To better understand the role of NEDD9 in breast cancer, the Fox Chase researchers studied a variety of mice, bred by colleagues at the University of Tokyo to lack the NEDD9 gene. These NEDD9 "knockout" mice were then made to turn on an oncogene that induces breast cancer in mice, and compared to normal mice given the same treatment. While the NEDD9 knockout mice developed breast cancers, they did so more slowly and less efficiently than normal mice, and without the activation of the central protein pathways most responsible for cancer growth and metastasis. In fact, mammary tumor growth in the knockout mice showed marked genetic differences from the very moment premalignant lesions were detected, as compared to the normal mice.

"This was the first study able to address the question of what happens in breast cancer if this gene isn't around," Golemis says. "And the answer is that we see a more moderate cancer development, which alone speaks volumes on the role of the protein in aggressive breast tumors."

According to Golemis, the emerging body of research on NEDD9 shows that the protein forms an important node in the complex, interwoven pathways that dictate the fate of individual cells. These pathways regulate the entirety of a cell's life, from how select genes are transcribed to form new proteins to how a cell divides or even dies.

"By their nature, cancer cells are evolutionary machines, constantly looking for ways to exploit these vast networks of protein signaling pathways that are an inherent part of cell function," Golemis says. "The more we understand these pathways, the better we will understand the ways cancer cells evolve to use those pathways, and how to stop them."

Source: Fox Chase Cancer Center