Modulation of Cell-Cell Adhesion by Integrin Signals in Oral Squamous Carcinoma Cells

口腔鳞状细胞癌细胞中整合素信号对细胞间粘附的调节

• 批准号: 11671997
• 负责人: KAWANO Kenji
• 金额: $ 2.24万
• 依托单位: 大分医科大学
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11671997/
• 关键词: Oral squaumous cell carcinoma; Cell-cell adhesion; Cell scattering; Extracellular matrix; E-cadherin; β catenin; α3β1 integrin; Laminin5; Eカドヘリン; カドヘリン; カテニン; インテグリン; 細胞外基質タンパク

When cultured in the non-adherent dish coated with poly-HEMA, oral squamous carcinoma cells, MOK101, formed multicellular aggregates (MCA). In this process, the amount of E-cadherin in MCAs increased as MCAs became compact. Since the formation of MCAs was delayed by the existence of anti-E-cadherin inhibitory antibody, the cell-cell adhesion mediated by E-cadherin was important in the formation of MCAs. When MCAs were seeded on laminin 5 rich matrix and type I collagen, MCAs rearranged to monolayer colonies on both substrates. However, cell dissociation was observed only on laminin 5, but not on type I collagen. By western blotting analysis, the cell-scattering on laminin 5 was associated with the increase of β catenin in 0.2 % Triton X-100 soluble fraction, and tyrosine phosphorylation of β catenin was detected in scattering cells on laminin 5. Furthermore, antibodies against α3 and β1 integrin subunits blocked the cellscattering on laminin 5, while α2 and α6 integrin antibodies did not, suggesting that the in-out signal via α3β1 integrin was predominantly involved in this phenomenon. Finally, we tested if the activation of α3 or β1 integrin subunit could trigger the collapse of MCAs by cross-linking of these integrins on the surface of MCAs. A few microspikes, which was also observed during the rearrangement of MCAs on laminin 5, were formed on the surface of MCAs, although MCAs failed to be broken down.These results suggest that integrin signals are concerned in the modulation of cell-cell adhesion in oral squamous carcinoma cells. However, the involvement of growth factors and increased cellular motility in the dissociation of MCAs on laminin 5 remains to be clarified.

口腔鳞癌细胞MOK 101在poly-HEMA包被的非贴壁培养皿中培养时，形成多细胞聚集体（MCA）。在此过程中，E-cadherin在MCA中的含量随着MCA的致密化而增加。由于抗E-cadherin抑制抗体的存在延缓了MCA的形成，因此E-cadherin介导的细胞间粘附在MCA的形成中起重要作用。当MCA接种在富含层粘连蛋白5的基质和I型胶原上时，MCA在两种基质上重排为单层集落。然而，仅在层粘连蛋白5上观察到细胞解离，而在I型胶原上未观察到。通过Western印迹分析，层粘连蛋白5上的细胞散射与0.2%Triton X-100可溶性组分中β连环蛋白的增加相关，并且在层粘连蛋白5上的散射细胞中检测到β连环蛋白的酪氨酸磷酸化。此外，针对α 3和β 1整合素亚基的抗体阻断了层粘连蛋白5上的细胞散射，而α 2和α 6整合素抗体则没有，这表明通过α 3 β 1整合素的进出信号主要参与了这种现象。最后，我们测试了α 3或β 1整合素亚基的活化是否可以通过这些整合素在MCA表面上的交联来触发MCA的塌陷。在MCAs的表面形成了一些微刺，这些微刺在MCAs在层粘连蛋白5上重排时也被观察到，但MCAs没有被分解。然而，生长因子的参与和增加的细胞运动性在层粘连蛋白5上的MCAs的解离仍有待澄清。