Paclitaxel (Taxol): an inhibitor of angiogenesis in a highly vascularized transgenic breast cancer

Cancer Biother Radiopharm. 1999 Feb;14(1):31-6. doi: 10.1089/cbr.1999.14.31.


Paclitaxel (Taxol), a promoter of microtubule polymerization and a radiosensitizing agent, is one of the more active anticancer drugs in the current treatment of solid tumors. In this study, we show that paclitaxel possesses an antiangiogenic property associated with a down-regulation of vascular endothelial growth factor (VEGF) in a highly-vascularized transgenic murine breast cancer (Met-1). Paclitaxel, at non-cytotoxic doses of 0, 3 and 6 mg/kg/day, was administered intraperitoneally for 5 days to nude mice bearing the Met-1 breast tumor. Extent of intratumoral angiogenesis, as indicated by microvessel tortuosity and microvessel density, was significantly reduced by paclitaxel in a dose-dependent manner. Paclitaxel also suppressed expression of VEGF in the Met-1 cells transplanted in nude mice or maintained in cell culture. These results indicate that antiangiogenesis associated with a down-regulation of VEGF is an additional mode of action of paclitaxel.

MeSH terms

  • Angiogenesis Inhibitors / administration & dosage
  • Angiogenesis Inhibitors / therapeutic use*
  • Animals
  • Antineoplastic Agents, Phytogenic / administration & dosage
  • Antineoplastic Agents, Phytogenic / therapeutic use*
  • Endothelial Growth Factors / biosynthesis
  • Endothelial Growth Factors / genetics
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Gene Expression Regulation, Neoplastic / drug effects
  • Injections, Intraperitoneal
  • Lymphokines / biosynthesis
  • Lymphokines / genetics
  • Mammary Neoplasms, Experimental / blood supply
  • Mammary Neoplasms, Experimental / drug therapy*
  • Mice
  • Mice, Nude
  • Mice, Transgenic
  • Microcirculation
  • Neoplasm Proteins / biosynthesis
  • Neoplasm Proteins / genetics
  • Paclitaxel / administration & dosage
  • Paclitaxel / therapeutic use*
  • Vascular Endothelial Growth Factor A
  • Vascular Endothelial Growth Factors


  • Angiogenesis Inhibitors
  • Antineoplastic Agents, Phytogenic
  • Endothelial Growth Factors
  • Lymphokines
  • Neoplasm Proteins
  • Vascular Endothelial Growth Factor A
  • Vascular Endothelial Growth Factors
  • Paclitaxel