Scanning electron microscopy with an ionic liquid reveals the loss of mitotic protrusions of cells during the epithelial-mesenchymal transition

• Published in: Microscopy research and technique 2011-11, Vol.74 (11), p.1024-1031
• Main Authors: Ishigaki, Yasuhito, Nakamura, Yuka, Takehara, Teruaki, Shimasaki, Takeo, Tatsuno, Takanori, Takano, Fumihide, Ueda, Yoshimichi, Motoo, Yoshiharu, Takegami, Tsutomu, Nakagawa, Hideaki, Kuwabata, Susumu, Nemoto, Noriko, Tomosugi, Naohisa, Miyazawa, Shichiro
• Format: Article
• Language: English
• Subjects: A549; Cadherins - analysis; Cell Line, Tumor; Epithelial Cells - chemistry; Epithelial Cells - drug effects; Epithelial Cells - ultrastructure; Epithelial-Mesenchymal Transition; Growth factors; Human; Humans; Inducers; ionic liquid; Ionic liquids; Ionic Liquids - metabolism; Markers; Microscopy; Microscopy, Electron, Scanning - methods; Microscopy, Fluorescence; Panc-1; Proteins; Pseudopodia - drug effects; Pseudopodia - ultrastructure; Scanning electron microscopy; SEM; TGF-β1; Transforming Growth Factor beta1 - metabolism; Vimentin - analysis
• ISSN: 1059-910X; 1097-0029; 1097-0029
• DOI: 10.1002/jemt.20989

Epithelial–mesenchymal transition (EMT) is a key event in cancer metastasis and is characterized by increase in cell motility, increase in expression of mesenchymal cell markers, loss of proteins from cell‐to‐cell junction complexes, and changes in cell morphology. Here, the morphological effects of a representative EMT inducer, transforming growth factor (TGF)‐β1, were investigated in human lung adenocarcinoma (A549) cells and pancreatic carcinoma (Panc‐1) cells. TGF‐β1 caused morphological changes characteristic of EMT, and immunostaining showed loss of E‐cadherin from cell‐to‐cell junction complexes in addition to the upregulation of the mesenchymal marker vimentin. During scanning electron microscopy (SEM) with an ionic liquid, we observed EMT‐specific morphological changes, including the formation of various cell protrusions. Interestingly, filopodia in mitotic cells were clearly observed by SEM, and the number of these filopodia in TFG‐β1‐treated mitotic cells was reduced significantly. We conclude that this reduction in such mitotic protrusions is a novel effect of TGF‐β1 and may contribute to EMT. Microsc. Res. Tech., 2011. © 2011 Wiley Periodicals, Inc.