调控肾型谷氨酰胺酶活性的重组溶瘤腺病毒治疗肝细胞肝癌研究

Reprogrammed metabolism, immunosuppression and stem-like cells are major hurdles for effective therapy of hepatocellular carcinoma(HCC) in clinic. Kidney-type glutaminase (GLS1) is a rate-limiting enzyme of glutaminolysis. Our previous studies showed that GLS1 was markedly upregulated in HCC, and was an excellent biomarker in pathological diagnosis and clinical prognosis of HCC. In addition, GLS1 was closely related to the epithelial mesenchymal transition (EMT), tumor stemness and immune escape. Thus, GLS1 could be a potential therapeutic target of HCC. Self-replicative oncolytic viruses exert not only direct tumor killing, but also robustly induce antitumor immunity, so-called viro-immunotherapy, and in parallel, express genes of interest in tumor loci. In this study, we intend to construct a recombinant oncolytic adenovirus expressing a mutant GLS1, an enzyme lack of the enzymatic activity while interrupts normal function of endogenous GLS1 through competitive inhibition. Thus, the recombinant AD5-GLS1 mutant may possess the following functions : 1) disturbing cancer metabolism, 2) inhibiting the process of EMT and tumor stemness, 3) blocking the GLS1-related or oncolytic viruses induced immune suppression, 4) inducing anti-tumor immunity. We will investigate its therapeutic efficacy and the underlying mechanisms in vitro and in vivo. This study sophisticatedly integrates the advantages of therapeutics targeting cancer metabolism and immunotherapy. The results will provide a novel therapeutic strategy so-called viro-metabo-immunotherapy for HCC.

肝细胞肝癌的代谢重编程、免疫耐受及其干性等是临床治疗的难点。肾型谷氨酰胺酶（GLS1）是肿瘤谷氨酰胺酵解的限速酶，我们前期证实，GLS1是肝癌诊断和预后评估的生物标志物，且与肿瘤上皮间质转化（EMT）进程、肿瘤的干性及免疫逃逸密切相关。因此，GLS1是肿瘤治疗的潜在靶点。具有复制功能的重组溶瘤病毒不仅能够直接溶瘤，还能有效激活抗肿瘤免疫，即溶瘤免疫治疗，并在肿瘤局部表达目的基因。本项目拟构建表达突变型GLS1的重组溶瘤腺病毒，该突变型GLS1缺失酶活功能，竞争性干扰癌细胞GLS1的正常功能，从而干扰肿瘤代谢、抑制EMT进程、肿瘤干性，并解除GLS1或溶瘤腺病毒所介导的免疫耐受；同时，利用溶瘤病毒在肿瘤局部强大的免疫活化功能，在肝癌体外和体内模型中研究其疗效和机制。本课题有机地整合了代谢和免疫治疗的优势，为肝癌提供一个全新的溶瘤代谢免疫治疗策略。

肝细胞肝癌的代谢重编程、免疫耐受及其干性等是临床治疗的难点。肾型谷氨酰胺酶（GLS1）是肿瘤谷氨酰胺酵解的限速酶，我们前期证实，GLS1是肝癌诊断和预后评估的生物标志物，且与肿瘤上皮间质转化（EMT）进程、肿瘤的干性及免疫逃逸密切相关。因此，GLS1是肿瘤治疗的潜在靶点。具有复制功能的重组溶瘤病毒不仅能够直接溶瘤，还能有效激活抗肿瘤免疫，即溶瘤免疫治疗，并在肿瘤局部表达目的基因。本项目拟构建表达突变型GLS1的重组溶瘤腺病毒，该突变型GLS1缺失酶活功能，竞争性干扰癌细胞GLS1的正常功能，从而干扰肿瘤代谢、抑制EMT进程、肿瘤干性，并解除GLS1或溶瘤腺病毒所介导的免疫耐受；同时，利用溶瘤病毒在肿瘤局部强大的免疫活化功能，在肝癌体外和体内模型中研究其疗效和机制。本课题有机地整合了代谢和免疫治疗的优势，为肝癌提供一个全新的溶瘤代谢免疫治疗策略。