Breast cancer biomarkers identified in the Gene Expression Omnibus and The Cancer Genome Atlas

Breast cancer (BC) is one of the most malignant tumors in women and a serious threat to women’s health. The incidence of BC has been increasing in China, and the age of onset is earlier compared with that in Western countries. BC remains a major cause of cancer mortality and morbidity in women, as this cancer does not respond well to conventional therapies. Diagnosis is difficult because of non-specific manifestations and the poor accuracy of conventional tests. There is also uncertainty about the optimal screening modality and target populations, as well as the specifications and implementation of screening programs. It is thus imperative to identify diagnostic and prognostic biomarkers for BC. Overlapping differentially expressed genes were screened based on Gene Expression Omnibus (GSE36765, GSE10810, and GSE 20086) and The Cancer Genome Atlas datasets. A protein-protein interaction network was applied to excavate the hub genes among these differentially expressed genes. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses, as well as gene set enrichment analyses, were conducted to examine the functions of these genes and their potential mechanisms in the development of BC. For clarification of the diagnostic and prognostic roles of these genes, Kaplan–Meier and Cox proportional hazards analyses were conducted. In conclusion, this study demonstrated that CALR, HSPB1, IGF1, IL1R1, KLF4, SOCS3, and TPI1 are potential diagnostic biomarkers of BC as well as potential treatment targets with clinical implications.