In an effort to prevent the growth of vascular tumors, several disrupting agents have been produced, and some are being researched. The goal is to minimize the threat of cancerous tumors. In this piece, we will look at few disrupting agents currently making the wave.

Since 1971, multiple compounds that are anti-angiogenic in nature have been discovered. Some of them have even demonstrated clear clinical benefits for patients with cancer. For decades, tumor angiogenesis has become the new target in combating the growth and metastasis of solid tumors.

Besides inhibitors of tumor angiogenesis, with effects on the formation of new blood vessels, there is another class of drugs called vascular disrupting agents (VDAs) which target endothelial cells of the already established tumor vessels. VDAs have two types: small molecules and ligand-directed VDAs.

These small molecules are further subdivided into two classes. These are: the tubulin-binding agents and the synthetic flavonoids - induces local production of cytokines. Ligand-directed VDAs involves targeting moieties that are combined with the aim of delivering toxic compounds selectively to the tumor vascular network.

Today, tumor vasculature is now a well-recognized therapeutic which target blood vessels, sustaining tumor growth and enable spread and formation of distant metastases. It is aimed at inducing tumors to stimulate the formation of their own blood vessels (angiogenesis).

In 1971, Judah Folkman discovered that tumors cannot grow beyond a certain level (1–2 mm3) without the support of a system to supply blood. Also, he hypothesized that blocking tumor angiogenesis would go a long way at controlling cancer growth and metastasis.

As already noted, extensive research has been carried out on the molecular mechanisms of tumor angiogenesis and critical control points that can be useful therapeutically. There are two goals of therapeutic applications of tumor angiogenesis - blocking the formation of new vessels (antiangiogenic strategies) and disrupting tumor vessels that are already recognized (vascular disrupting strategies).

It should be noted that tumor vessels differ from normal Vascular Tumors. Usually, tumor vasculature is leaky, tortuous, and has irregular caliber with sluggish blood flow and increased vascular resistance when compared with tumor vessels.

Also, vascular tumors have vessels that differ from each other. This heterogeneity has therapeutic implications when some agents that target tumor vessels are used. When it comes to solid malignancies, vessels in the tumor center often form a chaotic network of thin-walled, leaky, and tortuous vessels that greatly rely on constant survival stimuli from vascular growth factors secreted by tumor, stromal or inflammatory cells. Thus, VDAs are important to inhibit the growth of these tumors.