Scientists use titanium dioxide nanoparticles to kill cancer cells, sparing healthy ones

Washington, August 20 (ANI): Scientists in America have developed a way to target brain cancer cells using inorganic titanium dioxide nanoparticles bonded to soft biological material.

This achievement is a result of the joint efforts of scientists from the U.S. Department of Energy's (DOE) and the University of Chicago's Brain Tumor Center.

Thousands of people die from malignant brain tumours every year, and the tumors are resistant to conventional therapies.

The researchers say that their nano-bio technology may eventually provide an alternative form of therapy, which targets only cancer cells and does not affect normal living tissue.

"It is a real example of how nano and biological interfacing can be used for biomedical application. We chose brain cancer because of its difficulty in treatment and its unique receptors," said scientist Elena Rozhkova with the DOE's Argonne National Laboratory.

The novel approach relies upon a two-pronged approach.

The researchers describe titanium dioxide as a versatile photoreactive nanomaterial that can be bonded with biomolecules.

When linked to an antibody, they say, nanoparticles recognize and bind specifically to cancer cells.

When focused visible light is shined onto the affected region, the researchers add, the localized titanium dioxide reacts to the light by creating free oxygen radicals that interact with the mitochondria in the cancer cells.

Mitochondria act as cellular energy plants, and when free radicals interfere with their biochemical pathways, mitochondria receive a signal to start cell death.

"The significance of this work lies in our ability to effectively target nanoparticles to specific cell surface receptors expressed on brain cancer cells," said Dr. Maciej S. Lesniak, Director of Neurosurgical Oncology at University of Chicago Brain Tumor Center.

"In so doing, we have overcome a major limitation involving the application of nanoparticles in medicine, namely the potential of these agents to distribute throughout the body. We are now in a position to develop this exciting technology in preclinical models of brain tumours, with the hope of one day employing this new technology in patients," Lesniak added.

Using X-ray fluorescence microscopy at Argonne's Advanced Photon Source, the researchers have also found that the tumours' invadopodia, actin-rich micron scale protrusions that allow the cancer to invade surrounding healthy cells, can be also attacked by the titanium dioxide.

The researchers have thus far carried out tests on cells in a laboratory setting, but animal testing is planned for the next phase.

Results show an almost 100 percent cancer cell toxicity rate after six hours of illumination, and 80 percent after 48 hours.

Also, since the antibody only targets the cancer cells, surrounding healthy cells are not affected, unlike other cancer treatments such as chemotherapy and radiotherapy.

Rozhkova said that a proof of concept is demonstrated, and other cancers can be treated as well using different targeting molecules.

The expert, however, admits that the research is presently in the early stages. (ANI)