Investigators profile a lethal tumor cell that could spur metastasis

A team of investigators believe they've come up with a convincing profile for a particular type of tumor cell that could be used as a biomarker for diseases progression as well as a target for drug developers looking to identify a next-gen therapeutic.

Andreas Trumpp, a stem cell expert at the Heidelberg Institute for Stem Cell Technology and Experimental Medicine, says that his team used mouse models with a compromised immune system to identify the kind of circulating tumor cell in breast cancer patients that is most likely to trigger metastasis; the advance of cancer into other organs. They came up with a "triple positive" cell that includes the protein CD44 on the surface, which helped it settle into bone marrow, the signaling molecule CD47 that protected it from attacks by the immune system, and MET, which spurs cell migration.

In patients, says the investigator, these circulating tumor cells accounted for anywhere from 0.6% to 33% of all CTCs.

"We were convinced that only very few of the various circulating tumor cells are capable of forming a secondary tumor in a different organ, because many patients do not develop metastases even though they have cancer cells circulating through their blood," says Trumpp. Now that hypothesis will have to be tested in further studies, but Trumpp and his colleagues note that developers are already actively working on new drugs that target CD47 and MET.

"The triple-positive cells we have found turn out to be not only a promising biomarker of disease progression in breast cancer but also a prospect for potential new therapeutic approaches for treating advanced breast cancer," says Trumpp.

- here's the press release