Sympathetic Neurons Promote Small Cell Lung Cancer Through the Beta-2 Adrenergic Receptor

The vagal nerve is linked to tumorigenesis in multiple tissues including small cell lung cancer (SCLC). However, the role of sympathetic neuron in SCLC development remains unknown. Here, we observed a significant reduction in tumor growth following chemical denervation of local sympathetic nerves in a mouse model of SCLC. Further study identified that β2-adrenergic receptor (ADRB2) on cancer cells mediated the crosstalk with nerve fibers. Genetic deletion or pharmacological inhibition of ADRB2 led to reduced tumor growth and improved survival. Moreover, blocking ADRB2 also reduced the growth of human SCLC organoids and xenografts. Further studies revealed that ADRB2 promoted cancer cell expansion through activating Protein Kinase A (PKA) signaling. Consistently, inhibition of PKA also reduced the growth of SCLC cells. These findings offer the initial insight into the role played by sympathetic neurons in the development of SCLC and may open a new therapeutic avenue to treat this deadly malignancy.