**Author details**

Alejandro D. Bolzán\*

Address all correspondence to: abolzan@imbice.gov.ar; adbolzan64@gmail.com

Laboratorio de Citogenética y Mutagénesis, Instituto Multidisciplinario de Biología Celular (IMBICE, CCT-CONICET La Plata – CICPBA-UNLP), La Plata, Argentina

### **References**

**4.** Some drugs (i.e., 5-azacytidine and trichostatin A) could exert its anticancer effect by inducing telomere lengthening instead of shorthening or erosion. Telomere elongation induced by these drugs may have the effect of stabilizing the telomere thus reducing the amount of genetic damage the cell will undergo, thereby stopping the clonal evolution of the cancer cell population. As a result, these tumors may be more susceptible to further treatment. Alternatively, the elongation of telomeres in cancer cells may give rise to

**5.** Some anticancer drugs -like paclitaxel- could exert their anticancer effect by inducing telomere fusions. Thus, this drug could be used to enhance chemosensitivity in cells with

**6.** Finally, regardless of the underlying mechanism involved in the long-term telomere instability induced by some anticancer drugs, the data available raise concern about the potential risks of a long-term chemotherapy based on these drugs. Damage to telomeres induced by cytostatic therapy theoretically could generate telomere shortening and, subsequently, induce an additional genomic instability in neoplastic cells, this effect causing undesirable side effects, including secondary malignancies in long-term survivors

In summary, further studies will be needed to fully elucidate the effects of anticancer drugs on telomere stability. Depending on the drug, these studies should be aimed at determining whether it induces short- and long-term telomere instability or not, and if this telomere instability is due to chromosome breakage or telomere dysfunction. Undoubtedly, these studies will contribute to a better understanding of the effects of the anticancer drugs on mammalian telomeres. This information will be of great importance to understand the genomic

The author acknowledges the financial support of the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET, grant PIP No. 0182), Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CICPBA), and University of La Plata (UNLP) from Argentina.

Laboratorio de Citogenética y Mutagénesis, Instituto Multidisciplinario de Biología Celular

Address all correspondence to: abolzan@imbice.gov.ar; adbolzan64@gmail.com

(IMBICE, CCT-CONICET La Plata – CICPBA-UNLP), La Plata, Argentina

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132 Telomere - A Complex End of a Chromosome

dysfunctional telomeres.

instability associated with chemotherapy regimens.

of cancer.

**Acknowledgements**

**Author details**

Alejandro D. Bolzán\*


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