London, Thanasis Gavos

Researchers at the Institute of Cancer Research London have found that a particular protein plays a critical role in whether the most common type of breast cancer, known as ER+, will metastasize to the lung.

The researchers studied this particular condition because, unfortunately, this type of metastatic cancer occurs frequently, with the risk of it persisting for decades after the primary appearance of the breast tumor.

This cancer “time bomb”, as described in the study published in the journal Nature Cancer, is attributed to the protein PDGF-C. It is a protein necessary for the growth and survival of cell tissues.

When levels of this protein increase, which happens as we age or when there is damage or injury to lung tissue, it is possible to activate dormant cancer cells in the lung.

After establishing this causal link with regard to metastatic cancer with studies in mice in the laboratory, the researchers sought to see if blocking the protein’s action could prevent the activation of the cancer.

The use in mice of the drug imatinib, which is administered to patients with chronic myeloid leukemia, returned encouraging results in this direction. Specifically, the development of cancerous tumors in the lung was significantly reduced both in mice that received the drug before the onset of cancer and in those that were given the drug after the appearance of the metastatic tumor.

The author of the research, Dr. Frances Tarell, said that it is important to discover both the mechanism of “waking up” cancer cells, and how to “defuse” the metastatic time bomb.

“We now plan to reveal more clearly how patients could benefit from the existing drug imatinib, and in the longer term we aim to create more targeted therapies for the ‘awakening’ mechanism,” added the British researcher.