The Emerging Influences of Telomere and Telomerase in Inflammatory Bowel Disease and Cancer Progression

• The functional role and mechanism of telomerase and telomeres in inflammatory bowel disease are summarized. • It demonstrates the characteristics of telomere and telomerase in inflammatory bowel disease progression to colorectal cancer. • The significance and problems of targeted telomerase in the treatment of inflammatory bowel disease and its development of colon cancer are emphasized. Telomerase is a key enzyme that extends telomere length and thus maintains genomic stability. In inflammatory bowel disease (IBD) and colorectal cancer (CRC) to which it progresses, telomeres and telomerase have been found to be key factors. Notably, telomeres and telomerase play different roles in the progression of IBD and CRC. Short telomeres and low telomerase activity were found in IBD. In CRC, although telomere length is short, telomerase activity is enhanced. Therefore, in the transformation of IBD to CRC, the impact on telomeres and the functional mechanism of telomerase diverge significantly. Here we review the key roles of oxidative stress, genomic instability, gut microbiota and microenvironment in the relationship between IBD and telomere maintenance, and summarize the possible mechanisms of telomerase in promoting IBD-CRC transformation. We emphasize that changes in telomeres and telomerase were closely related to disease progression during the transformation of IBD to CRC, and the function of telomerase also changed at different stages of progression, thus suggesting that the diagnosis and treatment plan should be adopted at different stages of the disease. Further study of telomerase and its role in regulating telomeres in the progression of IBD and CRC is of great significance for targeted therapy and drug development.