‘Current drugs may prevent breast cancer spreading to bones’
Tel Aviv University (TAU) researchers have developed a therapeutic strategy based on existing medications to inhibit bone metastasis in breast cancer patients. When a patient has this malignancy and it isn’t stopped from spreading, most often – in 75% of cases – it spreads to the bone, destroying its tissues and causing fractures and a great deal of pain.
Using both an animal model and tissue samples from patients in Israel and the US, the researchers showed that a combination of drugs already available on the market can hinder bone metastasis and improve survival. Based on their findings, they predict that in the future, the treatment will be applied to human patients with breast cancer as well as other types of cancer.
In this groundbreaking study, the researchers looked for a novel way to inhibit the progression of bone metastasis. The study was led by Prof. Neta Erez and Dr. Lea Monteran at Erez’s Laboratory for Tumor Biology at the pathology department of the university’s Faculty of Medical and Health Sciences. The paper has just been published in Cancer Discovery under the title “Clofazimine Reduces Side Effects from Dual Immune Checkpoint Blockade.”
With today’s technologies, such as MRI and CT imaging, a diagnosis of bone metastasis mostly occurs when the disease has already gone too far and the patient can no longer be cured.
“A tumor is more than a collection of cancer cells. Just like healthy tissues, a tumor is a whole ecosystem consisting of reciprocal interactions between different cell types, including cells of the immune system, connective tissues, blood vessels, and more. Cancer cells often ‘corrupt’ normal cells, causing them to ‘collaborate’ with the tumor and support the growth of cancer cells. Blocking the communication channels between cancer cells and healthy cells at an early stage can hinder the growth of cancer cells in the bones. To achieve this, the early stages of the process must be investigated,” Erez explained.
To understand the process of bone metastasis, the researchers compared three types of bones from model mice – healthy, early-stage metastasis, and advanced metastasis. They found that when bone metastasis begins, T cells from the immune system penetrate the metastases but are unable to destroy them.
“Our findings suggest that the combined treatment – attacking the cells that inhibit T cells while activating the T cells – can be effective for treating bone metastasis resulting from breast cancer as well as other types of cancer,” Erez said.
“The great advantage of our strategy is that both drugs are already available on the market, so the process of obtaining permits to use them against bone metastasis in humans can be relatively short. At the same time, clinical trials are needed to verify the effectiveness of the new therapeutic strategy.”