Studying the Local Young's Modulus of PC-3 Cells Via Scanning Ion-Conductance Microscopy

Abstract

Stiffness measurement of single cell via Scanning Ion-conductance Microscopy (SICM) is a novel method of studying cell mechanical properties. Due to the work principle of SICM, which is allow to topography mapping with lateral and vertical nanoscale resolution. Also, it's possible to provide simultaneously stiffness mapping, due to applying low stress on cell surface, whose nature is intrinsic colloidal pressure between nanopipette tip and cell membrane. Nanoscale diameter of nanopipette tip allows to obtain cell stiffness distribution on different parts of single cell. We report cell stiffness measurement of drug-induced alterations in cancer cell compartments studied by SICM, specifically, we measured fibrosarcoma cells (HT1080) transfectioned with Progerin, which is integrate in protein structure of nucleus membrane. Progerin was modified with GFP fluorescence dye (GFP-Progerin). Also, we provided stiffness measurement on PC3 and HT1080 cells exposed to paclitaxel and monomethyl auristatin for stabilization and depolymerization of microtubules, respectively, as well as cytochalazin-d for depolymerization of actin filaments. Experiments with GFP-Progerin were provided in heterogeneous population of HT1080 with control and GFP-Progerin transfectioned cells. Control cell stiffness measurement shows 1.7kPa and 0.7kPa, when GFP-Progerin treated cells increased value only on nucleus area. In control and treated PC3 and HT1080 cells we measured cell stiffness upon the nucleus area and cytoplasm area, which are show two different values in control cells. Measured stiffness after Paclitaxel treatment shows significantly increased stiffness value on nucleus area and cytoplasm area, whereas monomethyl auristatin shows reverse effect for both cell lines, as well as after cytochalasin-d. SICM research was funded by Ministry of Education and Science of the Russian Federation implemented by a governmental decree dated 16 March 2013, no. 211. The biological experiments were funded by Russian Science Foundation, grant number no 20-14-00312.