NIFK, a Potential Prognostic and Immunological Biomarker in Pan-- Cancer Analysis, Significantly Regulates Proliferation and Metastasis of Colorectal Cancer.

BACKGROUND As a binding protein of Ki67, NIFK plays an important role in the mitosis of cells and is closely related to the progression of specific types of tumors. However, there is still a lack of systematic analysis of NIFK in pan-cancer and insufficient research to explore its role in human tumors. METHODS We systematically evaluated the pan-cancer expression and mutation of NIFK in human cancers using data from The Cancer Genome Atlas (TCGA) through large-scale bioinformatics analysis. In addition, we explored the pan-cancer immunological characteristics of NIFK, especially in colorectal adenocarcinoma (COAD). Furthermore, we used single-cell sequencing to analyze the expression of NIFK in different cells of COAD tissues and performed GO, KEGG, and gene set enrichment analysis of NIFK in COAD. Lastly, we evaluated the effects of NIFK knockdown on the colorectal cancer cell lines in in vitro experiment. RESULTS We found that NIFK was overexpressed in almost all types of tumors and showed significant prognostic efficacy. Additionally, correlations between NIFK and specific immune features, such as immune cell infiltration, immune checkpoint genes, TMB, and MSI, suggest that NIFK may be used to guide immunotherapy. Subsequently, it was found that the expression of NIFK was significantly upregulated in tumor cells through single-cell sequencing analysis, and the NIFK gene was closely associated with tumor progression and immune therapy response. Finally, we further elucidated the role of NIFK in colorectal cancer and found that downregulation of NIFK expression could inhibit the proliferation, migration, and invasion ability of colorectal cancer cells. CONCLUSION The results of this study demonstrated that NIFK, as a member of the pan-cancer genes, will serve as a biomarker and a potential therapeutic target for a range of cancer types, providing new insight into precision medicine.