Indeed, a suppressed pN+ environment may be supported by splicing proteins that are strongly associated with the metastatic phenotype in our HNSCC dataset, and the genes associated with these proteins include SRSF1, SRSF2, SRSF3, SRSF5, and TRA2A, and also the immune marker CD209 (Fig. 4d). Here, CD209 is linked to head and neck squamous cell carcinoma.