Public release date: 30-May-2012 [ | E-mail | Share ]

Contact: Dian Land dj.land@hosp.wisc.edu 608-261-1034 University of Wisconsin-Madison

MADISON Breast-cancer researchers at the University of Wisconsin-Madison have found that two related receptors in a robust signaling pathway must work together as a team to maintain normal activity in mammary stem cells.

Mammary stem cells produce various kinds of breast cell types. They may also drive the development and growth of malignant breast tumors.

Published recently in the Journal of Biological Chemistry, the research also suggests that a new signaling pathway may be involved, a development that eventually could take cancer-drug manufacturers in a new direction.

"We wanted to know if we could use this knowledge to inform us about what might be the transition that occurs to start tumor growth and maintain it," says senior author Dr. Caroline Alexander, professor of oncology at the McArdle Laboratory for Cancer Research at the School of Medicine and Public Health.

The paper describes new information about the Wnt signaling pathway. Wnt signaling underlies numerous activities in normal development, but when the system is unregulated, cancer often occurs.

"Wnt signaling is very important for both stem cells and tumor growth. We need to know the details of the signaling process so that we can use the positive aspects of Wnt signaling for regenerative medicine, and eliminate the negative cancer-causing aspects," says Alexander, a member of the UW Carbone Cancer Center (CCC).

Regenerative biologists typically add Wnt proteins together with other agents to guide the differentiation of lung, bone and heart stem cells, she notes.

The UW researchers zeroed in on two related Wnt receptors on the cell surface--LRP5 and LRP6. The receptors normally respond to Wnt ligands that approach cells to initiate a signaling cascade inside.

Original post:
Breast stem-cell research: Receptor teamwork is required and a new pathway may be involved