Metastasis Stem Cells in the Blood of Breast Cancer Patients Discovered
CD47 is an interesting target I have been google searching of late. I stumbled across this in my CD47 google search.
"Three molecules characterize the metastasis stem cell
In a systematic screening process, Baccelli first isolated cells carrying a typical protein of breast cancer stem cells (CD44) on their surface from the CTCs. This protein helps the cell to settle in bone marrow. Next, the researchers screened this cell population for specific surface markers which help the cells to survive in foreign tissue. These include, for example, a signaling molecule that protects from attacks by the immune system (CD47) and a surface receptor that enhances the cells' migratory and invasive capabilities (MET).
Using a cell sorter, the researchers were then able to isolate those CTCs which exhibit all three characteristics (CD44, CD47, MET) at once. Another round of transplantation tests showed that these really were the cells from which the metastases originated.
Depending on the patient, cells exhibiting all three surface molecules ("triple-positive" cells) made up between 0.6 and 33 percent of all CTCs. "It is interesting that only cells with the stem cell marker CD44 carry the combination of the other two surface molecules," said Irène Baccelli. "It looks like the triple-positive cells are a specialized subtype of breast cancer stem cells circulating in the blood."