Purchase this article with an account.
Ksenia Keller, Julia Pieter, Daniel Boehm, Nils Boehm, Dominik Wolters, Heinz Koelbl, Norbert Pfeiffer, Franz Grus; Proteomic Analysis Of Tear Fluid Of Breast Cancer Patients And Healthy Subjects Shows Differences In Protein Expression Levels. Invest. Ophthalmol. Vis. Sci. 2011;52(14):3724. doi: https://doi.org/.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Breast cancer is one of the leading death causes in women worldwide. The crucial requirement of its curability is the early detection. Currently, there are no molecular biomarkers available for this purpose. Proteomic analysis of tear fluid has a great potential and benefit due to non-invasive sample retrieval and low required protein amounts. In previous studies we found several alterations in tear protein levels which could discriminate cancer patients from the controls. Here we performed a new proteomic study with tear proteins from both groups.
Tear fluid was obtained from 25 patients with primary diagnosed breast carcinoma and 25 age-matched healthy women with the help of Schirmer test. Tear proteins were eluted overnight with 0.1% n-dodecyl-beta-D-maltoside. Then the individual samples were pooled according to cancer (CA) or healthy (CTRL) group and separated due to molecular weight of proteins via electrophoresis. After following digestion procedure the proteins were identified via Matrix-assisted Laser Desorption/Ionization Mass Spectrometry (MALDI-TOF/TOF MS). Finally, after normalization and evaluation steps, a semi-quantitative comparison of protein expression levels was performed.
In our study more than 150 proteins were identified through MALDI-TOF/TOF MS. These proteins include several major components of tear fluid like lipocalin-1 (LCN1), lactotransferrin (TRFL) or lysozyme c (LYSC). Besides different expression of high abundant proteins we found at least 10 proteins in CA and CTRL involved for instance in metabolic regulation (e. g. oxidoreductases like aldehyde dehydrogenase AL3A1), that were distinctly up- or down-regulated by at least two-fold.
In our study we could show a promising possibility for protein profiling of tear proteins of breast cancer patients and healthy group. Furthermore, we detected several alterations in expression levels of proteins in both cohorts. Additional analyses and validation of these differently expressed putative biomarkers can facilitate the understanding of breast cancer emergence and development and maintain the search for the new protein biomarkers of this disease.
This PDF is available to Subscribers Only