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Newswise Working together, Johns Hopkins biomedical engineers and neurosurgeons report that they have created tiny, biodegradable nanoparticles able to carry DNA to brain cancer cells in mice.

The team says the results of their proof of principle experiment suggest that such particles loaded with death genes might one day be given to brain cancer patients during neurosurgery to selectively kill off any remaining tumor cells without damaging normal brain tissue.

A summary of the research results appeared online on April 26 in the journal ACS Nano.

In our experiments, our nanoparticles successfully delivered a test gene to brain cancer cells in mice, where it was then turned on, says Jordan Green, Ph.D., an assistant professor of biomedical engineering and neurosurgery at the Johns Hopkins University School of Medicine. We now have evidence that these tiny Trojan horses will also be able to carry genes that selectively induce death in cancer cells, while leaving healthy cells healthy.

Green and his colleagues focused on glioblastomas, the most lethal and aggressive form of brain cancer. With standard treatments of surgery, chemotherapy and radiation, the median survival time is only 14.6 months, and improvement will only come with the ability to kill tumor cells resistant to standard treatments, according to Alfredo Quiones-Hinojosa, M.D., a professor of neurosurgery at the Johns Hopkins University School of Medicine and a member of the research team.

Because nature protects the brain by making it difficult to reach its cells through the blood, efforts turned to the use of particles that could carry tumor-destroying DNA instructions directly to cancer cells during surgery.

The initial experiments made use of cancer cells that Quiones-Hinojosa and his team removed from willing patients and grew in the laboratory until they formed little spheres of cells, termed oncospheres, likely to be the most resistant to chemotherapy and radiation, and capable of creating new tumors.

Quiones-Hinojosa then worked with Green to find a vehicle for genes that would cause death in the oncospheres. Greens laboratory specializes in producing tiny, round particles made up of biodegradable plastic whose properties can be optimized for completing various medical missions. By varying the atoms within the plastic, the team can make particles that have different sizes, stabilities and affinities for water or oil. For this study, Greens team created dozens of different types of particles and tested their ability to carry and deliver a test sequence of DNA specifically a gene for a red or green glowing protein to the oncospheres.

Read the original here:

Brain Tumor Cells Penetrated by Tiny, Biodegradable Particles Carrying Genetic Instructions