To investigate whether the inhibition of hypoxia-induced enzymes CA IX/XII could augment the efficacy of low doses of Cis-Pt against HNSCC, FaDu and SCC-011 cell lines were grown under hypoxic conditions and treated with Cis-Pt (1 μM), the specific CAIX/XII inhibitor SLC-0111 (100 μM) and combination of the two drugs for 72 h. Here, CA9 is linked to head and neck squamous cell carcinoma.