Synchrotron Fourier-Transform Infrared Microspectroscopy: Characterization of in vitro polarized tumor-associated macrophages stimulated by the secretome of inflammatory and non-inflammatory breast cancer cells

• Published in: Biochimica et biophysica acta. Molecular cell research 2023-01, Vol.1870 (1), p.119367-119367, Article 119367
• Main Authors: Mohamed, Hossam Taha, Kamel, Gihan, El-Husseiny, Noura, El-Sharkawy, Aya Ali, El-Sherif, Ahmed A., El-Shinawi, Mohamed, Mohamed, Mona Mostafa
• Format: Article
• Language: English
• Subjects: Amides; Humans; Inflammatory breast cancer; Inflammatory Breast Neoplasms - genetics; Inflammatory Breast Neoplasms - metabolism; Inflammatory Breast Neoplasms - pathology; Secretome; Synchrotron FTIR microspectroscopy; Synchrotrons; Tumor Microenvironment; Tumor-Associated Macrophages; Tumor-infiltrating monocytes
• ISSN: 0167-4889; 1879-2596
• DOI: 10.1016/j.bbamcr.2022.119367

Studies suggested that the pathogenesis of inflammatory breast cancer (IBC) is related to inflammatory manifestations accompanied by specific cellular and molecular mechanisms in the IBC tumor microenvironment (TME). IBC is characterized by significantly higher infiltration of tumor-associated macrophages (TAMs) that contribute to its metastatic process via secreting many cytokines such as TNF, IL-6, IL-8, and IL-10 that enhance invasion and angiogenesis. Thus, there is a need to first understand how IBC-TME modulates the polarization of TAMs to better understand the role of TAMs in IBC. Herein, we used gene expression signature and Synchrotron Fourier-Transform Infrared Microspectroscopy (SR-μFTIR) to study the molecular and biochemical changes, respectively of in vitro polarized TAMs stimulated by the secretome of IBC and non-IBC cells. The gene expression signature showed significant differences in the macrophage's polarization-related genes between stimulated TAMs. FTIR spectra showed absorption bands in the region of 1700–1500 cm−1 attributed to the amide I ν(C=O), & νAS (CN), δ (NH), and amide II ν(CN), δ (NH) proteins bands. Moreover, three peaks of different intensities and areas were detected in the lipid region of the νCH2 and νCH3 stretching modes positioned within the 3000–2800 cm−1 range. The PCA analysis for the second derivative spectra of the amide regions discriminates between stimulated IBC and non-IBC TAMs. This study showed that IBC and non-IBC TMEs differentially modulate the polarization of TAMs and SR-μFTIR can determine these biochemical changes which will help to better understand the potential role of TAMs in IBC. [Display omitted] •IBC patients showed high infiltration of MAC387+ TAMs.•IBC TAMs characterized by high mRNA expression of IL-10 and TLR1 versus non-IBC•SR-μFTIR able to discriminate between IBC and non-IBC TAMs