Stefano Zapperi's abstract
Stefano Zapperi, CNR-IENI, Milano, Italy
Mechanical stresses in tumor growth
Understanding the role of microenvironment in cancer growth and metastasis is a key issue for cancer research. We study the effect of osmotic pressure on the functional properties of primary and metastatic melanoma cell lines. In particular, we experimentally quantify the effect of osmotic pressure on cell growth, motility, transmigration capability and invasion of an empty space. Our results show that primary melanoma cells are sensitive to a low osmotic pressure, while metastatic cells are less. We compare the experimental results with the theory of branching process and cellular automata models for cell growth and motility, finding a very good agreement. Next, we propose a computational model to understand the role of mechanics in the growth of melanocytic nevi, benign proliferations that sometimes turn into malignant melanoma in a way that is still unclear from the biochemical and genetic point of view. Numerical simulations suggest that the morphology of the nevus is correlated to the initial location of the proliferating cell starting the growth process and to the mechanical properties of the tissue. Our results also support that melanocytes are subject to compressive stresses that fluctuate widely in the nevus and depend on the growth stage. Numerical simulations of cells in the epidermis releasing matrix metalloproteinases display an accelerated invasion of the dermis by destroying the basal membrane.
Joint work with Caterina La Porta