Can a promising cancer drug also treat tuberculosis (TB), the world’s single deadliest infectious disease? Researchers at the Texas Biomedical Research Institute, host institution for the Southwest National Primate Research Center, think so.
The team discovered a mechanism for regulating cell death – called apoptosis – that could help control the bacterial infection that causes TB. Dr. Eusondia Arnett and her colleagues tested this concept by infecting human immune cells called macrophages with the TB bacterium, then treating those infected cells with the potential cancer treatment. The result was an 80% reduction in the growth of the TB bacterium.
“Induction of apoptosis and subsequent reduced growth of the TB bacterium should ultimately result in less inflammation and damage to the lungs, and increased control of TB,” said Dr. Arnett.
One-fourth of the world’s population is infected with TB, according to the Centers for Disease Control and Prevention, including 9,000 new cases in the United States in 2017. Up to 13 million people in America carry the latent TB infection, with 5-10% developing infectious TB in their lifetimes. (The majority of those infected were born outside the U.S. and infected prior to arriving in the country from areas of the world where TB is more common.)
TB infection also creates dense cellular structures, called granulomas, in the lungs of infected persons. Granulomas are the body’s attempt to wall off an infection it is unable to eliminate. But they also provide a niche for the bacteria to become resistant to antibiotics. Dr. Arnett’s study showed that these experimental cancer drugs also reduced TB bacteria growth in granulomas in a human model, holding promise for these drugs in humans and animals.
Dr. Larry Schlesinger, President and CEO of Texas Biomed, said this finding highlights the critical role of basic scientific research.
“When we study important host cell pathways for disease, we can find relationships we didn’t even know existed,” he explained. “We can forge new ways to use current knowledge to create novel strategies for therapy for infection to be used along with antibiotics.”
The drugs used in this study are already in Phase II of Food and Drug Administration clinical trials. The next step for testing the drugs’ effectiveness in treating TB is a mouse model, followed by nonhuman primate models and ultimately, human clinical trials.