Leukocyte telomere attrition following radiotherapy in prostate cancer: a prospective study

Telomeres are protective protein-bound DNA repeat structures at the end of chromosomes, which play a critical role in maintaining chromosomal stability. With each somatic-cell division, telomeres progressively shorten, making telomere length a potential biomarker of biological aging. Ionizing radiation may accelerate telomere attrition, thereby promoting aging-related changes. In the present study, we analyzed the influence of radiotherapy on leucocyte telomere length in prostate cancer patients. A total of 314 patients treated with curative radiotherapy for prostate cancer were included in the present prospective study. Leukocyte relative telomere length (RTL) was measured by qPCR in peripheral blood samples collected before radiotherapy, at the end of radiotherapy, and at 3 and 15 months post-radiotherapy. Mean RTL values were 0.65 ± 0.34 at baseline, 0.62 ± 0.31 at the end of radiotherapy, 0.67 ± 0.43, and 0.55 ± 0.26 at the first and at the second follow-up, respectively. . Paired-Samples T-Test comparisons showed a significant reduction in RTL at 15 months post- radiotherapy compared to baseline (p < 0.001), end of radiotherapy (p = 0.001), and 3-month follow-up examination (p < 0.001). In our cohort, we observed a significant shortening of telomeres after radiotherapy indicating a potential contribution to accelerated cellular aging.