Abstract

Breast cancer is the most frequent type of cancer in women. For treatment decisions, accurate prognosis of breast cancer and its clinical stages is critical. Although several researches have been conducted to identify circulating biomarkers of breast cancer, no such biomarkers for distinct stages of the illness have been reported. We identified blood protein biomarkers for each stage of breast cancer in this work by examining patient transcriptome and proteome data. A high number of genes were found to be differently expressed in tumor samples from each stage of breast cancer when compared to surrounding normal tissues in the TCGA transcriptome datasets. Bioinformatics tools were then used to anticipate blood-secretory proteins encoded by these genes. Furthermore, plasma samples from breast cancer patients at various stages were subjected to iTRAQ-based proteome analysis. A fraction of the expected blood-secretory proteins were found to be differently expressed. Finally, due to their consistent expression patterns at both the mRNA and protein levels, numerous proteins were chosen as potential blood protein biomarkers for distinct stages of breast cancer. Overall, our findings add to our understanding of breast cancer diagnosis and classification, as well as treatment selection.