van den Brûle F A, Buicu C, Sobel M E, Liu F T, Castronovo V
Metastasis Research Laboratory, University of Liège, Belgium.
Neoplasma. 1995;42(5):215-9.
Galectin-3 is a laminin binding protein which expression is altered in a variety of human carcinomas including colon, breast and endometrium. In these tumors, we consistently observed a down regulation of galectin-3 expression related to increased aggressiveness. Galectin-3 belongs to a family of galactose-binding lectins and binds laminin through its numerous poly-N-acetyllactosamine chains. To date, the exact role of galectin-3 in the complex interactions between cancer cells and laminin has not been clearly defined. Adhesion of melanoma cells to laminin is a critical event during tumor invasion and metastasis. In this study, we explore the possibility that galectin-3 could modulate attachment of two human melanoma cell lines to laminin. A2058 and A375 melanoma cell expressed galectin-3 on their surface as demonstrated by immunofluorescence, and attached to laminin in an in vitro assay. We demonstrate that neither recombinant galectin-3 nor an affinity purified antigalectin-3 antiserum altered adhesion of A2058 or A375 melanoma cells to laminin. Our data strongly suggest that galectin-3 is not a key element in adhesion of the melanoma cells to laminin. These results are not surprising in light of the observation that galectin-3 expression is down regulated in cancer and that increased adhesion to laminin is a constant feature of invasive cancer cells.
半乳糖凝集素-3是一种层粘连蛋白结合蛋白，其表达在包括结肠癌、乳腺癌和子宫内膜癌在内的多种人类癌症中发生改变。在这些肿瘤中，我们一致观察到半乳糖凝集素-3表达下调与侵袭性增加有关。半乳糖凝集素-3属于半乳糖结合凝集素家族，通过其众多的多聚-N-乙酰乳糖胺链与层粘连蛋白结合。迄今为止，半乳糖凝集素-3在癌细胞与层粘连蛋白之间复杂相互作用中的确切作用尚未明确界定。黑色素瘤细胞与层粘连蛋白的黏附是肿瘤侵袭和转移过程中的一个关键事件。在本研究中，我们探讨了半乳糖凝集素-3调节两种人类黑色素瘤细胞系与层粘连蛋白黏附的可能性。免疫荧光显示，A2058和A375黑色素瘤细胞在其表面表达半乳糖凝集素-3，并在体外试验中与层粘连蛋白黏附。我们证明，重组半乳糖凝集素-3和亲和纯化的抗半乳糖凝集素-3抗血清均未改变A2058或A375黑色素瘤细胞与层粘连蛋白的黏附。我们的数据强烈表明，半乳糖凝集素-3不是黑色素瘤细胞与层粘连蛋白黏附中的关键因素。鉴于观察到癌症中半乳糖凝集素-3表达下调且侵袭性癌细胞与层粘连蛋白的黏附增加是一个恒定特征，这些结果并不令人惊讶。
