Infrared Microspectroscopy and Imaging Analysis of Inflammatory and Non-Inflammatory Breast Cancer Cells and Their GAG Secretome.

Hossam Taha Mohamed,Ganesh D Sockalingum,Martin Götte,Gianfelice Cinque,Sherif Abdelaziz Ibrahim,Nguyet Que Nguyen,Romain Rivet,Valérie Untereiner,Stéphane Brézillon

doi:10.3390/molecules25184300

Abstract

Glycosaminoglycans (GAGs)/proteoglycans (PGs) play a pivotal role in the metastasis of inflammatory breast cancer (IBC). They represent biomarkers and targets in diagnosis and treatment of different cancers including breast cancer. Thus, GAGs/PGs could represent potential prognostic/diagnostic biomarkers for IBC. In the present study, non-IBC MDA-MB-231, MCF7, SKBR3 cells and IBC SUM149 cells, as well as their GAG secretome were analyzed. The latter was measured in toto as dried drops with high-throughput (HT) Fourier Transform InfraRed (FTIR) spectroscopy and imaging. FTIR imaging was also employed to investigate single whole breast cancer cells while synchrotron-FTIR microspectroscopy was used to specifically target their cytoplasms. Data were analyzed by hierarchical cluster analysis and principal components analysis. Results obtained from HT-FTIR analysis of GAG drops showed that the inter-group variability enabled us to delineate between cell types in the GAG absorption range 1350–800 cm−1. Similar results were obtained for FTIR imaging of GAG extracts and fixed single whole cells. Synchrotron-FTIR data from cytoplasms allowed discrimination between non-IBC and IBC. Thus, by using GAG specific region, not only different breast cancer cell lines could be differentiated, but also non-IBC from IBC cells. This could be a potential diagnostic spectral marker for IBC detection useful for patient management.

Highlights

Glycosaminoglycans (GAGs) are unbranched and negatively charged heteropolysaccharides consisting of repeating disaccharide units of alternating uronic acids and N-acetylated hexosamine [1].Molecules 2020, 25, 4300; doi:10.3390/molecules25184300 www.mdpi.com/journal/moleculesThe majority of GAGs are covalently attached to core proteins to form proteoglycans (PGs) [2]
Vibrational spectroscopy can be such a tool. It is an analytical approach used in the diagnosis of many diseases including cancer as it has the ability to detect subtle biochemical changes prior to any morphological changes, which translates into a modification of the spectral profile [30]. These modifications are related to alterations in the concentration and the conformation of functional groups associated with cell components such as nucleic acids, proteins, lipids, carbohydrates or macromolecules present in the extracellular matrix such as collagen, elastin, PGs, small leucine-rich proteoglycans (SLRPs), and GAGs
In order to assess the total amount of sulfated GAGs synthesized by each breast cancer cell type, a BlyscanTM assay was performed on the respective extracted GAGs

Summary

Introduction

The majority of GAGs are covalently attached to core proteins to form proteoglycans (PGs) [2]. PGs are involved in several biological functions, where they modulate cell growth-factor activation, regulate collagen fibrillogenesis, affect tumor cell growth and invasion, and influence corneal transparency [3]. GAGs and PGs represent one of the major macromolecules of the ECM [1] and play important roles in cancer progression, where changes in their expression and enzymes involved in their biosynthesis and/or degradation occur [1]. Chondroitin sulfate proteoglycans (CSPGs) were shown to activate the extracellular signal-regulated kinase and focal adhesion kinase in melanoma [4]. A major dermatan sulfate proteoglycan (DSPG), was demonstrated to regulate epidermal growth factor receptor (EGFR) signaling, controlling proliferation in melanoma [5]

Methods

Discussion

Conclusion