MAPK1 and head and neck squamous cell carcinoma: Based on our findings from this study, together with the previously shown effects of odorant activated olfactory receptor genes on MAPK signaling pathways16, 24, 25, 28, and our group’s recent report on MAPK1/ERK2 as novel target genes for cancer pain29, it could be hypothesized that olfactory receptor genes, upstream effectors of the MAPK signaling cascade, may serve as novel target genes for pre-treatment pain in HNSCC patients.