You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is While advancing there is increased chance of developing cancers. Tumorigenesis in aging is due to: and explain in detail?
Telomerase is a ribonucleoprotein that is expressed in stem cells and most cancer cells, but not in somatic cells. More than 90% of human cancers express high levels of telomerase that prevent telomere shoening to critical levels and allow indefinite cell proliferation. Ref: Longo D.L. (2012). Chapter 84. Cancer Cell Biology and Angiogenesis. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds), Harrison's Principles of Internal Medicine, 18e.