MT-CO2 and head and neck squamous cell carcinoma: Another investigation showed that curcumin (33) induces apoptosis in head and neck squamous cell carcinoma (HNSCC) through suppression of NFKB mediated by NFKBIA/IκBα kinase inhibition and, consequently, results in the suppression of cell survival and cell proliferative genes, including BCL2, CCND1, MT-CO2/COX-2, IL6 (interleukin 6) and MMP9 (matrix metallopeptidase 9) [292].