The Effects of Hypoxia on the Immune–Metabolic Interplay in Liver Cancer
Yubei He,
Han Xu,
Yu Liu,
Stefan Kempa,
Carolina Vechiatto,
Robin Schmidt,
Emine Yaren Yilmaz,
Luisa Heidemann,
Jörg Schnorr,
Susanne Metzkow,
Eyk Schellenberger,
Akvile Häckel,
Andreas Patzak,
Dominik N. Müller,
Lynn Jeanette Savic
Affiliations
Yubei He
Department of Radiology, Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität Zu Berlin, 13353 Berlin, Germany
Han Xu
Department of Radiology, Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität Zu Berlin, 13353 Berlin, Germany
Yu Liu
Department of Radiology, Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität Zu Berlin, 13353 Berlin, Germany
Stefan Kempa
Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 10115 Berlin, Germany
Carolina Vechiatto
Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 10115 Berlin, Germany
Robin Schmidt
Department of Radiology, Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität Zu Berlin, 13353 Berlin, Germany
Emine Yaren Yilmaz
Department of Radiology, Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität Zu Berlin, 13353 Berlin, Germany
Luisa Heidemann
Department of Radiology, Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität Zu Berlin, 13353 Berlin, Germany
Jörg Schnorr
Department of Radiology, Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität Zu Berlin, 13353 Berlin, Germany
Susanne Metzkow
Department of Radiology, Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität Zu Berlin, 13353 Berlin, Germany
Eyk Schellenberger
Department of Radiology, Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität Zu Berlin, 13353 Berlin, Germany
Akvile Häckel
Department of Radiology, Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität Zu Berlin, 13353 Berlin, Germany
Andreas Patzak
Institute of Translational Physiology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
Dominik N. Müller
Experimental and Clinical Research Center, A Joint Cooperation of Max Delbrück Center for Molecular Medicine and Charité-Universitätsmedizin Berlin, 13125 Berlin, Germany
Lynn Jeanette Savic
Department of Radiology, Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität Zu Berlin, 13353 Berlin, Germany
M2-like macrophages promote tumor growth and cancer immune evasion. This study used an in vitro model to investigate how hypoxia and tumor metabolism affect macrophage polarization. Liver cancer cells (HepG2 and VX2) and macrophages (THP1) were cultured under hypoxic (0.1% O2) and normoxic (21% O2) conditions with varying glucose levels (2 g/L or 4.5 g/L). Viability assays and extracellular pH (pHe) measurements were conducted over 96 hours. Macrophages were exposed to the tumor-conditioned medium (TCM) from the cancer cells, and polarization was assessed using arginase and nitrite assays. GC-MS-based metabolic profiling quantified TCM meta-bolites and correlated them with M2 polarization. The results showed that pHe in TCMs decreased more under hypoxia than normoxia (p p = 0.0120,0.1%VX2-TCM group: p = 0.0149, 0.1%HepG2-TCM group: p 0.1%VX2-TCMHG group: p = 0.0001, and 0.1%HepG2-TCMHG group: p < 0.0001). TCMs also induced M2 polarization under normoxic conditions, but the strongest M2 polarization occurred when both tumor cells and macrophages were incubated under hypoxia with high glucose levels. Metabolomics revealed that several metabolites, particularly lactate, were correlated with hypoxia and M2 polarization. Under normoxia, elevated 2-amino-butanoic acid (2A-BA) strongly correlated with M2 polarization. These findings suggest that targeting tumor hypoxia could mitigate immune evasion in liver tumors. Lactate drives acidity in hypoxic tumors, while 2A-BA could be a therapeutic target for overcoming immunosuppression in normoxic conditions.
