title: High rate of neoplastic cells with genetic abnormalities in proliferation centers of chronic lymphocytic leukemia.
abstract: In lymph nodes, chronic lymphocytic leukemia (CLL) cells (prolymphocytes and paraimmunoblasts) form proliferation centers (PCs), which are also known as pseudofollicles. To reveal whether PCs play a role in the accumulation of genetic alterations in CLL, we compared deletion at 11q22.3, 13q14.3, and 17p13.1 loci and trisomy 12 by the fluorescence in situ hybridization (FISH) technique in PCs versus surrounding small lymphocytes (SLs) in 12 formalin-fixed paraffin-embedded (FFPE) lymph nodes. The FFPE sections were stained with methylene blue and PCs were marked by laser beam. Subsequent FISH analysis was performed, relocalizing the previously defined regions. Loss of 11q was detected in five cases, loss of 13q in two cases, loss of 17p in two cases, and trisomy 12 in one case. In seven cases PCs contained a significantly higher ratio of cells with genetic alterations compared with the surrounding SLs. Our results show that CLL cells with genetic alterations tend to accumulate in PCs. The clonal expansion of the cell population carrying genetic alterations within PCs may contribute to CLL progression.
authors.affiliation: 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary.
authors.forename: Zsófia
authors.initials: Z
authors.lastname: Balogh
authors.forename: Lilla
authors.initials: L
authors.lastname: Reiniger
authors.forename: Hajnalka
authors.initials: H
authors.lastname: Rajnai
authors.forename: Judit
authors.initials: J
authors.lastname: Csomor
authors.forename: Agota
authors.initials: A
authors.lastname: Szepesi
authors.forename: Anikó
authors.initials: A
authors.lastname: Balogh
authors.forename: Linda
authors.initials: L
authors.lastname: Deák
authors.forename: Eva
authors.initials: E
authors.lastname: Gagyi
authors.forename: Csaba
authors.initials: C
authors.lastname: Bödör
authors.forename: András
authors.initials: A
authors.lastname: Matolcsy
mesh_terms: D049109:Cell Proliferation; D002869:Chromosome Aberrations; D002872:Chromosome Deletion; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D002881:Chromosomes, Human, Pair 12 / Q000235:genetics; D002882:Chromosomes, Human, Pair 13 / Q000235:genetics; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics* / Q000473:pathology; D008198:Lymph Nodes / Q000378:metabolism* / Q000473:pathology; D008214:Lymphocytes / Q000378:metabolism / Q000473:pathology; D014314:Trisomy