ICOS 表达的 CAR-T 细胞介导三阴性乳腺癌及其转移灶的持久消除。

ICOS-expressing CAR-T cells mediate durable eradication of triple-negative breast cancer and metastasis.

机构信息

Medical Research Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, China.

Department of Breast Surgery, the Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China.

出版信息

J Immunother Cancer. 2024 Nov 11;12(11):e010028. doi: 10.1136/jitc-2024-010028.

DOI:10.1136/jitc-2024-010028

PMID:39532433

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11555110/

Abstract

BACKGROUND

The failure of conventional therapies and the propensity for recurrence and metastasis make triple-negative breast cancer (TNBC) a formidable challenge with grim prognoses and diminished survival rates. Immunotherapy, including immune checkpoint blockade and chimeric antigen receptor (CAR)-T cell therapy, presents innovative and potentially more effective strategies for addressing TNBC. Within this context, the inducible costimulator (ICOS), a member of the CTLA4/CD28 family, plays a crucial role in regulating immune responses and T-cell differentiation by binding to its ligand ICOSL. However, the impact of the ICOS/ICOSL axis on cancer varies.

METHODS

In this study, immunohistochemistry was conducted to examine the expression level of ICOSL in TNBC tumor tissues. We developed ICOS-enhanced B7H3-CAR-T cells (ICOS-B7H3-CAR) using the third-generation CAR-T cell technology, which featured magnified ICOS expression and targeted the B7H3 antigen. Xenograft and metastasis models of TNBC were conducted to examine the cytotoxicity and durability of CAR-T cells in tumors. Overexpression and CRISPR/Cas9-mediated knockout (KO) techniques were employed to regulate the expression of ICOSL on TNBC cell lines.

RESULTS

Notably, we observed elevated ICOSL expression in TNBC tumor tissues, which correlated with poor survival prognosis in patients with TNBC. Compared with conventional B7H3-CAR-T cells, ICOS-B7H3-CAR-T cells significantly inhibited the tumor growth of TNBC cells both in vitro and in vivo, accompanied by increased secretion of cytokines such as interferon gamma and tumor necrosis factor alpha. Furthermore, the in vivo experiments illustrated that ICOS-B7H3-CAR-T cells exhibited prolonged antitumor activity and could effectively eradicate metastases in a TNBC metastasis model, consequently extending survival. Importantly, manipulating the expression of ICOSL on TNBC cells through overexpression or KO significantly influenced the function of ICOS-B7H3-CAR-T cells. This suggests that the level of ICOSL expression on TNBC cells is critical for enhancing the potent antitumor effects of ICOS-B7H3-CAR-T cells.

CONCLUSION

Overall, our study highlights the potential clinical application of ICOS as a promising strategy for combating TNBC recurrence and metastasis.

摘要

背景

传统疗法的失败以及复发和转移的倾向，使得三阴性乳腺癌（TNBC）成为一个严峻的挑战，预后不佳，生存率降低。免疫疗法，包括免疫检查点阻断和嵌合抗原受体（CAR）-T 细胞疗法，为解决 TNBC 提供了创新的、潜在更有效的策略。在这种情况下，诱导共刺激因子（ICOS）是 CTLA4/CD28 家族的一员，通过与其配体 ICOSL 结合，在调节免疫反应和 T 细胞分化方面发挥着关键作用。然而，ICOS/ICOSL 轴对癌症的影响是不同的。

方法

本研究通过免疫组织化学方法检测了 TNBC 肿瘤组织中 ICOSL 的表达水平。我们使用第三代 CAR-T 细胞技术构建了 ICOS 增强的 B7H3-CAR-T 细胞（ICOS-B7H3-CAR），该技术具有放大的 ICOS 表达和针对 B7H3 抗原的靶向性。我们还构建了 TNBC 的异种移植和转移模型，以研究 CAR-T 细胞在肿瘤中的细胞毒性和持久性。我们还采用过表达和 CRISPR/Cas9 介导的敲除（KO）技术来调节 TNBC 细胞系中 ICOSL 的表达。

结果

值得注意的是，我们观察到 TNBC 肿瘤组织中 ICOSL 的表达升高，这与 TNBC 患者的不良生存预后相关。与传统的 B7H3-CAR-T 细胞相比，ICOS-B7H3-CAR-T 细胞在体外和体内均显著抑制了 TNBC 细胞的肿瘤生长，同时伴随着干扰素 γ和肿瘤坏死因子 α 等细胞因子的分泌增加。此外，体内实验表明，ICOS-B7H3-CAR-T 细胞具有延长的抗肿瘤活性，可有效清除 TNBC 转移模型中的转移灶，从而延长生存时间。重要的是，通过过表达或 KO 来操纵 TNBC 细胞上 ICOSL 的表达水平，显著影响了 ICOS-B7H3-CAR-T 细胞的功能。这表明 TNBC 细胞上 ICOSL 的表达水平对于增强 ICOS-B7H3-CAR-T 细胞的强大抗肿瘤作用至关重要。