NOS3 and gastric cancer: Six genes, namely, GNAS complex locus (GNAS), C-X-C motif chemokine receptor 4 (CXCR4), protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B), adenylate cyclase 6 (ADCY6), 5′-nucleotidase Ecto (NT5E), and nitric oxide synthase 3 (NOS3), which make up the adenosine signature, were used to stratify patients according to their risk for GC prognosis.