PROBLEM TO BE SOLVED: To provide an anticancer agent for preventing and/or treating cancers, more specifically, an epithelial cancer and a hematological cancer.SOLUTION: An anticancer agent comprises Simalikalactone E (SkE) represented by the formula in the figure as an active ingredient. Simalikalactone E is used for preventing and/or treating cancer in which the Ras/Raf/MEK/Erk signaling pathway is activated. Simalikalactone E is represented by the formula (:1 SkE) in the figure.SELECTED DRAWING: Figure 1【課題】がん、より詳細には、上皮性がんおよび血液がんを予防及び/又は治療する抗がん剤の提供。【解決手段】下式で表わされるシマリカラクトンE(SkE)を有効成分とする抗がん剤。Ras/Raf/MEK/Erkシグナル伝達経路が活性化されるがんを予防又は治療するためのシマカラクトンE。下記式(:1 SkE)で表わされるシマカラクトンE。【選択図】図1