Chemotherapy is the most commonly used treatment for cancer. However, due to their short circulation time and lack of specific biological distribution, chemotherapeutic drugs cause severe systemic toxicity. Using the agents specifically binding to the targeted molecules might resolve this dilemma. Aptamers can directly connect with the drugs or couple with the nano-carrier to reduce systemic toxicity. In this review, we elucidated the definition, characteristics and screening process of aptamers. The methods of drug delivery by aptamers were illustrated in details. Furthermore, clinical application of aptamers in recent years was briefly summarized and its long-term prospects were put forward.

中文翻译：

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适体筛选和药物递送方面的进展。

化学疗法是最常用的癌症治疗方法。然而，由于其循环时间短和缺乏特定的生物学分布，化学治疗药物引起严重的全身毒性。使用与目标分子特异性结合的试剂可以解决这个难题。适体可以直接与药物连接或与纳米载体偶联以降低全身毒性。在这篇综述中，我们阐明了适体的定义，特征和筛选过程。详细说明了适体的药物递送方法。此外，简述了近年来适体的临床应用，并提出了长期的前景。