Biodegradable plastic molecules (orange) self-assemble with DNA molecules (intertwined, black circles) to form tiny nanoparticles that can carry genes to cancer cells. Image Source: The John Hopkins University; Credit: Stephany Tzeng.
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.
“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 Quiñones-Hinojosa, M.D., a professor of neurosurgery who treats brain cancer patients at the Johns Hopkins Kimmel Cancer Center. 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.