During the cancerous transformation of normal hepatocytes into hepatocellular carcinoma (HCC), the enzyme catalyzing the first rate-limiting step of glycolysis, namely the glucokinase (GCK), is replaced by the higher affinity isoenzyme, hexokinase 2 (HK2). Here, we show that in HCC tumors the highest expression level of HK2 is inversely correlated to GCK expression, and is associated to poor prognosis for patient survival. To further explore functional consequences of the GCK-to-HK2 isoenzyme switch occurring during carcinogenesis, HK2 was knocked-out in the HCC cell line Huh7 and replaced by GCK, to generate the Huh7-GCK⁺/HK2⁻ cell line. HK2 knockdown and GCK expression rewired central carbon metabolism, stimulated mitochondrial respiration and restored essential metabolic functions of normal hepatocytes such as lipogenesis, VLDL secretion, glycogen storage. It also reactivated innate immune responses and sensitivity to natural killer cells, showing that consequences of the HK switch extend beyond metabolic reprogramming.

在正常肝细胞向肝细胞癌 (HCC) 的癌变过程中，催化糖酵解的第一个限速步骤的酶，即葡萄糖激酶 (GCK)，被更高亲和力的同工酶己糖激酶 2 (HK2) 取代。在这里，我们表明在 HCC 肿瘤中，HK2的最高表达水平与GCK表达呈负相关，并且与患者生存的不良预后有关。为了进一步探索在致癌过程中发生的 GCK-to-HK2 同工酶转换的功能后果，HK2在 HCC 细胞系 Huh7 中被敲除并被GCK取代，以产生Huh7- GCK ⁺ / HK2 ^-细胞系。HK2 敲低和 GCK 表达重新连接中央碳代谢，刺激线粒体呼吸并恢复正常肝细胞的基本代谢功能，如脂肪生成、VLDL 分泌、糖原储存。它还重新激活了先天免疫反应和对自然杀伤细胞的敏感性，表明 HK 转换的后果超出了代谢重编程的范围。