What's 'cancer cachexia' syndrome, a disease behind most patients' death?
When tumours in cancer patients elevate levels of an immune system molecule called Interleukin-6 (IL-6), it can cause severe brain dysfunction, which leads to a lethal wasting disease called 'cachexia' in about 50 to 80 per cent of cancer patients, a new study said on Monday.
As per US-based Cold Spring Harbor Laboratory's (CSHL) Professor Bo Li, "It’s a very severe syndrome".
"Most people with cancer die of 'cachexia' instead of cancer. And once the patient enters this stage, there’s no way to go back because essentially there’s no treatment," he said in a study published in the journal Nature Communications.
Li and other researchers in the team found that blocking 'IL-6' from binding to neurons in a part of the brain called the area postrema (AP) prevents cachexia in mice.
As a result, the mice live longer with healthier brain function.
"Future drugs targeting these neurons could help make cancer cachexia a treatable disease," the researchers suggested.
In healthy patients, 'IL-6' plays a vital role in natural immune response. The molecules circulate throughout the body. When they encounter a possible threat, they alert the brain to coordinate a response.
According to the researchers, cancer disrupts this process as too much IL-6 gets produced, and it begins binding to AP neurons in the brain.
"That leads to several consequences. One is animals and humans alike will stop eating. Another is to engage this response that leads to the wasting syndrome," Li said.
The team took a two-pronged approach to keeping elevated IL-6 out of the brain in mice. Their first strategy neutralised IL-6 with custom antibodies. The second used CRISPR to reduce the levels of IL-6 receptors in AP neurons. Both tactics produced the same results -- the mice started eating again, stopped losing weight, and lived longer, the study noted.
"The brain is so powerful in regulating the peripheral system. Simply changing a small number of neurons in the brain has a profound effect on whole-body physiology. I knew there was an interaction between tumours and brain function, but not to this extent," said Li.