The family of molecules that could help diagnose — and treat — breast cancer

Proteoglycans are large molecules that are important for tissues all over the body. For example, they play key roles in the development of cartilage and blood vessels, and they can also protect against inflammation and infection. But their role in cancer is less clear: while some proteoglycans protect against cancer, others can promote tumor growth.

Now, new research led by Thomas Jefferson University researcher Renato Iozzo, MD, characterizes a pattern of proteoglycans linked to breast cancer. The results could lead to more accurate diagnostics and form the basis for new cancer treatments.

“It’s the first comprehensive study on proteoglycans in breast cancer,” Dr. Iozzo says.

The study, published in Proteoglycan Research, analyzed genetic information from over 1,000 tumor tissue samples. Using a machine learning algorithm, the researchers identified two different groups of proteoglycans: one that was present at higher levels in tumors, and one that was present at lower levels. They also found these same proteoglycans were connected to prognosis and tumor aggressiveness. Proteoglycans that promoted cell growth tended to be associated with more aggressive tumors, whereas proteoglycans that inhibited growth were associated with less malignant tumors.

Dr. Iozzo hopes these patterns could be used to develop new tests to diagnose and provide accurate prognoses for breast cancer, ultimately resulting in better personalized treatments for cancer patients. Dr. Iozzo plans to investigate if the same proteoglycans can be used as biomarkers for other types of tumors, such as those in the skin, pancreas, or colon.

“It is absolutely fundamental to have better biomarkers for breast cancer,” Dr. Iozzo, a member of Sidney Medical College, says. “This is really the beginning.”

By clarifying the role of specific proteoglycans in breast cancer, this research also acts as a jumping-off point for new treatments. In this vein, Dr. Iozzo is in the initial stages of developing an injectable proteoglycan-based drug aimed at preventing cancer from metastasizing.

By Marilyn Perkins