Science News
from research organizations

New approach mimicking the body's natural defenses could help treat a therapy-resistant breast cancer

Date:
February 7, 2013
Source:
Weizmann Institute of Science
Summary:
A new combination of antibodies was found to be effective in mice against triple-negative breast cancer.
Share:
       
FULL STORY

Cancer drugs of the new, molecular generation destroy malignant breast tumors in a targeted manner: They block characteristic molecules on tumor cells -- receptors for the hormones estrogen or progesterone, or a co-receptor, called HER2, that binds to many growth factors. But about one in every six breast tumors has none of these receptors. Such cancers, called triple-negative, are particularly aggressive and notoriously difficult to treat.

Some of these therapy-resistant cancers have a potential molecular target for cancer drugs, a growth-factor receptor called EGFR, but an EGFR-blocking drug has proved ineffective in treating them. In a study published recently in the Proceedings of the National Academy of Sciences, Weizmann Institute researchers propose a potential solution: to simultaneously treat triple-negative breast cancer with two EGFR-blocking antibodies instead of one. In a study in mice, the scientists showed that a certain combination of two antibodies indeed prevented the growth and spread of triple-negative tumors. The research team, led by Prof. Yosef Yarden of the Biological Regulation Department and Prof. Michael Sela of the Immunology Department, included Drs. Daniela Ferraro, Nadège Gaborit, Ruth Maron, Hadas Cohen-Dvashi, Ziv Porat and Fresia Pareja, and Sara Lavi, Dr. Moshit Lindzen and Nir Ben-Chetrit.

Of the different combinations they tried, the scientists found that the approach worked when the two antibodies bound to different parts of the EGFR molecule. The combined action of the antibodies was stronger than would have been expected by simply adding up the separate effects of each. Apparently, the use of the two antibodies created an entirely new anti-cancer mechanism: In addition to blocking the EGFR and recruiting the help of immune cells, the antibodies probably overwhelmed the EGFR by their sheer weight, causing it to collapse inward from the membrane into the tumor cell.

Deprived of EGFR on its surface, the cells were no longer receiving the growth signals, preventing the growth of the tumor. This approach resembles the natural functioning of the immune system, which tends to block essential antigens at several sites by targeting them with multiple antibodies.

If supported by further studies, the two-antibody approach, in combination with chemotherapy, might in the future be developed into an effective treatment for triple-negative breast cancer.


Story Source:

The above post is reprinted from materials provided by Weizmann Institute of Science. Note: Materials may be edited for content and length.


Journal Reference:

  1. D. A. Ferraro, N. Gaborit, R. Maron, H. Cohen-Dvashi, Z. Porat, F. Pareja, S. Lavi, M. Lindzen, N. Ben-Chetrit, M. Sela, Y. Yarden. Inhibition of triple-negative breast cancer models by combinations of antibodies to EGFR. Proceedings of the National Academy of Sciences, 2013; 110 (5): 1815 DOI: 10.1073/pnas.1220763110

Cite This Page:

Weizmann Institute of Science. "New approach mimicking the body's natural defenses could help treat a therapy-resistant breast cancer." ScienceDaily. ScienceDaily, 7 February 2013. <www.sciencedaily.com/releases/2013/02/130207074256.htm>.
Weizmann Institute of Science. (2013, February 7). New approach mimicking the body's natural defenses could help treat a therapy-resistant breast cancer. ScienceDaily. Retrieved July 30, 2015 from www.sciencedaily.com/releases/2013/02/130207074256.htm
Weizmann Institute of Science. "New approach mimicking the body's natural defenses could help treat a therapy-resistant breast cancer." ScienceDaily. www.sciencedaily.com/releases/2013/02/130207074256.htm (accessed July 30, 2015).

Share This Page: