Thyroid cancer is the most prevalent
endocrine cancer worldwide. Angiogenesis, the formation of new blood vessels, plays a pivotal role in the development and progression of
tumors. Over the past years,
cancer research has focused on the ability of
tumors to induce newly formed blood vessel, because
tumor growth and the process of
cancer metastasis mainly depends on angiogenesis.
Tumor neovascularization occurs following the imbalance between pro-angiogenic and anti-angiogenic factors until the
tumor switches to an angiogenic phenotype. A number of signaling factors and receptors that are implicated in the regulation of angiogenesis have been identified and characterized; most notably, the
vascular endothelial growth factors (
VEGFs) family and their receptors, which are the main pro-angiogenic molecules during early development and in pathological conditions such as
cancer. Although thyroid is a highly vascularized organ, angiogenic switch in
tumors of this organ leads to the formation of a vast network of blood vessels that favors the dissemination of
tumor cells to distant organs and results in deterioration of patient conditions. Accordingly, the identification of key angiogenic
biomarkers for
thyroid cancer can facilitate diagnosis, prognosis and clinical decision-making and also may help to discover targeting factors for effective
cancer therapy as well as monitoring response to
therapy. Hence, the main purposes of this review are to summarize the types and mechanisms of angiogenesis emphasizing the prominent factors implicated in
thyroid cancer angiogenesis.