Interferon-Inducible Protein 16 (IFI16) is a Prognostic Biomarker and Related to Immune Infiltrates in Renal Cell Carcinoma (RCC)

Abstract

Background: Renal cell carcinoma is one of the most common and lethal types of cancer within the urinary system. the current challenges include how to diagnose RCC in the earlier stage and the drug resistance to chemotherapy or radiotherapy. Therefore, to investigate the survival rate and immune infiltration in RCC base on gene expression of IFI16 in RCC. Methods: We explored the relationship between the transcription level of IFI16 and clinical data in RCC through various online databases, including ONCOMINE, GEPIA, Timer and COEXPEDIA. Results: In comparison with the corresponding normal tissues, the mRNA expression levels of IFI16 are higher in KIRC tissues (p＜ 0.05), while lower in KICH tissues (p＜0.05). The mRNA expression of IFI16 has a positive correlation with TNM stage in KIRC(p=8.56e-07) and KIRP(p=0.00078). In KIRC, the higher expression of IFI16 suggests lower OS（HR=1.4; P=0.037; Log-rank p=0.037). In KIRP, the higher expression of IFI16 suggests lower DFS and OS (respectively, HR=1.9, P=0.037, Log-rank p=0.034; HR=2.3, P=0.011, Log-rank p=0.0091). In contrast, the expression level of IFI16 has a negative correlation with the tumour purity in KICH, KIRC and KIRP via the Timer database (all, p < 0.05). In KIRC and KIRP, the expression level of IFI16 has a positive correlation with the tumor-infiltrating immune cells (TIICs) (all, p < 0.05), except the macrophages in KIRP. In KIRC, the main TIICs in the arm-level deletion state of the IFI16 gene were B cell, CD4+T cell, Neutrophil, and Dendritic cell, while the main TIICs in the high amplification state were Macrophage (all, p < 0.0001). 108 genes are co-expressed with the IFI16 gene. Function enrichment analysis by GO and KEGG mainly enriched on some functions, including neutrophil degranulation, phagocytosis, vesicle-mediated transport regulation and enriched on some signal pathways, including tuberculosis, toxoplasmosis, phagosome, leishmaniasis, and Fc gamma R-med8ted. Conclusions: IFI16 acts as an oncogene in the progression of kidney cancer which is overexpressed in the RCC tissues. Apart from that, IFI16 has been determined as a marker of diagnosis and prognosis in RCC, which might be associated with the immune infiltration.