Neuro-Signals from Gut Microbiota: Perspectives for Brain Glioma Author: Giuseppina D&#39;Alessandro1,2, Clotilde Lauro1, Deborah Quaglio3, Francesca Ghirga3, Bruno Botta3, Flavia Trettel1, Cristina Limatola2,4 Affiliation: <sup>1</sup> Department of Physiology and Pharmacology, Sapienza University, 00185 Rome, Italy. <sup>2</sup> IRCCS Neuromed, 86077 Pozzilli, IS, Italy. <sup>3</sup> Department of Chemistry and Technology of Drugs, &quot;Department of Excellence 2018-2022&quot;, Sapienza University, P.le Aldo Moro 5, 00185 Rome, Italy. <sup>4</sup> Department of Physiology and Pharmacology, Sapienza University, Laboratory Affiliated to Istituto Pasteur Italia, 00185 Rome, Italy. Conference/Journal: Cancers (Basel) Date published: 2021 Jun 4 Other: Volume ID: 13 , Issue ID: 11 , Pages: 2810 , Special Notes: doi: 10.3390/cancers13112810. , Word Count: 172 Glioblastoma (GBM) is the most aggressive form of glioma tumor in adult brain. Among the numerous factors responsible for GBM cell proliferation and invasion, neurotransmitters such as dopamine, serotonin and glutamate can play key roles. Studies performed in mice housed in germ-free (GF) conditions demonstrated the relevance of the gut-brain axis in a number of physiological and pathological conditions. The gut-brain communication is made possible by vagal/nervous and blood/lymphatic routes and pave the way for reciprocal modulation of functions. The gut microbiota produces and consumes a wide range of molecules, including neurotransmitters (dopamine, norepinephrine, serotonin, gamma-aminobutyric acid [GABA], and glutamate) that reach their cellular targets through the bloodstream. Growing evidence in animals suggests that modulation of these neurotransmitters by the microbiota impacts host neurophysiology and behavior, and affects neural cell progenitors and glial cells, along with having effects on tumor cell growth. In this review we propose a new perspective connecting neurotransmitter modulation by gut microbiota to glioma progression. Keywords: cell proliferation; glioma; gut-brain axis; microbiota; neurotransmitters. PMID: 34199968 DOI: 10.3390/cancers13112810