Growing evidence from these past years shows that LSD1 and LSD2 are key proteins in enabling cancer cells to achieve cancer hallmarks such as genome instability, sustaining proliferative signals or activating invasion and metastasis, not only in cancers of the gastrointestinal system, but also in cancers such as prostate cancer, neuroblastoma, lung cancer and acute myeloid leukaemia [67]. This evidence concerns the gene KDM1A and lung cancer.