Telomere length in the colon is related to colorectal adenoma prevalence.

Sarah D Peacock,Thomas E Massey,Will D King,Stephen J Vanner,Arthur J Lustig

doi:10.1371/journal.pone.0205697

Abstract

Telomere length has been associated with risk of several cancers. However, studies of the relationship between telomere length and colorectal cancer risk have been inconsistent. This study examined the relationship between telomere length in normal colon tissue and the prevalence of colorectal adenoma, a precursor to colorectal cancer. This nested case-control study consisted of 85 patients aged 40 to 65 undergoing a screening colonoscopy: 40 cases with adenoma(s) detected at colonoscopy and 45 controls with normal colonoscopy. During the colonoscopy, two pinch biopsies of healthy, normal appearing mucosa were obtained from the descending colon. Relative telomere length (rTL) was quantified in DNA extracted from colon mucosa using quantitative real-time PCR. Logistic regression was used to assess the relationship between telomere length and adenoma prevalence and estimate odds ratios and 95% confidence intervals. rTL was significantly longer in colon tissue of individuals with adenomas compared to healthy individuals (p = 0.008). When rTL was categorized into quartiles according to the distribution of rTL among controls, individuals with the longest telomeres had increased odds of adenoma when compared to individuals with shortest telomeres (OR = 4.58, 95% CI: 1.19, 17.7). This study suggests that long telomeres in normal colon tissue are associated with increased colorectal cancer risk.

Highlights

Telomeres play an important role in maintaining chromosomal stability and genetic integrity [1,2]
This study examined the relationship between telomere length in normal colonic mucosa and the prevalence of colorectal adenoma
This nested case-control study assessed the relationship between colon tissue Relative telomere length (rTL) and the prevalence of colorectal adenomas

Summary

Introduction

Telomeres play an important role in maintaining chromosomal stability and genetic integrity [1,2]. Telomere length and colorectal adenomas collection and analyses, decision to publish, or preparation of the manuscript Both short and long telomeres have been implicated in carcinogenesis. Telomere length limits uncontrolled cellular proliferation; normally, tumour suppressor mechanisms ensure that once telomeres reach a critical length, apoptosis or cellular senescence is triggered [20] This process prevents genetic instability [2] and the accumulation of mutations [21]. Colorectal tumourigenesis involves a dysplastic progression from aberrant epithelium to adenomatous polyp (adenoma) to colorectal cancer (adenocarcinoma) [54,55] This multi-step process is characterised by increasing chromosomal and genetic instability. The role of telomere length in colorectal carcinogenesis warrants further examination as results from studies of the association between telomere length and colorectal cancer risk remain equivocal. This study examined the relationship between telomere length in normal colonic mucosa and the prevalence of colorectal adenoma

Materials and methods

Results

Discussion