AUTHOR=Zhang Yao-Hua , Zeng Jing , Liu Xu-Sheng , Gao Yan , Kui Xue-Yan , Liu Xiao-Yu , Zhang Yu , Pei Zhi-Jun TITLE=ECE2 is a prognostic biomarker associated with m6A modification and involved in immune infiltration of lung adenocarcinoma JOURNAL=Frontiers in Endocrinology VOLUME=Volume 13 - 2022 YEAR=2022 URL=https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2022.1013238 DOI=10.3389/fendo.2022.1013238 ISSN=1664-2392 ABSTRACT=Abstract Background: The targeted therapy for lung cancer relies on prognostic genes and requires further research. No research has been conducted to determine the effect of endothelin-converting enzyme 2 (ECE2) in lung cancer. Methods: We analyzed the expression and clinicopathological characteristics of ECE2 in lung adenocarcinoma (LUAD) tissues and normal adjacent tissues from the tumor Genome Atlas (TCGA) and Gene Expression Comprehensive Database (GEO). Immunohistochemical staining was used for further verification of the findings. In a logistic regression model, a correlation was determined between ECE2 expression and clinicopathological features. Cox regression analysis and Kaplan-Meier analysis were used to determine the predictive value of ECE2 for clinical outcomes in LUAD patients. GO/KEGG enrichment analysis and gene set enrichment analysis (GSEA) were performed using R software for co-expression of ECE2. Data from TIMER, GEPIA database, and TCGA were analyzed to determine the relationship between ECE2 expression and LUAD immune infiltration. To investigate the relationship between ECE2 expression level and LUAD m6A modification, TCGA data and GEO data were analyzed. Results: Based on ROC curves, ECE2 can predict the prognosis of tumors and normal samples with significant accuracy in a variety of tumors. ECE2 expression in LUAD is closely related to tumor stage. ECE2 is closely related to mitochondrial gene expression, ATPase activity, and cell cycle according to GO/KEGG enrichment analysis. The enrichment pathways of ECE2-related differential genes are predominantly associated with the cell cycle, MYC signaling pathway, WNT signaling pathway, DNA methylation pathway, and transcription. Results from TIMER, The expression of ECE2 is inversely linked with B cells, CD4 cells, and dendritic cells in the GEPIA database and the TCGA data set. In TCGA and GEO data sets, significant correlations were found between ECE2 expression and HNRNPC, IGF2BP1, IGF2BP3, and RBM15. Conclusion: It is associated with methylation and is a prognostic biomarker of LUAD immune infiltration.