CHRNA5 and head and neck squamous cell carcinoma: We then compared the differentially expression of transcripts in “CHRNA5 High” HNSCC patients with a smoking history versus “CHRNA5 Low” HNSCC patients with a smoking history and observed that transcripts upregulated in CHRNA5 High HNSCC tumors were involved in DNA repair processes (ex: Base Excision Repair, Homologous Recombination, etc.)whereas transcripts downregulated in CHRNA5 High tumors were involved immune regulation pathways (Th1 and Th2 cell differentiation, JAK-STAT signaling pathway, etc.)(Figure 1F).