A protein, called DENND2B, commonly found in human cells can be an important switch that activates cancer cell metastasis, revealed researchers at the Montreal Neurological Institute and Hospital. This discovery significantly expands the understanding of epithelial cancers such as breast and lung cancer.
The researchers examined the function of a protein called DENND2B. During childhood development, DENND2B was found to play a role in the normal migration of cells. In adults cell migration is greatly reduced. However, in the case of cancer, there is unwanted cell migration, contributing to one of the most puzzling aspects of cancer cells, metastasis to new locations.
Principal researcher Peter McPherson said, "DENND2B activates another protein in the cell called Rab13, which is an enzyme that promotes cell migration."
Researcher Maria Ioannou said, "We found that Rab13 has an unusually high degree of expression in many forms of cancer, especially epithelial cancers that often metastasize to the brain. It was important to see exactly where in the cell Rab13 was being turned on to figure out how it functions. We saw that the DENND2B protein was activating Rab13 at the leading edge of the cell, an important point for cell migration."
Researchers see Rab13 as a focus for future research into cancer therapies. McPherson said, "In the case of the cells with reduced Rab13 levels, the cancer either did not grow at all or formed a smaller tumor and furthermore, the smaller tumor did not metastasize into other tissue. No one had considered targeting Rab13 in relation to cancer before this study. Clinical trials involving the discovery are still some time away."
The study will appear in the Journal of Cell Biology.