Granulocytic differentiation of HL-60 cells results in spontaneous apoptosis mediated by increased caspase expression

FEBS Lett. 1997 Aug 4;412(3):603-9. doi: 10.1016/s0014-5793(97)00779-5.


HL-60 cells differentiating into neutrophil-like cells die an apoptotic death in vitro. Susceptibility to apoptosis is associated with decreased Bcl-2 protein and mRNA expression; however, the effect of differentiation on the expression of pro-apoptotic caspases is unknown. Spontaneous apoptosis occurred 6 days after retinoic acid treatment. Western blotting showed loss of Bcl-2 by day 7, and new expression of ICE (caspase 1) and CPP32 (caspase 3) protein by day 2. Northern analysis demonstrated loss of Bcl-2 mRNA and increases in ICE mRNA by day 2; CPP32 mRNA was unchanged. Differential Bcl-2 and ICE mRNA expression was also found when granulocytic differentiation was stimulated by DMSO. Differentiated HL-60 cell lysates exhibited functional ICE proteolytic activity. De novo caspase expression was responsible for the development of spontaneous apoptosis, since specific inhibitors of ICE (YVAD-CMK) and CPP32 (DEVD-CHO), inhibited retinoic acid induced spontaneous apoptosis. Functional maturation and susceptibility to apoptosis are both inducible and linked in this granulocyte precursor cell line.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis* / drug effects
  • Apoptosis* / genetics
  • Caspase 1
  • Cell Differentiation / drug effects
  • Cysteine Endopeptidases / biosynthesis*
  • Cysteine Endopeptidases / drug effects
  • Cysteine Endopeptidases / physiology
  • Cysteine Proteinase Inhibitors / pharmacology
  • Granulocytes / cytology*
  • Granulocytes / drug effects
  • Granulocytes / enzymology*
  • HL-60 Cells
  • Humans
  • Neutrophils / enzymology
  • Neutrophils / physiology
  • Proto-Oncogene Proteins c-bcl-2 / biosynthesis
  • RNA, Messenger / biosynthesis
  • Signal Transduction
  • Tretinoin / pharmacology
  • fas Receptor / physiology


  • Cysteine Proteinase Inhibitors
  • Proto-Oncogene Proteins c-bcl-2
  • RNA, Messenger
  • fas Receptor
  • Tretinoin
  • Cysteine Endopeptidases
  • Caspase 1