PDPN and head and neck squamous cell carcinoma: Our EMT transcription factor analysis, focusing on those transcription factors reported to interact with the promoters of PDPN, VIM, and PAI1, identified two groups that correlated with the level of invasion of HNSCC keratinocytes with or without fibroblasts (Figure 6), suggesting that specific transcription factors influence endogenous invasion while others are more important for tumor cell–CAF interactions.