Cerebral delivery of redox-responsive lenalidomide prodrug plus methotrexate for primary central nerve system...

Primary central nervous system lymphoma (PCNSL) is an extremely malignant CNS tumor with high incidence and mortality rates. Its chemotherapy in the clinic has been restricted owing to unsatisfactory drug distribution in the cerebral tissues. In this study, a redox-responsive prodrug of disulfide-lenalidomide-methoxy polyethylene glycol (LND-DSDA-mPEG) was successfully developed for the cerebral delivery of lenalidomide (LND), and methotrexate (MTX) via subcutaneous (s.c.) administration at the neck for combined anti-angiogenesis and chemotherapy on PCNSL. Both the subcutaneous xenograft tumor model and orthotopic intracranial tumor model demonstrated that the co-delivery of LND and MTX nanoparticles (MTX@LND NPs) may significantly inhibit the growth of lymphoma and effectively prevent liver metastasis by downregulating CD31 and VEGF expression. Moreover, an orthotopic intracranial tumor model further verified that through s.c. administration at the neck, redox-responsive MTX@LND NPs could bypass the blood-brain barrier (BBB), efficiently distribute into brain tissues, and effectively inhibit lymphoma growth in the brain, as detected by magnetic resonance imaging (MRI). Taken together, this biodegradable, biocompatible, and redox-responsive nano-prodrug with highly effective targeted delivery of LND and MTX in the brain through the lymphatic vasculature may provide a facile and feasible treatment strategy for PCNSL in the clinic.