TSPO and neoplasm: Both TSPO mRNA and TSPO protein expression were higher in healthy corresponding tissue compared to tumor (p < 0.001) (Figures 6B, C), showing significantly lower TSPO expression in tumors originating from the oral cavity (p = 0.001), larynx (p = 0.002), tonsils (p = 0.031), and tongue (p < 0.001) (Supplementary Figure S3A).