One of the most common diseases in the present era is cancer. The common treatment methods used to control cancer include surgery, chemotherapy, and radiotherapy. Despite progress in the treatment of cancers, there still is no definite therapeutic approach. Among the currently proposed strategies, immunotherapy is a new approach that can provide better outcomes compared with existing therapies. Employing natural killer (NK) cells is one of the means of immunotherapy. As innate lymphocytes, NK cells are capable of rapidly responding to cancer cells without being sensitized or restricted to the cognate antigen in advance, as compared to T cells that are tumor antigen‐specific. Latest insights into the biology of NK cells have clarified the underlying molecular mechanisms of NK cell maturation and differentiation, as well as controlling their effector functions through the investigation of the ligands and receptors engaged in recognizing cancer cells by NK cells. Elucidating the fact that NK cells recognize cancer cells could similarly show the mechanism through which cancer cells possibly avoid NK cell‐dependent immune surveillance. Additionally, the expectations for novel immunotherapies by targeting NK cells have increased through the latest clinical outcomes of T–cell‐targeted cancer immunotherapy. For this emerging method, researchers are still attempting to develop protocols for conferring the best proliferation and expansion medium, activation pathways, utilization dosage, transferring methods, as well as reducing possible side effects in cancer therapy. This study reviews the NK cells, their proliferation and expansion methods, and their recent applications in cancer immunotherapy.

中文翻译：

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基于自然杀伤细胞的癌症免疫治疗的当前进展。

当今时代最常见的疾病之一是癌症。用于控制癌症的常见治疗方法包括手术、化学疗法和放射疗法。尽管癌症的治疗取得了进展，但仍然没有明确的治疗方法。在目前提出的策略中，免疫疗法是一种新方法，与现有疗法相比，可以提供更好的结果。使用自然杀伤 (NK) 细胞是免疫治疗的手段之一。作为先天淋巴细胞，与具有肿瘤抗原特异性的 T 细胞相比，NK 细胞能够快速响应癌细胞，而无需预先对同源抗原敏感或受限。对 NK 细胞生物学的最新见解阐明了 NK 细胞成熟和分化的潜在分子机制，以及通过研究 NK 细胞识别癌细胞的配体和受体来控制它们的效应子功能。阐明 NK 细胞识别癌细胞的事实可以类似地显示癌细胞可能避免依赖 NK 细胞的免疫监视的机制。此外，通过 T 细胞靶向癌症免疫疗法的最新临床结果，人们对靶向 NK 细胞的新型免疫疗法的期望也有所增加。对于这种新兴方法，研究人员仍在尝试制定方案，以提供最佳增殖和扩增介质、激活途径、利用剂量、转移方法以及减少癌症治疗中可能出现的副作用。本研究回顾了 NK 细胞及其增殖和扩增方法，