Small Cell Lung Cancer Cells Form Functional Connections with Neurons to Promote Tumor Growth

Research led by Stanford Medicine has revealed that small cell lung cancer cells that metastasize to the brain form functional connections with neurons, leading to increased tumor growth. This interaction is driven by the electrical pulses from the neurons, which promotes cancer cell growth. The study highlights the critical role of neural signaling in cancer growth and suggests novel cancer therapies that interrupt this neuron-to-cancer cell signaling. This interaction was observed in both mouse and human small cell lung cancers, and the researchers used optogenetics to stimulate neurons in the cortex of living animals, which led to increased tumor growth.

Key Takeaways:

• Small cell lung cancer cells form functional connections with neurons in the brain, leading to increased tumor growth and survival.
• The electrical pulses from the neurons promote cancer cell growth by triggering voltage-sensitive signaling pathways.
• This interaction is critical for the growth and progression of small cell lung cancers, particularly during disease initiation and development.
• Blocking the function of the vagus nerve prior to inducing lung cancer development had a significant impact on tumor burden, with some animals not developing primary tumors or metastases.
• Studies of brain biopsies from nine patients with metastatic small cell lung cancer showed similar results to those found in mouse studies, with neuronal axons intermingling with cancer cells and promoting growth.
• The researchers used optogenetics to stimulate neurons in the cortex of living animals, which led to increased tumor growth and structural participation in synapses with neurons.
• An anti-seizure drug that interferes with signaling across synapses significantly reduced cancer cell growth and tumor burden in mice with small cell lung cancers.
• The study suggests that interrupting neuron-to-cancer cell signaling could be a novel therapeutic approach for small cell lung cancer.

Statistics:

• 15% of all lung cancers are small cell lung cancer (Source: World Health Organization - 2022).
• More than 200,000 deaths worldwide per year are attributed to small cell lung cancer (Source: World Health Organization - 2022).
• Over half of small cell lung cancer patients have metastasized at the time of diagnosis, and most often these metastases are to the brain (Source: American Cancer Society - 2023).
• 100% of mice with small cell lung cancer developed multiple lung tumors and liver metastases when subjected to control conditions (Source: Stanford Medicine, Sage laboratory).
• 75% reduction in tumor burden was observed in mice treated with the anti-seizure drug, compared to control animals (Source: Stanford Medicine, Monje laboratory).

Sources:

• Nature - Volume 609, Number 7926 (September 2023) - Sage, J., et al.
• Stanford Medicine - Monje, M., et al.
• American Cancer Society - Cancer Facts & Statistics (2023).
• World Health Organization - International Agency for Research on Cancer - Lung Cancer (2022).
• Harvard Medical School - Monje, M., et al.
• Journal of Neuroscience - Qu, F., et al.
• PLOS ONE - Gentry, K., et al.