Expression of the Class II and III Beta-Tubulin in Neoplastic and Non-Neoplastic Lymphoid Tissues

Aim: Abnormal expression patterns of beta-tubulin isotypes may provide a molecular rationale for the behaviour
of lymphoma subtypes. In the present study class II and III beta-tubulin expression was assessed in non-neoplastic and
neoplastic lymphoid tissues with reference to potential utility as new tumour biomarkers. Methods and results: In this
cross-sectional study class II and III beta-tubulin expression was assessed in 304 neoplastic and 20 normal lymphoid
tissues using qualitative and semi-quantitative immunohistochemistry. Class II beta-tubulin was found to be positive in
the germinal centres, mantle zone and interfollicular regions of normal lymphoid tissues. It was also expressed in 15/15
(100%) lymphoblastic lymphomas, 229/231 (99%) mature B cell lymphomas, 22/22 (100%) T/NK-cell lymphomas and
36/36(100%) classical Hodgkin lymphomas. Class III beta-tubulin in contrast was germinal centre restricted and more
selective, being found mainly in classical Hodgkin lymphomas (34/36 (94%)). It was also expressed in 58/171(34%)
DLBCL, 11/12 (92%) mantle cell lymphomas and 6/6 (100%) Burkitt lymphomas. Other mature B cell, T/NK cell
lymphomas and precursor lymphoblastic lymphomas were usually negative. Conclusions: Class II beta-tubulin shows
ubiquitous expression in neoplastic and non-neoplastic lymphoisd tissues. In contrast, Class III beta-tubulin is germinal
centre-restricted. Its consistent expression in classical Hodgkin lymphomas may point to use in the identification of
Reed-Sternberg and Hodgkin cells. Its expression in a proportion of DLBCL, Burkitt and mantle cell lymphomas is of
interest as this may be related to their aggressiveness.