of proliferating cells in the late G1 and S phases. The prolifera
tion of hepatocellular carcinoma (HCC) by immunohistochemical staining
for PCNA using paraffin sections of 20 surgically resected HCC specim
ens was analysed. The mean percentage of PCNA-positive nuclei in the H
CC tissue was 10.3% in grade I of Edmondson and Steiner's classificati
on, 25.5% in grade II, 28.4% in grade III and 41.5% in grade IV. In ea
rly HCC, we observed only a few PCNA-positive tumour cells. However, P
CNA-positive nuclei were numerous in the tumour thrombi found in porta
l vein branches, in regions of extracapsular tumour growth, and in the
inner nodules of tumours with a nodule-in-nodule formation. Prolifera
ting cell nuclear antigen positivity was correlated with an increase o
f the nucleocytoplasmic ratio of tumour cells as determined by image a
nalysis. Our findings showed that PCNA positivity was correlated with
the histological grade and invasiveness of HCC, suggesting that this a
ntigen may be used as an indicator to predict tumour invasion in patie
nts with HCC.