Arsenic trioxide (As2O3, ATO) is a clinically utilized anticancer drug that primarily achieves its therapeutic effects by targeting specific protein markers. Proteomic studies on ATO in Diffuse Large B-Cell Lymphoma (DLBCL) have not been previously conducted. In this study, LC-MS/MS was employed to scrutinize the proteomics of DLBCL upon ATO treatment in Daudi cells. The intact proteome of DLBCL in response to arsenic trioxide was profiled for both ATO-treated and non-treated Daudi cells