Sun Yi, Maggs Luke, Panda Apekshya, Wright Samuel J, Cicerchia Angelina M, Jenney Anne, Perricone Matthew D, Mills Caitlin E, Cattaneo Giulia, Ventin Marco, Chen Feng, Rasmussen Martin Q, Miranda Alex, Revach Or-Yam, Fang Jacy, Fu Amina, Bowling Peter J, Sharova Tatyana, Lawless Aleigha, Sorger Peter K, Bardeesy Nabeel, Wang Xinhui, Flaherty Keith T, Boland Genevieve M, Mehta Arnav, Sade-Feldman Moshe, Ferrone Cristina R, Jenkins Russell W
Mass General Cancer Center, Krantz Family Center for Cancer Research, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.
Broad Institute of MIT and Harvard, Cambridge, Massachusetts.
Cancer Immunol Res. 2025 Feb 3;13(2):210-228. doi: 10.1158/2326-6066.CIR-23-1011.
Novel therapeutic strategies are needed to improve the efficacy of chimeric antigen receptor (CAR) T cells as a treatment of solid tumors. Multiple tumor microenvironmental factors are thought to contribute to resistance to CAR T-cell therapy in solid tumors, and appropriate model systems to identify and examine these factors using clinically relevant biospecimens are limited. In this study, we examined the activity of B7-H3-directed CAR T cells (B7-H3.CAR-T) using 3D microfluidic cultures of patient-derived organotypic tumor spheroids (PDOTS) and then confirmed the activity of B7-H3.CAR T cells in PDOTS. Although B7-H3 expression in PDOTS was associated with B7-H3.CAR-T sensitivity, mechanistic studies revealed dynamic upregulation of co-inhibitory receptors on CAR T-cells following target cell encounter that led to CAR T-cell dysfunction and limited efficacy against B7-H3-expressing tumors. PD-1 blockade restored CAR T-cell activity in monotypic and organotypic tumor spheroids with improved tumor control and upregulation of effector cytokines. Given the emerging role of TANK-binding kinase 1 (TBK1) as an immune evasion gene, we examined the effect of TBK1 inhibition on CAR T-cell efficacy. Similar to PD-1 blockade, TBK1 inhibition restored CAR T-cell activity in monotypic and organotypic tumor spheroids, prevented CAR T-cell dysfunction, and enhanced CAR T-cell proliferation. Inhibition or deletion of TBK1 also enhanced the sensitivity of cancer cells to immune-mediated killing. Taken together, our results demonstrate the feasibility and utility of ex vivo profiling of CAR T cells using PDOTS and suggest that targeting TBK1 could be used to enhance CAR T-cell efficacy by overcoming tumor-intrinsic and -extrinsic resistance mechanisms.
需要新的治疗策略来提高嵌合抗原受体（CAR）T细胞治疗实体瘤的疗效。多种肿瘤微环境因素被认为导致了实体瘤对CAR T细胞疗法的耐药性，而使用临床相关生物样本识别和检测这些因素的合适模型系统有限。在本研究中，我们使用患者来源的器官型肿瘤球体（PDOTS）的3D微流控培养物检测了B7-H3导向的CAR T细胞（B7-H3.CAR-T）的活性，然后在PDOTS中证实了B7-H3.CAR T细胞的活性。尽管PDOTS中B7-H3的表达与B7-H3.CAR-T敏感性相关，但机制研究显示，CAR T细胞在遇到靶细胞后共抑制受体的动态上调，导致CAR T细胞功能障碍和对表达B7-H3肿瘤的疗效有限。PD-1阻断恢复了单型和器官型肿瘤球体中CAR T细胞的活性，改善了肿瘤控制并上调了效应细胞因子。鉴于TANK结合激酶1（TBK1）作为免疫逃逸基因的新作用，我们检测了TBK1抑制对CAR T细胞疗效的影响。与PD-1阻断类似，TBK1抑制恢复了单型和器官型肿瘤球体中CAR T细胞的活性，防止了CAR T细胞功能障碍，并增强了CAR T细胞的增殖。抑制或缺失TBK1也增强了癌细胞对免疫介导杀伤的敏感性。总之，我们的结果证明了使用PDOTS对CAR T细胞进行体外分析的可行性和实用性，并表明靶向TBK1可用于通过克服肿瘤内在和外在的耐药机制来增强CAR T细胞的疗效。
