Targeting Pancreatic Cancer with Novel Plumbagin Derivatives: Design, Synthesis, Molecular Mechanism, <i>In Vitro</i> and <i>In Vivo</i> Evaluation
Suresh Awale, Hayato Baba, Nguyễn Duy Phan, Min Jo Kim, Juthamart Maneenet, Koichi Sawaki, Mitsuro Kanda, Tomoyuki Okumura, Tsutomu Fujii, Takuya Okada, Takuya Okada, Takahiro Maruyama, Takahiro Okada, Takahiro Okada, Naoki Toyooka
Abstract
Pancreatic tumors grow in an “austerity” tumor microenvironment characterized by nutrient deprivation and hypoxia. This leads to the activation of adaptive pathways in pancreatic cancer cells, promoting tolerance to nutrition starvation and aggressive malignancy. Conventional anticancer drugs are often ineffective against tumors that grow in such austerity condition. Plumbagin, a plant-derived naphthoquinone, has shown potent preferential cytotoxicity against pancreatic cancer cells under nutrient-deprived conditions. Therefore, we synthesized a series of plumbagin derivatives and found that 2-(cyclohexylmethyl)-plumbagin ( 3f ) was the most promising compound with a PC 50 value of 0.11 μM. Mechanistically, 3f was found to inhibit the PI3K/Akt/mTOR signaling pathways, leading to cancer cell death under nutrient-deprived conditions. In vivo studies using pancreatic cancer xenograft mouse models confirmed the efficacy of 3f, demonstrating significant inhibition of tumor growth in a dose-dependent manner. Compound 3f represents a highly promising lead for anticancer drug development based on an antiausterity strategy.