Lysine-specific demethylase 1 (LSD1/KDM1A/AOF2/BHC110) is expressed and is an epigenetic drug target in chondrosarcoma, Ewing's sarcoma, osteosarcoma, and rhabdomyosarcoma. Lysine-specific demethylase 1 (GeneID 23028), a flavin-dependent monoamine oxidoreductase and a histone demethylase, serves as an epigenetic coregulator of transcription. Lysine-specific demethylase 1 is up-regulated in neuroblastoma and in bladder, breast, colorectal, gastric, lung, and neuroendocrine cancers, and its overexpression drives the cell cycle of otherwise nontransformed human cells, suggesting oncogenic properties. Lysine-specific demethylase 1 was recently reported to be also overexpressed in several different mesenchymal tumors. We investigated lysine-specific demethylase 1 expression in over 500 sarcomas by gene expression profiling and tissue microarray-coupled immunohistochemical analyses and confirmed lysine-specific demethylase 1 overexpression in rhabdomyosarcoma and synovial sarcoma. We also show for the first time that lysine-specific demethylase 1 is also overexpressed in chondrosarcoma, Ewing's sarcoma, and osteosarcoma wherein it localizes in cell nuclei. We further show that a US Food and Drug Administration-approved drug that inhibits lysine-specific demethylase 1 also inhibits chondrosarcoma, Ewing's sarcoma, osteosarcoma, and rhabdomyosarcoma cell growth in vitro. These data suggest that lysine-specific demethylase 1 plays a role in sarcoma pathology and that lysine-specific demethylase 1 inhibition strategies might represent a novel means to inhibiting growth of lysine-specific demethylase 1-overexpressing sarcomas.Copyright © 2012 Elsevier Inc. All rights reserved.