The relationship between microRNAs and colorectal cancer radiosensitivity and underlying mechanism

Colorectal cancer is currently the third most common cancer worldwide, and there are still half of the patients undergoing recurrence and metastasis after surgical treatment, so it is necessary for colorectal cancer patients to receive radiation therapy routinely. Due to the side effects brought by radiotherapy, it is of great importance to solve how to minimize the radiation dose in radiation therapy and improve radiation sensitivity. In recent years, people discovered that microRNAs can not only be involved in the origins of colorectal cancer and progress, but also play a increasingly important role in cancer radiosensitivity. MicroRNAs can regulate tumor radiosensitivity by influencing tumor microenvironment and function on target genes. DNA damage response caused by radiation includes the activation of ATM, histone modification and chromatin remodeling, cell cycle arrest, damage repair and apoptosis. microRNAs can regulate tumor radiosensitivity through above processes. This review focuses on the mechanism of microRNAs in affecting DNA damage repair and prospects the future of microRNAs in influencing the sensitivity of cancer radiotherapy in clinical application. (authors)