However, although it was clearly observed that both HNSCC lines showed more mesenchymal characteristics than CSCC lines (higher migration rate, reduced E-cadherin expression and increased mesenchymal markers N-cadherin, vimentin and snail), which has been associated with increased resistance to various treatments, no relationship with PDT efficacy was observed in our case47–49. The gene discussed is CDH2; the disease is head and neck squamous cell carcinoma.