Our broad goal is to develop effective, molecularly targeted therapies for improving survival rates and longterm quality of life in children with EwS. Toward that goal, we conducted a high throughput screen of a complex chemical library to identify new drugs to treat this disease. This effort resulted in identification ML111, which potently inhibits EwS cell viability in vitro, as well as that of subsets of hematopoietic and non-small cell lung cancers.