Study Finds Tumors Manipulate Nearby Neurons to Fuel Growth
A recent study reveals that tumors can enhance their growth by attracting nearby sensory neurons. These neurons, when they connect with the tumor cells, send signals to the brain that effectively dampen the immune response aimed at destroying the cancer cells, allowing them to grow unhindered.
Published in Nature, the research identified a specific pathway that facilitates communication between the tumor and the brain in mice with lung cancer. Anna-Maria Globig, a cancer immunologist at the Allen Institute for Immunology in Seattle, remarked, “The tumor hijacks the signalling axis and uses it for its own purpose.”
The researchers took significant steps: by genetically manipulating the sensory neurons, they were able to “knock out” their function, which resulted in an impressive reduction of tumor growth—over 50%, according to co-author Chengcheng Jin from the University of Pennsylvania.
Understanding Neuronal Connections
For quite some time, scientists have acknowledged the presence of nerve cells within tumors. “We know that nerves are there,” said Moran Amit, a head and neck surgeon at the University of Texas. However, deciphering the impact of these neurons on tumor sustainability has posed challenges.
One possible reason for this difficulty is that the tools to analyze neuronal activity have not always been sufficiently advanced. Additionally, the structure of neurons complicates matters; their DNA and RNA are primarily situated in cell bodies that are often distant from their branched extensions, known as dendrites, which infiltrate tumors. This distance means collecting genetic data during tumor biopsies is quite tough. Timothy Wang, a gastroenterologist at Columbia University, pointed out that the peripheral nervous system is an area previously overlooked in cancer research.
Jin and her team had observed through microscopy that neurons enveloped and intruded into lung tumors. They hoped that by disabling specific neurons—using either genetic or pharmacological methods—they could observe changes in tumor growth rates. “We spent almost a year trying various drugs,” co-author Haohan Wei noted, but unfortunately, “there wasn’t any effect.”
