In a patient with biclonal Waldenstrom macroglobulinemia only one clone expands in three-dimensional culture and includes putative cancer stem cells.
A small percentage of cases of Waldenstrom macroglobulinemia (WM) present with biclonality, defined here as the rearrangement of two distinct VDJ gene segments. Here we investigated the expansion of two clones from a patient with WM expressing molecularly detectable clonotypic gene rearrangements, one V(H)3 and one V(H)4. Biclonality was determined in blood and bone marrow mononuclear cells using real-time quantitative PCR (RQ-PCR). V(H)4 expressing cells but not V(H)3 expressing cells underwent clonal expansion in 3-D culture of reconstructed WM bone marrow. After 3-D culture, secondary culture in a colony forming unit assay, and RQ-PCR, only the V(H)4 clone was shown to harbor a subpopulation with characteristics of cancer stem cells, including proliferative quiescence, self-regeneration, and the ability to generate clonotypic progeny, suggesting that the V(H)4, but not the V(H)3, clone is clinically significant. Enrichment of potential WM stem cells in 3-D cultures holds promise for monitoring their response to treatment and for testing new therapies.
Department of Oncology, University of Alberta and Cross Cancer Institute, Edmonton, Alberta, Canada.
Julia
J
Kirshner
Kyle J
KJ
Thulien
Jitra
J
Kriangkum
Sarah
S
Motz
Andrew R
AR
Belch
Linda M
LM
Pilarski
D000368:Aged; D001402:B-Lymphocytes / Q000473:pathology; D018929:Cell Culture Techniques; D019070:Cell Lineage; D002999:Clone Cells; D003114:Colony-Forming Units Assay; D005260:Female; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain / Q000235:genetics*; D050438:Genes, Immunoglobulin Heavy Chain / Q000235:genetics*; D006801:Humans; D007075:Immunoglobulin M / Q000235:genetics; D014411:Neoplastic Stem Cells / Q000473:pathology*; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured; D008258:Waldenstrom Macroglobulinemia / Q000235:genetics*
D007075:Immunoglobulin M; D012333:RNA, Messenger