Many cancer cells have 'eat me' signal: Study

Washington, Dec 23 (ANI): A new study has found that many cancer cells carry the seeds of their own destruction - a protein on the cell surface that signals circulating immune cells to engulf and digest them.

On cancer cells, this "eat me" signal is counteracted by a separate "don't eat me" signal that was described in an earlier study. The two discoveries may lead to better cancer therapies, and also solve a mystery about why a previously reported cancer therapy is not more toxic.

Researchers at the Stanford University School of Medicine discovered that many forms of cancer display the protein calreticulin, or CRT, which invites immune cells called macrophages to engulf and destroy them.

The reason most cancer cells are not destroyed by macrophages is that they also display another molecule, a "don't eat me" signal, called CD47, which counteracts the CRT signal.

"This research demonstrates that the reason that blocking the CD47 'don't eat me' signal works to kill cancer is that leukemias, lymphomas and many solid tumors also display a calreticulin 'eat me' signal," said Irving Weissman, director of the Stanford Institute for Stem Cell Biology and Regenerative Medicine.

"The research also shows that most normal cell populations don't display calreticulin and are therefore not depleted when we expose them to a blocking anti-CD47 antibody," Weissman said.

The researchers also found that the most aggressive cancers were the ones making the most CRT.

The study has been published Dec. 22 in Science Translational Medicine. (ANI)