IL-2 inhibits proliferation of K562 cells and reduces accumulation of bcr/abl mRNA and oncoprotein

D. Dilloo, H. Hanenberg, T. Lion, S. Burdach

Research output: Contribution to journalArticle

11 Scopus citations


Cell lines of myeloid origin have been shown to express interleukin-2 receptors (IL-2R). Here, we demonstrate the expression of IL-2Rα and IL-Rβ on the CML blast cell line K562 by FACS analysis and cross-linking assay. Furthermore, we examined the effect of IL-2 on leukemic progenitor growth, employing K562 as a model. Clonogenic growth was assessed after 3 days of culture by colony formation in a serum free, semi-solid assay system. IL-2 was found to exhibit a dose-dependent suppressive effect on K562 clonogenicity with 48% inhibition of colony formation at 250 U IL-2 and 60% inhibition at 1000 U IL-2. Philadelphia chromosome (Ph)-positive K562 cells possess multiple copies of the bcr/abl fusion gene whose transcript and protein product (p210) is thought to confer growth advantage to CML cells. We therefore investigated IL-2-dependent modulation of bcr/abl mRNA accumulation and p210 protein levels in K562 cells. After 4 h of culture in the presence of IL-2, a 3-15-fold reduction of bcr/abl mRNA accumulation was demonstrated by competitive reverse PCR. Reduction of bcr/abl fusion protein levels was demonstrated at 24 h of IL-2-supplemented cell culture, employing p210 recognizing monoclonal antibodies (mAbs) in FACS analysis. Levels of proliferation marker Ki67 were only marginally affected. We conclude: (1) K562 cells express both IL-2Rα and IL-Rβ; (2) IL-2 inhibits clonogenic growth of K562 in a dose-dependent manner; and (3) IL-2-mediated inhibition of K562 proliferation is preceded by a reduction of bcr/abl mRNA accumulation and p210 protein levels.

Original languageEnglish (US)
Pages (from-to)419-424
Number of pages6
Issue number3
StatePublished - Mar 1995



  • CML
  • Interleukin-2
  • bcr/abl
  • p210

ASJC Scopus subject areas

  • Hematology
  • Oncology
  • Cancer Research

Cite this

Dilloo, D., Hanenberg, H., Lion, T., & Burdach, S. (1995). IL-2 inhibits proliferation of K562 cells and reduces accumulation of bcr/abl mRNA and oncoprotein. Leukemia, 9(3), 419-424.