Complementary Actions of Inhibitors of Angiopoietin-2 and VEGF on Tumor Angiogenesis and Growth

Researchers at the University of California's Comprehensive Cancer Center have discovered that inhibiting the actions of angiopoietin-2 (Ang2) and vascular endothelial growth factor (VEGF) can significantly slow tumor growth. Their study, published in Cancer Research, found that combining the two inhibitors resulted in a 91% reduction in tumor growth over 26 days, compared to a 62% reduction when Ang2 was inhibited alone.

Key Takeaways:

• Inhibition of Ang2 reduced the number of vascular sprouts by 46% and tumor growth by 62% over 26 days.
• Combination of Ang2 and VEGF inhibition resulted in a 82% reduction in sprouts, 67% reduction in tumor vascularity, and 91% reduction in tumor growth.
• The reduction in tumor growth was accompanied by decreased cell proliferation and increased apoptosis.
• The study used a human colon carcinoma model in nude mice, with 34 mice per group.
• The researchers concluded that inhibition of Ang2 slows tumor growth by limiting the expansion of the tumor vasculature by sprouting angiogenesis.
• The study suggest that a combination of Ang2 and VEGF inhibitors may be a useful therapeutic approach for treating colon cancer.

Statistics:

• 46% reduction in vascular sprouts when Ang2 was inhibited.
• 62% reduction in tumor growth when Ang2 was inhibited.
• 82% reduction in sprouts when Ang2 and VEGF inhibitors were combined.
• 67% reduction in tumor vascularity when Ang2 and VEGF inhibitors were combined.
• 91% reduction in tumor growth when Ang2 and VEGF inhibitors were combined.
• 34 mice per group in the study.
• 26 days duration of the tumor growth study.

Sources:

• Hashizume, H. et al. (2010). Complementary actions of inhibitors of angiopoietin-2 and VEGF on tumor angiogenesis and growth. Cancer Research, 70(6), 2213-223.
• University of California, Comprehensive Cancer Center.