CTC1 increases the radioresistance of human melanoma cells by inhibiting telomere shortening and apoptosis

Luo,Y. M.; Xia,N. X.; Yang,L.; Li,Z.; Yang,H.; Yu,H. J.; Liu,Y.; Lei,H.; Zhou,F.  X.; Xie,C. H.; Zhou,Y.  F.

doi:10.3892/ijmm.2014.1721

CTC1 increases the radioresistance of human melanoma cells by inhibiting telomere shortening and apoptosis

Authors:
- Y. M. Luo
- N. X. Xia
- L. Yang
- Z. Li
- H. Yang
- H. J. Yu
- Y. Liu
- H. Lei
- F. X. Zhou
- C. H. Xie
- Y. F. Zhou
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Affiliations: Hubei Cancer Clinical Study Center, Hubei Key Laboratory of Tumor Biological Behaviors, Wuhan University, Wuhan, Hubei, P.R. China, Department of Radiation Oncology and Medical Oncology, Zhongnan Hospital, Wuhan University, Wuhan, Hubei, P.R. China
Published online on: April 2, 2014 https://doi.org/10.3892/ijmm.2014.1721
Pages: 1484-1490
Copyright: © Luo et al. This is an open access article distributed under the terms of Creative Commons Attribution License [CC BY_NC 3.0].

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Abstract

Melanoma has traditionally been viewed as a radioresistant cancer. However, recent studies suggest that under certain clinical circumstances, radiotherapy may play a significant role in the treatment of melanoma. Previous studies have demonstrated that telomere length is a hallmark of radiosensitivity. The newly discovered mammalian CTC1‑STN1-TEN1 (CST) complex has been demonstrated to be an important telomere maintenance factor. In this study, by establishing a radiosensitive/radioresistant human melanoma cell model, MDA-MB-435/MDA-MB‑435R, we aimed to investigate the association of CTC1 expression with radiosensitivity in human melanoma cell lines, and to elucidate the possible underlying mechanisms. We found that CTC1 mRNA and protein levels were markedly increased in the MDA-MB‑435R cells compared with the MDA-MB‑435 cells. Moreover, the downregulation of CTC1 enhanced radiosensitivity, induced DNA damage and promoted telomere shortening and apoptosis in both cell lines. Taken together, our findings suggest that CTC1 increases the radioresistance of human melanoma cells by inhibiting telomere shortening and apoptosis. Thus, CTC1 may be an attractive target gene for the treatment of human melanoma.

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