title: Increased expression of galectin-1 in carcinoma-associated stroma predicts poor outcome in prostate carcinoma patients.
abstract: Galectin-1, a member of the beta-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, p<0.0001). Increased galectin-1 expression in the cancer-associated stroma compared to the normal gland-associated stroma (p=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.
authors.affiliation: Metastasis Research Laboratory, University Hospital, University of Liège, B-4000 Liège 1, Belgium. f.vandenbrule@chu.ulg.ac.be
authors.forename: F A
authors.initials: FA
authors.lastname: van den Brûle
authors.forename: D
authors.initials: D
authors.lastname: Waltregny
authors.forename: V
authors.initials: V
authors.lastname: Castronovo
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism*; D015153:Blotting, Western; D018450:Disease Progression; D018572:Disease-Free Survival; D005500:Follow-Up Studies; D037483:Galectin 1; D006388:Hemagglutinins / Q000378:metabolism*; D006801:Humans; D007124:Immunoenzyme Techniques; D037102:Lectins / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism*; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000378:metabolism; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D017154:Stromal Cells / Q000378:metabolism; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D037483:Galectin 1; D006388:Hemagglutinins; D037102:Lectins; D009363:Neoplasm Proteins; D017430:Prostate-Specific Antigen