Impact of chemotherapy on telomere length in sporadic and familial breast cancer patients

Abstract

Purpose-Recently, we observed that telomeres of BRCA1/2 mutation carriers were shorter than those of controls or sporadic breast cancer patients, suggesting that mutations in these genes might be responsible for this event. Given the contradictory results reported in the literature, we tested whether other parameters, such as chemotherapy, could be modifying telomere-length.Methods-We performed a cross-sectional study measuring leukocyte telomere-length of 266 sporadic breasts cancer patients treated with first-line chemotherapy, with a median follow up of 240 days.Additionally, we performed both cross-sectional and longitudinal studies in a series of 236 familial breast cancer patients that included affected and non-affected BRCA1/2 mutation carriers. We Ethical standards:The authors declare that this work complies with current Spanish laws. Conflict of interest:The authors declare that they have no conflicts of interest. Europe PMC Funders Group Europe PMC Funders Author ManuscriptsEurope PMC Funders Author Manuscripts have measured in leukocytes from peripheral blood: The telomere-length, percentage of short telomeres (<3Kb), telomerase activity levels and the annual telomere shortening speed.Results-In sporadic cases we found that chemotherapy exerts a transient telomere shortening effect (around 2 years) that varies depending on the drug combination.In familial cases, only patients receiving treatment were associated with telomere shortening but they recovered normal telomere-length after a period of two years.Conclusion-Chemotherapy affects telomere-length and should be considered in the studies that correlate telomere-length with disease susceptibility.

Leucocyte telomere length, genetic variants at theTERTgene region and risk of pancreatic cancer

“…32 33 These inconsistencies may result from differences in study design and assay performance and the potential impact of confounding factors. 34 The kinetics of telomere loss appear to vary by timing of measurement before cancer diagnosis 35 and treatment after diagnosis, 36 impairing the ability to combine data from studies with different designs. In the current study, all blood samples were collected prospectively >2 years prior to diagnosis and before any cancer-directed treatments, limiting the impact of these factors on our results.…”

Effect of chemotherapy on the length of telomeres in patients with breast cancer suffering from arterial hypertension

“…Ранее описывалось уменьшение длины теломеров в процессе проведения ХТ у больных РМЖ [17], что, вероятно, связано с прямым повреждающим действием препаратов как на опухолевые, так и на гемопоэтические клетки [18]. Однако в некоторых работах не наблюдалось значимого изменения длины теломеров при ХТ [18].…”

Telomere Length Is Predictive of Breast Cancer Risk inBRCA2Mutation Carriers

“…This is indeed reflected in our study group where TL is shorter in breast cancer affected women than in unaffected women. Radiotherapy and chemotherapy have both been shown to affect leukocyte TL (38)(39)(40), yet most studies do not account for treatment as a confounding factor, most likely due to incomplete information. Prospective studies with samples taken before diagnosis have, contrary to retrospective studies, generally shown no significant difference in TL between cases and controls (27,41).…”