Class III beta-tubulin shows unique expression patterns in a variety of neoplastic and non-neoplastic lymphoproliferative disorders.

Class III beta-tubulin (TUBB3) expression in carcinoma is associated with resistance to tubulin-binding chemotherapeutic agents. Recently, follicular dendritic cells (FDCs) were reported to express TUBB3 under physiologic conditions. We investigated TUBB3 expression in a wide range of lymphoproliferative disorders using immunohistochemistry. Dual immunostaining for Bcl-6 and TUBB3 revealed that some germinal center B cells also express TUBB3 in addition to FDCs. In Hodgkin lymphomas (HLs), 47.1% (40/85) expressed TUBB3 in the tumor cells with an all-or-none pattern. TUBB3 expression in HL was more common in mixed cellularity type than nodular sclerosis type (P=0.032). Among non-HLs, 79.3% (23/29) of anaplastic large cell lymphoma (ALCL), 8% (2/25) of extranodal natural killer/T-cell lymphoma, and 75% (21/28) of Burkitt lymphoma showed TUBB3 expression with an all-or-none pattern. Of diffuse large B-cell lymphoma, 15.2% (32/210) expressed TUBB3 in a heterogeneous pattern. In ALCL, TUBB3 expression was more common in systemic ALCL than in primary cutaneous ALCL (P=0.046). Diffuse large B-cell lymphomas with a germinal center B-like subgroup exhibited TUBB3 expression more frequently than non-GCB-like subgroup (P=0.01). Otherwise, none of the 18 angioimmunoblastic T-cell lymphomas; 18 peripheral T-cell lymphomas, not otherwise specified; 12 follicular lymphomas; 62 marginal zone lymphomas; 7 mantle cell lymphomas; 8 small lymphocytic lymphomas; or 2 FDC sarcomas expressed TUBB3. In angioimmunoblastic T-cell lymphoma and Castleman disease, TUBB3 was positive in immunoblasts corresponding to Epstein-Barr virus-infected or Kaposi sarcoma herpes virus-infected cells. A variety of neoplastic and non-neoplastic lymphoproliferative disorders exhibited characteristic TUBB3 expression patterns; these results suggest potential for diagnostic utility, some insight into the pathobiology of TUBB3 expression, and potential therapeutic implications.