Depletion of creatine phosphagen energetics with a covalent creatine kinase inhibitor. Nature chemical biology Creatine kinases (CKs) provide local ATP production in periods of elevated energetic demand, such as during rapid anabolism and growth. Thus, creatine energetics has emerged as a major metabolic liability in many rapidly proliferating cancers. Whether CKs can be targeted therapeutically is unknown because no potent or selective CK inhibitors have been developed. Here we leverage an active site cysteine present in all CK isoforms to develop a selective covalent inhibitor of creatine phosphagen energetics, CKi. Using deep chemoproteomics, we discover that CKi selectively engages the active site cysteine of CKs in cells. A co-crystal structure of CKi with creatine kinase B indicates active site inhibition that prevents bidirectional phosphotransfer. In cells, CKi and its analogs rapidly and selectively deplete creatine phosphate, and drive toxicity selectively in CK-dependent acute myeloid leukemia. Finally, we use CKi to uncover an essential role for CKs in the regulation of proinflammatory cytokine production in macrophages. 10.1038/s41589-023-01273-x

Creatine uptake regulates CD8 T cell antitumor immunity. Di Biase Stefano,Ma Xiaoya,Wang Xi,Yu Jiaji,Wang Yu-Chen,Smith Drake J,Zhou Yang,Li Zhe,Kim Yu Jeong,Clarke Nicole,To Angela,Yang Lili The Journal of experimental medicine T cells demand massive energy to combat cancer; however, the metabolic regulators controlling antitumor T cell immunity have just begun to be unveiled. When studying nutrient usage of tumor-infiltrating immune cells in mice, we detected a sharp increase of the expression of a () gene, which encodes a surface transporter controlling the uptake of creatine into a cell. Using knockout mice, we showed that creatine uptake deficiency severely impaired antitumor T cell immunity. Supplementing creatine to WT mice significantly suppressed tumor growth in multiple mouse tumor models, and the combination of creatine supplementation with a PD-1/PD-L1 blockade treatment showed synergistic tumor suppression efficacy. We further demonstrated that creatine acts as a "molecular battery" conserving bioenergy to power T cell activities. Therefore, our results have identified creatine as an important metabolic regulator controlling antitumor T cell immunity, underscoring the potential of creatine supplementation to improve T cell-based cancer immunotherapies. 10.1084/jem.20182044

Creatine transport and creatine kinase activity is required for CD8 T cell immunity. Cell reports The factors that promote T cell expansion are not fully known. Creatine is an abundant circulating metabolite that has recently been implicated in T cell function; however, its cell-autonomous role in immune-cell function is unknown. Here, we show that creatine supports cell-intrinsic CD8 T cell homeostasis. We further identify creatine kinase B (CKB) as the creatine kinase isoenzyme that supports these T cell properties. Loss of the creatine transporter (Slc6a8) or Ckb results in compromised CD8 T cell expansion in response to infection without influencing adenylate energy charge. Rather, loss of Slc6a8 or Ckb disrupts naive T cell homeostasis and weakens TCR-mediated activation of mechanistic target of rapamycin complex 1 (mTORC1) signaling required for CD8 T cell expansion. These data demonstrate a cell-intrinsic role for creatine transport and creatine transphosphorylation, independent of their effects on global cellular energy charge, in supporting CD8 T cell homeostasis and effector function. 10.1016/j.celrep.2022.110446