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Eurasian Journal of
            Medicine and Oncology                                                   Prognosis of colon adenocarcinoma



            pathological form of colon cancer is colon adenocarcinoma   were  developed  using  weighted  gene  co-expression
            (COAD).  Oncogene activation and inactivation are two   network analysis, and network topology was analyzed with
                   2
            examples of the multistage, multigene processes involved   a soft-threshold power ranging from 1 to 30. The relational
            in the formation of COAD.  Treatment of tumors requires   matrix was then converted into the adjacent matrix and
                                 2,3
            early detection and timely aggressive excision. Patients   transformed into a topological overlap matrix for average
            with colorectal cancer have a 5-year survival rate of   link hierarchy clustering to classify related modules.
            almost 90% if they receive an early diagnosis, compared   The correlation between modules and clinical traits was
            to only 12% for those who have distant metastases.  A   assessed using Pearson methods.
                                                       4
            2020 study on colorectal cancer incidence revealed a
            declining trend in highly developed nations, possibly   2.3. Modeling-associated genes identification and
                                         1,5
            due to improved disease screening.  Identifying suitable   prognostic signature construction
            biomarkers is crucial for risk assessment, early diagnosis,   The LASSO regression analysis was performed on the
            and treatment outcome prediction. Risk stratification in   survival-related genes to avoid the collinearity of high-
            COAD can be enhanced using gene expression profiles.    dimensional transcriptome data to identify modeling genes.
                                                          6
            However, many studies have not thoroughly examined   The value of this mRNA signature for the prognosis of
            the genes associated with the clinical prognosis of COAD   colorectal patients was verified using the Kaplan–Meier (KM)
            patients. Prognostic biomarkers can significantly influence   curve and log-rank test. The modeling data set’s core genes
            the risk classification of COAD patients,  with high-  were identified using univariate Cox regression analysis with
                                               7
            risk groups benefiting from more intensive treatment   p<0.05 as the threshold. Multi-factor Cox regression analysis
            to prevent undertreatment. In contrast, low-risk groups   was used to analyze the risk score, which was then used to
            should receive low-intensity treatment regimens to avoid   classify patients into high- and low-risk groups.
            overtreatment. Hence, to assess the clinical prognosis of
            COAD patients, we evaluated gene modules and identified   2.4. Predictive accuracy of the risk signature
            potential biomarkers.                              The eight-mRNA signature’s predictive significance was
              The relationship between COAD and the genome was   evaluated through internal and external validation.
            evaluated using weighted gene co-expression network   2.5. Protein expression levels and genetic
            analysis.  Furthermore, the least absolute shrinkage and   alterations of prognostic genes validation
                  8
            selection operator (LASSO) Cox regression and univariate
            proportional hazards analyses were used to identify an   The cBioPortal database (https://www.cbioportal.org/)
            mRNA signature closely linked to the prognosis of COAD,   was used to investigate the mutation status of key genes
            surpassing clinical criteria. Ultimately, the gene signature   in the mRNA signature, whereas the Human Protein Atlas
                                                                      11
            and clinical characteristics were combined to create a   database  (https://www.proteinatlas.org/) was utilized to
            nomogram to predict prognosis.                     verify the protein expression levels of these genes through
                                                               immunohistochemistry.
            2. Materials and methods
                                                               2.6. Immune landscape differences of colon
            2.1. Data retrieval process                        adenocarcinoma patients across risk strata
            All bioinformatics and statistical analyses were performed   The single-sample gene set enrichment analysis (ssGSEA)
            using R software (version 4.2.0). Raw data were obtained   algorithm was employed to ascertain the impact of
            from the Cancer Genome Atlas Program (TCGA) (https://  high- and low-risk groups on immune cell infiltration and
            portal.gdc.cancer.gov/), which included 647 colorectal   immune function in the TCGA and GEO cohorts.
            cancer  patients  with  complete  survival  information.
            From the Gene Expression Omnibus (GEO) (http://www.  2.7. Univariate and multi-factor Cox regression
            ncbi.nlm.nih.gov/geo/) database, the GSE39582 dataset    analysis
                                                          9
            was used for validation.  The TCGA dataset contained   Cox regression analyses, both univariate and multivariate,
                                10
            647 tumor samples and 51 normal samples, whereas the   were conducted on age, sex, stage, TNM staging, and
            GSE39582 dataset included 556 colorectal cancer samples.  other  clinical factors  in the  TCGA  and GEO  cohorts.
                                                               This analysis was conducted to confirm the mRNA risk
            2.2. Co-expression network construction
                                                               signature’s  independent predictive  value.  Univariate
            In this study, intramodular hub genes were selected   and multivariate Cox regression, KM curves, and log-
            using the criterion of gene significance>0.2  and module   rank tests were performed using the R package survival
            membership>0.8. Weighted gene co-expression networks   (version 3.3 1) and “survminer” (version 0.4.9).


            Volume 9 Issue 2 (2025)                        235                         doi: 10.36922/EJMO025060024
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