C1R and glioblastoma: Finally, survival analyses across multiple independent GBM cohorts from the Gliovis platform confirmed that high C1R expression was significantly associated with poor prognosis in CGGA‐GBM (p = 0.012), Gravendeel‐GBM (p = 0.002), and Phillips‐GBM (p = 0.019) cohorts (Figure 1F).