The most promising cancer drug can’t be effective if it cannot reach the cancer.
Some researchers are trying to solve that problem by developing drug delivery vehicles that transport drugs into tumor cells without damaging healthy cells.
Carrying proven cancer drugs, nanoparticles are injected into the bloodstream like any injectable medication. They are programmed to travel through blood vessels to solid tumors. Scientists are experimenting with different materials to make nanoparticles, in search of what will work best. Those made of lipids, for instance, were invented decades ago but are too large to diffuse into tumors efficiently and are removed from the blood stream too rapidly to be effective.
The nanoparticles Luo developed are made of polymers, which are substances that contain chains or complicated structures of many molecules. The way in which the molecules are connected determines the polymer’s consistency. Some polymers are rubbery, some sticky, some tough. They are biodegradable, so after they deliver the cancer drugs, they dissolve and are excreted with urine.
Luo believes for cancer drug delivery, polymers will have to be tailored individually to the drug they are carrying, and perhaps also to the patient who will receive the injection. That’s because patients may respond differently to medications based on the stage and markers of their cancer.
His research, while early, shows promise in laboratory animals.
Over the summer in the journal Nature Communications, Luo reported about a nanocarrier that can deliver doxorubicin, a potent drug used in a variety of cancers.
His laboratory at Upstate identified the optimal building blocks of a specific polymer and designed a drug-binding molecule that would not sacrifice the stability of the nanocarrier. Doxorubicin was then transported in the nanocarrier through the bloodstream to the cancer cells the drug destroys.
With a reliable way of transporting the drug through the body to the cancer, Luo explained how doctors may one day be able to safely prescribe higher doses of doxorubicin. “That will increase the efficacy and also decrease toxicity,” he said. It will help the drug be more powerful against cancer, while causing fewer toxic side effects.
This article appears in the fall 2015 issue of Cancer Care magazine.