Glioblastoma is the most prevalent and aggressive form of brain cancer. With a median overall survival of ~20 months under current standard therapy (surgery, chemotherapy, radiotherapy), novel treatment approaches are desperately needed. Immunotherapies are being investigated in clinical trials but failed so far. This includes a recent phase II clinical trial with a personalized immunotherapy based on tumor lysate-charged dendritic cells (NCT01213407). Here, we investigated tumor tissue from patients from this trial to explore glioblastoma (immuno)resistance factors and strategies to overcome them. We followed an innovative approach of combining mass spectrometry-based quantitative proteomics (n=36) with microRNA sequencing plus RT-qPCR (n=38). Protein quantification identified e.g. huntingtin interacting protein 1 (HIP1), retinol binding protein 1 (RBPP1), ferritin heavy chain (FTH1) and focal adhesion kinase 2 (FAK2) as resistance factor candidates. MicroRNA analysis identified miR-216b, miR-216a, miR-708 and let-7i as molecules potentially associated with overcoming resistance as they were enriched in patients with a comparably longer survival. In silico pathway prediction indicated they down-regulate the focal adhesion pathway – among others. FAK2 was enriched in short-term surviving immunotherapy patients. In vitro, FAK inhibitors prevented the formation of glioblastoma cell adhesion in the form of gliomaspheres. Taken together, we here mapped possible drivers of glioblastoma’s immuno)resistance in one of the largest DC vaccination tissue analysis cohorts so far – demonstrating usefulness and feasibility of combined proteomics/miRNomics approaches. Future research should investigate agents that sensitize glioblastoma to (immuno)therapy – e.g. targeting focal adhesion. Small-molecule inhibitors or microRNAs capable of altering multiple pathways at once are candidates to explore.