title: The mechanism of the anticancer function of M1 macrophages and their use in the clinic.
abstract: M1-type macrophages are capable of inducing lysis in various types of cancer cells, but the mechanism of action is unclear. It has been noted that an "unknown protein" produced together with protease by activated macrophages is responsible for this action. Activated M1 macrophages have been recently reported to produce family 18 chitinases, all of which have been named chitotriosidase. Our experiments have demonstrated that family 18 chitinases work together with proteases and can damage various cancer cells both in vitro and in vivo. Thus, in this article, we suggest that the 50-kDa chitotriosidase is the reported "unknown protein". In addition, we discuss how to properly stimulate activated M1 macrophages to produce 50-kDa chitotriosidases and proteases for destroying cancer cells. Because family 19 chitinase has recently been reported to kill cancer cells, we also discuss the possibility of directly using human family 18 chitotriosidase and the humanized plant family 19 chitinase for cancer treatment.
authors.affiliation: College of Pharmacy, Ohio State University, Columbus, OH 43215, USA. pan_xingpan@yahoo.com
authors.forename: Xing-Qing
authors.initials: XQ
authors.lastname: Pan
mesh_terms: D000818:Animals; D018906:Antineoplastic Agents, Alkylating / Q000494:pharmacology; D002688:Chitinases / Q000378:metabolism*; D003520:Cyclophosphamide / Q000494:pharmacology; D006596:Hexosaminidases / Q000378:metabolism; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology; D008262:Macrophage Activation / Q000276:immunology*; D008264:Macrophages / Q000145:classification / Q000201:enzymology / Q000276:immunology* / Q000473:pathology; D009369:Neoplasms / Q000276:immunology* / Q000473:pathology; D010447:Peptide Hydrolases / Q000378:metabolism; D050378:T-Lymphocytes, Regulatory / Q000378:metabolism; D018417:Th1 Cells / Q000378:metabolism; D018418:Th2 Cells / Q000378:metabolism
chemical_list: D018906:Antineoplastic Agents, Alkylating; D007166:Immunosuppressive Agents; D003520:Cyclophosphamide; D006596:Hexosaminidases; C086400:chitotriosidase; D002688:Chitinases; D010447:Peptide Hydrolases