Identification of potential serum biomarkers for breast cancer using a functional proteomics technology

Abstract

BackgroundCancer is a genetic disease; its development and metastasis depend on the function of many proteins. Human serum contains thousands of proteins; it is a window for the homeostasis of individual’s health. Many of the proteins found in the human serum could be potential biomarkers for cancer early detection and drug efficacy evaluation.MethodsIn this study, a functional proteomics technology was used to systematically monitor metabolic enzyme and protease activities from resolved serum proteins produced by a modified 2-D gel separation and subsequent Protein Elution Plate, a method collectively called PEP. All the experiments were repeated at least twice to ensure the validity of the findings.ResultsFor the first time, significant differences were found between breast cancer patient serum and normal serum in two families of enzymes known to be involved in cancer development and metastasis: metabolic enzymes and proteases. Multiple enzyme species were identified in the serum assayed directly or after enrichment. Both qualitative and quantitative differences in the metabolic enzyme and protease activity were detected between breast cancer patient and control group, providing excellent biomarker candidates for breast cancer diagnosis and drug development.ConclusionsThis study identified several potential functional protein biomarkers from breast cancer patient serum. It also demonstrated that the functional proteomics technology, PEP, can be applied to the analysis of any functional proteins in human serum which contains thousands of proteins. The study indicated that the functional domain of the human serum could be unlocked with the PEP technology, pointing to a novel alternative for the development of diagnosis biomarkers for breast cancer and other diseases.

Challenges and Opportunities in Clinical Applications of Blood-Based Proteomics in Cancer

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Recent Discoveries of Macromolecule- and Cell-Based Biomarkers and Therapeutic Implications in Breast Cancer

“…Cancer is a genetic disease, and its development and proliferation depend on the regulation of many proteins and miRNAs [ 179 ]. Human serum contains circulating proteins, miRNAs, and circRNAs, which could be potential therapeutic targets for breast cancer.…”

Identification of a Profile of Neutrophil-Derived Granule Proteins in the Surface of Gold Nanoparticles after Their Interaction with Human Breast Cancer Sera

“…Moreover, proteomics might identify protein biomarkers defining differences in prognosis, therapy resistance and metastatic spread within a specific subtype. Some proteins and peptides have been identified as breast cancer biomarkers in nipple aspirate fluid [11], breast tumor tissue [12], and serum [13]. Notably, serum biomarkers present the advantage that the sample is obtained through a minimally invasive method and can yield valuable information about the breast cancer status.…”