PDGFRB and head and neck squamous cell carcinoma: The cohort was divided into two based on the mean expression of genes associated with myofibroblasts (ACTA2, CDH2, PDGFRA, PDGFRB, VIM, S100A4) to examine the prognostic significance of the ECM module hub gene COL3A1 (the most connected gene, representative of the ECM module expression) within HNSCC cases with a myofibroblastic stroma; this analysis showed COL3A1 expression is associated with poor survival (Log Rank p=0.019; Fig. 6E).