RASSF1 and head and neck squamous cell carcinoma: RASSF1A, TIMP3, and PCQAP/MED15 were found to be hypomethylated in the saliva of HPV-positive HNSCC [79], while RXRG, CTNNA2, GHSR, and ITGA4 were reported hypermethylated in HPV-positive oropharyngeal tumors [80].