HPSE and head and neck squamous cell carcinoma: This notion, together with our report here on induction of the heparanase gene by HPV16 E6, and the fact that HPV positivity also correlates with HNSCC aggressiveness 3, suggest that in HPV-driven oral tumourigenesis heparanase represents a novel downstream effector responsible for aggressive phenotype of HPV-positive HNSCC.