Identification of gene markers associated with metastasis in clear cell renal cell carcinoma

The present study aimed to screen potential target genes for the early diagnosis and treatment of early metastatic clear cell renal cell carcinoma (ccRCC) using the microarray data of early metastatic and non-metastatic ccRCC samples. The DNA microarray dataset GSE47352 was downloaded from Gene Expression Omnibus and included 4 early metastatic and 5 non-metastatic ccRCC samples. Differentially expressed genes (DEGs) were screened using the limma package. Then, pheatmap package was used to conduct two-way clustering for the DEGs. Subsequently, MAPPFinder and GenMAPP were employed separately to perform functional and pathway enrichment analysis for the DEGs. Additionally, a protein-protein interaction (PPI) network was constructed using Cytoscape, and small drug molecules were searched using Connectivity map (cmap). In total, 196 upregulated and 163 downregulated genes were identified. DEGs, including JUN, tumor necrosis factor (TNF), Ras homolog family member B (RHOB) and transforming growth factor β2 (TGFβ2) were significantly enriched in the signaling pathway of renal cell carcinoma. Furthermore, nuclear receptor subfamily 4 group A member 1 (NR4A1) was significantly enriched in the mitogen-activated protein kinase signaling pathway; in addition, laminin subunit α (LAMA) 1, LAMA2 and LAMA4 were significantly enriched in extracellular matrix-receptor interaction. JUN (degree=6) had the highest degree in the PPI network. Thapsigargin (score=-0.913) possessed the highest performance in terms of the treatment of early metastatic ccRCC. In the present study, it was discovered that certain DEGs, including JUN, TNF, RHOB, NR4A1, TGFβ2, LAMA1, LAMA2 and LAMA4 were potential target genes associated with early metastatic ccRCC. In addition, thapsigargin could be used as an efficient small drug molecule for the treatment of early metastatic ccRCC.