Stress linked to cancer development

A new study published in the journal Biology has reported that the fight or flight, stress response increases the rate at which the breast cancer cells spread into other organs and bones.

Metastasis is the migration of cancer cells into other organs of the body and bones. This is the most lethal form of cancer. Research that establishes what causes metastasis means that treatments that specifically target those root causes can be developed.

The researchers were building on evidence from breast cancer clinics. It had previously been found that patients who suffer from stress or depression after their primary treatment had reduced life expectancy.

Stress activates the sympathetic nervous system; it was believed that this primed the bone around the cancer cells to allow for metastasis to occur.

The researcher used mice to test their hypothesis the mice were injected with human breast cancer cells that had been dyed so that their movement around the mice could be examined. The mice were then put into different categories, some were stressed to activate their sympathetic nervous system, half of these mice were then administered ‘beta-blockers’ medication that is used to treat hypertension and suppress the sympathetic nervous system.

It was concluded that sympathetic nervous system activation increased the rate of migration of cancer cells into bone through a molecule called RANKL which causes bone cells to break down tissue. The beta-blocker drugs impede the RANKL signalling.

This means that beta-blockers could be prescribed after the primary treatment for breast cancer to restrict the spread of cancer to other organs and bone. Stress management techniques such as mindfulness offer effective, non-toxic means of reducing sympathetic nervous system activation and potentially playing the same role as beta-blockers without the cost or need to take more drugs after the primary treatment of cancer.