Galectins in the tumor endothelium: opportunities for combined cancer therapy.

Galectins are emerging as a family of proteins that play an important role in several steps of tumorigenesis. Evidence is accumulating that galectins are expressed by the tumor endothelium, where they contribute to different steps of tumor progression such as immune escape and metastasis. Recent studies have identified an important role for galectins in tumor angiogenesis. Moreover, it has been shown that galectins in the endothelium can be targeted for therapeutic applications. This opens a window of opportunity for the development of tumor-type independent treatment strategies. This review focuses on the expression of galectins in the tumor endothelium, their contribution to tumor progression, and their application in tumor-type independent cancer therapy.