Electric-field assisted tunneling nanotube formation between cancer cells in a microfluidic device
Huei-Jyuan Pan (潘慧娟)1*, Zheng-Ting Wei (魏政霆)2, Chia-Wei Lee (李家瑋)1, Hsin-Ying Han (韓欣穎)3, Chia-Ning Shen (沈家寧)3, Chau-Hwang Lee (李超煌)1,2,4
1Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
2Institute of Biophotonics, National Yang-Ming University, Taipei, Taiwan
3Genomics Research Center, Academia Sinica, Taipei, Taiwan
4Department of Physics, National Taiwan University, Taipei, Taiwan
* presenting author:Huei-Jyuan Pan, email:cathypanhj@hotmail.com
Tumor–stromal interactions affect various responses of cancer cells, including proliferation, invasion, immune tolerance, epithelial–mesenchymal transition (EMT), etc [1]. Tunneling nanotubes (TNTs) were recognized as a special cellular structure for long-distance cell–cell communication [2]. Various substances can be transported from one cell to the other through TNTs, including proteins, microRNAs, intracellular vesicles, mitochondria, etc [3]. Therefore, the formation and functions of TNTs are important subjects for understanding tumor growth and invasion in tumor microenvironment.
In this work we used a microfluidic cell culture device capable of building a stable direct-current electrical field (dcEF) to facilitate the formation of TNTs between two cancer cells. We found that the pancreatic cancer cell BxPC-3 exhibits anodal electrotaxis in a dcEF, and during the cells separating from each other, the macrophage conditioned medium (MaCM) could stimulate the TNT formation between two cancer cells. We also found that the BxPC3 cells underwent EMT with the MaCM treatment. These results implicated that TNTs are possibly participated in tumor progression.

Referecnes
1. H. G. Zhang and W. E. Grizzlet, Am. J. Pathol. 184, 28 (2014).
2. A. Rustom, R. Saffrich, I. Markovic, P. Walther, and H. H. Gerdes, Science 303, 1007 (2004).
3. S. Sisakhtnezhad and L. Khosravi, Eur. J. Cell Biol. 94, 429 (2015).



Keywords: electrotaxis, tunneling nanotube, cell–cell communication