The galectins constitute a large family of carbohydrate-binding proteins with specificity for N-acetyl-lactosamine-containing glycoproteins. Galectin-7 is a prototype monomeric galectin and is specifically expressed in stratified epithelia, notably in epidermis, but is barely detectable in epidermal tumors and significantly down regulated or absent from squamous carconima cell lines. The Galectin-7 gene is induced by tumor suppressor protein p53 transcriptional activity following genotoxic events. Galectin-7 is a proapoptitic protein that functions intracellularly upstream of JNK activation and Cytochrome-c release. It has been shown to increase the susceptibility of keratinocytes to UVB induced apoptosis, an essential processss in the maintenance of epidermal homeostasis.