Exploring extracellular vesicle proteins as source of biomarkers for early detection of meningioma and predicting their therapeutic implications

BACKGROUND: Meningioma (MG) is a most common primary intracranial brain tumor. Patients survival and wellbeing can be increased by using immunological diagnostic assays, which are able to detect cases earlier and be used frequently. These techniques, in particular, depend on specific antibodies to identify the multitude of blood proteins known as biomarkers. Proteomic techniques are used to identify disease related Biomarkers in body fluids offering low-cost benefits and are less invasive. Cells release exosomes in both healthy and unhealthy circumstances. They are good source of biomarkers for clinical diagnostics because they transport proteins and nucleic acids from their host cells that are indicative of pathophysiological abnormalities. Exosomal proteins have the ability to control various aspects of tumor growth, such as metastasis, angiogenesis, the epithelial-mesenchymal transition, immunological modulation associated with tumors, and microenvironment reconstruction. Developing a drug to
promote or inhibit a certain chemical route or cycle in the body generally requires a thorough understanding of the pathways linked to disease. Drugs are made to target particular proteins inside the cellular network. Here, efforts have been made to show the application of exosomal proteome in meningioma detection using mass spectrometry and study drug development process by molecular docking simulations.
METHODS: Exosomes were isolated from 36 blood plasma samples which included 27 samples from MG grade 1 and 9 from healthy control samples. Isolated exosomes were characterized using techniques western blotting, NTA and flow cytometry. After characterization, samples were prepared for Mass-spectrometry (MS) and results were analyzed. For validation, ELISA of 3 selected proteins alongwith their in silico analyses was performed. Molecular Docking Simulations were also conducted for the target receptor (PI3K) and selected compounds.
RESULTS: Based on the literature search, fold change of exosomal proteins obtained from MS and in silico analyses, 3 proteins were selected. Validation for 3 proteins was
done by performing ELISA. When compared to healthy people, we found that meningioma (Gr I) patients' individual plasma specimens had considerably higher levels of Galectin-3BP, TGFBI, and POSTN. Further by using in silico approach to find FDA compounds as small inhibitors against PI3K/Akt pathway (common pathway of three proteins) using molecular docking simulations we obtained 4 drugs namely Cladribine > Fexofenadine > Dobutamine > Labeltalol.
CONCLUSION: Elevated levels of three exosomal proteins; Galectin-3BP, TGFBI and POSTN were identified and validated through MS analysis and ELISA respectively. These results alongwith in silico analysis proved these proteins as biomarkers of meningioma. Here, we have also found a few FDA-approved drugs through various computational techniques and checked their binding affinity with our target PI3K.