The combination of PDT and curcumin in lung carcinoma cells and in laryngeal squamous cell carcinoma cells induced an upregulation of caspase-9 and caspase-3, suggesting that the intrinsic pathway (caspase 9) is involved in the curcumin-PDT-induced death of tumor cells [58, 69]. This evidence concerns the gene CASP3 and laryngeal squamous cell carcinoma.