Effect of External Force and Shear Stress on Tumor Cell Mechanics and Membrane Receptor-Ligand Interactions

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Jul 18, 2012 (5 years and 1 month ago)

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Department of Mechanical and Biomedical Engineering

Seminar Series

Effect of External Force and Shear Stress on Tumor Cell
Mechanics and Membrane Receptor-Ligand Interactions

Dr. Luthur Siu-Lun CHEUNG
Department of Chemical and Biomolecular Engineering,
Johns Hopkins University, USA

Date:
3 Jan., 2011 (Tuesday)
Time:
2:30pm – 3:30pm < Tea Reception at 2:15pm >
Venue:
Room B6619 (SEEM & MBE Conference Room)

ABSTRACT
Cell adhesive interactions play pivotal roles in major
(patho)physiological vascular processes, such as inflammation,
thrombosis, and cancer metastasis, and are regulated by hemodynamic
forces generated by blood flow. On one hand, fluid shear induces
collisions between free-flowing cells and the vessel wall, thereby
increasing the encounter rate between membrane receptors and their
ligands. On the other hand, fluid shear exerts forces that tend to disrupt
the receptor-ligand bonds responsible for cell adhesion. Cell-cell
interactions, therefore, depend on the balance between the dispersive
hydrodynamic forces and the adhesive forces generated by the
interactions of receptor-ligand pairs. Elucidating molecular and
biophysical properties of the tumor cell may provide guidelines for
developing promising therapeutic strategies to combat cancer metastasis.

The protein-protein interface is built by a series of amino acid residues
which form hydrophobic interactions and hydrogen bonds, as such the
binding free energy may not be uniformly distributed among these
interfacial residues. It is believed that only a small group of "hot-spot"
residues significantly contributes to the biomolecular recognition. This
presentation will discuss the effect of external force and shear stress on
tumor cell mechanics and protein-protein interactions. The following
topics will be included: (1) utilizing microfluidics devices and protein
patterning technology to study the adhesion kinetics of tumor cells
under shear flow; (2) the role of membrane deformation in response to
flow acceleration (dQ/dt) in tumor cell detachment in a microchannel; (3)
characterization of the binding interaction between an engineered
protein and its target ligand under loading force.

ABOUT THE SPEAKER
Dr. Luthur Siu-Lun Cheung received his B.Eng degree with first-class
honor in mechanical engineering from the Hong Kong University of
Science and Technology (HKUST) in 2003. He was a junior research
assistant at HKUST from 2003 to 2004, studying bubble dynamics in a
microscale environment using microfluidic devices and simulations.
Later on, Dr. Cheung moved to the University of Arizona, US, where he
earned his Ph.D in 2009 in mechanical engineering (minor in applied
mathematics) for his research on the attachment, deformation and
detachment of cancer cells in microfluidic systems. Dr. Cheung is
currently a postdoc fellow at Johns Hopkins Physical Science-Oncology
Center and Department of Chemical and Biomolecular Engineering at
the Johns Hopkins University, US.
Dr. Cheung's research focuses on applying modeling and experimental
techniques to study biomechanics, with specific focus on the effect of
external forces (such as fluid shear) on the tumor cell adhesion and
protein-protein interactions. He is author, and co-author of fourteen
peer-reviewed articles and book chapters published in Lab-on-a-Chip,
Biophysical Journal, Physical Biology, and Comprehensive Biophysics.
He also presents his research works regularly in major conferences in the
fields of Mechanical and Biomedical Engineering. In 2011, Dr. Cheung
has received a postdoctoral fellowship award from the American Heart
Association.

Enquiry: 3442 8420

All are welcome!

MBE Seminar 2011-2012/015