title: Actin-based biomechanical features of suspended normal and cancer cells.
abstract: The mechanical features of individual cells have been regarded as unique indicators of their states, which could constantly change in accordance with cellular events and diseases. Particularly, cancer progression was characterized by the disruption and/or reorganization of actin filaments causing mechanical changes. Thus, mechanical characterization of cells could become an effective cytotechnological approach for early detection of cancer. To develop mechanical cytotechnology, it would be necessary to clarify the mechanical properties in various cell adhesion states. In this study, we investigated the surface mechanical behavior of cancer and normal cells in the adherent and suspended states using atomic force microscopy. Adherent normal stromal cells showed high surface stiffness due to developed actin cap structures on their apical surface, whereas cancer cells did not have developed filamentous actin structures, and their surface stiffness was low. Upon cell detachment from the substrate, filamentous actin structures of adherent normal stromal cells reorganized to the cortical region and their surface stiffness decreased consequently however, the stiffness of suspended normal cells remained higher than that of cancer cells. These suspended state actin structures were similar, regardless of the cell type. Furthermore, the mechanical responses of the cancer and normal stromal cells to perturbation of the actin cytoskeleton were different, suggesting distinct regulatory mechanisms for actin cytoskeleton in cancer and normal cells in both adherent and suspended states. Therefore, cancer cells possess specific mechanical and actin cytoskeleton features different from normal stromal cells.
authors.affiliation: Department of Mechanical Science and Bioengineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan.
authors.forename: Seyed Mohammad Ali
authors.initials: SM
authors.lastname: Haghparast
authors.forename: Takanori
authors.initials: T
authors.lastname: Kihara
authors.forename: Yuji
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Yuba
authors.forename: Jun
authors.initials: J
authors.lastname: Miyake
mesh_terms: D000199:Actins / Q000378:metabolism*; D000818:Animals; D001696:Biomechanical Phenomena; D002448:Cell Adhesion; D002460:Cell Line; D045744:Cell Line, Tumor; D003599:Cytoskeleton / Q000378:metabolism; D006801:Humans; D008297:Male; D018625:Microscopy, Atomic Force; D009369:Neoplasms / Q000473:pathology*; D051381:Rats; D011916:Rats, Inbred F344; D017154:Stromal Cells / Q000166:cytology*
chemical_list: D000199:Actins
keywords: Actin cytoskeleton; Atomic force microscopy; Cancer cell; Mechanical cytotechnology; Mechanical features; Suspended state