Biophysics Seminar day - 11/18/2016 - 11:00am-1:30pm - 1080 Physics Research Building

11:00-12:00 Engineering the Tumor's Physiochemical Microenvironment
Jonathan Song, Department of Mechanical and Aerospace Engineering

In tumors, interactions between malignant cancer cells and non-malignant cells create the tumor microenvironment (TME). The interactions of the TME are dynamic and complex, often promote tumor function at all stages of carcinogenesis, and have largely been described by the intercellular communication mediated by biochemical signaling molecules. However, research in the past 15 years has suggested that a tumor's physical environment, which includes direct physical interactions between cells and tissue-level mechanical stresses, can influence cancer growth and invasion, alter a tumor's material properties, and cause treatment resistance. However, barriers for studying the direct effects of the tumor promoting properties of the physical environment include the challenges of experimentally manipulating the physical microenvironment in in vivo tumor models and successfully simulating this microenvironment in vitro. To advance past these barriers, our group leverages 3-D microengineering technologies, which provide unprecedented capabilities for reconstituting the cellular and extracellular matrix (ECM) microarchitecture and microenvironment of tumors in a controllable and versatile model system in vitro, to dissect the tumor promoting properties of the physical microenvironment. More specifically, this presentation will highlight ongoing work investigating the role of fluid mechanical stresses, including 3-D interstitial flow and interstitial fluid pressure (IFP), in regulating the behavior of two important cell types of the TME: 1) stromal fibroblasts and 2) endothelial cells that comprise blood vessels. By providing opportunities to decipher the complexity of tumors in a reductionist way, our 3-D microengineered cell culture models will provide new and important insights on the biological and physiochemical characteristics of the TME.

12:30-1:30 Measuring and modeling the mechanics of morphogenesis
Shane Hutson, Vanderbilt University

Organismal development is often traced back to the unfolding of an intricate genetic program, but this unfolding requires physical interactions between cells. Developing embryos build and reshape tissues through the actions of intra-embryo, cell-generated mechanical forces. I will detail my group's efforts to measure and model these forces to better understand how they drive morphogenesis. We focus on two key events in fruit fly embryos - germband retraction and dorsal closure - using a combination of laser-microsurgery, live-embryo confocal microscopy, and cell-level finite-element modeling. I will just begin to touch on the wealth of questions in developmental biology that could benefit from the collaborative attention of biologists and physicists.

Last update: 11/7/2016, Ralf Bundschuh