Raw metabolomics dataset of EPI-resistant and non-resistant bladder tumor tissues

The isolated tumor tissues were washed twice with pre-cooled normal saline. For removing proteins and extracting metabolites, the tissues were smashed on ice, followed by suspending in 400 μL of precooled methanol/acetonitrile solvent mixture (MeOH/ACN = 1:1, V/V, Merck, GER), vortexing for 30 s, and then centrifuging at 12,000 × <i>g</i> at 4°C for 20 min. Then the supernatant was incubated at -20°C for 1 h and dried by rotary evaporation. Subsequently, the samples were redissolved into 100 μL of 50% ACN solvent (ACN/H₂O = 1:1, V/V) and vortexed for 30 s. After recentrifuging, the supernatant was subjected to LC-MS analysis (AB Sciex QTRAP 6500 LC-MS/MS platform) for metabolite detection and untargeted metabolomic profiling.