Dynamic Characterization of Human Breast Cancer Cells Using a Piezoresistive Microcantilever

Abstract

In this paper, frequency response (dynamic compression and recovery) is suggested as a new physical marker to differentiate between breast cancer cells (MCF7) and normal cells (MCF10A). A single cell is placed on the laminated piezoelectric actuator and a piezoresistive microcantilever is placed on the upper surface of the cell at a specified preload displacement (or an equivalent force). The piezoelectric actuator excites the single cell in a sinusoidal fashion and its dynamic deformation is then evaluated from the displacement converted by measuring the voltage output through a piezoresistor in the microcantilever. The microcantilever has a flat contact surface with no sharp tip, making it possible to measure the overall properties of the cell rather than the local properties. These results indicate that the MCF7 cells are more deformable in quasi-static conditions compared with MCF10A cells, consistent with known characteristics. Under conditions of high frequency of over 50 Hz at a 1 μm preload displacement, 1 Hz at a 2 μm preload displacement, and all frequency ranges tested at a 3 μm preload displacement, MCF7 cells showed smaller deformation than MCF10A cells. MCF7 cells have higher absorption than MCF10A cells such that MCF7 cells appear to have higher deformability according to increasing frequency. Moreover, larger preload and higher frequencies are shown to enhance the differences in cell deformability between the MCF7 cells and MCF10A cells, which can be used as a physical marker for differentiating between MCF10A cells and MCF7 cells, even for high-speed screening devices.

Cytoskeletal stiffness, friction, and fluidity of cancer cell lines with different metastatic potential

“…Thus, biophysical differences between strongly and weakly metastatic cancer cells may emerge only under large forces and deformations. Metastatic and non-metastatic breast cancer cells subjected to a small oscillatory deformation superimposed over an initial stretch using piezoresistive microcantilevers showed differences in deformability that were dependent magnitude of the initially stretch [66]. At low initial stretch, metastatic cells were more deformable than nonmetastatic cells at low frequencies.…”

“…Previous efforts to relate metastatic ability to cancer cell biophysics focused almost exclusively on measures of deformability [28, 54, 63, 66–70]. Early approaches combined animal models of cancer development with in vitro biophysical assessment to investigate the role of cancer cell deformability on cancer progression.…”

“…Subsequent studies eschewed the use of animal models to instead assess metastatic ability of human tumor cell lines whose metastatic potential was inferred from their tissue of origin. In a well-characterized model system, non-metastatic MCF-7 breast ductal carcinoma cells were more deformable than normal MCF10A breast mammary epithelial cells whether suspended [67, 68, 72] or adherent [64, 66, 73, 74] with the exception of one study reporting the opposite finding [75]. Further, chemically or genetically increased invasive ability further increased deformability [67, 68, 72, 73].…”

Characterization of Dynamic Behaviour of MCF7 and MCF10A Cells in Ultrasonic Field Using Modal and Harmonic Analyses

“…Dynamic modelling and FEM analysis were used to determine the Young’s modulus of the cell wall of yeast cells using their known resonance frequency [ 24 ]. The method of frequency response (dynamic compression and recovery) using a piezoelectric actuator which excites a single cell in sinusoidal fashion was suggested as a new physical marker to differentiate the human breast cancer MCF7 cells from normal MCF10A human breast cells [ 25 , 26 ]. Frequency and preload-dependent differences were found in the deformability of both cell types.…”

Discrimination between the human prostate normal cell and cancer cell by using a novel electrical impedance spectroscopy controlling the cross-sectional area of a microfluidic channel

“…8 Diagnostic methods using the electrical characteristics of cells have proven to be cost effective, much faster, and less invasive than mechanical measurement techniques. 9 Approaches based on electrical impedance can also replace general biochemistry-based diagnostics. Electrical impedance spectroscopy (EIS) is an analytic tool that is widely known as a detection method for electrical properties of tissues or cells in the frequency domain.…”