ERBB3 and head and neck squamous cell carcinoma: Notably, among MAPK-mutated HNSCC patients, we found that those with high IFN-γ, CYT, or T-eff scores (both at 20% and 50% cutoffs) do not significantly overlap with patients of low p-ErbB3 (P = n.s., Fig 6A), suggesting two independent mechanisms operative to contribute the improved outcomes of MAPK pathway-mutant HNSCC.