Inhibition of ACLY overcomes cancer immunotherapy resistance via polyunsaturated fatty acids peroxidation and cGAS-STING activation.

Adenosine 5'-triphosphate citrate lyase (ACLY) is a cytosolic enzyme that converts citrate into acetyl-coenzyme A for fatty acid and cholesterol biosynthesis. ACLY is up-regulated or activated in many cancers, and targeting ACLY by inhibitors holds promise as potential cancer therapy. However, the role of ACLY in cancer immunity regulation remains poorly understood. Here, we show that ACLY inhibition up-regulates PD-L1 immune checkpoint expression in cancer cells and induces T cell dysfunction to drive immunosuppression and compromise its antitumor effect in immunocompetent mice. Mechanistically, ACLY inhibition causes polyunsaturated fatty acid (PUFA) peroxidation and mitochondrial damage, which triggers mitochondrial DNA leakage to activate the cGAS-STING innate immune pathway. Pharmacological and genetic inhibition of ACLY overcomes cancer resistance to anti-PD-L1 therapy in a cGAS-dependent manner. Furthermore, dietary PUFA supplementation mirrors the enhanced efficacy of PD-L1 blockade by ACLY inhibition. These findings reveal an immunomodulatory role of ACLY and provide combinatorial strategies to overcome immunotherapy resistance in tumors.

[Spectrum-activity relationship of trichosanthis fructus and trichosanthis fructus strip pieces for rat myocardial ischemia-reperfusion injury].

To investigate the spectrum-activity relationship of Trichosanthis Fructus and Trichosanthis Fructus strip pieces for rat myocardial ischemia-reperfusion injury. HPLC fingerprints of Trichosanthis Fructus and Trichosanthis Fructus strip pieces were established, and the values of creatinekinase-MB (CK-MB), myoglobin (MYO) and cardiac troponin-T (cTNT) in 3 dose groups (2.25, 13.5, 27.0 g·kg⁻¹, equivalent to the crude herb g·kg⁻¹) of Trichosanthis Fructus and Trichosanthis Fructus strip pieces with myocardial ischemia-reperfusion injury in rats were measured, and the grey relational analysis was used to study the spectrum-activity relationship of Trichosanthis Fructus and Trichosanthis Fructus strip pieces for rat myocardial ischemia-reperfusion injury. With the dosage increase from 2.25 g·kg⁻¹ to 27.0 g·kg⁻¹, the correlation degree of spectrum-activity relationship of Trichosanthis Fructus and Trichosanthis Fructus strip pieces was also enhanced, but the change trend was different between these two groups. According to the frequency of the top 10 peaks in the correlation degree, peak 17, 14, 16, 19, 32, 12, 26, 30, 4, 6 and 2 were the basic effective substances group of Trichosanthis Fructus, peak 6,14,12,32,30,4 and 6 were the basic effective substances group of Trichosanthis Fructus strip pieces. Peak 6, 14, 12, 32, 30, 4 and 26 in fingerprints of Trichosanthis Fructus and Trichosanthis Fructus strip pieces were the main common pharmacodynamic substance base, among them, peak 6 was 5-hydroxymethyl furfural, peak 14 was vanillic acid and the peak 28 was rutin, but the correlation degree with the efficacy was different. The effect of Trichosanthis Fructus and Trichosanthis Fructus strip pieces on rat myocardial ischemia-reperfusion injury was due to the synergistic effect of the effective substance groups related to the dosage. The essential pharmacodynamic substance groups of Trichosanthis Fructus and Trichosanthis Fructus strip pieces were different, but they shared a common active ingredient group.