Expression of LMO2 is associated with t(14;18)/IGH-BCL2 fusion but not BCL6 translocations in diffuse large B-cell lymphoma.
Diffuse large B-cell lymphoma (DLBCL) can be separated for prognostic purposes using gene expression profiling (GEP) into 2 subgroups: germinal center B-cell (GCB) and activated B-cell phenotypes. However, GEP is impractical for routine clinical use, and immunophenotyping is an imperfect surrogate. Therefore, we studied the relationship between expression of the purported germinal center marker LMO2 and the presence of IGH-BCL2 fusions, BCL6 translocations, and LMO2 translocations. In addition, we investigated the usefulness of LMO2 expression as a marker of GCB subtype in DLBCL. Immunohistochemical and fluorescence in situ hybridization studies were successfully performed on 101 cases of de novo DLBCL that had been incorporated into a tissue microarray. There was a statistically significant association between IGH-BCL2 fusion and LMO2 protein expression (P = .02) but not between BCL6 translocations and LMO2 expression. LMO2 translocations were not identified. Although uncommon, all cases that had both IGH-BCL2 fusion and BCL6 translocations expressed LMO2. The findings suggest LMO2 as a potential marker for the GCB phenotype.
Durnick
David K
DK
Dept. of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA.
Law
Mark E
ME
Maurer
Matthew J
MJ
Natkunam
Yasodha
Y
Levy
Ronald
R
Lossos
Izidore S
IS
Kurtin
Paul J
PJ
McPhail
Ellen D
ED
D048868:Adaptor Proteins, Signal Transducing; D014408:Biomarkers, Tumor / Q000032:analysis*; D002883:Chromosomes, Human, Pair 14 / Q000235:genetics; D002885:Chromosomes, Human, Pair 16 / Q000235:genetics; D004268:DNA-Binding Proteins / Q000096:biosynthesis*; D015870:Gene Expression; D020869:Gene Expression Profiling; D050438:Genes, Immunoglobulin Heavy Chain / Q000235:genetics*; D019254:Genes, bcl-2 / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D060588:LIM Domain Proteins; D016403:Lymphoma, Large B-Cell, Diffuse / Q000235:genetics* / Q000378:metabolism; D008667:Metalloproteins / Q000096:biosynthesis*; D015514:Oncogene Proteins, Fusion; D011518:Proto-Oncogene Proteins; D051560:Proto-Oncogene Proteins c-bcl-6 / Q000235:genetics*; D046888:Tissue Array Analysis; D014178:Translocation, Genetic
D048868:Adaptor Proteins, Signal Transducing; D014408:Biomarkers, Tumor; D004268:DNA-Binding Proteins; D060588:LIM Domain Proteins; C085117:LMO2 protein, human; D008667:Metalloproteins; D015514:Oncogene Proteins, Fusion; D011518:Proto-Oncogene Proteins; D051560:Proto-Oncogene Proteins c-bcl-6