Nanoparticles Used to Starve Cancer Cells to Death

Researchers announced successful tests with gold-containing nanoparticles that mimic a natural substance needed by lymphoma cancer cells, which ingest the nanoparticles instead of their essential nutrition and are subsequently dying of starvation. The method stopped human cancer tumor growth in mice and could allow a nontoxic treatment of  Non-Hodgkin lymphoma cancer, which lead to 19,000 deaths in the United States last year.

The nanoparticle from the Northwestern Medicine researchers attacks a cancerous lymphoma cell by mimicking HDL (high-density lipoprotein) cholesterol in size, shape and surface chemistry , but contains a spongy gold particle inside, instead of the essential nutrient for the cell, for which recent studies showed that it depends on HDL uptake. The five nanometer gold particle at its core is bad in two ways for the human B-cell lymphoma cells: it sucks out existing cholesterol, but also prevents the cell from absorbing more cholesterol typically carried in the core of natural HDL particles.

The new study by C. Shad Thaxton, M.D., and Leo I. Gordon, M.D., both at the Northwestern University Feinberg School of Medicine, shows that these synthetic HDL nanoparticles annihilated B-cell lymphoma, the most common form of the disease, in cultured human cells, and inhibited human B-cell lymphoma tumor growth in mice.

"This has the potential to eventually become a nontoxic treatment for B-cell lymphoma which does not involve chemotherapy," said Gordon. "It's an exciting preliminary finding."

According to the National Cancer Institutes there were about 70,000 new cases of non-Hodgkin lymphoma in the U.S. with nearly 19,000 deaths in 2012. About 90 percent of those new cases were B-cell lymphoma. Non-Hodgkin lymphoma is a cancer that starts in cells called lymphocytes, which are part of the body's immune system.

The research was supported by The Howard Hughes Medical Institute and the Schwartz Foundation. Thaxton is a co-founder of AuraSense, LLC a start-up biotech company that holds the license to the HDL nanoparticles used in the study.

The paper was published on Monday, January 21, in the journal Proceedings of the National Academy of Sciences:
Shuo Yang et al., Biomimetic, synthetic HDL nanostructures for lymphoma, Proceedings of the National Academy of Sciences, 2013, DOI: 10.1073/pnas.1213657110