Nanocarriers are nanostructured vehicles employed to deliver anticancer drugs to the targeted tumor sites in the body. Nanocarriers have been successfully employed to circumvent certain limitations of conventional anticancer drug delivery while providing greater bioavailability, prolonged circulation time and higher tumor accumulation for enhanced therapeutic outcomes in cancer treatment. Nanocarriers are also responsive to functionalization to tailor their pharmaco-kinetics and achieve enhanced therapeutic outcomes in cancer therapy. Among organic, inorganic and hybrid type, several nanocarriers have gained approval for use in cancer patients, while many more are under clinical development. For the last two decades, cancer immunotherapy-based advanced targeting approaches such as monoclonal antibodies, antibody drug conjugates and immune checkpoint inhibitors that utilize human immune system functions have vastly developed which furnish better treatment options in several intractable cancers compared with traditional cancer therapies. This review discusses the imperative role of tumor vasculature in passive and active targeting of anticancer drugs using organic and inorganic nanocarriers and the current research efforts underway. The advanced targeting approaches for treatment of various cancers and their most recent clinical development scenario have been comprehensively explored. Further, potential challenges associated with each type of nanocarrier, and their translational obstacles are addressed.

中文翻译：

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用于抗癌药物靶向的纳米载体：最近的趋势和挑战。

纳米载体是一种纳米结构的载体，用于将抗癌药物输送到体内的靶向肿瘤部位。纳米载体已成功地用于规避传统抗癌药物递送的某些限制，同时提供更高的生物利用度、更长的循环时间和更高的肿瘤积累，以提高癌症治疗的治疗效果。纳米载体还对功能化做出反应，以定制其药代动力学并在癌症治疗中实现更好的治疗效果。在有机、无机和混合类型中，几种纳米载体已获得批准用于癌症患者，还有更多正在临床开发中。在过去的二十年里，基于癌症免疫疗法的先进靶向方法，如单克隆抗体、利用人类免疫系统功能的抗体药物偶联物和免疫检查点抑制剂得到了极大的发展，与传统的癌症疗法相比，它们为几种顽固性癌症提供了更好的治疗选择。本综述讨论了肿瘤血管系统在使用有机和无机纳米载体被动和主动靶向抗癌药物中的重要作用以及当前正在进行的研究工作。已经全面探索了治疗各种癌症的先进靶向方法及其最新的临床开发方案。此外，解决了与每种类型的纳米载体相关的潜在挑战及其转化障碍。