Published in Nature Communications, their study demonstrated the potential application of a technique that uses nanoparticles and near infrared laser treatment to cause cancer cells to lose their multidrug resistance capabilities.
Multidrug resistance presents a major problem for oncology treatment. Cancers have the ability to develop resistance to traditional therapies, causing chemotherapy to fail. Chemotherapy can be used to kill the drug-sensitive cancer cells, but the drug-resistant cells that remain can cause tumours to return and cancer metastasis─the development of secondary tumours in other parts of the body.
One of the main reasons cancer cells develop resistance is the overexpression of efflux pumps─proteins that protect a cell by pumping out unwanted toxic substances before they can reach their intended target. These cause multidrug resistance by pumping out chemotherapy drugs before they can eliminate cancer cells.
Tested by the researchers on mice, the new technique works by delivering drug-laden nanoparticles and near infrared laser treatment to the mitochondria of the cancer cells. This prevents chemical energy from being supplied to the efflux pumps, thus causing them to lose their multidrug-resistant abilities.
Researchers found that the cells lost their resistance to drugs for at least five days, long enough for chemotherapy to target the once-resistant cells. This means that, if the technology is developed for use in humans, cancer patients may require a lower dose of chemotherapy.
Bioengineering professor and lead researcher He Xiaoming said: “For years, researchers have focused on delivering more chemotherapy drugs into cancer cells using nanoparticles, without targeting the root of drug resistance.
“This meant that the cancer cells maintained their ability to expel the chemotherapy drugs, which limited any enhancement of the cancer therapy. To address this challenge, our research group is using nanoparticles not only to deliver more chemotherapy drugs to the target site within cancer cells, but also to compromise the function of the efflux pumps and thereby significantly improve safety and efficacy of cancer therapy.”
The study provides a promising nanotechnology-based strategy for fighting against cancer multidrug resistance.