To confirm radiation‐induced cleavage of ICAM‐1 through MMP‐9, we transfected GBM cells with mutant ICAM‐1P404E in which proline in position 404, the cleavage site in ICAM‐1, was substituted with glutamic acid (P404E) (Figure S3G,H, Supporting Information). The gene discussed is MMP9; the disease is glioblastoma.