Antibody Cancer Marker Causes Tumors to Light Up

A novel marker attaches to a molecule on highly aggressive brain cancer, resulting in glioblastoma tumor tissue being easily identified in a positron emission tomography (PET) scanner.

Developed by researchers at the University of Wisconsin (WISC; Madison, USA) and the Third Military Medical University (Chongqing, China), the antibody created is specific to a unique protein, called CD146, that is present on the surface of glioblastoma multiforme cancer cells; the antibody was joined to a copper isotope to create a radio-labeled anti-CD146 antibody (YY146). The researchers then implanted a human glioblastoma sample into a mouse and injected the antibody-marker combination into its blood, waiting for it to spread through the body.

When the mouse was later placed into a PET scanner, the tumors with a high level of CD146 protein on the outside of their cells were easily identified. In comparison, signals from a genetically distinct variant of glioblastoma with low CD146 activity were much weaker. In their study, the researchers also explored the potential therapeutic effects of YY146 on cancer stem cell (CSC) and epithelial-to-mesenchymal (ETM) properties of glioblastoma cells, demonstrating that it can mitigate aggressive U87MG phenotypes.

The researchers also demonstrated that YY146 could be used to detect CD146 in cancer cell lines and human resected tumor tissues of multiple other origins, such as in gastric, ovarian, liver, and lung tissues. These findings, according to the researchers, indicate a broad applicability of the YY146 marker in solid tumors, including for diagnosis, stratification, and targeted therapy. The study was published on November 9, 2015, in Proceedings of the National Academy of Sciences of the United States of America (PNAS).

“Most methods generate antibodies that recognize short fragments of the target protein, whereas our antibody recognizes the target in the biologically active form. So the antibodies can be readily used in living subjects, such as the animal models in this study and potentially in patients,” said senior author associate professor of radiology Weibo Cai, PhD, of WISC. “If the technique proves out in further tests, it could be used to diagnose some strains of aggressive glioblastoma, and also to evaluate treatment progress or even to test potential drugs.”

Related Links:
University of Wisconsin
Third Military Medical University