title: Methylene blue induces cytotoxicity in human brain tumor cells.
abstract: Methylene blue (MB), a known inhibitor of guanylyl cyclase, induced cytotoxicity in SK-N-MC human neuroblastoma and U-373 MG human astrocytoma cells in a dose-dependent manner. MB did not significantly alter cellular levels of cGMP in both cells. 8-Br cGMP, a membrane-permeable analogue of cGMP, did not decrease MB-induced cytotoxicity, indicating that cGMP may not be a major target of the cytotoxic action of MB. However, hydroxyl radical scavengers or intracellular Ca2+ modulators effectively blocked the MB-induced cytotoxicity. These results suggest that hydroxyl radical and intracellular Ca2+ may have an important involvement in the cytotoxic action of MB. These results further suggest that the treatment with MB may be useful for the therapeutic applications of human brain tumors.
authors.affiliation: Department of Neurological Surgery, Loyola University Medical Center, Maywood, IL 60153.
authors.forename: Y S
authors.initials: YS
authors.lastname: Lee
authors.forename: R D
authors.initials: RD
authors.lastname: Wurster
mesh_terms: D001254:Astrocytoma / Q000473:pathology*; D001932:Brain Neoplasms / Q000473:pathology*; D002118:Calcium / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D006152:Cyclic GMP / Q000378:metabolism; D006801:Humans; D007424:Intracellular Fluid / Q000378:metabolism; D007700:Kinetics; D008751:Methylene Blue / Q000633:toxicity*; D009447:Neuroblastoma / Q000473:pathology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D017382:Reactive Oxygen Species; D006152:Cyclic GMP; D002118:Calcium; D008751:Methylene Blue