Identification of the Role of Wnt/β-Catenin Pathway Through Integrated Analyses and in vivo Experiments in Vitiligo

Si-Jia Zhao; Hong Jia; Xiu-Lian Xu; Wen-Bo Bu; Qian Zhang; Xi Chen; Juan Ji; Jian-Fang Sun

doi:10.2147/CCID.S319061

Identification of the Role of Wnt/β-Catenin Pathway Through Integrated Analyses and in vivo Experiments in Vitiligo

Clin Cosmet Investig Dermatol. 2021 Sep 1:14:1089-1103. doi: 10.2147/CCID.S319061. eCollection 2021.

Authors

Si-Jia Zhao¹, Hong Jia², Xiu-Lian Xu¹, Wen-Bo Bu³, Qian Zhang³, Xi Chen⁴, Juan Ji², Jian-Fang Sun¹

Affiliations

¹ Department of Pathology, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, People's Republic of China.
² Department of Dermatology, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, People's Republic of China.
³ Department of Dermatologic Surgery, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, Jiangsu, People's Republic of China.
⁴ Department of Medicine 3, Universitätsklinikum Erlangen, Friedrich Alexander University Erlangen Nuremberg, Erlangen, Bavaria, Germany.

Abstract

Purpose: Vitiligo is an acquired depigmentation skin disease, which affects an average of 1% of the world's population. The purpose of this study is to identify the key genes and pathways responsible for vitiligo and find new therapeutic targets.

Methods: The datasets GSE65127, GSE53146, and GSE75819 were downloaded from the Gene Expression Omnibus (GEO) database. R language was used to identify the differentially expressed genes (DEGs) between lesional skin of vitiligo and non-lesional skin. Next, the key pathways were obtained by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. The protein-protein interaction (PPI) networks were conducted by STRING database and Cytoscape software. Subsequently, module analysis was performed by Cytoscape. Among these results, the Wnt/β-catenin pathway and melanogenesis pathway caught our attention. The expression level of β-catenin, microphthalmia-associated transcription factor (MITF) and tyrosinase (TYR) was detected by immunofluorescence in vitiligo lesions and healthy skin. Moreover, zebrafish was treated with XAV-939, an inhibitor of the Wnt/β-catenin pathway. After that, the area of melanin granules as a percentage of the head area was measured. The mRNA expression of β-catenin, lymphoid-enhancing factor 1(lef1), tyr and mitf were detected by q-PCR (quantitative polymerase chain reaction) in zebrafish (Danio rerio).

Results: A total of 2442 DEGs were identified, including 1068 upregulated and 1374 downregulated DEGs. The key pathways were identified by GO and KEGG analyses, such as "NOD-like receptor signaling pathway", "Wnt signaling pathway", "Melanogenesis", "mTOR signaling pathway", "PI3K-Akt signaling pathway", "Calcium signaling pathway" and "Rap1 signaling pathway". The immunofluorescence results showed that the level of β-catenin, MITF and TYR was significantly downregulated in vitiligo lesional skin. In zebrafish, the mean percentage area of melanin granules and the expression of β-catenin, lef1, tyr and mitf were decreased after treated with XAV-939.

Conclusion: The present study identified key genes and signaling pathways associated with the pathophysiology of vitiligo. Among them, the Wnt/β-catenin pathway played an essential role in pigmentation and could be a breakthrough point in vitiligo treatment.

Keywords: Rap1; Wnt/β-catenin; calcium signaling; melanogenesis; vitiligo; zebrafish.