Kevin was born in Seoul, S. Korea and raised in Ithaca, NY, constantly moving back and forth between the two countries. He obtained his B.S. (2010) and M.S. (2012) in chemistry, both from Sungkyunkwan University in S. Korea. During the course, he studied the effects of nitrogen doping on the electrocatalytic properties of mesoporous carbon thin films. He then served in the Republic of Korea Air Force as a lieutenant in charge of CBRN warfare and disaster management. Currently, he is moving on to his 2nd year at the Chemistry dept. of the University of Minnesota. Kevin is working on polyacrylamide gels with stiffness gradients to study durotaxis of glioma cells. He is also working on protein-polymer conjugates for drug delivery.
Department of Biomedical Engineering, University of Minnesota
Glioblastoma multiforme (GBM) is the most severe grade 4 brain cancer. The conventional treatment which involves surgical resection of the tumor shows low recovery rates, only 2.2% of the patients surviving for more than three years. The main reason for this is the propagation of glioma cells to the surrounding tissue, which makes its complete removal nearly impossible. Therefore, to prevent the regeneration of the tumor, it is crucial to understand the mechanisms of glioma cell migration.
Cell migration can be caused by a variety of external stimuli. Those that are specifically controlled by stiffness gradient of the substrate is known as durotaxis. Here we report platform materials to study the mechanisms of gloma cell durotaxis, along with computational studies to build models to predict this behavior.
Polyacrylamide gels that mimic the tissue scaffold were used in our experiments. In these gels, we incorporated a photocleavable crosslinker that has a 2-methoxy-4 nitrobenzyl moiety that can be cleaved upon UV irradiation. This was to create a stiffness gradient on the gel by controlling the amount of UV exposure. Afterwards, a layer of 1-D patterned tracks of fibronectin was coated on the gels as an extracellular matrix (ECM), which is essential for cell attachment. The created patterns were to allow better quantification of directional migration. Glioma cells were then transferred onto the gels, and their attachment only on the fibronectin-coated areas was confirmed. The photocleavable crosslinker along with the products from photocleavage had no effect on cell viability, which proved its utility as a platform material to study durotaxis.
Future plans are to observe durotaxis on stiffness gradients that are spatially and temporally controlled. These experimental results will then be compared with predictions of the Motor-Clutch computational model made by our collaborators.