Dottorato in INGEGNERIA INDUSTRIALE E GESTIONALE

Titolo della tesi: Development of three innovative in-vitro systems to investigate cellular response in adherent cancer cells: mechanotransduction, elasticity and dielectric properties

Cells’ mechanical and electric properties, as well as cell mechanotransduction, are of fundamental importance in many healthy and pathological biological processes, including cell motility, adhesion, proliferation, morphology, and differentiation. In this context, the aim of this research project was to develop a series of novel experimental in-vitro systems for the study of cell mechanotransduction, cell elasticity and dielectric properties in adherent cancer cells. Nowadays, several devices are employed to recreate in-vitro mechanical loads, such as substrate deformation, shear stress and vertical vibrations in a controlled cell culture environment. On the other hand, adherent cells are also able to perceive mechanical feedback from the underneath matrix and convert it into biochemical signals, via mechanotransduction, even in the absence of externally applied forces. Various studies have reported that a stiffness-controlled substrate, generated to simulate different native tissues, significantly impacts cells’ behaviour. Moreover, cellular response to the microenvironment changes partly depends on their intrinsic properties, including cellular elasticity and dielectric characteristics, which have been recently proposed as biomarkers for the correlation of various human diseases. Understanding the relationship between cells’ mechanical and electric properties, and their response and adaptation to the continuous modifications of their surroundings are gaining increasing attention in cancer research and the development of non-invasive in-vitro systems for cellular response investigation is crucial to understand cell physiological and pathological functionality, to pave the way for innovative diagnostic and therapeutic applications. The following work is composed of three chapters, related to the three macro-themes concurring with the aims above described: cell mechanotransduction, cell elasticity, and cell dielectric properties. Chapter 1 is related to cell mechanotransduction, comprising the development of a custom-made uniaxial strain device to study cancer cell response to a combined mechanical load, namely an external substrate deformation and the cell underlying matrix stiffness. Chapter 2 is focused on the validation of a non-invasive optical method for cell elasticity measurement of cancer cell lines. Chapter 3 describes the development of a novel microwave biosensor, investigating its capability to discriminate different cancer cell types with different aggressiveness.