Comparative two‐dimensional polyacrylamide gel electrophoresis (2D‐PAGE) of human milk to identify dysregulated proteins in breast cancer

Abstract

Breast cancer (BC) remains a major cause of mortality, and early detection is considered important for reducing BC-associated deaths. Early detection of BC is challenging in young women, due to the limitations of mammography on the dense breast tissue of young women. We recently reported results of a pilot proteomics study, using one-dimensional polyacrylamide gel electrophoresis (1D-PAGE) and mass spectrometry (MS) to investigate differences in milk proteins from women with and without BC. Here, we applied two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and MS to compare the protein pattern in milk from the breasts of a single woman who was diagnosed with BC in one breast 24 months after donating her milk. Statistically different gel spots were picked for protein digestion followed by nanoliquid chromatography tandem MS (nanoLC-MS/MS) analysis. The upregulated proteins in BC versus control are alpha-amylase, gelsolin isoform a precursor, alpha-2-glycoprotein 1 zinc isoform CRA_b partial, apoptosis-inducing factor 2 and vitronectin. Several proteins were downregulated in the milk of the breast later diagnosed with cancer as compared to the milk from the healthy breast, including different isoforms of albumin, cholesterol esterase, different isoforms of lactoferrin, different proteins from the casein family and different isoforms of lysozyme. Results warrant further studies to determine the usefulness of these milk proteins for assessing risk and detecting occult disease. MS data is available via ProteomeXchange with identifier PXD009860.

Understanding seasonal weight loss tolerance in dairy goats: a transcriptomics approach

“…On the contrary, NR4A1 and LOC102168230, which code for nuclear receptor subfamily 4 group A member 1 and alpha-2-glycoprotein 1, zinc-binding, respectively had higher expression in the PE group. The first protein is associated to oxidative stress and induced apoptosis in human fibroblasts [78], whereas the latter is related to apoptosis in human breast cancer [79]. The up-regulation of these two genes in the PE group is therefore likely related to a more exacerbated involution-induced apoptosis in these animals.…”

2D SDS PAGE in Combination with Western Blotting and Mass Spectrometry Is a Robust Method for Protein Analysis with Many Applications

“…Aslebagh et al used 2D SDS PAGE in combination with MS to determine if milk proteins were affected by breast cancer [18]. Silver-stained 2D SDS PAGE patterns of milk from a woman diagnosed with breast cancer were compared to those of normal milk from the other breast for differences.…”

“…Five upregulated and five downregulated proteins in breast cancer versus control were identified. These potential biomarkers may provide a way to predict breast cancer aggressiveness [18].…”

Identification of dysregulation of atrial proteins in rats with chronic obstructive apnea using two‐dimensional polyacrylamide gel electrophoresis and mass spectrometry

“…The rats and the rat model setup ( Figure S1) and the sample preparation method used in this study was described previously. 3,6 Atrial homogenates of control (n = 2), moderate (n = 2) and severe (n = 2) apnea were analysed by 2D PAGE and nanoLC-MS/MS analysis. A total of 2293 protein spots were compared for statistical differences, of which 208 spots having a fold increase or decrease of ≥1.7 and a P ≤ 0.05, or a fold increase or decrease of ≥3.0 were selected for nanoLC-MS/MS analysis, as previously described.…”