Eight out of ten cancer patients also suffer from life-threatening emaciation. A fifth even die from it. Researchers at the University of Graz have now found out why so-called cachexia occurs. The results of the international research team are published today, February 25, in the scientific journal PNAS.
Cancer tricks the immune system
Martina Schweiger from the Institute for Molecular Biosciences explains: “The fault lies in faulty communication between different cell types. These include immune cells that try to fight the cancer. In the case of cachexia patients, however, they ensure that the body loses too much fat or muscle mass. As a result, cancer therapy is no longer viable.” “But it is now clear that different cell types communicate past each other while the cancer is tricking the immune system. Our goal now is to find a way to break this vicious circle,” the researcher emphasizes.
Body itself gives the command for fat loss
If you then look at the inflammation levels in the blood or tissues of cancer, it is clear: the whole body is on the alert. Because tumors of cachexia patients send inflammatory factors into the blood, which activate the immune cells. The scavenger cells in the immune system recognize the threat. They therefore send the command to break down fat so that the body can use the energy stored in it for defense. The fat mass is broken down, but the cancer is not fought because the tumor cleverly hides from the scavenger cells.
New realization
“So the efforts are wasted in vain. The scavenger, fat and nerve cells give each other the command to break down. Meanwhile, the tumor grows undisturbed. The body becomes weaker and weaker, and therapies ultimately have to be stopped,” sums up Schweiger. The work of the scientists allows completely new insights into these processes. Until now, it was believed that the tumor itself gave the signal for fat reduction.