Nuclear BCL-10 expression is common in lymphoplasmacytic lymphoma/Waldenström macroglobulinemia and does not correlate with p65 NF-kappaB activation.
B-cell lymphoma 10 (BCL-10) is expressed in the cytoplasm of normal germinal center and marginal zone B-cells and is involved in lymphocyte development and activation. Aberrant nuclear expression of BCL-10 occurs in a subset of extranodal marginal zone B-cell lymphomas (MALT lymphomas), primarily those with the t(1;14)(p22;q32) or t(11;18)(q21;q21). Little is known about BCL-10 expression in lymphoplasmacytic lymphoma/Waldenström macroglobulinemia (LPL/WM). We assessed for BCL-10 in 51 bone marrow (BM) specimens involved by LPL/WM using immunohistochemical methods. All patients had monoclonal IgM in serum. Extent of BM involvement was assessed using PAX-5/BSAP and CD20 immunostains and the pattern and percentage of B-cells positive for BCL-10 was determined. The p65 subunit of nuclear factor-kappa B (NF-kappaB), a molecule downstream of BCL-10, was also assessed immunohistochemically. Nuclear BCL-10 staining was present in 28/51 (55%) specimens. BCL-10 expression correlated with greater extent of BM involvement (P=0.001), but did not correlate with serum IgM paraprotein levels, type of immunoglobulin light chain, or clinical variables. Nuclear expression of the p65 subunit of NF-kappaB was detected in 17/50 (34%) specimens, suggesting that NF-kappaB is active in a subset of LPL/WM. p65 NF-kappaB activation did not correlate with nuclear BCL-10 immunostaining. Cytogenetic analysis in 29 cases showed no evidence of the t(1;14) or t(11;18). These results indicate that nuclear BCL-10 expression is common in LPL/WM and does not correlate with MALT lymphoma-associated translocations or p65 NF-kappaB nuclear staining.
Merzianu
Mihai
M
Department of Hematopathology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
Jiang
Liuyan
L
Lin
Pei
P
Wang
Xuemei
X
Weber
Donna M
DM
Vadhan-Raj
Saroj
S
Nguyen
Martin H
MH
Medeiros
L Jeffrey
LJ
Bueso-Ramos
Carlos E
CE
D048868:Adaptor Proteins, Signal Transducing / Q000378:metabolism*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000074018:B-Cell CLL-Lymphoma 10 Protein; D001853:Bone Marrow / Q000378:metabolism* / Q000473:pathology; D002467:Cell Nucleus / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism; D005260:Female; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood; D007150:Immunohistochemistry; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000097:blood / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D051996:Transcription Factor RelA / Q000378:metabolism*; D008258:Waldenstrom Macroglobulinemia / Q000097:blood / Q000378:metabolism* / Q000473:pathology
D048868:Adaptor Proteins, Signal Transducing; D000074018:B-Cell CLL-Lymphoma 10 Protein; C118591:BCL10 protein, human; D007075:Immunoglobulin M; C498143:RELA protein, human; D051996:Transcription Factor RelA