Cocktail of repurposed drugs offers hope to breast cancer patients

JERUSALEM – In a significant stride towards combating metastatic breast cancer, Israeli researchers unveiled a novel therapeutic approach utilizing already-existing medications that offers hope for improved survival rates.

Breast cancer originates in the breast tissue, typically in the milk ducts or lobules. It is known to metastasize, or travel through the bloodstream or lymphatic system and establish secondary cancerous tumors in other parts of the body. Breast cancer is one of the most common cancers to metastasize to the bones.

When breast cancer cells metastasize to the bones, they disrupt normal bone function, leading to bone pain, fractures and elevated calcium levels in the blood. It is estimated that half of all people who develop stage IV breast cancer have bone metastasis.

Tel Aviv University researchers led by Prof. Neta Erez and Dr. Lea Monteran scrutinized bone samples from model mice representing different stages of metastasis, unearthing pivotal mechanisms driving the progression of the disease — particularly the interplay between cancer cells and the body’s immune system.

The findings, published in the peer-reviewed journal, Cancer Discovery, underscore the promise of repurposing existing drugs.

“A tumor is more than a mere conglomerate of cancer cells; it constitutes an intricate ecosystem comprising diverse cell types. Understanding and intercepting the communication channels between cancer cells and healthy tissues are paramount in thwarting the progression of bone metastasis,” Erez said.

One discovery was the role of T cells, the foot soldiers of the immune system, in infiltrating bone metastases. The researchers found that the efforts of the T cells are thwarted by inhibitory immune cells, hindering their ability to eradicate cancerous cells.

Armed with this knowledge, the team devised a therapeutic cocktail of already existing drugs that neutralize the inhibitory immune cells and bolster the activity of T cells.

When administered to mice, the cocktail yielded promising results, significantly reducing bone metastases and bolstering survival rates. Subsequent analysis of tissue samples from breast cancer patients affirmed the relevance of these findings in a clinical context, suggesting broader applicability across various cancer types.

“This combined treatment strategy holds immense potential for addressing bone metastasis not only in breast cancer but also in other malignancies,” Erez said.

Importantly, both components of the therapeutic regimen are already commercially available, potentially streamlining the pathway for clinical use.

But the researchers stressed that further clinical trials are necessary. (TPS)