Effects of panitumumab on the proteome of treated EGFRvIII glioblastoma cells and on their extracellular vesicles

Panitumumab treatment significantly reduced surface EGFRvIII levels on extracellular vesicles derived from EGFRvIII-positive glioblastoma cells, but no significant decrease was seen in cell lysates. Proteomic analysis showed far more protein changes in vesicles than in parental cells after treatment, mainly involving extracellular matrix organization and collagen-related proteins. The study suggests these vesicles could serve as circulating biomarkers for assessing treatment efficacy and preventing drug resistance.