Galectin-1 as potential therapeutic target for cancer progression

Galectins are a 15-member family of beta-lactoside-specific lectins. They are expressed differentially in normal versus neoplastic tissues and are known to play important roles in biological processes pertinent to cell proliferation, death and migration. Galectin-1 is a hypoxia-regulated protein that exerts potent proangiogenic effects. It is expressed in a large set of human tumor types and is directly implicated in glioma cell migration. Galectin-1 also participates in the resistance of cancer cells to chemotherapy and radiotherapy, and is involved in the activation of the Ras oncogenic pathway. Lastly, galectin-1 is a major player in the tumor immune escape process. Targeting galectin-1 by means of specific antibodies or selective small molecules can not only impair tumor immune escape, cancer cell migration and tumor neoangiogenesis, but also restore a certain level of sensitivity in metastatic tumors to chemo- and radiotherapy. Indeed, antisense oligodeoxynucleotides (ODNs), small interfering RNAs (siRNAs) or selective small molecules can impair the protumoral intracellular functions of galectin-1. Thus, it represents a novel target to combat various types of cancers. This review will provide valuable information for clinicians and researchers who wish to gain an appreciation of the latest endeavors in this field and identify possible new lines of investigation in cancer.