IGF1R and head and neck squamous cell carcinoma: We used the proximity ligation assay (PLA; ref. 29) to detect the IGF1R-containing receptor complex in human HNSCC cell lines and in oropharyngeal and adenoid cystic tumor microarrays (TMA), and tested whether SSTNIGF1R induced ASK1 activity and reduced cell growth and survival in HNSCC cell lines in vitro and patient-derived tumor xenografts (PDX) in vivo.