肠卫兵清方通过调控结直肠癌免疫微环境和肠道菌群增强 PD-1 抑制剂治疗的抗肿瘤效应。

Chang Wei Qing Decoction enhances the anti-tumor effect of PD-1 inhibitor therapy by regulating the immune microenvironment and gut microbiota in colorectal cancer.

机构信息

Department of Oncology, Putuo Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 200062, China; Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China.

出版信息

Chin J Nat Med. 2023 May;21(5):333-345. doi: 10.1016/S1875-5364(23)60451-0.

DOI:10.1016/S1875-5364(23)60451-0

PMID:37245872

Abstract

The anti-tumor effect of anti-PD-1 antibody has long been shown to be strongly related to the tumor immune microenvironment (TIME). This study aimed to mechanistically assess whether Chang Wei Qing (CWQ) Decoction can enhance the anti-tumor effect of PD-1 inhibitor therapy. PD-1 inhibitor therapy showed the significant anti-tumor effect in patients with mismatch repair-deficient/microsatellite instability-high (dMMR/MSI-H) colorectal cancer (CRC), rather than those with mismatch repair-proficient/microsatellite stable (pMMR/MSS) CRC. Hence, immunofluorescence double-label staining was utilized to explore the difference in the TIME between dMMR/MSI-H and pMMR/MSS CRC patients. Flow cytometry was used to analyze T-lymphocytes in tumors from mice. Western blot was used to measure the expression of PD-L1 protein in mouse tumors. The intestinal mucosal barrier of mice was evaluated by hematoxylin-eosin staining and immunohistochemistry. 16S rRNA-gene sequencing was used to examine the structure of the gut microbiota in mice. Subsequently, Spearmanapos;s correlation analysis was used to analyze the relationship between the gut microbiota and tumor-infiltrating T-lymphocytes. The results showed that dMMR/MSI-H CRC patients had more CD8T cells and higher expression of PD-1 and PD-L1 proteins. In vivo, CWQ enhanced the anti-tumor effect of anti-PD-1 antibody and increased the infiltration of CD8 and PD-1CD8 T cells in tumors. Additionally, the combination of CWQ with anti-PD-1 antibody resulted in lower inflammation in the intestinal mucosa than that induced by anti-PD-1 antibody alone. CWQ and anti-PD-1 antibody co-treatment upregulated PD-L1 protein and reduced the abundance of Bacteroides in the gut microbiota but increased the abundance of Akkermansia,Firmicutes, andActinobacteria. Additionally, the proportion of infiltrated CD8PD-1, CD8, and CD3 T cells were found to be positively correlated with the abundance of Akkermansia. Accordingly, CWQ may modulate the TIME by modifying the gut microbiota and consequently enhance the anti-tumor effect of PD-1 inhibitor therapy.

摘要

抗 PD-1 抗体的抗肿瘤作用早已被证明与肿瘤免疫微环境（TIME）密切相关。本研究旨在从机制上评估肠萎康方是否能增强 PD-1 抑制剂治疗的抗肿瘤作用。PD-1 抑制剂治疗在错配修复缺陷/微卫星不稳定高（dMMR/MSI-H）结直肠癌（CRC）患者中表现出显著的抗肿瘤作用，而在错配修复功能正常/微卫星稳定（pMMR/MSS）CRC 患者中则不然。因此，本研究采用免疫荧光双标染色法探讨 dMMR/MSI-H 和 pMMR/MSS CRC 患者 TIME 之间的差异。流式细胞术分析小鼠肿瘤中的 T 淋巴细胞。Western blot 法测定小鼠肿瘤中 PD-L1 蛋白的表达。采用苏木精-伊红染色和免疫组织化学法评估小鼠肠道黏膜屏障。16S rRNA 基因测序检测小鼠肠道菌群结构。随后，采用 Spearman 相关分析肠道菌群与肿瘤浸润性 T 淋巴细胞之间的关系。结果显示，dMMR/MSI-H CRC 患者 CD8T 细胞较多，PD-1 和 PD-L1 蛋白表达较高。体内实验中，肠萎康方增强了抗 PD-1 抗体的抗肿瘤作用，增加了肿瘤中 CD8 和 PD-1CD8T 细胞的浸润。此外，与单独使用抗 PD-1 抗体相比，肠萎康方联合抗 PD-1 抗体可减轻肠道黏膜炎症。肠萎康方联合抗 PD-1 抗体治疗可上调 PD-L1 蛋白，减少肠道菌群中拟杆菌的丰度，增加阿克曼氏菌、厚壁菌门和放线菌的丰度。此外，浸润的 CD8PD-1、CD8 和 CD3T 细胞的比例与阿克曼氏菌的丰度呈正相关。因此，肠萎康方可能通过调节肠道菌群来调节 TIME，从而增强 PD-1 抑制剂治疗的抗肿瘤作用。