| Abstract: | Background: Cytochrome b561 (CYB561) plays a critical role in neuroendocrine function, cardiovascular regulation, and tumor growth; however, the prognostic value of CYB561 in patients with breast cancer and the relationship between CYB561 expression and immune infiltration in breast cancer remain unclear. Methods: The mRNA expression and clinical data of patients with breast cancer were obtained from The Cancer Genome Atlas database. Functional enrichment analysis was used to explore underlying biological functions associated with CYB561. The methylation status of CYB561 was analyzed using the MethSurv database. The enrichment score of immune cell infiltration for CYB561 in breast cancer was calculated using single-sample gene set enrichment analysis. The prognostic value of CYB561 was evaluated using Kaplan-Meier method and Cox regression analysis. Based on the results of the multivariate Cox analysis, a nomogram was constructed to predict the effect of CYB561 expression on overall survival (OS). Results: The results showed that CYB561 was highly expressed in breast cancer tissues. Hypomethylation of CYB561 is associated with an unfavorable prognosis. In multivariate Cox regression analysis, CYB561 was an independent prognostic factor for OS. Functional enrichment analysis indicated that estrogen signaling pathway, inflammatory response, KRAS signaling pathway, epithelial-mesenchymal transition, leukocyte migration, and regulation of lymphocyte activation were strongly enriched in the low CYB561 expression group. Additionally, CYB561 expression was negatively correlated with immune infiltration of B cells, plasmacytoid dendritic cells, dendritic cells, and neutrophils. Conclusion: CYB561 may serve as a potential biomarker for breast cancer diagnosis and prognosis. |
