An abnormal tumor growth induces solid stress in tumors, thus reducing blood perfusion. As a result, the impaired blood perfusion, with dense interstitial matrix in tumors significantly reduces the penetration and efficacy of nanotherapeutics. In this study, we have developed a losartan-loaded polydopamine nanoparticle (PLST) for the enhanced delivery of nanoparticles to tumors and improved photothermal cancer therapy. Losartan, an angiotensin inhibitor, is also able to alleviate the solid stress in tumors. It was laden on polydopamine nanoparticles via π-π stacking and was released upon tumor extracellular acidity. PLST reduced collagen production in vitro along with the lowered expression of profibrotic factors of TGF-β1, CCN2, and TIMP-1. The in vivo studies reveal that PLST reduced solid stress in tumors, and the amount of PLST accumulated in tumors was enhanced. The efficiency of the photothermal ablation of tumors was significantly enhanced by using PLST.

中文翻译：

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载有血管紧张素拮抗剂的黑色素样纳米颗粒，用于改善的光热癌症治疗。

异常的肿瘤生长会在肿瘤中诱发固体压力，从而减少血液灌注。结果，在肿瘤中具有密集的间质基质的受损的血液灌注显着降低了纳米治疗剂的渗透和功效。在这项研究中，我们开发了一种氯沙坦负载的聚多巴胺纳米颗粒（PLST），用于增强纳米颗粒向肿瘤的递送和改善的光热癌症治疗。血管紧张素抑制剂洛沙坦也能够减轻肿瘤中的固体压力。它通过π-π堆积负载在聚多巴胺纳米颗粒上，并在肿瘤细胞外酸度释放。PLST降低了体外胶原蛋白的产生，同时降低了TGF-β1，CCN2和TIMP-1的纤维化因子表达。体内研究表明PLST可以减轻肿瘤中的固体压力，并增加了肿瘤中PLST的积累量。使用PLST显着提高了肿瘤的光热消融效率。