A group of researchers from the University of Melbourne (Australia) found that stress hormones increase the spread of cancer by affecting the lymphatic system, a network of blood vessels that carries a fluid called lymph throughout the body.
According to an experiment in mice published today in the British journal Nature, there is evidence confirming that stress is associated with increased mortality in patients with cancer and advanced levels of this disease in animals.
Earlier work had found that stress hormones can affect the formation of blood, major vessels in the spread of diseases.
The lymphatic system can also encourage the spread of cancer, but until now it was unclear whether this was due to stress.
The researcher Erica Sloan and his colleagues at the University of Melbourne revealed that stress hormones affect the lymphatic system, and this can lead to the spread of cancer cells in mice.
They studied five rodents through a series of experiments from which demonstrated that stress increases both the number and the diameter of lymphatic vessels associated with tumors.
Through a special microscope, the authors found that stress hormones increase the flow of fluorescent nanoparticles (localizing tumor cells) via the lymphatic system.
By blocking the activity of proteins that detect stress or those that facilitate the formation of lymphatic vessels, scientists were able to reduce the spread of cancer cells in mice.
This new discovery, scientists may be useful to help curb the spread of cells that can develop an oncological disease.