Researchers at the University of Wisconsin School of Medicine and Public Health have found that removing a specific type of collagen can dramatically reduce the growth of one form of breast cancer.
Daniel Greenspan, UW-Madison professor of cell and regenerative biology, and three colleagues examined the role of this collagen – the main class of structural proteins in connective tissues, like skin – in luminal breast tumors. The specific collagen chain they examined is called alpha 3V.
Their research showed that when this collagen was removed in mice, the growth of luminal tumors was greatly reduced, Greenspan said.
“When a type of mouse that gets breast cancer was crossed with mice that don’t have the alpha 3V collagen, tumor growth rate slowed and mouse survival time increased,” Greenspan said.
The results of the research were recently published in the journal Nature Communications.
Alpha 3V collagen is produced at high levels in the outer lining (basal cells) of the normal mammary duct, but begins to be produced in the inner lining (luminal cells) of the duct when these cells become cancerous.
Breast tumors, including luminal tumors, are thought to form from cells in the luminal layer, Greenspan said.
The alpha 3V type of collagen is also present in skeletal muscle and parts of the pancreas, in which it is thought to be important for proper functions of specific parts of these tissues.
Discovering the link between alpha 3V collagen and luminal tumors in breast duct tissue has prompted Greenspan to immediately seek funding to create better antibodies against alpha 3V collagen.
Antibodies – proteins created by the immune system to attack foreign objects like bacteria or viruses – against the alpha 3V collagen also were found to slow tumor growth.
There are three other primary forms of breast cancer, luminal B, triple negative/basal-like, and HER2, but levels of alpha 3V collagen appear to correlate best with the appearance of luminal A breast tumors in humans.
The potential for this anti-alpha 3V treatment to greatly slow luminal A breast cancer, as part of a broader treatment plan, could allow for more effective treatments, according to Greenspan
“It could be another arrow in the quiver of the clinician,” he said.