JOHNSON CITY, Tenn. (WJHL) – Researchers at East Tennessee State University are one step closer to developing a new drug to treat bladder cancer.
And it’s all thanks to an enzyme.
Dr. William Stone, professor of pediatrics at East Tennessee State University’s Quillen College of Medicine, said he and his team could be closing in on a new prodrug that would halt the growth of bladder cancer cells.
Stone said researchers have known for a while that bladder cancer cells produce an enzyme called an esterase. Human bodies are home to many different kinds of these enzymes, so he set out to pinpoint which one was being produced in bladder cancer patients.
He got his answer – oxidized protein hydrolase. He and his team even found that the levels of the protein appear to correlate with the severity of bladder cancer.
That means the potential for a drug that can single out the cancer cells and destroy them.
“This is kind of like a cancer bullet,” he said. “It’s only activated by this enzyme, if the enzyme is high in a bladder cancer patient, then this pro-drug (activates) and kills the cancer cells.”
Stone said the hypothesis is that the enzymes are protecting the bladder cancer cells. The cancer cells have high levels of oxidated stress, he added, and that the enzyme helps protect the cancer cells from that stress.
The prodrug activates the targeted enzymes, Stone said, exposing the cells to more oxidized stress.
“If you stress (the cells) a little more, they’ll die,” He explained. “They’re using that oxidated stress to grow, so the drugs that we’re designing push them over the edge – it gives them more oxidated stress, kind of like what x-rays do, radiation therapy for cancer.”
The difference between the prodrug and something like radiation therapy is that the prodrug is developing a kind of treatment that can be tweaked to suit the needs of individual patients.
Stone called it “personalized medicine,” a practice in which treatment is tailored to each patient.
“You’ll be treating people who will respond and minimizing the side effects, (and) you won’t be treating people who aren’t going to respond but that could have adverse side effects,” he said.
Additionally, Stone’s research could help detect bladder cancer earlier. Similar enzymes have been found in prostate cancer cells, so the research could contribute to developing treatment for other cancers too.
“It may be a general property of cancers,” he said, adding that clinical trials could only be a few years away.
“We hope to bring this up to the level where it can be tested in an animal model, and then work with clinicians to bring it into actual medical practice.”
Stone’s research was funded through a grant from ETSU’s Research Development Committee. He plans to apply for an extended version of the grant through the National Institutes of Health to continue his research.
Bladder cancer affects about 68,000 people per year in the United States, and is the 6th most common cancer in adults, killing about 17,000 people per year.