3T3 cell line A549 cell line Article Cucurbitaceae K ras protein MTT assay Raf protein STAT3 protein actin filament animal experiment animal model antineoplastic activity apoptosis bitter taste cell cycle G2 phase cell cycle M phase cell cycle arrest cucurbitacin cytotoxicity epidermal growth factor receptor genetic transcription lung cancer lung tumor mitogen activated protein kinase mouse nonhuman phosphatidylinositol 3 kinase protein kinase B signal transduction transgenic mouse