Scientists at the National Cancer Institute at Frederick executed a series of studies aimed at identifying markers that can be used to distinguish between proliferating blood vessels in normal and diseased tissues.
The researchers systematically examined gene-expression patterns in the endothelial cells that line blood vessels derived from normal resting tissues, regenerating tissues, and tumors. A comparison of the normal vessels revealed several organ-specific endothelial genes that could potentially aid in the delivery of molecular medicine to specific anatomical sites. The study also revealed 13 genes that are selectively overexpressed in tumor blood vessels. Although the function of most of the newly identified genes in tumor blood vessels is unclear, many of the genes encode cell surface proteins, making them appealing targets for the development of new therapeutic agents.
One of the cell surface proteins identified, called CD276, was found to be frequently overexpressed in the blood vessels of a variety of human cancers. The researchers also report that in many of the tumors examined, CD276 was also overexpressed by the tumor cells, making this protein a particularly attractive target because a suitable inhibitory molecule might be able to deliver a double blow: one to the tumor cells themselves and the other to the blood vessels that feed it.
The study is published in the June issue of Cancer Cell.