Increased Expression of T-Box Transcription Factor Protein 21 (TBX21) in Skin Cutaneous Melanoma Predicts Better Prognosis: A Study Based on The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) Databases

BACKGROUND: T-box transcription factor protein 21 (TBX21) is expressed in immune cells and some tumor cells. Defects in TBX21 gene can cause Th1/Th2 imbalance, which is closely related to tumorigenesis. The expression and clinical value of TBX21 in skin cutaneous melanoma (SKCM) are not clear. MATERIAL/METHODS: RNA-Seq expression and clinical information were downloaded from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases. Wilcoxon signed-rank test and logistic regression were used to explore the relationship between TBX21 expression and clinical parameters such as gender, stage, etc. The correlation between clinicopathological characteristics and overall survival of SKCM patients was estimated by Cox regression and the Kaplan-Meier method. Gene set enrichment analysis (GSEA) and protein-protein interaction (PPI) were conducted to analyze the potential mechanism of TBX21 in the progression of SKCM. RESULTS: Compared with normal samples, TBX21 was significantly upregulated in SKCM tissues. SKCM patients with lower TBX21 expression might have a worse prognosis than those with higher TBX21 expression according to Kaplan-Meier survival analysis. Cox analysis also reached the same conclusion: TBX21 was an independent prognostic indicator. GSEA showed that the highly expressed phenotypes in TBX21 were enriched to varying degrees with various signaling pathways. PPI network showed the top 10 proteins that were closely related to TBX21. CONCLUSIONS: TBX21 expression was significantly correlated with the prognosis of SKCM patients and was found to be involved in a great many immunological pathways that affect the occurrence and development of tumors.