IMMUNOHISTOCHEMICAL STUDIES OF PROTEIN KINASE D (PKD) 2 EXPRESSION IN MALIGNANT HUMAN LYMPHOMAS
L.M. Kovalevska1, O.V. Yurchenko1, L.M. Shlapatska1,
G.G. Berdova1, S.V. Mikhalap1, J. Van Lint2, S.P.
Sidorenko1, *
1Signal Transductions Laboratory, R.E. Kavetsky Institute of
Experimental Pathology, Oncology and Radiobiology, NAS of Ukraine, Ukraine 2Katholic University of Leuven, Belgium
Abstract. Aim: To study the PKD2 expression, autophosphorylation and
localization in reactive lymph nodes and tumors of lymphoid tissues. Materials and
Methods: Specific antibodies, which recognize PKD1/2 or PKD2 and autophosphorylated
PKD1/2, were used for immunohistochemical and biochemical studies of tonsils, reactive
lymph nodes,tumor samples of non-Hodgkin’s lymphoma (NHL) and Hodgkin’s
lymphoma (HL). Results: Immunohistochemical and biochemical analysis of PKD1 and
PKD2 expression showed PKD2 expression in tonsils, reactive lymph nodes and tumor tissues
from patients with NHL and HL. Furthermore, we were not able to reveal PKD1 expression in
studied lymphoid tissues. In tonsils and reactive lymph nodes the PKD2 expression was
detected in T and B cell zones with highest level in germinal centers of lymphoid
follicles and the maximum level of autophosphorylation in the light zones of the germinal
centers. We found that low level of PKD2 expression and autophosphorylation was
characteristic feature for mantle cell lymphomas, Burkitt’s lymphomas, and in 50% of
CLL/small lymphocytic lymphomas. Lymphoma cells of germinal center origin and with
activated B cell phenotype (diffuse large B cell lymphomas, HL) and anaplastic large cells
lymphoma demonstrated the high level of PKD2 expression and autophosphorylation. Conclusions:
The level of PKD2 expression and autophosphorylation in neoplastic cells corresponds to
the expression pattern of this kinase in their normal analogs, and to the level of cell
differentiation and activation.
