For the vast majority of people who die from cancer, the first tumors doctors find aren’t the malignancies that kill them. Instead, the culprits are the cancer cells that break away from primary tumors and give rise to secondary tumors, often in other parts of the body.
This is why patients can undergo seemingly succesful cancer treatments involving surgery, chemotherapy and radiation treatment only to have other malignancies discovered years later.
It may look as if someone who has undergone this sort of comprehensive treatment regimen cancer free. Unfortunately, tiny tumors created by cells from the original cancer may already be growing in places like the bones, brain or liver.
Because of this researchers at the University of Arkansas are looking for better ways to find and kill cancer cells that have spread from primary tumors. Doctors cause this spreading of malignant cells metastisis.
“Metastasis, not the primary tumor, kills about 90 percent of cancer patients,” said the leader of the research effort, Daid Zaharoff, an assistant professor of biomedical engineering at Arkansas. “Our work has the potential to significantly reduce this percentage.”
The research by Zaharoff’s team is being helped by a 5-year, $1.5 million grant from the National Cancer Institute, part of the National Institutes of Health.
The focus of research by Zaharoff, who holds the Twenty-First Century Professorship in Biomedical Engineering at the University of Arkansas College of Engineering, has been cytokines, a group of small protein molecules that cells used to send signals involved in various processes, including the immune response.
In research begun when he was a postdoctoral fellow in the Laboratory of Tumor Immunology and Biology at the NCI, Zaharoff used the cytokine Interleukin-12, in combination with a naturally occuring carbohydrate molecule called chitosan, to successfully target bladder cancer in lab mice.
The chitosan helps improve the delivery of interleukin-12 to cancer cells. Interleukin-12 has two possible cancer fighting properties, stimulate the production and growth of immune system components known as “killer cells” and blocking the formation of the blood vessels tumors needed to survive and thrive.
In this latest round of research, Zaharoff’s collaborator, Suresh Kumar, associate professor in the Arkansas department of chemistry and biochemistry, will concentrate on the protein molecules. Zaharoff’s focus will be on ways to deliver to cancer cells whatever Kumar comes up with.
“This project is a perfect example of the power of collaboration,” Zaharoff said. “Our progress would be significantly slower if it weren’t for Suresh and his lab.”