Xu Dongbo, Wang Li, Wieczorek Kyle, Zhang Yali, Wang Zinian, Wang Jianmin, Xu Bo, Singh Prashant K, Wang Yanqing, Zhang Xiaojing, Wu Yue, Smith Gary J, Attwood Kristopher, Zhang Yuesheng, Goodrich David W, Li Qiang
Department of Urology, Roswell Park Comprehensive Cancer Center, Buffalo, NY 14203, USA.
Department of Biostatistics & Bioinformatics, Roswell Park Comprehensive Cancer Center, Buffalo, NY 14203, USA.
Cancers (Basel). 2022 May 19;14(10):2511. doi: 10.3390/cancers14102511.
Approximately 80% of patients with advanced bladder cancer do not respond to immune checkpoint inhibitor (ICI) immunotherapy. Therefore, there is an urgent unmet need to develop clinically relevant preclinical models so that factors governing immunotherapy responses can be studied in immunocompetent mice. We developed a line of mouse triple knockout (TKO: Trp53, Pten, Rb1) urothelial carcinoma organoids transplanted into immunocompetent mice. These bladder tumors recapitulate the molecular phenotypes and heterogeneous immunotherapy responses observed in human bladder cancers. The TKO organoids were characterized in vivo and in vitro and compared to the widely used MB49 murine bladder cancer model. RNAseq analysis of the TKO tumors demonstrated a basal subtype. The TKO xenografts demonstrated the expression of urothelial markers (CK5, CK7, GATA3, and p63), whereas MB49 subcutaneous xenografts did not express urothelial markers. Anti-PD-1 immunotherapy resulted in a mixed pattern of treatment responses for individual tumors. Eight immune cell types were identified (basophils, B cells, dendritic cells, macrophages, monocytes, neutrophils, NK cells, and T cells) in ICI-treated xenografts. Responder xenografts displayed significantly increased immune cell infiltration (15.3%, 742 immune cells/4861 total cells) compared to the non-responder tumors (10.1%, 452 immune cells/4459 total cells, Fisher Exact Test p < 0.0001). Specifically, there were more T cells (1.0% vs. 0.4%, p = 0.002) and macrophages (8.6% vs. 6.4%, p = 0.0002) in responder xenografts than in non-responder xenografts. In conclusion, we have developed a novel preclinical model that exhibits a mixed pattern of response to anti-PD-1 immunotherapy. The higher percentage of macrophage tumor infiltration in responders suggests a potential role for the innate immune microenvironment in regulating ICI treatment responses.
大约80%的晚期膀胱癌患者对免疫检查点抑制剂（ICI）免疫疗法无反应。因此，迫切需要开发具有临床相关性的临床前模型，以便在具有免疫活性的小鼠中研究影响免疫疗法反应的因素。我们构建了一系列移植到具有免疫活性小鼠体内的小鼠三基因敲除（TKO：Trp53、Pten、Rb1）尿路上皮癌类器官。这些膀胱肿瘤重现了人类膀胱癌中观察到的分子表型和异质性免疫疗法反应。对TKO类器官进行了体内和体外特征分析，并与广泛使用的MB49小鼠膀胱癌模型进行了比较。对TKO肿瘤的RNAseq分析显示为基底亚型。TKO异种移植瘤显示尿路上皮标志物（CK5、CK7、GATA3和p63）的表达，而MB49皮下异种移植瘤不表达尿路上皮标志物。抗PD-1免疫疗法对个体肿瘤产生了混合的治疗反应模式。在接受ICI治疗的异种移植瘤中鉴定出八种免疫细胞类型（嗜碱性粒细胞、B细胞、树突状细胞、巨噬细胞、单核细胞、中性粒细胞、NK细胞和T细胞）。与无反应肿瘤（10.1%，452个免疫细胞/4459个总细胞，Fisher精确检验p<0.0001）相比，有反应的异种移植瘤显示免疫细胞浸润显著增加（15.3%，742个免疫细胞/4861个总细胞）。具体而言，有反应的异种移植瘤中的T细胞（1.0%对0.4%，p = 0.002）和巨噬细胞（8.6%对6.4%，p = 0.0002）比无反应的异种移植瘤更多。总之，我们开发了一种新型临床前模型，该模型对抗PD-1免疫疗法表现出混合的反应模式。有反应者中巨噬细胞肿瘤浸润百分比更高，提示固有免疫微环境在调节ICI治疗反应中可能发挥作用。
