The landscape of taste receptors in glioblastoma

Taste receptors, including bitter (TAS2Rs), sweet (TAS1R2/TAS1R3), and umami (TAS1R1/TAS1R3) receptors, have recently attracted attention in cancer research due to their emerging relevance in tumour biology. Glioblastoma is the most common and aggressive primary brain tumour, yet its chemosensory properties remain poorly characterised and taste receptor expression has not previously been investigated in this type of cancer. Here, we performed a comprehensive characterisation of taste receptor expression in glioblastoma using human astrocytes, three glioblastoma cell lines, and human tumour samples. Transcript analysis identified 20 of the 26 human TAS2Rs, as well as TAS1R2/TAS1R3 and TAS1R1/TAS1R3, in glioblastoma cell lines. Selected receptors (TAS2R4, TAS2R5, TAS2R14, TAS2R39, and TAS1R2/TAS1R3) were further examined at the protein level by Western blot and immunocytochemistry, confirming their presence across the tested models. Immunohistochemistry in tumour samples from 13 glioblastoma patients demonstrated variable receptor expression, revealing receptor-specific distribution patterns within tumour tissue. In addition, the taste-signalling protein GNAT3 was detected in glioblastoma cells, supporting the presence of the taste pathway components. Together, these findings provide the first transcript and protein-level mapping of taste receptors in glioblastoma, establishing a molecular atlas of these chemosensory receptors in cell models and human tumours. This work lays a foundation for future studies investigating the biological significance of taste receptors in glioblastoma.