Odoracin (25), along with odoratrin (45), gniditrin (20), 12-O-(E)-cinnamoyl-9,13,14-ortho-(2E,4E)-decadienylidyne-5β,12β-dihydroxyresiniferonol-6α,7α-oxide (41) and 12-O-(E)-cinnamoyl-9,13,14-ortho-(2E,4E,6E)-decatrienylidyne-5β,12β-dihydroxyresiniferonol-6α,7α-oxide (40), was found to have ornithine decarboxylase (ODC)-inducing activity in mouse skin, which correlated with a tumor-promoting effect; these compounds were simultaneously determined to be piscicidal [27]. This evidence concerns the gene ODC1 and neoplasm.