The promoter-specific expression of GluR6 isoforms in neuronal and non-neuronal cells was confirmed by performing RT-PCR of mRNAs isolated from brain tissue, normal fibroblasts, and 18 tumor cell lines representing breast carcinoma, prostate carcinoma, ovarian carcinoma, melanoma, astrocytoma, and glioblastoma. This evidence concerns the gene GRIK2 and glioblastoma.