TP53 and head and neck cancer: Compared to GendicineTM, phase 1 and 2 clinical trials were carried out to evaluate Ad5CMV-p53 (INGN 201; ADVEXIN, Austin, TX, USA), a similar adenoviral p53 gene therapy reagent developed by Introgen in the US, for use in local advanced bladder, lung, head and neck cancer, and glioma by intra-tumoral injection [39,40,41,42,43,44].