Role of nitric oxide in tumour progression: lessons from human tumours.

摘要: Varied cellular expression and localisation of nitric oxide synthase (NOS) isoforms has been shown in human cancers, including tumours the breast, ovary, stomach, cervix central nervous system. Mapping NOS within tumour tissue from breast gastric cancers shows inducible (iNOS) is expressed predominantly stromal (macrophage endothelial) cells, although level activity at least 1-2 orders magnitude lower than enzyme associated with cytotoxicity apoptosis. There evidence that intratumoural environment may provide chemoattractant signals for monocyte-macrophage recruitment their subsequent activation via interleukin-4, IgE, CD23. Such lead to induction iNOS macrophages vitro. The correlation between grade cancer suggests NO a positive growth signal microenvironment. In vivo studies showing increased rate, vascular density invasiveness cell line transfected constitutively express support this. Furthermore, administration highly selective inhibitor limited invasion rate other murine expressing this isoform. Inhibition generation microenvironment prove useful therapy by preventing angiogenesis, metastasis.