title: Docetaxel versus paclitaxel for antiangiogenesis.
abstract: Cytoskeleton-toxic chemotherapeuticals, such as vinblastine and paclitaxel, display antiangiogenic activity. This study was designed to compare paclitaxel to its analog docetaxel and assess their doses still antiangiogenic in vitro and in vivo. Human endothelial cell functions involved in angiogenesis, namely proliferation, chemotaxis, morphogenesis, and secretion of matrix metalloproteinase-2 (MMP-2), MMP-9, and urokinase-type plasminogen activator (uPA) were studied in vitro upon exposure to docetaxel and paclitaxel, whereas their effect on angiogenesis was studied in vivo by using the chick embryo chorioallantoic membrane (CAM) model. Proliferation of mouse embryo fibroblasts and human Kaposi's sarcoma, breast and endometrial carcinoma, and lymphoid tumor cells was also studied. In vitro, 0.5, 0.75, and 1 nM docetaxel and 2, 3, and 4 nM paclitaxel, i.e., non-cytotoxic doses, impacted all endothelial cell functions, but not protease secretion, in a dose-dependent fashion, whereas they did not affect the proliferation of other cells, except those of Kaposi's sarcoma. No apoptosis was induced by 0.5 nM docetaxel and 2 nM paclitaxel, and moderate apoptosis was induced by 1 nM docetaxel and 4 nM paclitaxel. The antiangiogenic effect rapidly disappeared on drug suspension and was accompanied ultrastructurally by thin lesions of cytoskeleton in the form of slight and equally reversible depolymerization and accumulation of microfilaments. Massive endothelial cell apoptosis with evident cytotoxicity and irreversibility were associated with 2 nM docetaxel and 5 nM paclitaxel, although these higher doses were ineffective on other cells except Kaposi's sarcoma cells. In vivo, 1, 2, and 3 nM docetaxel and 4, 8, and 12 nM paclitaxel displayed a dose-dependent antiangiogenic activity. We suggest that very low docetaxel and paclitaxel doses selectively cause organic and functional damage of endothelial cells and that docetaxel is four times stronger. Their antiangiogenic activity could be applied to treat Kaposi's sarcoma and cancers.
authors.affiliation: Department of Biomedical Sciences and Human Oncology (DIMO), University of Bari Medical School, Policlinico, Piazza Giulio Cesare 11, I-70124 Bari, Italy.
authors.forename: Angelo
authors.initials: A
authors.lastname: Vacca
authors.forename: Domenico
authors.initials: D
authors.lastname: Ribatti
authors.forename: Monica
authors.initials: M
authors.lastname: Iurlaro
authors.forename: Francesca
authors.initials: F
authors.lastname: Merchionne
authors.forename: Beatrice
authors.initials: B
authors.lastname: Nico
authors.forename: Roberto
authors.initials: R
authors.lastname: Ria
authors.forename: Franco
authors.initials: F
authors.lastname: Dammacco
mesh_terms: D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002633:Chemotaxis / Q000187:drug effects; D002642:Chick Embryo; D000077143:Docetaxel; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000648:ultrastructure; D006801:Humans; D020782:Matrix Metalloproteinases / Q000378:metabolism; D018919:Neovascularization, Physiologic / Q000187:drug effects; D017239:Paclitaxel / Q000031:analogs & derivatives* / Q000494:pharmacology*; D043823:Taxoids; D014471:Umbilical Veins / Q000166:cytology; D014568:Urokinase-Type Plasminogen Activator / Q000378:metabolism
chemical_list: D020533:Angiogenesis Inhibitors; D043823:Taxoids; D000077143:Docetaxel; D014568:Urokinase-Type Plasminogen Activator; D020782:Matrix Metalloproteinases; D017239:Paclitaxel