Development of organ-on-chip device for modeling the progression of cancer
Abstract
Organ-on-chip devices are advanced engineered microfluidic systems that replicate human organ functions on a small scale. They utilize living cells from human tissues and combine them with biomaterials to create a dynamic environment, mimicking the architecture and functionality of specific tissues to study organ responses in real-time. By exploring a more accurate representation of human biology compared to traditional cell culture methods, organ-on-chip technology holds promise for drug development, disease modelling, and personalized medicine. It can lead to more effective treatments and reduce reliance on animal testing, addressing ethical concerns and improving the efficiency and cost-effectiveness of preclinical research. As this technology evolves, it promises to enhance our understanding of complex biological systems and to lead to the development of more effective treatments. In this study, we developed a PDMS-based multiorgan-on-chip platform that comprises of channels mimicking the vascular capillaries and a chamber representing a given tissue-like microenvironment, facilitating dynamic interactions between cells and surrounding biomaterials.
The first part of my thesis focuses on design and development of a novel organ-on-a-chip platform aimed at studying human breast cancer intravasation. This innovative device integrates a 3D tumor microenvironment with blood capillary, mimicking human tissue conditions. Its versatility allows for the cultivation of soft tissues with variable flow rates, providing a realistic in vivo representation. The user-friendly design enables easy establishment of 3D cell cultures. The organ-on-a-chip device, supports various experimental and engineering aspects, allowing the culture of multiple organs on the same reference plane to enhance the study of complex biological interactions.
The second part of my PhD thesis conducted a comparative analysis of the intravasation rates of triple-negative breast cancer (TNBC) cells. This study examined how TNBC cells traverse a stroma-like collagenous extracellular matrix and breach the walls of capillaries to enter the vessel lumen. Contrasting static and dynamic flow conditions reveals significant differences in intravasation rates. Under dynamic flow conditions, TNBC cells show an increased capacity to intravasate compared to static conditions, indicating that mimicking appropriate physiological conditions may enhance their metastatic potential. Additionally, the study observes that proliferating endothelial cells breach the surrounding tumor matrix more readily under flow conditions, facilitating intravasation. These findings deepen our understanding of cancer metastasis mechanisms and underscore the importance of considering physiological and biological factors in tumor progression studies. Moreover, the results demonstrated that cancer cells could survive after leaving their own ECM environment, indicating their potential to extravasate and populate foreign extracellular matrix environments.
The third part of my PhD thesis examines disease modelling using the organ-on-chip device. Methylglyoxal (MG) has been used to induce dicarbonyl stress, which is associated with formation of advanced glycation end products (AGE) seen in diabetes-related diseases. Our findings reveal that MG-induced stress increases tumor intravasation, aiding cancer metastasis. Furthermore, MG adversely affects endothelial cell health and the extracellular matrix (ECM), supporting vascular capillaries and tumor cells. MG disrupts ECM integrity and promotes tumor cell migration and intravasation. Detailed ECM characterization using scanning electron microscopy and second-harmonic generation microscopy reveal structural changes, supporting our hypothesis on the role of dicarbonyl stress in enhancing cancer metastasis.
The final section of my PhD thesis details experimental findings on cancer cell intravasation and collective migration using 3D trip= le-negative breast cancer tumor spheroids in the organ-on-a-chip device. The future aspects of the organ-on-chip device facilitate cancer cells’ extravasation to the other organ studies and serve as a tool for researching cardiovascular diseases. Future experiments will incorporate branched structures of the vascular channel, enhancing the examination of flow effects alongside dicarbonyl stress. Additionally, research will focus on the role of cancer-associated fibroblasts within the tumor microenvironment and their influence on cancer cell intravasation compared to normal fibroblasts and control conditions. This comprehensive approach aims to deepen our understanding of tumor progression in general and specifically the relatively ill-investigated phenomenon of intravasation.