GLIPR1 and glioblastoma: We found that the mean expression of RTVP-1 was significantly higher in the mesenchymal subtype (P < 0.0001) compared to the proneural, GCIMP, neural and the classical GBM subtypes (Fig. 1A), whereas its expression was significantly lower in the GCIMP subtype compared with the other GBM subtypes (Fig. 1A, Suppl.