Abstract
BACKGROUND: Echinoderm microtubule-associated protein-like 2 (EML2), a gene located on 19q13.32, is overexpressed in various cancers and has been identified as a prognostic factor. However, the function and carcinogenic mechanism of EML2 in colon cancer is yet to be explored. METHODS: This study aimed to demonstrate the relationship between EML2 expression and colon cancer using The Cancer Genome Atlas (TCGA) database. The EML2 expression, including GSE33113 and GSE39923, was validated in colon cancer in the Gene Expression Omnibus (GEO) database. The Receiver Operating Characteristic (ROC) curves were used to assess the feasibility of EML2 as a distinguishing factor from the area under the curve (AUC) scores. In addition, Cox regression and logistic regression analyses were conducted to evaluate the factors linked to the prognosis of colon cancer. Moreover, the STRING tool was used to establish the EML2 binding protein network. The enrichment analysis cluster Profiler of the R package was utilized to investigate the function of EML2. The relationship between the immune infiltration and EML2 expression level in colon cancer was investigated by the R package Gene Set Variation Analysis (GSVA) and the single sample Gene Set Enrichment Analysis (ssGSEA) method in the Tumor Immune Estimation Resource (TIMER) database. RESULTS: Pan-cancer data analysis revealed that EML2 expression was higher in most cancers, including colon cancer. This outcome was in line with the findings of the GEO database. The ROC curve demonstrated that EML2 can serve as a diagnostic biomarker for colon cancer (AUC = 0.738). High EML2 expression was associated with poorer overall survival (OS; P = 0.004). Moreover, the results of the enrichment and immune infiltration analysis revealed that high EML2 expression correlated with regulation of the infiltration level of GTPase binding and some immune cell types like NK cells and NK CD56 bright cells. CONCLUSION: The findings revealed that colon cancer tissues had a higher EML2 expression than normal colon epithelial tissues. This phenomenon was significantly associated with poor prognosis and altered immune cell infiltration. Consequently, EML2 has shown the capacity to serve as a prognostic biomarker for patients diagnosed with colon cancer.