Follicular dendritic cell-induced microRNA-mediated upregulation of PRDM1 and downregulation of BCL-6 in non-Hodgkin's B-cell lymphomas

Leukemia. 2011 Jan;25(1):145-52. doi: 10.1038/leu.2010.230. Epub 2010 Oct 22.

Abstract

B-cell lymphoma 6 (BCL6) and PR domain containing 1 (PRDM1) are considered as master regulators for germinal center (GC) formation and terminal B-cell differentiation. Dysregulation of BCL6 and PRDM1 has been associated with lymphomagenesis. Here, we show for the first time that direct cell-cell contact between follicular dendritic cells (FDC) and B-lymphocytes, by influencing the expression of a set of microRNAs (miRNAs), regulates the expression of BCL6 and PRDM1. We identify that, on cell adhesion to FDC, FDC induces upregulation of PRDM1 expression through downregulation of miR-9 and let-7 families and induces downregulation of BCL-6 through upregulation of miR-30 family in B-lymphocytes and lymphoma cells. We further demonstrate that the miR-30 family directly controls BCL-6 expression and miR-9-1 and let-7a directly control PRDM-1 expression through targeting their 3'UTR, mediating the FDC effect. Our studies define a novel regulatory mechanism in which the FDC, through induction of miRNAs in B-lymphocytes, orchestrates the regulation of transcription factors, promotes germinal center B-cell survival and differentiation. Dysregulation of miRNAs may interfere with B-cell survival and maturation, thus representing a novel molecular mechanism, as well as a potential therapeutic target in B-cell lymphomas.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions / physiology
  • Cell Communication
  • Cell Line, Tumor
  • Cell Survival
  • DNA-Binding Proteins / genetics*
  • Dendritic Cells, Follicular / physiology*
  • Down-Regulation
  • Humans
  • Lymphoma, B-Cell / metabolism*
  • MicroRNAs / physiology*
  • Positive Regulatory Domain I-Binding Factor 1
  • Proto-Oncogene Proteins c-bcl-6
  • Repressor Proteins / genetics*
  • Up-Regulation

Substances

  • 3' Untranslated Regions
  • BCL6 protein, human
  • DNA-Binding Proteins
  • MicroRNAs
  • Proto-Oncogene Proteins c-bcl-6
  • Repressor Proteins
  • mirnlet7 microRNA, human
  • PRDM1 protein, human
  • Positive Regulatory Domain I-Binding Factor 1