Factors involved in CLL pathogenesis and cell survival are disrupted by differentiation of CLL B-cells into antibody-secreting cells

Oncotarget. 2015 Jul 30;6(21):18484-503. doi: 10.18632/oncotarget.3941.

Abstract

Recent research has shown that chronic lymphocytic leukemia (CLL) B-cells display a strong tendency to differentiate into antibody-secreting cells (ASCs) and thus may be amenable to differentiation therapy. However, the effect of this differentiation on factors associated with CLL pathogenesis has not been reported. In the present study, purified CLL B-cells were stimulated to differentiate into ASCs by phorbol myristate acetate or CpG oligodeoxynucleotide, in combination with CD40 ligand and cytokines in a two-step, seven-day culture system. We investigated (i) changes in the immunophenotypic, molecular, functional, morphological features associated with terminal differentiation into ASCs, (ii) the expression of factors involved in CLL pathogenesis, and (iii) the expression of pro- and anti-apoptotic proteins in the differentiated cells. Our results show that differentiated CLL B-cells are able to display the transcriptional program of ASCs. Differentiation leads to depletion of the malignant program and deregulation of the apoptosis/survival balance. Analysis of apoptosis and the cell cycle showed that differentiation is associated with low cell viability and a low rate of cell cycle entry. Our findings shed new light on the potential for differentiation therapy as a part of treatment strategies for CLL.

Keywords: B-cell differentiation; LEF1; ROR1; apoptosis; chronic lymphocytic leukemia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibody-Producing Cells / drug effects
  • Antibody-Producing Cells / immunology*
  • Antibody-Producing Cells / metabolism
  • Apoptosis / drug effects
  • Apoptosis / genetics
  • Apoptosis / immunology
  • B-Lymphocytes / drug effects
  • B-Lymphocytes / immunology*
  • B-Lymphocytes / metabolism
  • CD40 Ligand / pharmacology
  • Cell Culture Techniques
  • Cell Cycle / drug effects
  • Cell Cycle / genetics
  • Cell Cycle / immunology
  • Cell Differentiation / drug effects
  • Cell Differentiation / genetics
  • Cell Differentiation / immunology*
  • Cell Survival / drug effects
  • Cell Survival / genetics
  • Cell Survival / immunology
  • Cells, Cultured
  • Cytokines / pharmacology
  • Enzyme-Linked Immunosorbent Assay
  • Gene Expression / drug effects
  • Gene Expression / genetics
  • Gene Expression / immunology
  • Humans
  • Immunoblotting
  • Immunoglobulin Isotypes / immunology
  • Immunoglobulin Isotypes / metabolism
  • Immunophenotyping
  • Inhibitor of Apoptosis Proteins / genetics
  • Inhibitor of Apoptosis Proteins / immunology
  • Inhibitor of Apoptosis Proteins / metabolism
  • Leukemia, Lymphocytic, Chronic, B-Cell / genetics
  • Leukemia, Lymphocytic, Chronic, B-Cell / immunology*
  • Leukemia, Lymphocytic, Chronic, B-Cell / metabolism
  • Lymphoid Enhancer-Binding Factor 1 / genetics
  • Lymphoid Enhancer-Binding Factor 1 / immunology
  • Lymphoid Enhancer-Binding Factor 1 / metabolism
  • Oligodeoxyribonucleotides / pharmacology
  • Reverse Transcriptase Polymerase Chain Reaction
  • Survivin
  • Tetradecanoylphorbol Acetate / pharmacology

Substances

  • BIRC5 protein, human
  • CPG-oligonucleotide
  • Cytokines
  • Immunoglobulin Isotypes
  • Inhibitor of Apoptosis Proteins
  • LEF1 protein, human
  • Lymphoid Enhancer-Binding Factor 1
  • Oligodeoxyribonucleotides
  • Survivin
  • CD40 Ligand
  • Tetradecanoylphorbol Acetate