Bisphosphonates decrease telomerase activity and hTERT expression in MCF-7 breast cancer cells.

Luca Dalle Carbonare; Maria Teresa Valenti; Giuseppe Azzarello; Elena Balducci; Gaetano Crepaldi; Giuseppe Realdi; Orazio Vinante; Sandro Giannini

doi:10.1016/j.mce.2005.03.018

PubMed · 15978718

Bisphosphonates decrease telomerase activity and hTERT expression in MCF-7 breast cancer cells.

Luca Dalle Carbonare·Maria Teresa Valenti·Giuseppe Azzarello·Elena Balducci·Gaetano Crepaldi·Giuseppe Realdi·Orazio Vinante·Sandro Giannini

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Abstract

Bisphosphonates are important in the management of tumours with secondary bone involvement. Recent findings have suggested that these drugs also have an effect on primary tumour burden. Telomerase is a cellular ribonucleoprotein reverse transcriptase responsible for elongation of the telomere. Telomerase expression is increased in many cancers. We studied the direct effects of clodronate, alendronate, and pamidronate (from 10(-6) to 10(-4) M) on MCF-7 human breast cancer cell line. In particular, we investigated their effect on viability, proliferation, apoptosis, human telomerase reverse transcriptase expression (h-TERT) by RT-PCR and telomerase activity. Alendronate and pamidronate showed an inhibition of viability (-63 and -35%, respectively; p < 0.0001) and proliferation of cancer cells, while no effect was observed with clodronate. Amino-bisphosphonates induced a significant increase of apoptosis in MCF-7. In addition, they showed a significant decrease in telomerase expression and activity with respect to control and to clodronate.

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Alendronate Antineoplastic Agents Apoptosis Breast Neoplasms Cell Proliferation Clodronic Acid DNA-Binding Proteins Diphosphonates Female Gene Expression Humans Pamidronate Telomerase Tumor Cells, Cultured Journal Article

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Luca Dalle Carbonare, Maria Teresa Valenti, Giuseppe Azzarello, Elena Balducci, Gaetano Crepaldi, Giuseppe Realdi, Orazio Vinante, Sandro Giannini. 2005-08-30. Bisphosphonates decrease telomerase activity and hTERT expression in MCF-7 breast cancer cells.. https://doi.org/10.1016/j.mce.2005.03.018

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