The discovery by U.S. biologists may help develop new ways to eliminate leukemia metastases in the nervous system and improve the effectiveness of treatments for this form of cancer.

A team of molecular biologists in the United States has found that copper ions play a key role in the survival and proliferation of acute lymphoblastic leukemia cells after they enter the brain and central nervous system. The findings were published in the journal *Nature Cancer*.

According to the researchers, the spread of cancer cells into cerebrospinal fluid typically leads to severe complications in most types of tumors. In acute lymphoblastic leukemia, such metastases are often controlled with chemotherapy, but in some cases treatment is ineffective and may increase the risk of cognitive impairment in children.

To better understand how tumor cells adapt to the central nervous system environment, the scientists led by Harvard University associate professor Naama Kanarek studied their behavior in cerebrospinal fluid, which contains extremely low levels of nutrients. They also conducted experiments in immunocompromised mice, introducing leukemia cells into the brain and tracking their spread as well as genetic changes linked to metabolism.

The experiments showed that the SLC31A1 gene and other copper-transport mechanisms are essential for tumor cell survival. Damage to these pathways disrupts energy metabolism and reduces the cells’ ability to divide and produce DNA building blocks.

Based on these findings, the researchers tested copper-depleting compounds both in cell cultures and in animal models. Mice were also placed on a low-copper diet. In all cases, reduced copper availability slowed tumor growth, suggesting a potential way to enhance current therapies.

Acute lymphoblastic leukemia is one of the most common forms of blood cancer in young children. Although current treatments are highly effective in most cases, some patients experience relapse with involvement of the brain and other organs.