In most of the mice in which we implanted sema3E or sema3D expressing U87MG or U373MG cells we could not detect any tumors at all even after more than 60 days and most of the mice that did not survive in the groups that were grafted with the semaphorin expressing tumor cells died of unknown reasons rather than because of brain tumors. This evidence concerns the gene SEMA3D and neoplasm.