PTOP and TRF1 help enhance the radio resistance in breast cancer cell

Cancer Cell International

Yunfeng Zhou¹  Conghua X¹  Fuxiang Zhou¹  Haijun Yu¹  Lei Yang¹  Nengxing Xia¹  Xiaoxi Yang¹  Zheng Li¹ 

[1] Department of Radiation and Medical Oncology, Zhongnan Hospital, Wuhan University, Donghu road 168, 430071, Wuhan City, Hubei Province, China

关键词: Radio resistant;    Telomere;    Telomere bonding protein;    TRF1;    PTOP;   

Others  :  792419
DOI  :  10.1186/1475-2867-14-7

 received in 2013-10-19, accepted in 2014-01-22,  发布年份 2014

【 摘 要 】

Purpose

The telomere binding proteins play an important role in telomere function, which contribute greatly to the radio resistant in human cancers. This research is designed to investigate the relationship among the telomere length, telomerase activity and changes of telomere binding protein PTOP and TRF1 in radio resistant breast cancer cell lines.

Methods

Irradiate MDA-MB-435 s breast cancer cell with total dose of 60 Gy delivered in 2 Gy/fraction and 6 Gy/fraction respectively, then measuring their telomere length by Southern blot analysis,telomerase activity by Telomerase PCR Elisa and detecting the expression of PTOP and TRF1 in both gene and protein levels. To further investigate the function of PTOP, using lentivirus technic to silence the PTOP gene and the detected the new silenced cells by southern blot and telomerase activity.

Results

2 radio resistant breast cancer cell lines were successfully established. The MDA-MB-435 s R60/6 was (approximate 8.1-8.6 kbp) about 2–2.4 folds to the patent cell (3.6-4.2 kbp), the MDA-MB-435 s R60/2 cell (approximate 5.3-6.3 kbp) was about 1.3-1.75 fold to the parent cell line. The telomerase activity was more enhanced in radio resistant cell lines than the parent cell. The expression of PTOP and TRF1 were significant increased in radio resistant cell lines than the patent cell in both gene and protein level. Otherwise, after using lentivirus technic to silence the PTOP gene, we found the radio resistant cell lines were significant decrease their radio resistances and telomerase activities.

Conclusion

The telomere binding protein PTOP and TRF1 were increased expressed in radio resistant breast cancer cell, PTOP was observed instinct positive correlated with telomere lengthen and telomerase activity enhancement.

【 授权许可】

   
2014 LI et al.; licensee BioMed Central Ltd.

【 图 表 】

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