Project description:Neural activity is increasingly recognized as a crucial regulator of cancer growth. In the brain, neuronal activity robustly influences glioma growth both through paracrine mechanisms and through electrochemical integration of malignant cells into neural circuitry via neuron-to-glioma synapses. Outside of the CNS, innervation of tumors such as prostate, breast, pancreatic and gastrointestinal cancers by peripheral nerves similarly regulates cancer progression. However, the extent to which the nervous system regulates small cell lung cancer progression, either in the lung or when growing within the brain, is less well understood. Small cell lung cancer (SCLC) is a lethal high-grade neuroendocrine tumor that exhibits a strong propensity to metastasize to the brain. Here we demonstrate that SCLC cells in the brain co-opt neuronal activity-regulated mechanisms to stimulate growth and progression. In the lung, vagus nerve transection markedly inhibits primary lung tumor formation and development, highlighting a critical role for innervation in SCLC growth. In the brain, glutamatergic and GABAergic cortical neuronal activity each drive proliferation of SCLC in the brain through both paracrine and synaptic neuron-cancer interactions. SCLC cells form bona fide neuron-to-SCLC synapses and exhibit depolarizing currents with consequent calcium transients in response to neuronal activity. SCLC cell membrane depolarization is sufficient to promote the growth of intracranial tumors. Taken together, these studies illustrate that neuronal activity plays a crucial role in dictating SCLC pathogenesis in both the lung and the brain.
Project description:Neural activity is increasingly recognized as a crucial regulator of cancer growth. In the brain, neuronal activity robustly influences glioma growth both through paracrine mechanisms and through electrochemical integration of malignant cells into neural circuitry via neuron-to-glioma synapses. Outside of the CNS, innervation of tumors such as prostate, breast, pancreatic and gastrointestinal cancers by peripheral nerves similarly regulates cancer progression. However, the extent to which the nervous system regulates lung cancer progression, either in the lung or when metastatic to brain, is less well understood. Small cell lung cancer (SCLC) is a lethal high-grade neuroendocrine tumor that exhibits a strong propensity to metastasize to the brain. Here we demonstrate that SCLC cells in the brain co-opt neuronal activity-regulated mechanisms to stimulate growth and progression. Glutamatergic and GABAergic cortical neuronal activity each drive proliferation of SCLC in the brain through both paracrine and synaptic neuron-cancer interactions. In the brain, SCLC cells form bona fide neuron-to-SCLC synapses and exhibit depolarizing currents with consequent calcium transients in response to neuronal activity. SCLC cell membrane depolarization is sufficient to promote the growth of intracranial tumors. In the lung, vagus nerve transection markedly inhibits primary lung tumor formation and development, highlighting a critical role for innervation in overall SCLC growth. Taken together, these studies illustrate that neuronal activity plays a crucial role in dictating SCLC pathogenesis in both the lung and the brain.
Project description:The GGGGCC nucleotide repeat expansion (NRE) mutation in the C9orf72 (C9) gene is the most common cause of ALS and FTD. Neuronal activity plays an essential role in shaping biological processes within both healthy and neurodegenerative disease scenarios. Here, we show that at baseline conditions, C9-NRE iPSC-cortical neurons display aberrations in several pathways, including synaptic signaling and transcriptional machinery, potentially priming diseased neurons for an altered response to neuronal stimulation. Indeed, exposure to two pathophysiologically relevant stimulation modes, prolonged membrane depolarization, or a blockade of K+ channels, followed by RNA sequencing, induces a temporally divergent activity-dependent transcriptome of C9-NRE cortical neurons compared to healthy controls. These findings reveal the impact of neuronal activity on the ALS/FTD-associated transcriptome and may reveal pathways necessary for conferring neuronal resilience or degeneration.
Project description:Neuronal activity-dependent gene expression is fundamental to a wide variety of brain functions. Transcriptional profile after in vitro stimulation has been assessed using different modalities to induce neuronal activity. In this work, we first investigate the influence of development on neuronal activity and activity-driven transcription. We used an RNA sequencing approach over 7 days in vitro (DIV) or mature 21 DIV neurons after neuronal depolarization with potassium chloride (KCl)compared to Biccuculine application, a synaptic modality to induce neuronal activity. To further investigate how different activity patterns influence gene transcription in mature neurons, we performed a comparative analysis of global gene expression in neurons treated with extensively used activation protocols KCl, Bic, and TTX withdrawal. Our results demonstrate that different patterns of neuronal activity not only induce different transcriptional profiles but also exhibit distinct temporal dynamics for the same genes. These findings offer novel insights into the complex relationship between neuronal activity and gene expression, shedding light on the context-dependent nature of activity-dependent transcriptional responses.