Cellular and Molecular Biology



Expression, localization and function of galectin-8, a tandem-repeat lectin, in human tumors

María T. Elola1, Fátima Ferragut1, Víctor M. Cárdenas Delgado1, Lorena G. Nugnes1, Lucas Gentilini2, Diego Laderach2, María F. Troncoso1, Daniel Compagno2, Carlota Wolfenstein-Todel1 and Gabriel A. Rabinovich2,3

1Institute of Biochemistry and Biophysics (IQUIFIB), UBA-CONICET, Department of Biological Chemistry, School of Pharmacy and Biochemistry. University of Buenos Aires, 2Laboratory of Functional Glycomics, IQUIBICEN, CONICET, Department of Biological Chemistry, School of Exact and Natural Sciences, University of Buenos Aires and 3Laboratory of Immunopathology, Institute of Experimental Biology and Medicine (IBYME), CONICET, Buenos Aires, Argentina

Offprint requests to: María Teresa Elola, PhD, Instituto de Química y Fisicoquímica Biológicas Prof. Dr. Alejandro Paladini (UBA-CONICET). Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires. Junín 956 (C1113), Buenos Aires, Argentina. e-mail: mt_elola@yahoo.com

Summary. Galectin-8 (Gal-8) is a ‘tandem-repeat’-type galectin, which possesses two carbohydrate recognition domains connected by a linker peptide. Gal-8 complexity is related to the alternative splicing of its mRNA precursor, which is known to generate isoforms. Regarding its carbohydrate-binding specificity, Gal-8 has a unique feature among galectins, since its C-terminal domain has higher affinity for N-glycan-type branched oligosaccharides, while its N-terminal domain shows strong affinity for α2-3-sialylated or 3’-sulfated ß-galactosides. We integrate here the available information on Gal-8 expression in different tumor types and attempt to elucidate associations of its expression and localization during tumor progression with the overarching goal of analyzing its potential applications in diagnosis and prognosis. Differential diagnosis is still a prime concern in tumor pathology, and Gal-8 could be of great value in some types of primary or secondary tumors (i.e. papillary thyroid carcinoma, advanced colon carcinoma from patients with distant metastases, or metastases from primary lung carcinoma). The prognostic value of Gal-8 has been described for laryngeal carcinoma as well as advanced colon carcinoma. Further studies are needed to explain the relevance of Gal-8 and its isoforms in tumor pathology and their different intra- or extracellular roles (cytoplasmic, nuclear or extracellular) in tumor biology. Histol Histopathol 29, 1093-1105 (2014)

Key words: Galectin-8, Isoforms, Tumors, Lung, Prostate

DOI: 10.14670/HH-29.1093