High mobility group（HMG） protein is a non -histone protein that is widely present in eukaryotes chromatin. HMG wins its name because of its small molecular weight and rapid migration in polyacrylamide gel electrophoresis. DNA damage originated from both ultra violet light and ionizing irradiation. High mobility group N （HMGN） protein is an emerging factor that is important for chromatin alterations in response to DNA damage. DNA lesions threaten the integrity of the genome and are a major factor in cancer formation and progression. The role of HMGN in anti-tumor will be discussed.
