Influence on Cancer Cell Activities by Myo-fibroblasts Experiencing Cyclic Tensile Stretch

• Main Authors: Jiun-Wei Huang, 黃俊惟
• Other Authors: Chih-Wei Wu
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/33732278650665878338

碩士 === 國立臺灣海洋大學 === 機械與機電工程學系 === 100 === In the tumor microenvironment, the interactions between cancer cells and surrounding stromal cells could increase the proliferation and migration of cancer cells. The phenotype of cancer-associated fibroblast is close to myofibroblast (MF), which plays important roles in the development and metastasis of tumors by exchanging major growth factors with cancer cells. Fibroblasts are known to be activated to MFs by transforming growth factor 1 (TGF-1), but some literatures indicate that this process is also mediated by mechanical tension. This research is focused on lung cancer cells and lung MFs because the cytoskeletons of lung MFs keeps experiencing cyclic tensile strain (CTS) during breathing. Therefore, it is interesting to understand the effects of physical (cyclic stretching) and chemical (interleukin-1) stimulations on cancer cell migration by mediating the activities of MFs. In this work, we designed a two-layer polydimethylsiloxane (PDMS) microfluidic cell-culture chip to introduce cyclic tensile stretch (CTS) on culture chamber of MFs. The cell lines used in this experiment were human lung cancer cells (CL1-0) and lung fibroblasts (MRC-5). The fibroblasts were activated by TGF-1 and then the activation was confirmed by quantifying the-smooth muscle actin (-SMA), a major marker of MFs, by fluorescence images. Then, in order to simulate the normal breathing cycle, we employed 0.27 Hz, 10% CTS on the MFs for 6 hours and let the conditioned medium of MFs flow to the culture chamber of cancer cells simultaneously. The average migration speed was calculated from the displacement of cell centroids in the 6 hours. On the other hand, interleukin -1 (IL-1 can enhance activities of MFs, but the effects of IL-1on MFs under CTS are unclear. By using this chip, the MFs were treated with physical and chemical stimulations and we can observe two types of cells at the same time. The results show that the conditioned medium of MFs effectively increases the cancer cells motility, while the CTS significantly reduces the activity of MFs to enhance the migration speed of cancer cells. However, IL-1 can enhance the ability of MFs to resist the effect of CTS.