Background: Lung adenocarcinoma (LUAD) is one of the tumor-related diseases with high morbidity worldwide. Epigenetic modifications such as DNA methylation changes may involve in tumorigenesis. This study aimed to explore new biomarkers that have prognostic significance of LUAD.
Methods: First, we downloaded the gene expression and methylation data set from Gene Expression Omnibus. R software was then used to identify abnormally methylated differentially expressed genes (MDEGs). Next, R package Cluster Profiler was used to analyze the enrichment and pathway of the MDEGs. Analysis using STRING revealed the protein-protein interaction network. The result was then visualized by Cytoscape and obtained 10 hub genes. Afterward, they were further verified by The Cancer Genome Atlas to select candidate genes. Moreover, quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry were used to verify the expression and prognostic value of candidate genes in LUAD patients.
Results: The results showed that the expressions of ADCY5 and PRKCB are indeed related to LUAD. The clinical relevance to PRKCB was confirmed by its clinical correlation analysis. Gene set enrichment analysis (GSEA) and tumor immune estimation resource (TIMER) tumor immune correlations showed that PRKCB is involved in the cancer-related Kyoto Encyclopedia of Genes and Genomes pathway and is involved in immune infiltration. It was also verified by qRT-PCR and immunohistochemistry that PRKCB was lowly expressed in LUAD patients and correlated with prognosis.
Conclusions: PRKCB is relevant to prognosis of LUAD through methylation and immune infiltration.
Keywords: DNA methylation; LUAD; bioinformatics analysis; immune infiltration; survival analysis.
© 2022 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.