KEAP1 and neoplasm: Tumour cells lose the heterozygosity of gene through Nrf2 or Keap1 mutation so that Nrf2 and Keap1 cannot be combined normally resulting in Nrf2 accumulation in tumour cells and then activating downstream genes increasing the level of detoxifying enzymes in tumour cells, promoting the formation and growth of tumour cells, enhance the resistance of tumour cells to radiotherapy and chemotherapy.