TAS2R9 and head and neck squamous cell carcinoma: While a patient survival analysis of TAS2R9 mRNA expression in PDAC patients (n = 150) revealed it was not significantly associated with worse overall survival (OS), higher TAS2R9 expression was an indicator of worse OS in several cancers with dense stroma including breast, ovarian, and head and neck squamous cell carcinoma [31,32,33].