惡性腫瘤，也稱為癌症，蟬聯台灣十大死因之首，學術界近年來也致力於腫瘤的研究。其中良性與惡性腫瘤的差異就在於細胞轉移的有無，一旦癌細胞轉移到人體其他組織及器官後，整個療程將變得複雜且難以掌控，甚至急速惡化終結病人的生命。因此如何有效阻止癌細胞轉移，也是現階段癌症研究的主要目標。目前常用於研究細胞遷移(cell migration)的方法如transwell assay或wound healing assay已行之有年，但這類方法都有著缺點，像是需要較長的時間才能取得實驗數據，且不適用於高通量的實驗；更重要的是，這些傳統方法沒辦法有效地觀察到細胞在組織間轉移的變形瞬間。因此本實驗室近期致力於研發一系列具有顯微柱狀結構的PDMS晶片，該晶片能以更快速、低成本、易操作的方式，更有效地取得癌細胞及細胞核變形量的數據，並且在製備晶片的過程中我們還加入了PEG-BCP此劑來大幅提高PDMS晶片的親水性，減少晶片因疏水性產生氣泡而堵住顯微柱狀結構的現象。由於微流道中的顯微柱狀結構之間的狹縫比癌細胞還更小，因此當癌細胞流過這些狹縫時需產生形變(deformation)才得以穿越這些顯微柱狀結構。我們將細胞核進行專一性螢光染色之後，可以在顯微鏡下清楚捕捉到細胞核在顯微柱狀結構中的變形瞬間，並加以分析細胞的變形量。我們的實驗中會用TGF-β培養癌細胞以及基因轉染方式來調控細胞核的合纖層(lamin)，使得細胞核的軟硬度改變，再將細胞放入我們的PDMS微流道晶片來分析不同調控方式下，細胞核的變形量。在本研究中，我們得到控制組細胞株的整個細胞和細胞核的變形率(整個細胞= 3.84，細胞核= 1.76)，在不萃取細胞核進行實驗的情況下，細胞核的變形率相對較整顆細胞還小。細胞經過TGF-β培養後，比起控制組花費更長的時間才能通過顯微柱狀結構(控制組= 0.63秒, TGF-β = 4.73秒) ，但是當我們試圖以萃取出的細胞核獨立進行變形率研究時，我們當前的晶片設計無法有效捕捉到細胞核非常快速的變形瞬間。因此未來我們會持續設計不同大小的顯微通道進行實驗，做出最理想的PDMS檢測晶片，或是以一項新的研究方法持續研究癌症細胞核的變形率。

Malignant tumors, also known as cancer, are the top ten causes of death in Taiwan. To understand the mechanisms and treatments of cancer, tremendous efforts have been devoted into the tumor research over the past decades. The difference between benign and malignant tumors lies in the presence or absence of cell metastases. Once cancer cells metastasize to other tissues and organs of the human body, the patient’s health will deteriorate and the entire course of treatment will become complicated and difficult to control. Therefore, effectively preventing cancer cell metastasis is a main goal of cancer research. At present, methods commonly used to study cell migration, such as transwell assay or wound healing assay, have been used for many years, but these methods have disadvantages, such as taking a long time to obtain experimental data and not being suitable for high-throughput experiments. More importantly, these conventional methods cannot effectively monitor the deformation process of cancer cells as well as the cell nucleus. To solve the unmet need, a series of PDMS microchips with micro-pillar structures were developed to monitor the deformation of cancer cells and their nucleus in a faster, lower-cost, and easier-to-operate manner. In fabrication of the PDMS microchips, we added PEG-BCP to improve the hydrophilicity of the microchannels and reduce the generation of bubbles. Because the gaps between the micro-pillars in the microchannel were smaller than the cancer cells, the cancer cells apparently deformed to pass through the micro-pillars. By staining the nucleus with LCS1 we recorded the instantaneous deformation of the nucleus in the micro-pillars under the microscope and used it for analyzing the deformation rate of the cell. In our experiment, we used TGF-β to culture cancer cells and gene transfection to regulate the lamin of the nucleus, so as to change the softness and hardness of the nucleus, and then put the cells into our PDMS microchips to analyze the amount of deformation of the nucleus under different regulation methods. In this study, we obtained the deformation rate of the whole cell and nucleus of the control group cell line (whole cell = 3.84, nucleus = 1.76), and the deformation rate of the nucleus is relatively lower than that of the whole cell. Cells cultured with TGF-β took longer to pass through the micro-pillar structures than the controls (control group = 0.63 s, TGF-β = 4.73 s), but when we tried to extract the nuclei from the whole cells to further study the deformation rate, our current design of the microchip cannot effectively capture the rapid deformation moments of the nucleus. In the future, we will continue to design different sizes of gaps forming from the micro-pillars to make the most ideal PDMS detection chip or continue to study the deformation rate of cancer cell nuclei with a new research method.

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