Washington, August 04: Researchers said on Monday they had found primitive bladder cancer cells that cloak themselves with a “don’t eat me” signal that scares off immune system cells, allowing them to mature into tumours later on.
But they found a way to unmask this disguise and said their findings may lead to new approaches for treating cancers of several different types.
The immediate hope is to find a way of telling apart patients who have dangerous bladder cancer from those who have more benign forms. Bladder cancer is mostly slow-growing and easily treated, but 15% of cases become invasive and deadly.
Dr Irving Weissman of Stanford University in California and colleagues found that the so-called cancer stem cells disguise themselves using a protein called CD-47. Immune system cells called macrophages usually eat cancer cells but CD-47 is a signal that turns them off.
“This is first time we’ve found this ‘don’t eat me signal’ in a stem cell of a solid cancer,” Weissman said in a statement. “We’re now moving as fast as we can to look at other tumors to see if this is a universal strategy of all or most cancer stem cells.”
The same team earlier found that some types of leukemia cells also use CD-47 as a disguise. Samples from bladder tumours showed that most were rich in CD-47.
—Agencies