NOS2 and melanoma: While some studies suggest positive effects of NO [39,40,41], the majority link high NOS2 expression to poor survival across a spectrum of hematological and solid tumors, including breast [8], pancreatic [42], nasopharyngeal carcinoma [43], colorectal [44,45], gastric [46], esophageal [47], prostate [48], melanoma [49], Hodgkin’s lymphoma [50], ovarian [51], squamous cell carcinoma [52], renal cell carcinoma [53], glioma [54], chondrosarcomas [55], Barrett’s esophageal adenocarcinoma [56], and in HCV-infected liver cancer patients [57].