Why melanoma cells escape the eye and how to potentially stop them 

While many people are familiar with skin melanoma, this type of cancer can also happen in the eye. Though rare, ocular melanoma can be deadly if tumor cells spread from the eye to other organs.  

A new study in Signal Transduction and Targeted Therapy published by University of Illinois Chicago scientists examined how this metastasis happens and tested a therapy that could stop it.  

The group, led by Kaori Yamada of the College of Medicine, used an organ-on-chip laboratory assay to study how melanoma cells escape from the eye into surrounding blood vessels. They identified vascular endothelial growth factor as critical for this leakage. The growth factor causes new blood vessels to form but also weakens their walls. 

Treating melanoma cells with a drug that interrupts vascular endothelial growth factor activity prevented cancer cells from moving into surrounding blood vessels. That drug, called aflibercept, is already available clinically. But Yamada’s group went a step further and developed a peptide that interrupts vascular endothelial growth factor signaling.  

“One of the advantages is that we can use the peptide as an eye drop, while current therapies require injection into the eye,” said Yamada, UIC assistant professor of pharmacology and regenerative medicine and a member of the University of Illinois Cancer Center.  

In both laboratory and animal studies, their peptide was also effective at stopping cancer cells from escaping into the blood. In future experiments, Yamada’s group will look at how it performs against different types of ocular melanoma, as the disease can originate from different genetic mutations. 

Yamada’s group collaborated with researchers Daniel Maidana and Michael J. Heiferman in the UIC Department of Ophthalmology and Visual Sciences. Additional UIC co-authors on the paper include Nguyễn Thị Thanh Nhàn and Sanjay Ganesh of the College of Medicine. The research was supported by grants from the American Cancer Society and the National Institutes of Health.