Bortezomib treatment of HPV+ HNSCC cell lines has previously been associated with p53 stabilisation and induction of p53-dependent cell cycle arrest and apoptosis.36 Here we show that bortezomib induces restoration of p53 and induction of the p53 target protein p21 in all HPV+ cell lines tested with the exception of 147 T cells that already showed a marked basal p53 expression (Figure 5a). Here, TP53 is linked to head and neck squamous cell carcinoma.