Using nanotechnology, UCLA researchers discover cancer cells 'feel' much softer than no...(agnostic methods detect about 70 percent...)

We detect cancer cells typically by looking at them under a microscope after the cells are fixed and stained with chemicals, which is really an antiquated method, Rao said. Usually the cancer cells have larger nuclei and other subtle features. However, the normal cells from body cavity fluids can look almost identical to cancer cells under an optical microscope. While staining for tumor protein markers could increase diagnostic accuracy, what we were missing was a way to determine if cancer cells have different mechanical properties than normal cells.

Employing one of the most valuable tools in the nanotechnology arsenal, the research team used an Atomic Force Microscope (AFM) to measure cell softness. Since the cells being analyzed were less than half the diameter of a human hair, researchers needed a very precise and delicate instrument to measure resistance in the cell membrane, said James Gimzewski, professor of chemistry and biochemistry, a member of the California NanoSystems Institute and also one of the studys senior authors.

We had to measure the softness of the cell without bursting it, Gimzewski said. Otherwise, its like trying to measure the softness of a tomato using a hammer.

The AFM uses a minute, sharp tip on a spring to push against the cell surface and determine the degree of softness. Think of it as an extension of a doctors hands performing a physical examination to determine disease, Gimzewski said.

You look at two tomatoes in the supermarket and both are red. One is rotten, but it looks normal, Gimzewski said. If you pick up the tomatoes and feel them, its easy to figure out which one is rotten. Were doing the same thing. Were poking and quantitatively measuring the softness of the cells.

After probing a cell, the AFM assigns a value that represents how so
'/>"/>