ABSTRACT
Nasopharyngeal carcinoma (NPC) is a highly metastatic and invasive malignant tumor that originates in the nasopharynx. The DNA-binding protein WD repeat and HMG-box DNA-binding protein 1 (WDHD1) are highly expressed in a variety of tumours, but its expression and mechanism of action in NPC have not been reported to date. To investigate the involvement of WDHD1 in NPC, we first mined databases for the gene expression profile of NPC. Immunohistochemistry (IHC) was performed on 338 cases of NPC and 112 non-NPC samples to verify the results. We report that the expression of WDHD1 is significantly elevated in NPC. ChIP-seq was used to show that integrin alpha V (ITGAV) and WDHD1 exhibit a significant binding peak in the promoter region of the ITGAV gene. The expression levels of ITGAV and WDHD1 exhibit a significant positive correlation, and IHC was performed to show that ITGAV is highly expressed in NPC. Expression of ITGAV increased after overexpression of WDHD1, suggesting that ITGAV may be a potential target gene of WDHD1. Pathway analysis showed that both genes were closely related to the cell cycle, and flow cytometry was used to further confirm that decreased expression of WDHD1 significantly increased the number of apoptotic cells. In conclusion, our results suggest that expression of WDHD1 is increased in NPC and is likely to be associated with the NPC cell cycle; thus, we propose that WDHD1 may have the potential as a target gene for primary screening and treatment of NPC.
Subject(s)
Integrin alphaV , Nasopharyngeal Neoplasms , Humans , Nasopharyngeal Carcinoma/genetics , Cell Line, Tumor , DNA-Binding Proteins , Nasopharyngeal Neoplasms/genetics , Nasopharyngeal Neoplasms/metabolism , Nasopharyngeal Neoplasms/pathologyABSTRACT
BACKGROUND: Currently, high expression of WD repeat and HMG-box DNA binding protein 1 (WDHD1) has been found in a variety of tumors; but there is no research has been conducted concerning the expression of WDHD1 in laryngeal squamous cell carcinoma (LSCC). Our purpose is to investigate the expression and the latent mechanism of WDHD1 in LSCC. METHODS: Firstly, 9 data sets from the Gene Expression Omnibus (GEO), The Cancer Genome Atlas (TCGA), and ArrayExpress were statistically analyzed to explore the expression of WDHD1 in LSCC; immunohistochemistry was performed in 79 LSCC tissues and 44 non-cancer tissues to further verify the result. In addition, the target gene of WDHD1 was predicted and immunohistochemistry was used to detect the expression of the target gene. The potential mechanism of WDHD1 in LSCC was investigated by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses and protein-protein interaction network (PPI). RESULTS: The WDHD1 mRNA was expressed at higher levels in the LSCC tissue than in the normal tissue (SMD=1.90, 95% CI=1.50-2.30); and the results of immunohistochemistry were consistent with the conclusion. Using chip-seq analysis, we found that S-phase kinase-associated protein 2 (Skp2) had a significant binding peak with WDHD1, and the expression of these two genes was significantly positively correlated. Immunohistochemistry showed that Skp2 was also highly expressed in LSCC. In addition, GO and KEGG analysis revealed the WDHD1 positively correlated genes was closely related to cell cycle, and PPI analysis identified 10 hub genes: COL7A1, COL4A2, COL4A1, COL4A6, COL11A1, COL5A2, COL1A1, COL13A1, COL8A1 and COL10A1, which may be critical to the progression of LSCC. CONCLUSIONS: WDHD1 was overexpressed in LSCC tissues. Meanwhile, WDHD1 and its target gene Skp2 for transcriptional regulation may play a role in the progression of LSCC by regulating the cell cycle.