Because the LMP gene has transforming potential, our findings support the concept of a pathoetiologic role for EBV in a proportion of CD30-positive ALC lymphomas.
In the present paper we report on 12 further neoplasms with a translocation involving the 5q35 breakpoint and show that all were large cell lymphomas expressing the CD30 (Ki-1) antigen, often classifiable histologically as 'Ki-1 lymphoma'.
Immunophenotyping and immunogenotyping were performed in a series of 8 large cell lymphomas exhibiting anaplastic or "histiocytic" morphology and displaying an uncertain phenotype due to a restricted number of differentiation antigens.6 cases expressed the Ki-1 antigen.
Large cell anaplastic lymphomas positive for the activation antigen CD 30 also contain rearrangement in about one-half (five of 11) of the tumors examined.
In agreement with cytogenetic analyses, but at variance with recently published studies, ALK gene expression distinguishes a subset of ALC lymphomas from other CD30+ lymphomas, including HD.
Morris et al., Science (Washington DC), 263: 1281-1284, 1994] is associated with Ki-1 (CD30)-positive anaplastic large cell lymphomas (ALCL); a group of morphologically and immunophenotypically heterogenous high grade large cell lymphomas (LCL), which share many characteristics with Hodgkin's disease (HD), including the presence of variable numbers of Reed-Sternberg-like cells and the expression of CD30 antigen.
The results of this study indicate that Epstein-Barr virus genomes might be identified in more than 50% of the evaluated high grade non-Hodgkin's lymphomas; this association occurred significantly more often in the small noncleaved cell lymphomas resembling endemic Burkitt's lymphoma (60%) and with ALC CD30/BerH2+ lymphomas (77.8%).
The Epstein-Barr virus has been implicated in the etiology of endemic Burkitt's lymphoma, post-transplant lymphoma, large-cell anaplastic CD30 (Ki-1)-positive lymphoma, and in many T-cell lymphomas.
However, the majority of CD26-expressing cases clustered in the lymphoblastic lymphomas (LBL)/T-acute lymphoblastic leukemias (ALL; 12/23) and CD30+ anaplastic large-cell (ALC) lymphomas (5/8), whereas CD40L+ lymphomas included a large fraction of mycosis fungoides (11/21 [52%]).
A loss of response to transforming growth factor-beta, which normally dampens cellular proliferation, may differentiate CD30+ lymphoma from lymphomatoid papulosis.
The CD30-CD30 ligand interaction could have a critical pathophysiological role in malignant lymphomas, particularly Hodgkin disease, large cell anaplastic lymphomas and Burkitt lymphomas, and is also involved in activation and functioning of the T cell-dependent immune system.
Expression of NCAM could be regarded as responsible, in part, for the extranodal localization of lymphoma cells; expression of CD56 also might contribute to the definition of a subset of CD30+ lymphomas with distinctive clinicopathologic features.