Degradation of Hexokinase 2 Blocks Glycolysis and Induces GSDME-Dependent Pyroptosis to Amplify Immunogenic Cell Death for Breast Cancer Therapy

Hexokinase 2 (HK2) is the principal rate-limiting enzyme
in the
aerobic glycolysis pathway and determines the quantity of glucose
entering glycolysis. However, the current HK2 inhibitors have poor
activity, so we used proteolysis-targeting chimera (PROTAC) technology
to design and synthesize novel HK2 degraders. Among them, C-02 has the best activity to degrade HK2 protein and inhibit breast
cancer cells. It is demonstrated that C-02 could block
glycolysis, cause mitochondrial damage, and then induce GSDME-dependent
pyroptosis. Furthermore, pyroptosis induces cell immunogenic death
(ICD) and activates antitumor immunity, thus improving antitumor immunotherapy
in vitro and in vivo. These findings show that the degradation of
HK2 can effectively inhibit the aerobic metabolism of breast cancer
cells, thereby inhibiting their malignant proliferation and reversing
the immunosuppressive microenvironment.

己糖激酶2（Hexokinase 2, HK2）是有氧糖酵解通路中的核心限速酶，决定了进入糖酵解途径的葡萄糖总量。然而当前已有的HK2抑制剂活性欠佳，因此本研究采用蛋白水解靶向嵌合体（proteolysis-targeting chimera, PROTAC）技术，设计并合成了新型HK2降解剂。其中化合物C-02展现出最优的HK2蛋白降解活性与乳腺癌细胞增殖抑制效果。研究证实，C-02可阻断糖酵解进程、诱发线粒体损伤，进而诱导GSDME依赖的焦亡。进一步机制研究显示，焦亡可触发免疫原性细胞死亡（immunogenic cell death, ICD）并激活抗肿瘤免疫，最终在体内外均能增强抗肿瘤免疫治疗的疗效。本研究结果表明，靶向降解HK2可有效抑制乳腺癌细胞的有氧代谢，进而阻滞其恶性增殖，并逆转肿瘤免疫抑制微环境。