Department of Dermatology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100042, China.
Department of Dermatology and Venereology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100730, China.
Environ Sci Pollut Res Int. 2018 Jul;25(21):20569-20574. doi: 10.1007/s11356-018-2426-z. Epub 2018 Jun 12.
Photodynamic therapy (PDT) is widely used in dermatology to treat precancerous skin lesions and superficial non-melanoma skin cancers (NMSCs), including premalignant actinic keratosis, cutaneous squamous cell carcinoma in situ, and superficial basal cell carcinoma. The long-term cure rates of PDT range from 70 to 90% in NMSC patients, with excellent cosmetic results and good tolerance. However, the mechanism of action of PDT on tumors is complex. PDT not only kills tumor cells directly but also rapidly recruits immune cells to release inflammatory mediators to activate antitumor immunity. PDT-induced tumor death, also called immunogenic cell death, can trigger both innate and adaptive immune response, further enhancing the antitumor effect. For instance, inoculation of tumor cells killed via PDT to animals triggered a stronger antitumor immunity in vivo than tumor cell lysates produced by other treatments. More importantly, many immunotherapy regimens based on the immune effect of PDT have been developed and demonstrated to be a promising therapeutic method for cancer in pre-clinical trials. Therefore, increasing efforts have been undertaken to investigate the immune responses associated with PDT. In the present review, we first introduce the antitumor effect and the associated mechanisms of PDT in cancers. Then, we summarize studies on the immune responses induced by PDT in NMSCs. We also discuss the potential mechanisms underlying the process.
光动力疗法（PDT）在皮肤科中被广泛用于治疗癌前皮肤病变和浅表非黑色素瘤皮肤癌（NMSC），包括光化性角化病、原位皮肤鳞状细胞癌和浅表基底细胞癌。PDT 治疗 NMSC 患者的长期治愈率为 70%至 90%，具有极佳的美容效果和良好的耐受性。然而，PDT 对肿瘤的作用机制较为复杂。PDT 不仅能直接杀死肿瘤细胞，还能迅速招募免疫细胞释放炎症介质，激活抗肿瘤免疫。PDT 诱导的肿瘤死亡，也称为免疫原性细胞死亡，可触发先天和适应性免疫反应，进一步增强抗肿瘤作用。例如，将 PDT 杀伤的肿瘤细胞接种到动物体内，可引发比其他治疗方法产生的肿瘤细胞裂解物更强的抗肿瘤免疫力。更重要的是，许多基于 PDT 免疫效应的免疫治疗方案已被开发并在临床前试验中证明是一种有前途的癌症治疗方法。因此，人们已经投入更多的努力来研究与 PDT 相关的免疫反应。在本综述中，我们首先介绍了 PDT 在癌症中的抗肿瘤作用及其相关机制。然后，我们总结了 PDT 诱导 NMSC 免疫反应的研究。我们还讨论了该过程的潜在机制。
