Additionally, in the TCGA HNSCC cohort higher tumor grading correlated with higher MERTK mRNA (p < 0.001, Supplementary Table S4) and for the Bonn HNSCC cohort the same trend was evident (p = 0.246, Table 1, Jonckheere trend test p = 0.094). Here, MERTK is linked to head and neck squamous cell carcinoma.