PROLIFERATING CELL NUCLEAR ANTIGEN, KI-67, C-MYC P62 ONCOPROTEIN, ANDNUCLEOLAR ORGANIZER REGIONS IN HODGKINS-DISEASE

The expression of four proliferation-associated markers-proliferating cell nuclear antigen (PCNA), Ki-67, c-myc p62 oncoprotein, and nucleol ar organizer regions (NORs)-in a series of 156 cases of Hodgkin's dise ase was assessed. Paraffin sections were stained immunohistochemically using the avidin-biotin method and the monoclonal antibodies PC-10, K i-67, and c-myc 1-9E10 and histochemically with a silver nitrate (AgNO Rs) technique. All cases were also stained immunohistochemically for t he CD30 antigen. The PCNA immunoreactivity was observed in neoplastic (Hodgkin and Reed-Sternberg) cells in all cases and was predominantly nuclear, but in half of the cases cytoplasmic positivity was also seen . Ki-67 was expressed by Hodgkin and Reed-Sternberg cells in all cases with a nuclear and nucleolar pattern. However, in 71% of the cases so me cytoplasmic staining was also seen. C-myc p62 was detected in neopl astic cells in 98.68% of the cases. The pattern of staining was mainly cytoplasmic. Neither PC-10 nor Ki-67 nor c-myc 1-9E10 showed a predil ection for any histological type. The mean number of AgNORs per neopla stic cell ranged from 1.40 to 7.40 and was significantly lower in the lymphocyte-predominant type (p < 0.05). No correlation was found betwe en the expression of PCNA, Ki-67, c-myc p62, CD30, and the number of A gNORs apart from a weak correlation between PCNA and CD30 (r = 0.247, p < 0.01) and between Ki-67 and c-myc 1-9E10 (r 0.348, p < 0.001). The se results confirm the high proliferation rate as well as the elevated c-myc p62 expression in Hodgkin and Reed-Sternberg cells, indicating that the c-myc oncogene may be involved in the pathogenesis of Hodgkin 's disease. Our findings also show a unique immunophenotype of the neo plastic cells in Hodgkin's disease as compared to non-Hodgkin's lympho mas.