A team of scientists has identified a new way to block the spread of cancer cells, offering hope for new treatments for a variety of cancers.

The researchers, from the University of California, San Francisco (UCSF), found that a protein called CD47 plays a key role in allowing cancer cells to evade the immune system. By blocking CD47, the researchers were able to significantly reduce the spread of cancer cells in mice.

"Our findings suggest that CD47 could be a promising new target for cancer therapy," said study leader Dr. John T. Wilson, a professor of medicine at UCSF. "By blocking CD47, we may be able to prevent cancer cells from spreading and forming new tumors."

CD47 is a protein that is expressed on the surface of all cells. It helps to protect cells from being attacked by the immune system. In cancer cells, CD47 is often overexpressed, which allows them to evade immune detection and grow unchecked.

The researchers found that CD47 binds to a protein called SIRPα on the surface of immune cells. This binding prevents the immune cells from attacking the cancer cells. By blocking CD47, the researchers were able to disrupt this interaction and allow the immune cells to kill the cancer cells.

The researchers tested their approach in mice with a variety of cancers, including breast cancer, lung cancer, and melanoma. They found that blocking CD47 significantly reduced the spread of cancer cells in all of the mouse models.

The researchers are now planning to start clinical trials of CD47 inhibitors in patients with cancer. They believe that CD47 could be a promising new target for cancer therapy, and that blocking this protein could help to improve the outcomes of patients with cancer.

The study was published in the journal Nature Medicine.