@misc{Pasierbińska_Maria_Syntetyczne_2024, author={Pasierbińska, Maria}, editor={Kamińska-Kaczmarek, Bożena (1961– ) : Supervisor}, editor={Ellert-Miklaszewska, Aleksandra : Assistant supervisor}, copyright={Rights Reserved - Restricted Access}, address={Warszawa}, howpublished={online}, school={Nencki Institute of Experimental Biology PAS}, school={degree obtained in 2024}, year={2024}, publisher={Instytut Biologii Doświadczalnej im. Marcelego Nenckiego PAN}, language={pol}, abstract={Malignant gliomas are the most common primary malignant brain tumors in adults. The results of experimental and clinical studies showed that these tumors are infiltrated by microglia (myeloid cells present in the brain) and bone marrow derived monocytes/macrophages. Instead of initiating an anti-tumor response, these cells support tumor growth by increasing migration, invasion and proliferation of glioma cells. In the Laboratory of Molecular Neurobiology, granulocyte macrophage colony growth (GM-CSF) and osteopontin (SPP1) secreted by glioma cells were identified as crucial players in inducing the reprogramming of myeloid cells to the pro-tumor phenotype. The aim of the doctoral thesis was to identify synthetic peptides that block the interactions of GM-CSF or SPP1 with their respective receptors on myeloid cells. Peptide libraries that potentially bind GM-CSF or SPP1 were designed, and 78 peptides were synthesized. Binding specificity was determined with peptide arrays and enzyme-linked immunosorbent assay (ELISA). Ten peptides binding GM-CSF and 14 peptides binding SPP1 were identified, and their potential toxicity against BV2 mouse microglia and human U87 MG glioma cells was analyzed. Both murine BV2 and human SV40 microglial cells stimulated the invasion of various human glioma cells in matrigel matrix invasion assay. Based on the ability of peptides to inhibit glioma cell invasiveness, the two best-performing peptides were selected: G7 (for GM-CSF) and I49 (for SPP1). The G7 peptide binding to GM-CSFR receptor was verified using surface plasmon resonance and the Ligand Tracer apparatus, which assesses the interaction of GM-CSF with the receptor located on the cell surface. Treatment with G7 changed the transcriptional profile of glioma-activated microglia cells. The antitumor effect of the peptides, administered together with implanted glioma cells (single application) or using osmotic pumps (continuous delivery), was assessed in a mouse model of human glioma. The tumor size was measured by intravital tumor fluorescence measurement (with Xtreme imaging system) or using magnetic resonance imaging (MRI). Furthermore, silencing of SPP1 expression in U87 MG glioma cells reduced tumor growth in vivo and changed metabolite concentrations as assessed using H1MRS magnetic resonance spectroscopy. Both peptides are subjects to patent applications.}, title={Syntetyczne peptydy blokujące działanie GM-CSF lub osteopontyny w mikrośrodowisku nowotworu jako strategia terapeutyczna w leczeniu glejaków : praca doktorska}, type={Text}, keywords={Glioma, GM-CSF, Microglia, Osteopontin, Therapeutic peptides, Tumour microenvironment}, }