Increased expression of galectin-1 in carcinoma-associated stroma predicts poor outcome in prostate carcinoma patients

Publisher Website
Google Scholar
Abstract
Galectin‐1, a member of the β‐galactoside‐binding galectin family, is a pleiotropic dimeric protein participating in a variety of normal and pathological processes, including cancer progression. Modulation of the interactions with the basement membrane glycoprotein laminin and induction of apoptosis in activated T lymphocytes are well‐known functions of this galectin. In this study, the expression of galectin‐1 was examined in 148 human primary prostate carcinoma samples. Immunohistochemical staining of paraffin sections of prostate tissues revealed that galectin‐1 was not detected in normal, PIN (prostatic intraepithelial neoplasia) or carcinoma cells, but accumulated in the stroma and associated fibroblasts. Galectin‐1 expression was significantly increased in the tumour‐associated stroma compared with the non‐neoplastic gland‐associated stroma in 21.3% of the cases (Mantel–Haenszel test, p=0.001; Wilcoxon signed rank test, pp=0.03) was identified by multivariate analysis as a strong independent predictor of prostate‐specific antigen (PSA) recurrence, just after the pathological stage (p<0.0001). The association between accumulation of galectin‐1 in the stroma of the malignant tissue and aggressiveness of the tumour adds weight to the body of evidence that identifies a role for galectin‐1 in the acquisition of the invasive phenotype. In addition to modulating cancer cell interactions with laminin, galectin‐1 accumulated around the cancer cells may act as an immunological shield by inducing activated T‐cell apoptosis. This exciting hypothesis warrants further investigation. Copyright © 2000 John Wiley & Sons, Ltd.