Neural Stem Cells in the Adult Subventricular Zone Oxidize Fatty Acids to Produce Energy and Support Neurogenic Activity.

Neural activity is tightly coupled to energy consumption, particularly sugars such as glucose. However, we find that, unlike mature neurons and astrocytes, neural stem/progenitor cells (NSPCs) do not require glucose to sustain aerobic respiration. NSPCs within the adult subventricular zone (SVZ) express enzymes required for fatty acid oxidation and show sustained increases in oxygen consumption upon treatment with a polyunsaturated fatty acid. NSPCs also demonstrate sustained decreases in oxygen consumption upon treatment with etomoxir, an inhibitor of fatty acid oxidation. In addition, etomoxir decreases the proliferation of SVZ NSPCs without affecting cellular survival. Finally, higher levels of neurogenesis can be achieved in aged mice by ectopically expressing proliferator-activated receptor gamma coactivator 1 alpha (PGC1α), a factor that increases cellular aerobic capacity by promoting mitochondrial biogenesis and metabolic gene transcription. Regulation of metabolic fuel availability could prove a powerful tool in promoting or limiting cellular proliferation in the central nervous system. Stem Cells 2015;33:2306-2319.

Usage of epidermal growth factor mutation testing and impact on treatment patterns in non-small cell lung cancer: An international observational study.

OBJECTIVES: Epidermal growth factor receptor (EGFR) mutations (EGFRm) are common oncogene drivers in non-small cell lung cancer (NSCLC). This real-world study explored treatment patterns and time to receive EGFRm test results in patients with advanced EGFRm NSCLC. METHODS: A cross-sectional medical chart review was completed May-August 2020 in Australia, Canada, Germany, Italy, South Korea, Taiwan, UK, and USA. Eligible patients had advanced NSCLC and a positive EGFRm test result January-December 2017. Data were abstracted from NSCLC diagnosis to end of follow-up (31 March 2020) or patient's death whichever occurred earlier. The index date was the date of EGFRm confirmation. RESULTS: 223 physicians provided data for 1,793 patients. Patients' mean age was 64.7 years, 54 % were male, 30.7 % had no history of smoking. Overall, 78 % of EGFRm test results were received ≤ 2 weeks after request (range of median 7-14 days across countries). Median time from advanced NSCLC diagnosis to EGFRm test result was 18 days (median range 10-22 days across countries). Over a third (37 %) of patients received a systemic treatment prior to EGFRm result; chemotherapy (25 %) and EGFR-TKI (15 %) were most commonly prescribed; post-EGFR test-result was EGFR-TKI (68 %); 80 % of patients initiated EGFR-TKI at any time point post-NSCLC diagnosis. Of those receiving a first-line EGFR-TKI post-EGFRm testing, 84 % received a TKI alone, 12 % in combination with chemotherapy, and 3 % with other treatments. Median time from first-line EGFR-TKI initiation post-EGFRm testing to first subsequent treatment was 19.8 months. CONCLUSION: Over one-fifth of patients wait >14 days for their EGFRm test results, affecting their likelihood of receiving first-line EGFR-TKI with 20 % of patients never receiving EGFR TKI treatment. There was significant inter-country variability in the proportion of patients receiving EGFR TKIs. Our study highlights the need to improve EGFRm testing turnaround times and treatment initiation across countries.