Lung cancer is the second most common cancer in the world. The aim of this study is to identify biomarkers for lung cancer that can aid in its diagnosis and treatment. The gene expression profiles from GEO database were analyzed by GEO2R to identify Differentially Expressed Genes (DEGs) and further analyzed using Cytoscape. The data was divided into two categories: non-treatment and treatment groups. A total of 407 DEGs (254 upregulated and 153 downregulated) and 259 DEGs (124 upregulated and 135 downregulated) were isolated for non-treatment and treatment studies respectively. The significant Gene Ontologies and pathways enriched with DEGS were identified using Cytoscape apps, BiNGO and ReactomeFIPlugIn, respectively. Hub genes based on network parameters - Degree, Closeness and Betweenness - were isolated using CytoHubba. In conclusion, DEGs identified in this study may play an important role in early diagnosis or as biomarkers of lung cancer.
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Five Critical Gene-Based Biomarkers With Optimal Performance for Hepatocellular Carcinoma
Hepatocellular carcinoma (HCC) is one of the most fatal cancers in the world. There is an urgent need to understand the molecular background of HCC to facilitate the identification of biomarkers and discover effective therapeutic targets. Published transcriptomic studies have reported a large number of genes that are individually significant for HCC. However, reliable biomarkers remain to be determined. In this study, built on max-linear competing risk factor models, we developed a machine learning analytical framework to analyze transcriptomic data to identify the most miniature set of differentially expressed genes (DEGs). By analyzing 9 public whole-transcriptome datasets (containing 1184 HCC samples and 672 nontumor controls), we identified 5 critical differentially expressed genes (DEGs) (ie, CCDC107, CXCL12, GIGYF1, GMNN, and IFFO1) between HCC and control samples. The classifiers built on these 5 DEGs reached nearly perfect performance in identification of HCC. The performance of the 5 DEGs was further validated in a US Caucasian cohort that we collected (containing 17 HCC with paired nontumor tissue). The conceptual advance of our work lies in modeling gene-gene interactions and correcting batch effect in the analytic framework. The classifiers built on the 5 DEGs demonstrated clear signature patterns for HCC. The results are interpretable, robust, and reproducible across diverse cohorts/populations with various disease etiologies, indicating the 5 DEGs are intrinsic variables that can describe the overall features of HCC at the genomic level. The analytical framework applied in this study may pave a new way for improving transcriptome profiling analysis of human cancers.
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- Award ID(s):
- 2012298
- PAR ID:
- 10470588
- Publisher / Repository:
- Sage
- Date Published:
- Journal Name:
- Cancer Informatics
- Volume:
- 22
- ISSN:
- 1176-9351
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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