A new therapeutic outlook for metastatic breast cancer
So-called ER+ (estrogen receptor positive) breast cancers - which have female hormone receptors in the estrogen family - are by far the most common breast tumors, accounting for around 80% of breast cancers. Generally speaking, patients can receive effective hormone treatments thanks to these receptors, but some women are unfortunately resistant to these medications. They can then suffer relapse, frequently with metastases in the bone, which is particularly painful and even more difficult to treat. This is why Elisabetta Marangoni - a researcher at Institut Curie - wanted to study these specific tumors more closely.
“I was able to collaborate closely with the surgeon, the oncologists and the pathologists who treat these patients for access to the tumor material,” she explains. She and her team were the first in the world to design preclinical models of bone metastases of these cancers. They can now study these models and multiply them in the lab, and can use them to test drugs.
Elisabetta Marangoni demonstrated that an enzyme known as PLK1 - already well known for its role in cell proliferation - was particularly abundant in these treatment-resistant metastases. She then tested a PLK1 inhibitor on these models and found that the tumors regressed, in some cases even disappearing completely. Significantly, the PLK1 inhibitor is also highly effective in tumors with acquired resistance to Palbociclib, a cell cycle inhibitor recently approved for treating breast cancer.
Through ongoing exchanges between Institut Curie’s hospital and the research center, a clinical trial should soon be set up so that patients can benefit from this promising therapeutic strategy as soon as possible.