Event
BIOE Seminar:Aberrant glycosylation regulates membrane surface architecture and viscoelasticity of..
Friday, May 1, 2026
9:00 a.m.
A. James Clark Hall, Room #2121
Kimberly Stroka
kstroka@umd.edu
Alexander X. Cartagena-Rivera
National Institute of Biomedical Imaging and Bioengineering
Aberrant glycosylation regulates membrane surface architecture and viscoelasticity of pancreatic cancer cells
Abscract
The cellular glycocalyx plays a crucial role in making pancreatic cancer one of the deadliest malignancies globally. It complicates early detection and reduces the effectiveness of conventional therapies. In pancreatic cancer, the components of the glycocalyx are often upregulated or abnormally glycosylated, promoting tumor progression through immune evasion, enhanced metastasis, and drug resistance. While these biochemical effects are known, the biophysical impact of the glycocalyx on cancer cells is less understood. In our study, we explored the structural and biomechanical effects of modifying the glycocalyx architecture in pancreatic cancer cells using various chemical compounds. We employed a recently developed Atomic Force Microscopy nanomechanical mapping method to visualize cellular mechanical heterogeneities in a high spatiotemporal context. Our new approach allows for the viscoelastic inversion of high-resolution spatiotemporal data at rates which are orders of magnitude faster (more than 37,386-fold) than optimizing a traditional rheological model for each pixel. Then, we investigated the architectural and biophysical effects of glycocalyx architectural modulation in pancreatic cancer cells. Perturbations of hyaluronic acid (HA), sialic acid (SA), mucins, and N-glycans through enzymatic treatments led to significant architectural remodeling of the cell surface. Interestingly, removal of SA and mucins resulted in a softer and more fluid cell surface, while removal of HA softened and increased viscosity. In addition, preliminary cytokine expression results suggested that SA removal leads to a pronounced pro-inflammatory response (IL-2, IL-8, INF-γ among others) of human cytotoxic CD8+ T Lymphocytes, greater than removing other glycocalyx components. Lastly, a glycomics study also revealed unique changes in the structure of N- and O-glycans, with significantly more heterogeneity in the structure of N-glycans on pancreatic cancer cells, and O-glycans showing a particularly higher degree of SA deposition. Linkage studies further confirm the overabundance of 2-3 linked sialic acid residues in cancerous cells. Altogether, our findings suggest that enhanced sialylation of the glycocalyx of human pancreatic ductal adenocarcinoma cells fundamentally regulate extracellular surface architecture, mechanical properties, composition, and function, thereby promoting tumor progression and metastasis by acting as a physical barrier to antitumor responses.
Bio
Dr. Alexander X. Cartagena-Rivera received his Ph.D. in Mechanical Engineering from Purdue University in 2014. Dr. Cartagena-Rivera joined the National Institute of Biomedical Imaging and Bioengineering (NIBIB) at the National Institutes of Health as an Earl Stadtman Tenure-Track Investigator position in 2019. He currently serves as the Chief of NIBIB’s Section on Mechanobiology, where he leads a research program focused on understanding the molecular-mechanical regulation of cells and tissues. His group also develops advanced atomic force microscopy technologies to support research in cancer biology, hearing research, and immune response.
