Researchers at Stevens Institute of Technology are developing novel cancer treatments based on ultrasmall particles of the precious metal. Measuring just several ten-billionths of a meter in diameter, these gold nanoparticles can precisely target malignant cells while sparing healthy cells, thus reducing the unpleasant side effects of standard chemotherapy and radiation.
“Gold has remarkable properties that make it an ideal vehicle for cancer treatment,” says Professor Hongjun Wang, the director of the Semcer Center for Healthcare Innovation at the Charles V. Schaefer, Jr. School of Engineering and Science who has led research efforts in this area for nearly two decades. “We have been very active in identifying multifunctional yet efficient nanocarriers and we are seeing our work truly pay off.”
Chemically inert and nontoxic, gold does not itself serve as the cancer-killer. Instead, gold acts as a means of delivering potent drugs or, after exposure to light, heating cancer cells in a highly targeted manner.
Using standard laboratory equipment, the Stevens researchers have developed a novel fabrication process that forms gold particles with suitably large pores, or holes, wherein molecules of medicine can be loaded and stored. In a recent study, published in ACS Applied Materials & Interfaces, the researchers teamed with Hackensack Meridian Health in placing an experimental anticancer drug into these gold nanoparticles. They then further weaponized the nanoparticles as cancer-seekers by encapsulating them with hyaluronic acid, a biomolecule to which certain kinds of cancer cells, such as those of lymphoma, readily bind.
When the drug-carrying gold nanoparticles were administered to mice, tumors in the rodents shrunk significantly. Furthermore, the mice showed no signs of toxicity or evidence of the anticancer drug freely floating in their blood, revealing the pharmaceutical payload had safely reached its intended target.
Because the gold nanoparticles are so stable, they could remain circulating in the bloodstream for far longer than other chemotherapeutic agents — potentially opening the door to reducing the frequency of current medication regimens, for instance from daily to weekly or even monthly, Wang says.
The promise does not end there. Other ongoing work by the Stevens researchers centers on how gold nanoparticles, after attachment to cancer cells, can be heated up inside the body by simply shining harmless infrared light through patients’ skin. The upshot: selective “cooking” of tumors, while avoiding collateral damage to healthy tissue, in contrast to imprecise radiation treatment.
This cancer cell affinity and responsiveness to light also means that gold nanoparticles can be utilized in medical imagery to “light up” cancer cells, helping clinicians visualize tumors and surgeons know where to cut during tumor removal.
Moving forward, Wang and his colleagues look forward to developing the framework further for testing in humans. “We’ve come a long way and are nearly there in delivering real benefits to cancer patients and their loved ones,” says Wang.
— Adam Hadhazy