Damaging Tumor Vessels with an Ultrasound-Triggered NO Release Nanosystem to Enhance Drug Accumulation and T Cells Infiltration

Abstract

Yan Xu, Jiwei Liu, Zhangya Liu, Guoguang Chen, Xueming Li, Hao Ren School of Pharmaceutical Science, Nanjing Tech University, Nanjing, Jiangsu, People’s Republic of ChinaCorrespondence: Xueming Li; Hao RenNanjing Tech University, School of Pharmaceutical Science and Pharmaceutical Engineering, No. 30 Puzhu South Road, Nanjing, 211816, ChinaEmail [email protected]; [email protected]: Limited by tumor vascular barriers, restricted intratumoural T cell infiltration and nanoparticles accumulation remain major bottlenecks for anticancer therapy. Platelets are now known to maintain tumor vascular integrity. Therefore, inhibition of tumor-associated platelets may be an effective method to increase T cell infiltration and drug accumulation at tumor sites. Herein, we designed an ultrasound-responsive nitric oxide (NO) release nanosystem, SNO-HSA-PTX, which can release NO in response to ultrasound (US) irradiation, thereby inhibiting platelet function and opening the tumor vascular barrier, promoting drug accumulation and T cell infiltration.Methods: We evaluated the ability of SNO-HSA-PTX to release NO in response to US irradiation. We also tested the effect of SNO-HSA-PTX on platelet function. Plenty of studies including cytotoxicity, pharmacokinetics study, biodistribution, blood perfusion, T cell infiltration, in vivo antitumor efficacy and safety assessment were conducted to investigate the antitumor effect of SNO-HSA-PTX.Results: SNO-HSA-PTX with US irradiation inhibited tumor-associated platelets activation and induced openings in the tumor vascular barriers, which promoted the accumulation of SNO-HSA-PTX nanoparticles to the tumor sites. Meanwhile, the damaged vascular barriers allowed oxygen-carrying hemoglobin to infiltrate tumor regions, alleviating hypoxia of the tumor microenvironment. In addition, the intratumoral T cell infiltration was augmented, together with chemotherapy and NO therapy, which greatly inhibited tumor growth.Discussion: Our research designed a simple strategy to open the vascular barrier by inhibiting the tumor-associated platelets, which provide new ideas for anti-tumor treatment.Keywords: intratumoural T cell infiltration, nanoparticles accumulation, tumor vascular barriers, nitric oxide, tumor-associated platelets

Keywords

• intratumoural t cell infiltration
• nanoparticles accumulation
• tumor vascular barriers
• nitric oxide
• tumor-associated platelets