細胞外基質(extracellular matrix, ECM)能提供網狀結構有利於細胞貼附、組織及器官的形成。而整合素(integrin)是細胞膜上的受體可與細胞外基質結合且決定細胞貼附、移動、生長、增殖及生存之能力。過去研究發現整合素與細胞外基質結合能影響細胞內信號(intracellular signals)促進細胞骨架的形成或產生各種細胞反應。但很少有研究再探討細胞生長於細胞外基質上的細胞力學(cell mechanics)反應，因此我們假設細胞生長於細胞外基質藉由細胞骨架的連接聚集，能增強細胞力學之表現。
　　因此選用了原子力顯微鏡(atomic force microscopy, AFM)可以細胞正常生理環境下量測且具有高解析度的優點，取得細胞形貌並配合赫茲接觸理論來計算細胞機械性質。量測人類子宮頸癌細胞(cervical cancer CaSki cell)生長於不同的環境下，發現細胞生長在纖維連接蛋白(fibronectin)鑲嵌(25 μg/ml)之培養皿有較強的韌性(0.61 kPa)，而生長在一般培養皿則韌性較低(0.39 kPa)。進一步利用免疫螢光染色觀察細胞骨架和focal adhesion size，發現focal adhesion size在鑲嵌25 μg/ml纖維連接蛋白時達到飽和大小(1.44 μm2)，肌動蛋白(actin)呈現coiled-coil型態，證實細胞外基質能促進細胞貼附降低細胞移動。

　　The extracellular matrix (ECM) provides the structural framework for the formation of tissues and organs. Integrin is a cell surface receptor that integrin-matrix interactions determine cell adhesion, motility, growth, proliferation, and survival. Previous studies found that integrin-matrix interactions influence cell differentiation and commitment, as well as intracellular signals, promote cytoskeleton formation and cell responses. Only very few studies have addressed the cell mechanics of cell-ECM complex interactions. Thus, our hypothesis is that the cell growth with ECM enhances the connection of cytoskeletons, results in stronger cell mechanics behavior.
　　Aiming to verify this hypothesis, we need to get the information of cell shape and mechanical properties. The atomic force microscopy (AFM) has high resolution to image living cells in similarly physiology environment and can be used to evaluate mechanical properties of cells by using Hertz contact theory. In this study, we compared the human cervical cancer CaSki cell growth with different environments, then found that overall cell stiffness of cells growth in 25 μg/ml fibronectin-coated dish (0.61 kPa) higher than growth in bare dish (0.39 kPa). Furthermore, immunofluorescent method was also employed to observe the focal adhesion size (FA size) and cytoskeleton, found that the maximum of FA size was on 25 μg/ml fibronectin-coated dish, and actin was coiled-coil fiber. According to immunofluorescent, prove that ECM promotes cell adhesion and reduces migration.

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