使用有效免疫佐剂对核酸进行先天免疫感应对于增强针对癌症的保护性免疫反应至关重要。干扰素基因刺激剂 (STING) 和 Toll 样受体 9 (TLR9​​) 激动剂被认为是多种临床前肿瘤模型中的有希望的候选药物，并有可能在临床环境中使用。然而，这种治疗对肿瘤基质的影响目前尚不清楚。在这项研究中，我们研究了 ADU-S100 作为 STING 激动剂和 CpG ODN1826 作为 TLR9 激动剂在结肠癌临床前模型中的免疫治疗效果。荷瘤小鼠在肿瘤接种后第 10 天和第 16 天用 ADU-S100 和 CpG ODN1826 进行瘤内治疗。评估肿瘤和脾脏中的细胞因子谱、肿瘤细胞凋亡、免疫细胞的浸润以及肿瘤微环境（TME）中的癌症相关成纤维细胞（CAF），以确定治疗后的免疫机制。单一和联合治疗的强大抗肿瘤活性、肿瘤和脾脏中促炎细胞因子表达的上调以及免疫细胞对TME的募集和浸润揭示了免疫佐剂在根除结肠癌模型中的协同作用。值得注意的是，TME 中 CAF 的显着下调表明免疫辅助治疗后肿瘤发生受到抑制。结果说明了将 STING 和 TLR9 通路作为强大的免疫佐剂治疗临床前结肠癌的潜力，以及在未来治疗方法中利用这些通路的可能性。版权所有 © 2023 Hajiabadi、Alidadi、Montakhab Farahi、Ghahramani Seno、Farzin 和 Haghparast 。

The innate immune sensing of nucleic acids using effective immunoadjuvants is critical for increasing protective immune responses against cancer. Stimulators of interferon genes (STING) and toll-like receptor 9 (TLR9) agonists are considered promising candidates in several preclinical tumor models with the potential to be used in clinical settings. However, the effects of such treatment on tumor stroma are currently unknown. In this study, we investigated the immunotherapeutic effects of ADU-S100 as a STING agonist and CpG ODN1826 as a TLR9 agonist in a preclinical model of colon carcinoma. Tumor-bearing mice were treated intratumorally on days 10 and 16 post-tumor inoculation with ADU-S100 and CpG ODN1826. Cytokine profiles in the tumor and spleen, tumor cell apoptosis, the infiltration of immune cells, and cancer-associated fibroblasts (CAFs) in the tumor microenvironment (TME) were evaluated to identify the immunological mechanisms after treatment. The powerful antitumor activity of single and combination treatments, the upregulation of the expression of pro-inflammatory cytokines in the tumor and spleen, and the recruitment and infiltration of the TME by immune cells revealed the synergism of immunoadjuvants in the eradication of the colon carcinoma model. Remarkably, the significant downregulation of CAFs in the TME indicated that suppression of tumorigenesis occurred after immunoadjuvant therapy. The results illustrate the potential of targeting the STING and TLR9 pathways as powerful immunoadjuvants in the treatment of preclinical colon carcinoma and the possibility of harnessing these pathways in future therapeutic approaches.Copyright © 2023 Hajiabadi, Alidadi, Montakhab Farahi, Ghahramani Seno, Farzin and Haghparast.