Anaplastic astrocytoma (AA) is a rare, malignant brain tumor that arises from astrocytes, the supportive cells in the nervous system. Anaplastic astrocytomas (grade III) may also be called a “grade III glioma” or “high-grade glioma.” Symptoms of anaplastic astrocytoma can result from an increase of pressure in the brain. This occurs as the tumor grows larger and takes up space, compressing healthy brain tissue within the fixed volume of the skull. If not diagnosed early, tumors can grow large enough to block the normal flow of cerebrospinal fluid in the brain [1]. In this study, the regulation of GPR45 gene and the effect of lncRNA-CYTOR on it in anaplastic astrocytoma were examined using bioinformatics databases. Methods Conclusions The 2nd International Conference on Biotechnology and Global Development Investigate the relation between GPR45 gene and lncRNA-CYTOR in anaplastic astrocytoma Elnaz Nasiriyan1, Negar Amidi, Ali Attaripour Isfahani1, Tahereh Sadeghian-Rizi2,* 1 Department of Biological Science and Technology, Najafabad Branch, Islamic Azad University, Najafabad, Iran 2,* Department of Biotechnology, Faculty of Biological Sciences and Technology, Shahid Ashrafi Esfahani University, Isfahan, Iran Bibliography First, this gene was structurally analyzed in GeneCards then GPR45-related single nucleotide polymorphisms (SNPs) and microRNAs were found in GWAS Catalog and NCBI databases. Ultimately, the LncRNADisease database (version 2.0) helped to find a long non-coding RNA (lncRNA) connected with the GPR45 gene signaling pathways. [1] M. Caccese, M. Padovan, D. D'Avella, F. Chioffi, M.P. Gardiman, F. Berti, F. Busato, L. Bellu, E. Bergo, M. Zoccarato, M. Fassan, V. Zagonel, G. Lombardi, Anaplastic Astrocytoma: State of the art and future directions, Crit. Rev. Oncol. Hematol, 153(2020), 103062. The GPR45 gene, which encodes a member of the G protein-coupled receptor (GPCR) family and is located on chromosomal position 2q12.1, mediate signaling processes to the interior of the cell via activation of heterotrimeric G proteins. According to findings from the GEPIA2 database, the GPR45 gene is highly expressed in astrocytoma. The analysis Indicated that the incidence of the SNP:rs2576789 can lead the cells to Anaplastic astrocytoma and outcome the involved miRNA- 4435-1 and lncRNA-CYTOR in this process. Through the process of this disease, the disease- associated SNP is located on the mRNA and the miRNA-4435-1 binds to 3’UTR of GPR45 mRNA as an activator. When lncRNA-CYTOR, binds to miRNA-4435-1, turns on miRNA- 4435-1 and the GPR45 gene is activated, finally intensifies the tumorigenesis of anaplastic astrocytoma. The present study inferred that, the interaction of lnc-CYTOR with rs2576789 could be useful biomarkers for the diagnosis of anaplastic astrocytoma. The miRNA-4435-1 proves also that GPR45 is an effective gene in anaplastic astrocytoma outbreak and its tumorigenesis, so there is hope for early diagnosis this malignant brain tumor. Introduction Results Anaplastic Astrocytoma Normal astrocytes Different parts of the brain tissue 0 1 2 3 4 5 6 Other brain diseases Anaplastic astrocytoma miR-4435-1 Up Regulated Down Regulated Figure1: Anaplastic Astrocytoma Diagram1: GPR45 gene expression level in different tissues of the human body. Diagram2: GPR45 gene expression level in anaplastic astrocytoma and other brain diseases. Figure2: The volcanic map of identification of significantly expressed miRNA in Anaplastic Atrocytoma. The red dots represent significantly up-regulated miRNAs and the green dots represent significantly down- regulated miRNAs. miRNA volcano