Caspase-dependent apoptosis induced by telomere cleavage and TRF2 loss


Multani A., Ozen M., Narayan S., Kumar V., Chandra J., McConkey D., ...Daha Fazla

NEOPLASIA, cilt.2, sa.4, ss.339-345, 2000 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 2 Sayı: 4
  • Basım Tarihi: 2000
  • Doi Numarası: 10.1038/sj.neo.7900105
  • Dergi Adı: NEOPLASIA
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.339-345
  • Anahtar Kelimeler: telomeric erosion, DNA fragmentation, caspase inhibitors, fluorescence in situ hybridization, telomeric-repeat binding factor (TRF), PROGRAMMED CELL-DEATH, CANCER DEVELOPMENT, DNA FRAGMENTATION, EPITHELIAL-CELLS, PROTEIN, LENGTH, BCL-2, ACTIVATION, END, CHROMOSOMES
  • Kocaeli Üniversitesi Adresli: Evet

Özet

Chromosomal abnormalities involving telomeric associations (TAs) often precede replicative senescence and abnormal chromosome configurations. We report here that telomere cleavage following exposure to pro-apoptotic agents is an early event in apoptosis, Exposure of human and murine cancer cells to a variety of pro-apoptotic stimuli (staurosporine, thapsigargin, anti-fas antibody, and cancer chemotherapeutic agents) resulted in telomere cleavage and aggregation, and finally their extrusion from the nuclei. Telomere loss was associated with arrest of cells in G(2)/M phase and preceded DNA fragmentation. Telomere erosion and subsequent large-scale chromatin cleavage were inhibited by overexpression of the anti-apoptotic protein, bcl-2, and two peptide caspase inhibitors (BACMK and zVADfmk), indicating that both events are regulated by caspase activation. The results demonstrate that telomere cleavage is an early chromatin alteration detected in various cancer cell lines leading to drug-induced apoptosis, and suggest that this event contributes to mitotic catastrophe and induction of cell death. Results also suggest that the decrease of telomeric-repeat binding factor 2 (TRF2) may be the earliest event in the ara-C-induced telomere shortening, induction of endoreduplication and chromosomal fragmentation leading to cell death.