Fukuyama R, Minoshima S, Ochiai A, Tahara E, Shimizu N
Department of Molecular Biology, Keio University School of Medicine, Tokyo, Japan.
Int J Cancer. 1991 Apr 22;48(1):81-4. doi: 10.1002/ijc.2910480115.
We have previously produced a monoclonal antibody (MAb) against TMK-1 cells, a poorly differentiated stomach-cancer cell line, and designated the antigen as 9A3. Immunohistochemical analysis of various tumor tissues revealed that the expression of 9A3 antigen is specific for human adenocarcinoma. In the present study, we analyzed the expression patterns of 9A3 antigen on TMK-1 cells and compared them with the expression patterns of E-cadherin and epidermal-growth-factor (EGF) receptors, using immunofluorescent microscopy and flow cytometry. The flow cytometric analysis revealed that the TMK-1 cell population consists of 9A3-positive cells and 9A3-negative cells. The isolated 9A3-negative cell population generates 9A3-positive cells as they divide, whereas the isolated 9A3-positive cell population does not generate 9A3-negative cells. The 9A3-positive cells grow as tight colonies, whereas the 9A3-negative cell form loose colonies in soft agar culture. E-cadherin was expressed only in the 9A3-positive TMK-1 cells and not in the 9A3-negative cells. In contrast, EGF receptor was expressed in both cell populations. The 9A3 antigen was localized mainly at the cell-cell adhesion sites where E-cadherin was apparently condensed.
我们之前制备了一种针对TMK-1细胞（一种低分化胃癌细胞系）的单克隆抗体（MAb），并将该抗原命名为9A3。对各种肿瘤组织的免疫组织化学分析显示，9A3抗原的表达对人腺癌具有特异性。在本研究中，我们使用免疫荧光显微镜和流式细胞术分析了9A3抗原在TMK-1细胞上的表达模式，并将其与E-钙黏蛋白和表皮生长因子（EGF）受体的表达模式进行了比较。流式细胞术分析显示，TMK-1细胞群体由9A3阳性细胞和9A3阴性细胞组成。分离出的9A3阴性细胞群体在分裂时会产生9A3阳性细胞，而分离出的9A3阳性细胞群体不会产生9A3阴性细胞。9A3阳性细胞紧密聚集生长，而9A3阴性细胞在软琼脂培养中形成松散的集落。E-钙黏蛋白仅在9A3阳性的TMK-1细胞中表达，而在9A3阴性细胞中不表达。相反，EGF受体在两个细胞群体中均有表达。9A3抗原主要定位于E-钙黏蛋白明显浓缩的细胞间黏附部位。
