Castronovo V, Van Den Brûle F A, Jackers P, Clausse N, Liu F T, Gillet C, Sobel M E
Laboratory of Pathology, National Cancer Institute, Bethesda, MD 20892, USA.
J Pathol. 1996 May;179(1):43-8. doi: 10.1002/(SICI)1096-9896(199605)179:1<43::AID-PATH541>3.0.CO;2-N.
Galectin-3, a member of the beta-galactoside-binding lectin family, is involved in several biological events including binding to the basement membrane glycoprotein laminin. Although the exact role of galectin-3 during the interactions between cells and laminin is not yet known, it has recently been observed that its expression is down-regulated at both the protein and the mRNA level in colon cancer tissues in correlation with progression of the disease. This study investigated the possibility that breast cancer cells might also exhibit decreased galectin-3 expression in association with their aggressiveness. The expression of galectin-3 was examined by immunoperoxidase staining, using a polyclonal antibody raised against recombinant galectin-3, in a collection of 98 human breast lesions including 12 fibroadenomas, 15 fibrocystic disease lesions, 22 in situ carcinomas, and 49 infiltrating ductal carcinomas, 19 of which had positive axillary lymph nodes. Normal breast tissue adjacent to the lesions was present in 59 biopsies. Normal breast tissue expressed high levels (3+) of galectin-3. High expression (2+ to 3+) was also found in most benign lesions examined. The expression of galectin-3 was significantly decreased in in situ carcinoma and this down-regulation was more pronounced in invasive ductal carcinoma, particularly when associated with infiltration of axillary lymph nodes. These data constitute the first observation that galectin-3 is down-regulated in breast cancer and suggest the decreased expression of this galactoside-binding lectin is associated with the acquisition of the invasive and metastatic phenotype.
半乳糖凝集素-3是β-半乳糖苷结合凝集素家族的一员，参与多种生物学事件，包括与基底膜糖蛋白层粘连蛋白结合。尽管半乳糖凝集素-3在细胞与层粘连蛋白相互作用过程中的确切作用尚不清楚，但最近观察到，在结肠癌组织中，其蛋白和mRNA水平的表达均与疾病进展相关而下调。本研究调查了乳腺癌细胞是否也可能因其侵袭性而表现出半乳糖凝集素-3表达降低的可能性。使用针对重组半乳糖凝集素-3产生的多克隆抗体，通过免疫过氧化物酶染色检测了98例人类乳腺病变中的半乳糖凝集素-3表达，这些病变包括12例纤维腺瘤、15例纤维囊性疾病病变、22例原位癌和49例浸润性导管癌，其中19例有腋窝淋巴结转移。59例活检中有与病变相邻的正常乳腺组织。正常乳腺组织表达高水平（3+）的半乳糖凝集素-3。在大多数检测的良性病变中也发现了高表达（2+至3+）。半乳糖凝集素-3的表达在原位癌中显著降低，这种下调在浸润性导管癌中更明显，尤其是与腋窝淋巴结转移相关时。这些数据首次观察到乳腺癌中半乳糖凝集素-3下调，并表明这种半乳糖苷结合凝集素表达降低与侵袭性和转移表型的获得有关。
