Curcumin-induced apoptosis in human leukemia cell HL-60 is associated with inhibition of telomerase activity.
Mol Cell Biochem. 2007 Mar;297(1-2):31-9. Epub 2006 Nov 10. PMID: 17096185
Department of Environmental Carcinogenesis&Toxicology, Chittaranjan National Cancer Institute, 37, S.P. Mukherjee Road, Kolkata 700 026, India.
Curcumin (diferuloylmethane), a natural cancer chemopreventive compound, has been tested for its action in acute myeloblastic leukemia cell line HL-60. The results clearly show that curcumin induces apoptosis in these cells as evidenced by the release of cytochrome c from mitochondria to the cytosol and increase in the DNA content in sub G1 region as observed in FACS analysis. Apoptosis is apparently mediated by up-regulation of apoptotic gene bax and simultaneous down-regulation of anti-apoptotic gene bcl-2 followed by activation of caspases 3 and 8 and degradation of PARP. Telomerase, a reverse transcriptase, has been found to be activated in more than 80% of human cancers and, therefore, can be considered as a potential marker for tumorigenesis. Certain natural compounds have the potential of inhibiting telomerase activity leading to suppression of cell viability and induction of apoptosis. The present study shows that curcumin-induced apoptosis coincides with the inhibition of telomerase activity in a dose dependent manner.