Lin Jing, Liu Fei, Gao Fei, Chen Yujia, Wang Renling, Wang Xinyue, Li Yue, Li Qi, Sun Shihui, Li Zi, Lan Yungang, Lu Huijun, Guo Wei, Du Li, Gao Feng, Song Deguang, Zhao Kui, Guan Jiyu, He Wenqi
State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research of the Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun 130062, China.
Department of Laboratory Animals, College of Animal Science, Jilin University, 130062 Changchun, China.
Biochim Biophys Acta Mol Basis Dis. 2022 Dec 1;1868(12):166538. doi: 10.1016/j.bbadis.2022.166538. Epub 2022 Sep 9.
Traditionally, vesicular stomatitis virus (VSV) and other oncolytic viruses (OVs) are thought to kill tumors by inducing apoptosis. However, cell apoptosis leads to immune quiescence, which is incompatible with the ability of OVs to activate the antitumor immune microenvironment. Thus, studying OVs-mediated oncolytic mechanisms is of great importance for the clinical application of OVs.
We examined the pyroptosis in tumor cells and tissues by morphological observation, Lactate Dehydrogenase (LDH) assay, frozen section observation, and western-blotting techniques. The critical role of GSDME in VSV-induced pyroptosis was confirmed by CRISPR/Cas9 technique. VSV virotherapy-recruited cytotoxic lymphocytes in the tumors were examined by flow cytometry assay. VSV-activated antitumor immunity was further enhanced by the co-administration with anti-PD-1 antibody.
Here, we observed that VSV was able to trigger tumor pyroptosis through Gasdermin E (GSDME) in tumor cells, human tumor samples, and tumor-bearing mouse models. Importantly, the effectiveness of VSV-based virotherapy is highly dependent on GSDME, as depletion of GSDME not only reverses VSV-induced tumor-suppressive effects but also diminishes the ability of VSV to activate antitumor immunity. Notably, VSV treatment makes immunologically 'cold' tumors more sensitive to checkpoint blockade.
Oncolytic VSV induces tumor cell pyroptosis by activating GSDME. GSDME is critical in recruiting cytotoxic T lymphocytes in the context of VSV therapy, which can switch immunologically 'cold' tumors into 'hot' and enhance immune checkpoint therapy efficacy.
传统上，水泡性口炎病毒（VSV）和其他溶瘤病毒（OVs）被认为通过诱导细胞凋亡来杀死肿瘤。然而，细胞凋亡会导致免疫静止，这与OVs激活抗肿瘤免疫微环境的能力不相容。因此，研究OVs介导的溶瘤机制对于OVs的临床应用具有重要意义。
我们通过形态学观察、乳酸脱氢酶（LDH）测定、冰冻切片观察和蛋白质免疫印迹技术检测肿瘤细胞和组织中的细胞焦亡。通过CRISPR/Cas9技术证实了GSDME在VSV诱导的细胞焦亡中的关键作用。通过流式细胞术检测肿瘤中VSV病毒疗法招募的细胞毒性淋巴细胞。通过与抗PD-1抗体联合给药进一步增强VSV激活的抗肿瘤免疫力。
在此，我们观察到VSV能够在肿瘤细胞、人肿瘤样本和荷瘤小鼠模型中通过Gasdermin E（GSDME）触发肿瘤细胞焦亡。重要的是，基于VSV的病毒疗法的有效性高度依赖于GSDME，因为GSDME的缺失不仅会逆转VSV诱导的肿瘤抑制作用，还会削弱VSV激活抗肿瘤免疫的能力。值得注意的是，VSV治疗使免疫“冷”肿瘤对检查点阻断更敏感。
溶瘤性VSV通过激活GSDME诱导肿瘤细胞焦亡。GSDME在VSV治疗的背景下招募细胞毒性T淋巴细胞中起关键作用，它可以将免疫“冷”肿瘤转变为“热”肿瘤，并增强免疫检查点治疗的疗效。
