Apoptosis induced by inhibition of intercellular contact.
Apoptosis induced by inhibition of intercellular contact.
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DOI：
10.1083/jcb.125.2.403
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发表时间：
1994-04
期刊：
影响因子：
--
通讯作者：
Burns GF
中科院分区：
文献类型：
--
作者：
Bates RC;Buret A;van Helden DF;Horton MA;Burns GF
LIM 1863结肠癌细胞系在中央管腔周围生长为杯状和柱状细胞的结构有机体，为正常结肠干细胞的发育提供了一个模型。从培养液中去除钙可以破坏类有机结构，导致单细胞悬浮。在钙离子重新注入后，细胞在24小时内改造类器官结构，对改造细胞的超微结构检查表明，这涉及一个复杂的过程，我们称之为紧握。为了确定参与类器官形成的黏附分子，我们试图通过在单抗存在下重新接种LIM 1863的单细胞悬液来阻断这一过程。针对αv亚基上构象表位的抗整合素抗体完全抑制了类有机物的重塑。由于这种细胞接触的抑制，结肠癌细胞迅速发生了凋亡。对所涉及的凋亡途径的研究表明，由于接触抑制细胞开始凋亡，导致68-和72-kD蛋白合成特异性增加。此外，细胞胞浆和细胞核提取液的免疫印迹显示，在诱导细胞凋亡时，抑癌基因产物P53迅速移位到细胞核。这些结果表明，细胞间的黏附可能是肿瘤细胞通过失去黏附分子或功能性P53蛋白而克服的结肠发育的重要调节因素。
The LIM 1863 colon carcinoma cell line grows as structural organoids of goblet and columnar cells around a central lumen and provides a model for the development of stem cells in the normal colon. The organoid structure can be disrupted by removal of calcium from the medium, resulting in a suspension of single cells. Upon readdition of calcium, the cells reform the organoid structure over a period of 24 h, and ultrastructural examination of the reforming cells reveals that this involves a complex process that we have termed clutching. To determine the adhesion molecules involved in organoid formation we attempted to block this process by single cell suspensions of LIM 1863 reseeded in the presence of monoclonal antibodies. An anti-integrin antibody directed against a conformational epitope on the alpha v subunit totally inhibited organoid reformation. As a consequence of this inhibition of cell contact the colon carcinoma cells rapidly underwent apoptosis. Investigations of the apoptotic pathway involved suggested an induction mechanism since the onset of apoptosis in the contact- inhibited cells showed specific increased synthesis of 68- and 72-kD proteins. In addition, immunoblotting of cytosolic and nuclear extracts of the cells revealed the rapid translocation of the tumor suppressor gene product, p53 to the cell nucleus upon induction of apoptosis. These results suggest that cell-cell adhesion may be a vital regulator of colon development overcome in tumor cells by loss of adhesion molecules or of functional p53 protein.