PTPRC and neoplasm: Patients with MM simultaneouslyhad both CD45-positive and CD45-negative tumor cells[67].The increased CD45 expression enhances the sensitivity ofMM cells to 17-dimethylaminoethylamino- 17-demethoxygeldanamycin, an inhibitorof HSP90 chaperone [67], and variousapoptotic stimuli (e.g., oxidative stress and endoplasmic reticulum stress)[68].