Triptolide (TPL) is a small molecule isolated from a traditional Chinese herb Tripterygium wilfordii Hook F and shows excellent anticancer effect for pancreatic cancer cells. However, the poor water solubility and severe liver toxicity of TPL hindered its clinical application. In this study, TPL was covalently conjugated to a polymer and entrapped inside the core of the TPL nanogel (nTPL) to protect it from premature leakage during blood circulation. With the help of lactobionic acid (LBA), nTPL-LBA could selectively target the tumors in an orthotopic pancreatic cancer mouse model. TPL could be subsequently released intracellularly in its original form due to the presence of elevated intracellular esterase and GSH, and eventually kills cancer cells. nTPL-LBA treatment reduced tumor burden by 99% while not introducing TPL associated liver and kidney toxicities. Most importantly, more than half of the nTPL-LBA treated animals were tumor-free, suggesting that nTPL-LBA is an effective approach in eradicating pancreatic cancer.
Keywords: Triptolide; esterase-activatable; intracellular release; nano-prodrug; pancreatic cancer.