TGFB1 and head and neck squamous cell carcinoma: Regardless of this variation in LWR and proliferation, TGF‐β stimulation increased invasion in 3D organ culture for all four TGF‐β‐responsive HNSCC keratinocyte populations and correlated with p‐EMT score when all six HNSCC keratinocyte populations were compared (Figure 2F), suggesting that TGF‐β‐responsive keratinocytes invade collagen/MatrigelTM organ cultures and this invasion can be enhanced further by the addition of TGF‐β1.