Development of microfluidic platforms for studies on colorectal cancer organoids in decellularized ECM-derived hydrogel

Microfluidics, a technology characterized by the manipulation of fluids at the submillimeter scale, has shown considerable promise for improving diagnostics and biology research. Certain properties of microfluidic technologies, such as rapid sample processing, the precise spatio-temporal control of fluids, and the reduction in volumes of reagents and biological materials, have made them attractive candidates to replace traditional experimental approaches. In particular, microfluidic devices can be used in applications that require the formation of a concentration gradient. The presence of gradients plays a fundamental role in many biological activities and regulates various cellular functions that occur within the human body. The design and the manipulation of such gradients is of increasing interest in the drug testing field. To obtain a better representation of pharmacokinetics and pharmacodynamics, it was decided to replace traditional 2D cell cultures with organoids. Organoids are cell complexes grown in 3D to form structural units and they can replicate the key structural and functional characteristics of the target organs in vivo. Traditional organoid technology has limitations, including lack of physical and chemical microenvironment control, high heterogeneity, complex manual operation and imperfect nutritional supply system. The combination of microfluidic chip technology and organoids has overcome many of these limitations and greatly expanded the scope of applications. In this thesis, the aim is to combine the advantages of microfluidics with the advantages of organoid technology, creating a device in which the organoids of colorectal cancer (CRC) grow embedded in a decellularized ECM-derived hydrogel. CRC usually originates from epithelial cells following well-defined pathogenic events. However, CRC could undergo modifications and proceed along different ways in terms of growth, aggressiveness and outcome. In this context, different studies on CRC demonstrated that the ECM is responsible of either containment of tumor growth or lead tumor progression with a poor prognosis. Considering the influence of the tumor ECM, the importance of a controlled environment is evident, and it is obtained through the union of microfluidic devices and the 3D matrix of the hydrogel. In this study, the material is produced from colon biopsies of healthy patients, and to better understand its mechanical properties, mechanical characterization was performed by FRAP analysis, swelling tests, rheology tests, and AFM.