RUNX3 regulates trastuzumab resistance of gastric cancer cells: a metabolomic analysis based on UPLC-Q Exactive Focus Orbitrap mass spectrometry / 南方医科大学学报

OBJECTIVE@#To explore the role of Runt-related transcription factor 3 (RUNX3) in metabolic regulation of trastuzumab-resistant gastric cancer cells and investigate the mechanism of RUNX3 knockdown-mediated reversal of trastuzumab resistance.@*METHODS@#We performed a metabolomic analysis of trastuzumab-resistant gastric cancer cells (NCI N87R) and RUNX3 knockdown cells (NCI N87R/RUNX3) using ultra performance liquid chromatography (UPLC) coupled with Q Exactive Focus Orbitrap mass spectrometry (MS). Multivariate combined with univariate analyses and MS/MS ion spectrums were used to screen the differential variables. MetaboAnalyst 5.0 database was employed for pathway enrichment analysis. Differential metabolites-genes regulatory relationships were constructed based on OmicsNet database. The changes in GSH/GSSG and NADPH/NADP ratios in NCI N87R/RUNX3 cells were measured using detection kits.@*RESULTS@#The metabolic profile of NCI N87R cells was significantly altered after RUNX3 knockdown, with 81 differential metabolites identified to contribute significantly to the classification, among which 43 metabolites were increased and 38 were decreased (P < 0.01). In NCI N87R cells, RUNX3 knockdown resulted in noticeable alterations in 8 pathways involving glutamine metabolism, glycolysis, glycerophospholipid, nicotinate-nicotinamide and glutathione metabolism, causing also significant reduction of intracellular GSH/GSSG and NADPH/NADP ratios (P < 0.01). The differential metabolites-genes network revealed a regulatory relationship between the metabolic molecules and genes.@*CONCLUSION@#RUNX3 reverses trastuzumab resistance in gastric cancer cells by regulating energy metabolism and oxidation-reduction homeostasis and may serve as a potential therapeutic target for trastuzumab-resistant gastric cancer.

Balneotherapy and Platelet Glutathione Metabolism / 日本温泉気候物理医学会雑誌

Two experiments were performed to clarify the effects of balneotherapy on platelet glutathione metabolism. One experiment, in which healthy men were subjected to water immersion at temperatures of 25°C, 36°C, and 42°C for 10min, showed that the level of platelet lipid peroxides (LPO) tended to increase at 25°C and 42°C, suggesting the presence of oxidative stress at these temperatures. When an antioxidative defense system was induced at these temperatures, the levels of platelet glutathione (GSH), glutathione peroxidase (GPX) and glutathione reductase (GR) activities increased. The other experiment, in which 4 weeks of balneotherapy was applied to type II (non-insulin-dependent) diabetic patients, showed that the level of GSH on admission correlated well with that of fasting plasma glucose (FPG, r=0.692, p<0.050). After 4 weeks of balneotherpy, the level of GSH increased (p<0.01) in well-controlled patients (FPG<150mg/dl) and decreased (p<0.05) in poorly controlled patients (FPG≥150mg/dl), There was a negative correlation between GPX activities and the level of FPG (r=-0.430, p<0.05). After the balneotherapy, the activity increased in five patients, decreased in three patients, and showed no changes in four patients.<br>These results indicate that, in diabetic patients, 1) platelet GSH synthesis is obviously induced in response to oxidative stress, 2) lowered GPX activities suggest an impaired antioxidative defense system, and 3) platelet glutathione metabolism was partly improved by 4 weeks of balneotherapy but depended on the control status of plasma glucose levels. From these findings, we conclude that 1) patients whose platelet antioxidative defense system is damaged such as those with diabetes mellitus should not take hot or cold bath, and that 2) balneotherapy improves platelet glutathione metabolism, leading to normalization of platelet aggregability.