title: The hyaluronic acid inhibitor 4-methylumbelliferone is an NSMase2 activator-role of Ceramide in MU anti-tumor activity.
abstract: Increased synthesis of hyaluronic acid (HA) is often associated with increased metastatic potential and invasivity of tumor cells. 4-Methylumbelliferone (MU) is an inhibitor of HA synthesis, and has been studied as a potential anti-tumor drug to inhibit the growth of primary tumors and distant metastasis of tumor cells. Although several studies reported that the anticancer effects of MU are mediated by inhibition of HA signaling, the mechanism still needs to be clarified. In a previous study we demonstrated the regulation of HA synthesis by ceramide, and now show how MU activated neutral sphingomyelinase2 (NSMase2) generates ceramides and mediates MU induced inhibition of HA synthesis, cell migration and invasion, and apoptosis of tumor cells. Using a HA enriched mouse oligodendroglioma cell line G26-24 we found that MU elevated the activity of NSMase2 and increased ceramide levels, which in turn increased phosphatase PP2A activity. Further, the activated PP2A reduced phosphorylation of Akt, decreased activities of HA synthase2 (HAS2) and calpains, and inhibited both the synthesis of HA, and the migration and invasion of G26-24 tumor cells. In addition, MU mediated ceramide stimulated activation of p53 and caspase-3, reduced SIRT1 expression and decreased G26-24 viability. The mechanism of the MU anticancer therefore initially involves NSMase2/ceramide/PP2A/AKT/HAS2/caspase-3/p53/SIRT1 and the calpain signaling pathway, suggesting that ceramides play a key role in the ability of a tumor to become aggressively metastatic and grow.
authors.affiliation: Department of Pediatrics, University of Chicago, Chicago, IL 60637, USA. Electronic address: qjingdong@peds.bsd.uchicago.edu.
authors.forename: Jingdong
authors.initials: J
authors.lastname: Qin
authors.affiliation: Department of Pediatrics, University of Chicago, Chicago, IL 60637, USA.
authors.forename: John
authors.initials: J
authors.lastname: Kilkus
authors.affiliation: Department of Pediatrics, University of Chicago, Chicago, IL 60637, USA; Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA. Electronic address: dawg@uchicago.edu.
authors.forename: Glyn
authors.initials: G
authors.lastname: Dawson
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002154:Calpain / Q000235:genetics / Q000378:metabolism; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D002518:Ceramides / Q000096:biosynthesis*; D004789:Enzyme Activation; D015972:Gene Expression Regulation, Neoplastic; D014453:Glucuronosyltransferase / Q000235:genetics / Q000378:metabolism; D006801:Humans; D000076002:Hyaluronan Synthases; D006820:Hyaluronic Acid / Q000037:antagonists & inhibitors* / Q000378:metabolism; D006923:Hymecromone / Q000494:pharmacology*; D051379:Mice; D009457:Neuroglia / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D010766:Phosphorylation / Q000187:drug effects; D054648:Protein Phosphatase 2 / Q000235:genetics / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D056564:Sirtuin 1 / Q000235:genetics / Q000378:metabolism; D013108:Sphingomyelin Phosphodiesterase / Q000235:genetics* / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D002518:Ceramides; D016159:Tumor Suppressor Protein p53; D006923:Hymecromone; D006820:Hyaluronic Acid; D014453:Glucuronosyltransferase; C491099:Has2 protein, mouse; D000076002:Hyaluronan Synthases; D051057:Proto-Oncogene Proteins c-akt; D054648:Protein Phosphatase 2; C491483:Smpd3 protein, mouse; D013108:Sphingomyelin Phosphodiesterase; D002154:Calpain; C505409:Casp3 protein, mouse; D053148:Caspase 3; C470545:Sirt1 protein, mouse; D056564:Sirtuin 1
keywords: 4-Methylumbelliforone; Anticancer; Ceramide; Hyaluronic acid; NSMase2