CHICAGO, Oct. 25 (Xinhua) -- Stemlike cells at the edge of melanoma tumors secrete factors promoting new blood-vessel formation to feed cancerous tumors, particularly when the cells are under strain from a tumor's complex topology, a study of the University of Illinois (UI) found.
This points to new considerations for assessing tumors, as researchers have known for a long time that cells in low-oxygen environments at the center of the tumor send out these factors.
Researchers used melanoma microtumors grown in engineered environments that simulate conditions within body tissues. The tumors took a variety of shapes. The researchers compared periphery cells strained into curved shapes and cells from smoother tumors to see if the strain affected what the cells secreted.
"Cells exposed to strained topologies at the perimeter secreted much higher levels of growth factors that promote blood vessels," said Kristopher Kilian, a UI professor of bioengineering and of materials science and engineering who led the research. "And they did this at normal oxygen levels using the same pathway that we see in low-oxygen cells at the center of tumors, but in this case mechanical cues are responsible."
"The flexibility of cancer is one of the big dangers," said Kilian. "Cancer can adapt itself to establish optimal roots, to coordinate its own viability and dissemination."
This is the first time a link has been established between stem cell-like melanoma-initiating cells and angiogenesis.
"This is important for prognosis and for therapeutic development," Kilian said.
Kilian's team is working to verify its results in human tissue.
The study has been published in the journal Science Advances.