Combination toxicity of etoposide (VP-16) and photosensitisation with a water-soluble aluminium phthalocyanine in K562 human leukaemic cells

Br J Cancer. 1996 Nov;74(10):1570-7. doi: 10.1038/bjc.1996.591.


Etoposide (VP-16) is an anti-cancer drug commonly used against several types of tumours and leukaemia, either alone or in combination chemotherapy. Photodynamic therapy (PDT) is another, relatively new modality for treatment of various malignancies. The interactions between VP-16 and PDT, using aluminium tetrasulphophthalocyanine as photosensitiser, in K562 human leukaemic cells were investigated. Cell responses to individual and combined drug treatment under different experimental conditions revealed synergistic drug toxicity. The latter was evident from various events of cell response, including supra-additive accumulation of cells in G2/M cell cycle phase and endonucleolytic DNA fragmentation (apoptosis). The involvement of the cellular antioxidant system in the synergistic interactions of photosensitisation and VP-16 is proposed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Cell Cycle / drug effects
  • Cell Division / drug effects
  • Combined Modality Therapy
  • DNA, Neoplasm / drug effects
  • DNA, Neoplasm / metabolism
  • Drug Interactions
  • Etoposide / pharmacology*
  • Humans
  • Indoles / pharmacology*
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / drug therapy*
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / pathology
  • Nucleosomes / drug effects
  • Nucleosomes / metabolism
  • Organometallic Compounds / pharmacology*
  • Photochemotherapy / methods*
  • Photosensitizing Agents / pharmacology*
  • Tumor Cells, Cultured


  • Antineoplastic Agents, Phytogenic
  • DNA, Neoplasm
  • Indoles
  • Nucleosomes
  • Organometallic Compounds
  • Photosensitizing Agents
  • aluminum phthalocyanine
  • Etoposide