Novel insights into exosome-induced, tumor-associated inflammation and immunomodulation.
The immune system of cancer patients is often suppressed. Accumulating evidence suggests that exosomes released from tumor cells may play an essential role in this process but the mechanisms are not fully understood. Here we review recent papers showing that exosomes trigger the release of cytokines/chemokines from immune cells. We suggest that this process will either result in the stimulation of anti-tumor immune reactions or in a systemic immunosuppression. The direction appears to be largely dependent on the duration of interactions between immune cells and exosomes leading to the accumulation of inflammatory factors, i.e. on the length of the exposure to these factors. We propose that a long-term interaction of the immune system with elevated levels of tumor exosomes contributes to the development of immunosuppression in cancer patients.
Translational Immunology, D015, German Cancer Research Center, DKFZ, 69120 Heidelberg, Germany. Electronic address: p.altevogt@dkfz-heidelberg.de.
Peter
P
Altevogt
Translational Immunology, D015, German Cancer Research Center, DKFZ, 69120 Heidelberg, Germany.
Niko P
NP
Bretz
Translational Immunology, D015, German Cancer Research Center, DKFZ, 69120 Heidelberg, Germany; Skin Cancer Unit, German Cancer Research Center DKFZ, Heidelberg, Germany; Department of Dermatology, Venereology and Allergology, University Medical Center Mannheim, Ruprecht-Karl University of Heidelberg, 69120 Heidelberg, Germany.
Johannes
J
Ridinger
Skin Cancer Unit, German Cancer Research Center DKFZ, Heidelberg, Germany; Department of Dermatology, Venereology and Allergology, University Medical Center Mannheim, Ruprecht-Karl University of Heidelberg, 69120 Heidelberg, Germany.
Jochen
J
Utikal
Skin Cancer Unit, German Cancer Research Center DKFZ, Heidelberg, Germany; Department of Dermatology, Venereology and Allergology, University Medical Center Mannheim, Ruprecht-Karl University of Heidelberg, 69120 Heidelberg, Germany.
Viktor
V
Umansky
D000818:Animals; D016207:Cytokines / Q000276:immunology; D055354:Exosomes / Q000276:immunology*; D006801:Humans; D056747:Immunomodulation / Q000276:immunology*; D007249:Inflammation / Q000276:immunology*; D009369:Neoplasms / Q000276:immunology*
D016207:Cytokines
Chemokines; Cytokines; Exosome signaling; Myeloid derived suppressor cells