iNOS immunoreactivity in gastric carcinoma tissue. (A) A focal/weak/luminal immunoreaction is observed in a well-differentiated adenocarcinoma case. (B) Intense/diffuse/cytoplasmic iNOS immunoreactivity is observed in a poorly differentiated tumor tissue. (C) No iNOS expression was detected in non-neoplastic glands in the same case. (D) Despite focal/weak iNOS immunoreactivity in well-differentiated tumor areas, there is strong iNOS expression in tumor cells of the invasive phenotype. iNOS immunoreactivity is demonstrated in endothelial cells (E) and fibroblasts (F) in the tumor stroma.
Karadayı et al. Diagnostic Pathology 2013 8:151 doi:10.1186/1746-1596-8-151