Matsui S, Shiozaki H, Inoue M, Tamura S, Doki Y, Kadowaki T, Iwazawa T, Shimaya K, Nagafuchi A, Tsukita S
Department of Surgery II, Osaka University Medical School, Japan.
Virchows Arch. 1994;424(4):375-81. doi: 10.1007/BF00190559.
E-cadherin (E-cad) plays a major role in the maintenance of cell-cell adhesion in epithelial tissues, and impaired E-cad expression correlates with tumour invasion and metastasis. Alpha-catenin (alpha-cat), an undercoat protein of adherens junctions, binds to the cytoplasmic domain of E-cad and is essential for linking E-cad to actin-based cytoskeleton. We investigated E-cad and alpha-cat expression in 60 human gastric cancers immunohistochemically. The 60 gastric cancers were classified into 18 (30%) in which alpha-cat expression was preserved, and 42 (70%) reduced cases. The reduction of alpha-cat expression was significantly related to dedifferentiation, depth of invasion, infiltrative growth and lymph node metastasis. We also examined the co-expression of alpha-cat and E-cad. Seventeen (28%) tumours preserved both molecules [alpha-cat(+)/E-cad(+)] and 33 (55%) tumours reduced both [alpha-cat(-)/E-cad(-)], whereas 9 (15%) tumours exhibited alpha-cat(-)/E-cad(+). The frequency of lymph node metastasis in alpha-cat(-)/E-cad(+) tumour (67%) was significantly higher than that in alpha-cat(+)/E-cad(+) tumours (24%) and was close to that in alpha-cat(-)/E-cad(-) tumours (82%). The frequency of haematogenous liver metastasis in alpha-cat(-)/E-cad(+) tumours (44%) was significantly higher than that in alpha-cat(+)/E-cad(+) tumours (6%) or alpha-cat(-)/E-cad(-) tumours (9%). Thus, in all E-cad(+) tumours, the frequency of lymph node and liver metastasis was higher in alpha-cat(-) tumours than in alpha-cat(+) tumours. alpha-Cat expression is apparently better at predicting tumour invasion and metastasis than E-cad expression.
E-钙黏蛋白（E-cad）在上皮组织细胞间黏附的维持中起主要作用，E-cad表达受损与肿瘤侵袭和转移相关。α-连环蛋白（α-cat）是黏附连接的一种底层蛋白，与E-cad的胞质结构域结合，对于将E-cad连接到基于肌动蛋白的细胞骨架至关重要。我们采用免疫组织化学方法研究了60例人胃癌中E-cad和α-cat的表达。60例胃癌分为α-cat表达保留的18例（30%）和α-cat表达降低的42例（70%）。α-cat表达降低与去分化、浸润深度、浸润性生长和淋巴结转移显著相关。我们还检测了α-cat和E-cad的共表达情况。17例（28%）肿瘤两种分子均保留[α-cat(+)/E-cad(+)]，33例（55%）肿瘤两种分子均降低[α-cat(-)/E-cad(-)]，而9例（15%）肿瘤表现为α-cat(-)/E-cad(+)。α-cat(-)/E-cad(+)肿瘤的淋巴结转移频率（67%）显著高于α-cat(+)/E-cad(+)肿瘤（24%），且接近α-cat(-)/E-cad(-)肿瘤（82%）。α-cat(-)/E-cad(+)肿瘤的肝血行转移频率（44%）显著高于α-cat(+)/E-cad(+)肿瘤（6%）或α-cat(-)/E-cad(-)肿瘤（9%）。因此，在所有E-cad(+)肿瘤中，α-cat(-)肿瘤的淋巴结和肝转移频率高于α-cat(+)肿瘤。α-cat表达在预测肿瘤侵袭和转移方面显然优于E-cad表达。
