In light of the observation that the functional inhibition of EGFR by AG1478, PTHrP silencing by RNA interference (RNAi), and combined application of these reagents exerted a prominent anti-tumoral effect, these findings raise the possibility to utilize both PTHrP and EGFR as therapeutic targets in oral squamous cell carcinoma. This evidence concerns the gene PTHLH and oral cavity squamous cell carcinoma.