Tumor vascular-targeted co-delivery of anti-angiogenesis and chemotherapeutic agents by mesoporous silica nanoparticle-based drug delivery system for synergetic therapy of tumor.

To overcome the drawback of drug non-selectivity in traditional chemotherapy, the construction of multifunctional targeting drug delivery systems is one of the most effective and prevailing approaches. The intratumoral anti-angiogenesis and the tumor cell-killing are two basic approaches in fighting tumors. Herein we report a novel tumor vascular-targeting multidrug delivery system using mesoporous silica nanoparticles as carrier to co-load an antiangiogenic agent (combretastatin A4) and a chemotherapeutic drug (doxorubicin) and conjugate with targeting molecules (iRGD peptide) for combined anti-angiogenesis and chemotherapy. Such a dual-loaded drug delivery system is capable of delivering the two agents at tumor vasculature and then within tumors through a differentiated drug release strategy, which consequently results in greatly improved antitumor efficacy at a very low doxorubicin dose of 1.5 mg/kg. The fast release of the antiangiogenic agent at tumor vasculatures led to the disruption of vascular structure and had a synergetic effect with the chemotherapeutic drug slowly released in the following delivery of chemotherapeutic drug into tumors.