FOS and head and neck squamous cell carcinoma: Studies carried out by our group and others in last 5 years have clearly demonstrated the differential expression and activity of host transcription factors particularly AP1, NF-κB and STAT3 in HPV-positive HNSCC or the transcript profile of their downstream genes (Mishra et al., 2006; Gaykalova et al., 2015; Verma et al., 2017).