Method found to have greater cancer-killing efficiency than existing treatments.
Researchers at UCLA’s Jonsson Comprehensive Cancer Center have developed an innovative drug-delivery system in which tiny particles called nanodiamonds are used to carry chemotherapy drugs directly into brain tumors. The new method was found to result in greater cancer-killing efficiency and fewer harmful side effects than existing treatments.
The research, published in the advance online issue of the peer-reviewed journal Nanomedicine: Nanotechnology, Biology and Medicine, was a collaboration between Dean Ho of the UCLA School of Dentistry and colleagues from the Lurie Children’s Hospital of Chicago and Northwestern University’s Feinberg School of Medicine. Ho co-directs UCLA Dentistry’s Weintraub Center for Reconstructive Biotechnology and is a professor in the division of oral biology and medicine, the division of advanced prosthodontics, and the department of bioengineering.
Glioblastoma is the most common and lethal type of brain tumor. Despite treatment with surgery, radiation and chemotherapy, the median survival time for glioblastoma patients is less than one-and-a-half years. The tumors are notoriously difficult to treat, in part because chemotherapy drugs injected alone often are unable to penetrate the system of protective blood vessels that surround the brain, known as the blood–brain barrier. And those drugs that do cross the barrier do not stay concentrated in the tumor tissue long enough to be effective.
The drug doxorubicin, a common chemotherapy agent, has shown promise in a broad range of cancers, and it has served as model drug for the treatment brain tumors when injected directly into the tumor. Ho’s team originally developed a strategy for strongly attaching doxorubicin molecules to nanodiamond surfaces, creating a combined substance called ND–DOX.
Nanodiamonds are carbon-based particles roughly 4 to 5 nanometers in diamter that can carry a broad range of drug compounds. And while tumor-cell proteins are able to eject most anticancer drugs that are injected into the cell before those drugs have time to work, they can’t get rid of the nanodiamonds. Thus, drug–nanodiamond combinations remain in the cells much longer without affecting the tissue surrounding the tumor.