Study Discovers New Breast Cancer Treatment Target

Breast Cancer Treatment

A new study, conducted by researchers from the Friedrich Miescher Institute for Biomedical Research shows that a group of proteins called phosphatase SHP2 are involved in growth and dissemination of breast cancers with poor prognosis. This study was published in the latest issue of nature Medicine and highlights the important role of SHP 2 in breast cancer development,  being able to maintain viable and active tumor initiating cells which are responsible for tumor development, metastasis and cancer relapse.

Tumor initiating cells represent a group of cells that can initiate cancer growth, make some cancer types to become resistant to therapies or can cause relapse. In latest years this family of cells are extensively studied by researchers because they are thought to be responsible for resistance to chemotherapy in some types of cancer and for early relapse after targeted therapy. It was also observed that tumor initiating cells predominate in aggressive and refractory forms of cancer. Until now, knowledge about the way how this cells promote cancer growth and inter-cellular pathways used by this cells to determine metastasis and relapse was not available and studies in this direction are only at the beginning.

With this study, scientists were able to demonstrate that in the developing of aggressive forms of breast cancer  a series of signaling proteins that are holding the capacity to activate tumor initiating cells are involved. This signaling proteins called phosphatase SHP2 are involved in breast cancer proliferation, invasion and metastasis. The discovery was made after researchers depleted SHP2 from malignant cells using small RNA sequences when proliferation and invasion of breast cancer cells has decreased and the tumor growth was blocked, thus reducing metastasis. It was also observed that SHP2 depletion lowers the number of tumor initiating cells .

“We believe that one should not only target the bulk of the tumor but also the tumor initiating cells. By better understanding the signaling events governing tumor initiating cells, we hope to develop new, more efficacious, therapeutic approaches.”, researchers said.

After depleting SHP2 proteins, researchers noticed that this phosphatase is actually using intracellular pathways that activate transcription factors associated with stem cells proliferation. SHP2 proteins are encoded by a series of genes called “signature genes” that are over-expressed in breast cancer with poor prognosis and invasive behavior.

The discovery of signature genes which are over-expressed by SHP2 proteins has an important clinical impact as it allows scientists to identify breast cancers with high levels of SHP2 proteins, tumors which can be treated with SHP2 targeted therapy.

This study highlights the critical role of SHP2 proteins in activation of tumor initiating cells which are associated with rapid growth, early invasion and metastasis of breast cancers with poor prognosis. In the near future, scientists hope be able to develop tests which can detect aggressive forms of cancers in its early stages and also develop SHP2-targeted therapies.