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Tumor Discovery                                                   Bioinformatics insights into CCL2 mutations



            ensembl.org), which provides comprehensive genomic   proteins’ free energy indicates a change in stability, where
            information (Ensembl ID: ENSG00000108691).  This   negative  ΔΔG indicates destabilization, whereas positive
                                                    32
            dataset was chosen due to its extensive collection of   ΔΔG indicates stabilization. 27,42  Various computational
            genomic variations. In addition, data were obtained from   tools, including mCSM, SDM, and DUET, were employed
            the UniProtKB database (https://www.uniprot.org), which   to assess the impact of mutations on CCL2 protein stability
            includes sequence details in FASTA format (UniProt   and function, providing valuable insights into how specific
            ID: P13500), and the National Center for Biotechnology   mutations alter protein behavior. 27
            Information (NCBI) (https://www.ncbi.nlm.nih.gov). 33,34    The SDM online tool, available at http://marid.bioc.
            Structural information regarding CCL2 was retrieved from   cam.ac.uk/sdm2, accurately predicts the impact of
            the Protein Data Bank (PDB) (CCL2 PDB ID: 2LIE, and   mutations on protein stability through in silico analysis. It
            CCR2 PDB ID: 2LWL) through the website http://www.  examines variations in amino acid substitutions tolerated
            rcsb.org/. 35                                      by homologous proteins with known 3D structures in

            2.2. Computational prediction of mutation          specific environments, providing valuable insights into how
            pathogenicity                                      mutations can affect protein behavior and stability. 27,43,44
            To assess the effects of mutations on CCL2 proteins, we   The mCSM computational technique uses machine
            used computational methods essential for distinguishing   learning  to  predict  the  effects  of  missense  mutations  on
            between single-nucleotide variations that are detrimental,   CCL2 protein stability and function. It employs graph-based
            benign, or cancerous. Accurate evaluation of the functional   signatures to depict how mutations impact the interaction
            impacts of these genetic alterations is essential for   network among residues. By integrating evolutionary
            identifying disease-causing mutations. Meta-SNP (http://  information, complex network metrics, and energetic
            snps.biofold.org/meta-snp/) is a web-based tool that uses   factors, mCSM creates an accurate predictive model. It is
                                                                                                       21,26
            multiple predictive algorithms to assess the potential   available at http://structure.bioc.cam.ac.uk/mcsm.   The
            pathogenicity of protein mutations.  We employed meta-  mCSM method evaluates how mutations affect protein
                                        22
            SNP to assess mutation pathogenicity by integrating the   structure and interactions with other proteins and nucleic
            predictions from algorithms such as SNAP,  PhD-SNP,   acids. It provides insights into how mutations contribute
                                                36
            Panther,  and SIFT. 38                             to disease development, improving our understanding
                  37
                                                               of the molecular mechanisms of various diseases. This
              Meta-SNP is a reliable tool for predicting how mutations   computational approach clarifies the effects of mutations
            affect protein functions. It combines results from various   on protein stability, function, and interactions, enhancing
            algorithms using a random forest technique, which involves   our understanding of disease pathogenesis. 45,46
            100 decision trees within the WEKA library. This method   DUET (http://structure.bioc.cam.ac.uk/duet) is a
            ensures the precise assessment of a mutation’s impact on its
            protein function.  The meta-SNP algorithm was trained   computational tool that predicts changes in protein stability
                          39
            on the SV-2009 dataset through a 20-fold cross-validation   due to individual mutations. It combines two methods to
            procedure and provides dependable predictions of disease-  calculate the change in folding free energy (ΔΔG in Kcal/
                                                               mol), with negative  ΔΔG values indicating destabilizing
            causing variants.  It outputs a probability score between 0   mutations  and  positive  values  indicating  stabilizing
                         22
            and 1, with scores above 0.5 indicating a higher likelihood   mutations. 28,47  DUET uses support vector machines trained
            of the mutation being pathogenic. 40
                                                               with sequential minimal optimization to integrate the
              Next, we used the Polyphen-2 web server (http://  predictions from mCSM and SDM. This machine learning
            genetics.bwh.harvard.edu/pph2/), which is an automated   technique leverages the strengths of both methods to provide
            tool designed to predict the potential effects of amino   a  comprehensive  assessment  of how  missense  mutations
            acid substitutions on the structure and function of human   affect protein stability.  By  combining these predictive
            proteins.  This site features an input form that enables   capabilities, DUET enhances the accuracy and reliability of
                   41
            users to query either a single amino acid substitution or   mutation impact predictions on protein stability. 48
            a coding, non-synonymous SNP that is annotated in the
            dbSNP database. 23                                 2.4. Evaluating cancer-related mutations using the
                                                               FATHMM server
            2.3. Computational assessment of protein stability
                                                               The  FATHMM  server,  available  at  http://fathmm.
            Mutations can affect a protein’s structure and stability,   biocompute.org.uk, was used to assess the cancer relevance
            resulting in changes in free energy (ΔΔG in Kcal/mol). The   of deleterious mutations in CCL2. This web server predicts
            difference between the mutated (ΔGm) and original (ΔGw)   the functional consequences of both coding and noncoding


            Volume 3 Issue 4 (2024)                         4                                 doi: 10.36922/td.3891
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