EXPRESSION OF CLASSICAL PROTEIN-KINASE-C SUBSPECIES IN NONNEOPLASTIC LYMPHOCYTES AND NON-HODGKINS-LYMPHOMAS - AN IMMUNOHISTOCHEMICAL STUDY

it is generally accepted that phosphorylation plays a pivotal role in the cellular response of cell differentiation and proliferation. Immun ohistochemical expression of classical protein kinase C (cPKC) subspec ies (alpha, beta and gamma) in eight reactive lymphoid tissues, three normal spleens and 149 non-Hodgkin's lymphomas was examined. cPKC beta was observed primarily in the mantle zone B cells, but appeared as ve ry faint staining in Ki-67 positive proliferated a cells in the germin al centers of secondary lymph follicles. In contrast to the reactive s tate, high levels of cPKC subspecies were recognized in the majority o f 149 cases of non-Hodgkin's lymphoma, including those thought to have arisen from germinal center cells such as follicular lymphoma, The ex pression of cPKC alpha was found in higher frequency in T cell lymphom as than B cell lymphomas (P<0.01) by the Chi-squared test. High levels of cPKC alpha were present only in high grade or highly aggressive ly mphomas, showing the highest incidence in the small noncleaved cell ty pe, according to the International Working Formulation and National Ca ncer Institute (P < 0.01), cPKC gamma was not detected in normal lymph oid cells and was expressed in only four cases of non-Hodgkin's lympho mas, It is presumed that cPKC alpha and beta have a relationship to ce ll activation and proliferation of lymphoid cells of reactive and neop lastic states. It might be considered that the expression of cPKC alph a may have a relationship with aggressiveness in non-Hodgkin's lymphom as.