Identification of C4BPA as biomarker associated with immune infiltration and prognosis in breast cancer

Background: C4BPA is a gene that encodes the C4BP protein α chain and is involved in the complement system. C4BPA is regarded as a new biomarker for cancer, especially for non-small cell lung cancer and ovarian cancer. However, its role in breast cancer (BC) has not yet been determined.

Methods: In this research, we used a bioinformatics approach to assess the prognostic significance of C4BPA in BC. Utilizing a variety of databases and analysis tools, including The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), R, STRING, and the Kaplan-Meier plotter, we specifically assessed the connection between C4BPA and BC.

Results: C4BPA expression was markedly decreased in BC tissues compared to its expression in normal breast tissues (P<0.05). Additionally, a receiver operating characteristic (ROC) curve revealed that C4BPA has a significant capacity for prognostication and diagnostics. Additionally, C4BPA expression was linked to some immune infiltrating cells' functionality, according to gene set enrichment analysis (GSEA) and immune infiltration analysis. Low C4BPA expression was additionally related to poor progression-free interval (PFI) and overall survival (OS), according to the Kaplan-Meier method. We also found that C4BPA expression was independently connected to PFI and OS through Cox regression analysis. Finally, prognostic analysis of the various subgroups of breast invasive carcinoma (BRCA/BIC) in TCGA showed that patients with low C4BPA expression might have worse PFI and OS in patients with Luminal A compared to other BC subtypes.

Conclusions: In conclusion, these results revealed that C4BPA could potentially act as a diagnostic biomarker for BC patients indicating unfavorable prognoses and offers valuable knowledge for creating therapeutics and prognostic indicators.