The cytoskeleton plays a very important role in upholding the mechanical integrity and controlling the movement of the cell. One technique to probe into the mechanical properties of the cell, which is influenced by the cytoskeleton, is to use micropipette aspiration as it allows us to measure the elasticity and observe the behaviour of the cell when it is subjected to external stimuli. In our study, micropipette aspiration was used to compare the mechanical properties between two types of inherently different breast cancer cell lines, MCF-7 and BT-474. BT-474 cells are perceived to be more aggressive than MCF-7 cells, as they tend to metastasize extensively to the other parts of the body and proliferate rapidly due to the over expression of HER-2 protein on the surface of its membrane. The rupture strength test showed that BT-474 cell membrane has more than twice the tendency to rupture as compared to MCF-7, which suggests that they (BT-474 cell membranes) are more rigid and vulnerable to shear stresses. This is linked to the over expression of HER-2 protein on the membrane surface and approximately half the strength that is needed to rupture MCF-7 cell membrane is required to rupture the BT-474 cell membrane. Data from the micropipette aspiration also showed a lower Young’s modulus for BT-474 cells, which implies that it has a softer and more elastic cell body as compared to MCF-7 cells. This might provide us with a clue to the higher metastasis rate of BT-474.Bachelor of Engineering (Chemical and Biomolecular Engineering
