Cancer and chronic tissue injury: Abnormal repair tissue or functional repair tissue?

摘要

Cancer is increasingly being viewed as a stem cell disease. But stem cell activity is tightly con-trolled, raising the question of how normal regula-tion might be subverted in carcinogenesis. The long-known association between cancer and chronic tissue injury, and the more recently appreciated roles of Hedgehog and Wnt signalling pathways in tissue regeneration, stem cell renew-al and cancer growth together indicate that carci-nogenesis is the response of chronic tissue injury . The charming question is whether tumor tis-sue is an abnormal repair tissue or a functional re-pair tissue.