SCATTERINGS | NEWS
Probing the
Link between
Fat and Cancer
Researchers have long believed that
fat and cancer are related, but it’s
not clear how and why high-fat diets
may cause cancer to spread. A group
of researchers from Purdue University
(West Lafayette, Ind., U.S.A.) have used
nonlinear optical microscopy to assess
the effects of fatty acids on cancer cells
in mice (BMC Cancer 9, 42).
Thuc T. Le, Terry B. Huff and Ji-Xin
Cheng found that excessive dietary fat
caused a 300 percent increase in metastasizing tumor cells. The group used a
combination of methods—including
coherent anti-Stokes Raman scattering
(CARS) microscopy, sum frequency
generation imaging and two-photon
excitation fluorescence microscopy—to
study how cancer cells act in the presence of excess lipids, in both test tubes
and the body. Multimode nonlinear
optical microscopy is attractive because,
with a range of bandpass filters, it allows
researchers to image at a variety of wavelengths and in several modes. CARS, in
Two lipid-rich cancer cells attach to collagen fibrils. Image taken using CARS and
sum frequency generation imaging.
particular, is very sensitive to lipids
and the concentration of lipids in the
active volume.
The researchers inserted tumor cells
into mice that were then fed either a
high-fat or low-fat diet. The researchers
investigated how cancer cells behaved in
high-lipid environments using intravital
flow cytometry, which detects circulating
cancer cells, and a microscopic examination of cancer cells that have spread
to the lungs. They also looked at how
mobile the cancer cells were and how
capable they were of invading tissues.
Weldon School of Biomedical Engineering, Purdue University
They found that, when there are a lot
of free fatty acids around cancer cells,
the cells incorporate them into their
membranes. This makes the cells separate
more easily and become more likely to
pass into the bloodstream. “If the cancer
cells don’t have excess lipids, they stick
together and form very tight junctions in
tumors,” Le said. “But increasing lipids
causes them to take on a rounded shape
and separate from each other.” Excess
lipids also make the membrane stickier,
allowing cancer cells to adhere more easily to tissues elsewhere in the body.
— Yvonne Carts-Powell
DID YOU KNOW?
Perhaps no musical instrument is as ubiquitous in
American life as the guitar, and Taylor Guitars (El
Cajon, Calif., U.S.A.) has brought music to many homes.
In the company’s workshop, lasers have helped make
the guitars since 1999. Engineering Services Manager
Mike Mosley explains that machines that incorporate
200-W carbon dioxide lasers are used to cut the tops,
backs and sides of the guitars.
“Utilizing a laser computer-numerically-controlled
machine provides the efficiency, safety and precision
needed to produce premium guitars,”
Mosley says. The laser doesn’t chip the
wood, as a router or shaper might. In
addition, the beam applies no pressure,
so there is less breakage. Finally, the
beam’s diameter is approximately 0.008
of an inch, which also allows for more
intricate extraction of materials, especially for detailed inlay work.
Taylor Guitars
A computer controls the position of the laser in the
guitar-cutting machine. Inset: The laser-cutting machine
creates delicate soundboard holes in a guitar.
