Venkataramani, V. et al. Nature 573, 532–538 (2019).

Venkatesh, H. S. et al. Nature 573, 539–545 (2019).

Zeng, Q. et al. Nature 573, 526–531 (2019).

Neurons form excitatory synapses with brain tumor cells, and this direct neural circuit input promotes tumor growth.

Gliomas, a type of brain tumor, depend upon neuronal activity for growth. Although indirect interactions between neurons and brain tumor cells have been previously described, it was unclear whether direct synaptic electrochemical signaling contributed to tumor progression.

In two separate studies, Michelle Monje and colleagues, and Thomas Kuner, Frank Winkler and colleagues provide evidence for the formation of functional synapses between neurons and glioma cells in xenograft mouse models as well as in human glioma tissue. In a third study, Douglas Hanahan and colleagues show that glutamate secreted by neurons mediates the colonization of brain metastases in a mouse model and that such glutamatergic signaling is active in human brain metastases.