Tumor-induced neoangiogenesis and receptor tyrosine kinases - Mechanisms and strategies for acquired resistance

Background: Angiogenesis is essential for tumor growth, proliferation and metastasis. Tumor-related angiogenesis is complex and involves multiple signaling pathways. Controlling angiogenesis is a promising strategy for limiting cancer progression.

Scope of review: Several receptor tyrosine kinases influence the angiogenic response via multiple signaling molecules and pathways. Understanding the functional interaction of kinases in the angiogenic process and development of resistance to kinase inhibition is essential for future successful therapeutic strategies.

Major conclusions: Strategies that target receptor tyrosine kinases and other tumor microenvironment factors simultaneously, or sequentially, are required for achieving an efficient and robust anti-angiogenic response.

General significance: Understanding the molecular mechanism of angiogenesis has improved, and has led, to the clinical development and approval of anti-angiogenic drugs. While many patients have benefited from these agents, their limited efficacy and the development of resistance remains a challenge. This review highlights current therapies and challenges associated with targeting angiogenesis in cancer.