Nanoparticles With a Heart of Gold Can Kill Cancer CellsGold’s been used for thousands of years to treat disease. Credit: Flickr user
covilhaOver
thousands of years,
gold has been used to treat rheumatoid arthritis, inner ear infections,
facial nerve paralysis, fevers and syphilis. Now, preliminary findings
suggest a new application for tiny grains of gold—destroying cancer
cells.
Gold-carrying nanoparticles are capable of killing a common type of
cancer that attacks antibody-making B cells in the blood, according to a
study published today in the journal
Proceedings of the National Academy of Sciences.
This cancer, B-cell lymphoma, originates in the lymph glands and is the
most common type of non-Hodgkin lymphoma. Last year, it resulted
in nearly 19,000 deaths.
Developed by researchers at Northwestern University, the nanoparticle
mimics the size, shape and surface chemistry of high-density
lipoprotein—natural HDL—the preferred meal of these cancer cells. HDL is
the “good” cholesterol that
cruises through the bloodstream, removing dangerous buildups of LDL, the harmful, “bad” cholesterol.
The bits of gold tucked inside these particles are tiny—just five nanometers wide. A billionth of a meter, a
nanometer is a measurement used to size bacteria, X-rays and DNA. The width of a double helix is about two nanometers.
Despite its microscopic size, the synthetic particle packs a big punch—more accurately, two of them. Recent
research has
shown that B-cell lymphoma is dependent on the uptake of natural HDL,
from which it derives fat content, to spur cell proliferation. The
nanoparticle cuts off its supply. Masquerading as natural HDL, the
nanoparticle latched on to cholesterol receptors on deadly lymphoma
cells. First, the nanoparticle’s spongy surface sucked out the cell’s
cholesterol. Then, it plugged up the cancer cell, preventing it from
absorbing natural HDL particles in the future. Deprived of this
essential nutrient, the cell eventually died.
Natural HDL alone didn’t kill the cells or inhibit tumor growth in
the study. The blinged-out particle was key to starving the lymphoma
cell—and it did so without the help of cancer drugs.
It also didn’t appear to be toxic to other human cells normally
targeted by HDL particles, to normal lymphocytes (a type of white blood
cells) or to mice, in which the particle actually inhibited tumor
growth. Developing a drug therapy using this nanoparticle depends on
further extensive testing, but it could take chemotherapy off the table
for the thousands of patients diagnosed with B-cell lymphoma.
Source:-
http://blogs.smithsonianmag.com/science/2013/01/nanoparticles-with-a-heart-of-gold-can-kill-cancer-cells/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+smithsonianmag%2Fscience-nature+%28Science+%26+Nature+|+Smithsonian.com%29