神经系统药物硫利哒嗪和氯雷他定联合TLR7免疫佐剂杀伤结肠癌细胞的分子机制研究

The colon contains a large number of independent activity nerve cells, which participate in the communication of the gut-brain axis. Colon cancer has been one of the most malignant tumors in our country due to the disorder of cell signaling pathway. Our previous experiments showed that, thioridazine and loratadine significantly inhibited the proliferation of colon cells after screening six common nervous system drugs. The thiordazine and loratadine could be used as potential drugs for the treatment of colon cancer. However, tumor specificity and immune escape is one of the bottlenecks in the clinic. TLR receptor agonists have been used as tumor vaccine adjuvants to enhance the efficacy of tumor immunotherapy. Based on the above results, thioridazine and lotatadine were combined with TLR7 small molecule agonist R848 to further improve the immune therapeutic effect for colon cancer both in vitro and in vivo. Overcoming the immunosuppressive mechanism caused by colon cancer, the aim is to develop a new powerful and specific drug for the treatment of colon cancer. Thus, it provides a promising strategy for the development of colon cancer vaccine, and plans to open up a new path for joint preventive and therapeutic vaccines.

结肠内含大量的可独立活动的神经细胞，参与肠脑神经轴的交流活动，细胞信号通路紊乱导致的结肠癌已成为我国恶性程度最高的肿瘤之一。我们前期的实验表明，通过筛选6种常见的神经系统药物发现，硫利哒嗪和氯雷他定的联合应用在体内外显示出更有效的抗结肠癌的效应，并且该机制主要是靶向PI3K/Akt/mTOR信号通路。因此提示硫利哒嗪和氯雷他定联合应用可作为结肠癌的潜在治疗药物，但是肿瘤特异性以及免疫逃逸是其进入临床的瓶颈之一。TLR受体激动剂已经被用作肿瘤疫苗佐剂而增强肿瘤免疫治疗的效果。基于以上结果，本课题拟联合硫利哒嗪和氯雷他定药物以及TLR7小分子免疫激动剂R848进一步提高体内外对结肠癌的免疫治疗作用，克服结肠癌本身造成的免疫抑制机制，旨在开发一种新的强效，特异性的治疗结肠癌的药物。从而为结肠癌肿瘤疫苗的发展提供新的策略，同时还计划在联合预防性和治疗性疫苗方面开辟新的道路。

结直肠癌是世界上第三大常见恶性肿瘤。我们以前的研究表明，联合使用硫利哒嗪和氯雷他定可以有效地抑制结直肠癌。然而，由于缺乏治疗特异性和免疫逃逸等问题，这些研究结果在临床上的应用受到了阻碍。Toll样受体（TLR）激动剂被用作增强肿瘤疫苗有效性的佐剂。本研究的目的是评价硫利哒嗪和氯雷他定联合小分子TLR7激动剂Resiqumoid （R848）对小鼠结直肠癌生长的抑制作用。24只BALB/c小鼠随机分为PBS、R848、硫利哒嗪和氯雷他定或硫利哒嗪和氯雷他定联合R848组。用酶联免疫吸附实验（ELISA）测定细胞因子水平。记录总生存率、肿瘤体积和肿瘤重量。细胞毒性通过计数CD8和CD3阳性或CD4和CD3阳性的T细胞数量来测定。用硫利哒嗪和氯雷他定联合R848组处理小鼠，细胞因子（如IFN-r、IL-6和TNF-a）诱导的免疫应答显著增强。此外，硫利哒嗪和氯雷他定联合R848组显著延缓肿瘤的发展和延长生存期，这与增强免疫应答和树突状细胞成熟有关。本研究提示硫利哒嗪和氯雷他定和R848的联合治疗可以有效克服肿瘤细胞的免疫逃逸，在结直肠癌治疗中具有广阔的应用前景。