Nanoparticles can be used as drug carriers, contrast agents and radiosensitisers for the treatment of cancer. Nanoparticles can either passively accumulate within tumour sites, or be conjugated with targeting ligands to actively enable tumour deposition. With respect to passive accumulation, particles < 150 nm accumulate with higher efficiency within the tumour microenvironment, a consequence of the enhanced permeability and retention effect. Despite these favourable properties, clinical translation of nano-therapeutics is inhibited due to poor in vivo stability, biodistribution and target cell internalisation. Nano-therapeutics can be modified to exploit features of the tumour microenvironment such as elevated hypoxia, increased pH and a compromised extracellular matrix. This is in contrast to cytotoxic chemotherapies which generally do not exploit the characteristic pathological features of the tumour microenvironment, and as such are prone to debilitating systemic toxicities. This review examines strategies for tumour microenvironment targeting to improve nanoparticle delivery, with particular focus on the delivery of nucleic acids and gold nanoparticles. Evidence for key research areas and future technologies are presented and critically evaluated. Among the most promising technologies are the development of next-generation cell penetrating peptides and the incorporation of micro-environment responsive stealth molecules.

中文翻译：

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利用肿瘤响应制剂增强纳米颗粒的递送。

纳米粒子可用作药物载体，造影剂和放射增敏剂，用于治疗癌症。纳米颗粒可以被动地积聚在肿瘤部位内，或者与靶向配体结合以主动使肿瘤沉积。关于被动积累，＜150nm的颗粒在肿瘤微环境内以更高的效率积累，这是增强的渗透性和保留作用的结果。尽管具有这些有利特性，但由于体内稳定性，生物分布和靶细胞内在性较差，纳米治疗剂的临床翻译受到抑制。可以修改纳米疗法，以利用肿瘤微环境的特征，例如缺氧增加，pH升高和细胞外基质受损。这与通常不利用肿瘤微环境的特征性病理特征的细胞毒性化学疗法相反，因此倾向于使全身毒性减弱。这篇综述研究了靶向肿瘤微环境以改善纳米颗粒递送的策略，特别关注核酸和金纳米颗粒的递送。提出并严格评估了关键研究领域和未来技术的证据。最有前途的技术包括下一代细胞穿透肽的开发以及微环境响应性隐形分子的整合。这篇综述研究了靶向肿瘤微环境以改善纳米颗粒递送的策略，特别关注核酸和金纳米颗粒的递送。提出并严格评估了关键研究领域和未来技术的证据。最有前途的技术包括下一代细胞穿透肽的开发以及微环境响应性隐形分子的整合。这篇综述研究了靶向肿瘤微环境以改善纳米颗粒递送的策略，特别关注核酸和金纳米颗粒的递送。提出并严格评估了关键研究领域和未来技术的证据。最有前途的技术包括下一代细胞穿透肽的开发以及微环境响应性隐形分子的整合。