Researchers say they now understand how skin cancer spreads to the brain, and say they can deploy existing treatments to prevent it.
The team at Tel Aviv University set out to discover why 90 per cent of advanced stage melanoma (skin cancer) patients also develop brain secondary growths (metastases) in their brains.
They found that the skin cancer cells “recruit” cells in the brain. That discovery allowed them to use existing treatments to inhibit the spread of the cancer by up to 80 per cent.
“We expect to see metastases in the lungs and liver, but the brain is supposed to be a protected organ,” said Prof. Ronit Satchi-Fainaro of the Sackler Faculty of Medicine, who led the study.
“The blood-brain barrier keeps harmful substances from entering the brain, and here it supposedly doesn’t do the job—cancer cells from the skin circulate in the blood and manage to reach the brain.
“We asked ourselves with ‘whom’ the cancer cells ‘talk’ to in the brain to infiltrate it.”
They identified star-shaped cells called astrocytes, found in the spinal cord and brain which are responsible for homeostasis, or maintaining stable conditions.
Sign up for our free weekly newsletterSubscribe
The team found they could genetically edit the cancer cells and remove the two genes that recruited new cells, effectively halting their ability to communicate.
“These treatments succeeded in delaying the penetration of the cancer cells into the brain and their subsequent spread throughout the brain,” said Prof. Satchi-Fainaro.
“It’s important to note that melanoma metastases in the brain are very aggressive with a poor prognosis of 15 months following surgery, radiation and chemotherapy.”
She said they reached a 60 per cent to 80 per cent delay, depending on the stage of the intervention.
“We achieved the best results with the treatment conducted immediately after surgery to remove the primary melanoma, and we were able to prevent the metastases from penetrating the brain. Therefore, I believe that the treatment is suitable for the clinic as a preventive measure.”
The results were published in the scientific journal JCI Insight.