Strong lymphoid nuclear expression of SOX11 transcription factor defines lymphoblastic neoplasms, mantle cell lymphoma and Burkitt's lymphoma.

BACKGROUND We surveyed lymphomas to determine the range of expression of the mantle cell lymphoma-associated SOX11 transcription factor and its relation to cyclin D1. DESIGN AND METHODS On hundred and seventy-two specimens were immunostained for the SOX11 N and C termini. Cyclin D1 was detected by immunohistochemistry and quantitative reverse transcriptase polymerase chain reaction; in situ hybridization for t(11;14) was applied when needed. RESULTS Nuclear SOX11 was strongly expressed in most B and T-lymphoblastic leukemia/lymphomas and half of childhood Burkitt's lymphomas, but only weakly expressed in some hairy cell leukemias. Chronic lymphocytic leukemia/lymphoma, marginal zone, follicular and diffuse large B-cell lymphomas were negative for SOX11, as were all cases of intermediate Burkitt's lymphomas/diffuse large B-cell lymphoma, myeloma, Hodgkin's lymphomas and mature T-cell and NK/T-cell lymphomas. CONCLUSIONS In addition to mantle cell lymphoma, SOX11 is strongly expressed only in lymphoblastic malignancies and Burkitt's lymphomas. Its expression is independent of cyclin D1 (except for weak expression in hairy cell leukemias) and unlikely to be due to translocations in lymphoid neoplasia.