Telomere Length and Telomerase Activity in Subcutaneous and Visceral Adipose Tissues from Obese and Non-Obese Patients with and without Colorectal Cancer

Abstract

To investigate the molecular mechanisms that link obesity and colorectal cancer (CRC), we analyzed parameters related to telomere function in subcutaneous and visceral adipose tissues (SAT and VAT), including subjects with and without CRC, who were classified according to their body mass index (BMI). Adipose tissues were obtained from 147 patients who had undergone surgery. A total of 66 cases corresponded to CRC patients, and 81 subjects were not affected by cancer. Relative telomere length was established by qPCR, and telomerase activity was determined by a method based on the telomeric repeat amplification protocol. Our results indicated longer telomeres in patients affected by CRC, both in SAT and VAT, when compared to the group of subjects without CRC. Tumor local invasion was associated with telomere length (TL) in SAT. Considering the BMI values, significant differences were found in the TL of both adipose tissues between subjects affected by CRC and those without cancer. Overweight subjects showed the greatest differences, with longer telomeres in the group of CRC patients, and a higher number of cases with telomerase reactivation in the VAT of subjects without cancer. In conclusion, parameters related to telomere function in adipose tissue could be considered as potential biomarkers in the evaluation of CRC and obesity.

Telomere Length as a New Risk Marker of Early-Onset Colorectal Cancer

“…Among the cellular factors that correlate with aging, one of the most remarkable is TL. Thus, TL has been established as a useful and easily measurable marker by RT-qPCR [ 9 , 10 , 11 , 12 ], although there are other approaches for its quantification, such as terminal restriction fragment (TRF) length measurement by Southern blot [ 13 , 14 ]. In this regard, a study on germline telomere shortening by Lisa Boardman et al showed that longer telomeres increased the risk of developing EOCRC, whereas shorter telomeres were associated with late-onset CRC [ 15 ].…”