Dr. Marina Holz, The Doris and Ira Kukin Professor of Biology at Stern College for Women, co-authored a research paper with scientists from the Linköping University and the Karolinska Institute in Sweden as well as with Dr. Anya Alayev ’03S, ’10E, clinical assistant professor of biology, and Adi Berman ’16s, currently a PhD student in the Tri-Institutional Program in Chemical Biology, run by Rockefeller University, Weill Cornell Medicine, and Sloan Kettering.

The paper, titled “Raptor localization predicts prognosis and tamoxifen response in estrogen receptor positive breast cancer,” continues Holz’s investigation into a cellular signaling pathway called mTOR, which plays a critical role in breast cancer by promoting tumor growth and making the tumors resistant to endocrine (anti-estrogen) treatment. They have previously found in a paper published in Oncogene that mTOR regulates the response of breast cancer cells to the hormone estrogen.

In this paper, the authors investigated how the cellular location of the protein called raptor, which binds mTOR and serves as its adaptor, contributes to disease severity and response to tamoxifen. The researchers were able to show that raptor’s subcellular presence in the cytoplasm or the nucleus of tumor cells correlates with the effectiveness of the tamoxifen treatment in a cohort of breast cancer patients.

This study is a continuation of the collaboration between the Holz lab and the two groups in Sweden. The team has previously published a study investigating the response to tamoxifen in another sub-type of breast cancer called triple-negative breast cancer. “Science is a collaborative international undertaking. In order to find solutions to complex problems like breast cancer, researchers from different career stages, scientific fields and countries need to work together,” said Holz.