Imiquimod通过诱导integrinα1β1+组织型记忆性T细胞抑制宫颈癌复发的作用研究

Cervical cancer recurrence in situ is a common clinical issue which still lacks of good solution, the treatment is highly restricted due to poor reaction to palliative chemotherapy . Immunotherapy using the HPV antigens to stimulate adaptive immune mechanisms targeting cervical cancer cells has gotten important advances in recent years, otherwise few study has been focused on the prevention and treatment of cervical cancer recurrence in situ. In previous study, we used Toll like receptor 7 agonist Imiquimod as a local adjuvant administrated intra-vaginally, combined with therapeutic DNA vaccine, thus generated potent anti-tumor effect on an orthotopic mice cervical cancer model. This demonstrated imiquimod has potentials to shift tumor microenvironment by attracting tumor antigen specific CD8+T cells to genital tract, thereby significantly enhanced the anti-tumor effect. The study also indicated that imiquimod could induce cervical-vaginal tissue infiltrating T cells expressing tissue resident memory T cells (Trm) marker integrinα1β1. In the current proposal, we hypothesize that Imiquimod can inhibit the cervical cancer recurrence in situ by generating integrinα1β1+Trm. In this study, we are going to explore the mechanism of Imiquimod inducing integrinα1β1+Trm; test whether integrinα1β1+Trm play a crucial role in control recurrent cervical cancer; expose the downsream molecular signal pathway within integrinα1β1+ T cells through special techniques including pairing single cell suspension analyses with immunofluorescence imaging. This project will provide pre-clinical evidence for preventing and treating of cervical cancer recurrence in situ.

宫颈癌术后原位复发的病患治疗方案有限，是临床上亟待解决的难题。针对HPV抗原进行免疫治疗是近年来研究的热点，但将其用于控制宫颈癌原位复发尚无先例。本课题组的前期研究发现，Imiquimod作为局部佐剂协同抗肿瘤疫苗治疗小鼠原位宫颈癌，能够促进肿瘤内抗原特异性CD8+T细胞积聚，显著增强抗肿瘤效应。研究中还发现Imiquimod能够诱导生殖道局部浸润的T细胞表达组织型记忆T细胞（Trm）标志integrinα1β1。本课题据此假设：Imiquimod能够通过诱导integrinα1β1+Trm生成来抑制宫颈癌原位复发。在本课题中，我们将通过组织单细胞悬液流式分析结合影像学检查等技术，明确Imiquimod诱导integrinα1β1+Trm产生的机制；揭示integrinα1β1+Trm对宫颈癌复发模型的抑制作用及其分子信号通路，从而为解决宫颈癌原位复发的难题提供重要的临床前依据。

宫颈癌预防性疫苗的上市并不能治疗宫颈HPV持续性感染和宫颈癌，上述情况的免疫治疗仍是临床治疗中的热点问题；.本课题主要就以下三个方面的内容开展了研究：.1、.咪喹莫特乳膏局部应用治疗宫颈HPV持续性感染；.2、.咪喹莫特乳膏联合HPV16E7肽段主动免疫宫颈癌荷瘤小鼠的抗肿瘤效应；.3、.Ino80对于宫颈癌细胞增殖的调控；.4、.纳米材料与抗原/佐剂联合主动免疫治疗宫颈癌的的初步探索。.取得的重要结果及关键数据及其科学意义：.1、.咪喹莫特治疗组的HPV转阴率显著高于对照组（78.1% VS 31.4%，P=0.0002），咪喹莫特对于宫颈局部免疫微环境具有积极的调节作用，咪喹莫特治疗宫颈HPV持续性感染具备较高的临床推广价值。.2、.采用HPV16 E7合成多肽（氨基酸序列：GQAEPDRAHYNIVTFCCKCD）肿瘤内注射结合咪喹莫特乳膏局部治疗C57BL/6小鼠TC-1肿瘤模型，结果显示E7多肽+咪喹莫特联合治疗组肿瘤生长速度明显减慢，该组小鼠生存时间显著延长。动物实验提示多肽联合咪喹莫特的免疫治疗具备转化医学价值。.3、.通过体外及体内实验，证实了ATP酶Ino80通过与Nanog的转录起始位点相结合，促进宫颈癌细胞增殖的作用，同时Ino80对于宫颈癌细胞的凋亡、侵袭与迁移没有明显影响。.4、.初步证实靶向癌症的自组装囊泡可以有效地包装和运输药物，提示肿瘤抗原多肽与小分子佐剂与纳米囊泡相结合，在抗肿瘤治疗中可能具有突破性的价值。