Telomere length in peripheral blood leukocytes is associated with risk of colorectal cancer in Chinese population.
BACKGROUND
Human telomeres, tandem repeats of TTAGGG nucleotides at the ends of chromosomes, are essential for maintaining genomic integrity and stability. Results of previous epidemiologic studies about the association of telomere length with risk of colorectal cancer (CRC) have been conflicting.


METHODS
A case-control study was conducted in a Han population in Wuhan, central China. The relative telomere length (RTL) was measured in peripheral blood leukocytes (PBLs) using quantitative real-time polymerase chain reaction (PCR) in 628 CRC cases and 1,256 age and sex frequency matched cancer-free controls. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated using unconditional logistic regression models to evaluate the association between RTL and CRC risk.


RESULTS
Using median RTL in the controls as the cutoff, individuals with shorter RTL were associated with a significantly increased risk of CRC (adjusted OR = 1.27, 95%CI: 1.05-1.55). When participants were further categorized into 3 and 4 groups according to the tertile and quartile RTL values of controls, significant relationships were still observed between shorter RTL and increased CRC risk (OR per tertile = 1.13, 95%CI: 1.00-1.28, P(trend) = 0.045; OR per quartile = 1.12, 95%CI: 1.03-1.23, P(trend) = 0.012). In stratified analyses, significant association between shorter RTL and increased CRC risk was found in females, individuals younger than 60 years old, never smokers and never drinkers.


CONCLUSIONS
This study suggested that short telomere length in PBLs was significantly associated with an increased risk of CRC in Chinese Han population. Further validation in large prospective studies and investigation of the biologic mechanisms are warranted.
Department of Epidemiology and Biostatistics, and the Ministry of Education Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Qin
Q
Qin
The Chengdu Centers for Disease Control and Prevention, Chengdu, Sichuan, China.
Jingwen
J
Sun
Department of Epidemiology and Biostatistics, and the Ministry of Education Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Jieyun
J
Yin
Department of Epidemiology and Biostatistics, and the Ministry of Education Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Li
L
Liu
Department of Surgery, The Eighth Hospital of Wuhan, Wuhan, Hubei, China.
Jigui
J
Chen
Department of Surgery, The Eighth Hospital of Wuhan, Wuhan, Hubei, China.
Yuxing
Y
Zhang
Department of Epidemiology and Biostatistics, and the Ministry of Education Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Tingting
T
Li
Department of Epidemiology and Biostatistics, and the Ministry of Education Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Yun
Y
Shi
Department of Epidemiology and Biostatistics, and the Ministry of Education Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Sheng
S
Wei
Department of Epidemiology and Biostatistics, and the Ministry of Education Key Lab of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Shaofa
S
Nie
D000328:Adult; D044466:Asian People / Q000235:genetics*; D016022:Case-Control Studies; D003106:Colon / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011379:Prognosis; D012007:Rectum / Q000378:metabolism; D012307:Risk Factors; D016615:Telomere / Q000235:genetics*; D059505:Telomere Homeostasis / Q000235:genetics*