TY - JOUR
T1 - Indoleamine 2,3-dioxygenase 1 (IDO1) activity correlates with immune system abnormalities in multiple myeloma
AU - Bonanno, Giuseppina
AU - Mariotti, Andrea
AU - Procoli, Annabella
AU - Folgiero, Valentina
AU - Natale, Daniela
AU - De Rosa, Luca
AU - Majolino, Ignazio
AU - Novarese, Linda
AU - Rocci, Alberto
AU - Gambella, Manuela
AU - Ciciarello, Marilena
AU - Scambia, Giovanni
AU - Palumbo, Antonio
AU - Locatelli, Franco
AU - De Cristofaro, Raimondo
AU - Rutella, Sergio
PY - 2012/12/11
Y1 - 2012/12/11
N2 - Background: Multiple myeloma (MM) is a plasma cell malignancy with a multifaceted immune dysfunction. Indoleamine 2,3-dioxygenase 1 (IDO1) degrades tryptophan into kynurenine (KYN), which inhibits effector T cells and promote regulatory T-cell (Treg) differentiation. It is presently unknown whether MM cells express IDO1 and whether IDO1 activity correlates with immune system impairment.Methods: We investigated IDO1 expression in 25 consecutive patients with symptomatic MM and in 7 patients with either monoclonal gammopathy of unknown significance (MGUS; n=3) or smoldering MM (SMM; n=4). IDO1-driven tryptophan breakdown was correlated with the release of hepatocyte growth factor (HGF) and with the frequency of Treg cells and NY-ESO-1-specific CD8+ T cells.Results: KYN was increased in 75% of patients with symptomatic MM and correlated with the expansion of CD4+CD25+FoxP3+ Treg cells and the contraction of NY-ESO-1-specific CD8+ T cells. In vitro, primary MM cells promoted the differentiation of allogeneic CD4+ T cells into bona fide CD4+CD25hiFoxP3hi Treg cells and suppressed IFN-γ/IL-2 secretion, while preserving IL-4 and IL-10 production. Both Treg expansion and inhibition of Th1 differentiation by MM cells were reverted, at least in part, by d,l-1-methyl-tryptophan, a chemical inhibitor of IDO. Notably, HGF levels were higher within the BM microenvironment of patients with IDO+ myeloma disease compared with patients having IDO- MM. Mechanistically, the antagonism of MET receptor for HGF with SU11274, a MET inhibitor, prevented HGF-induced AKT phosphorylation in MM cells and translated into reduced IDO protein levels and functional activity.Conclusions: These data suggest that IDO1 expression may contribute to immune suppression in patients with MM and possibly other HGF-producing cancers.
AB - Background: Multiple myeloma (MM) is a plasma cell malignancy with a multifaceted immune dysfunction. Indoleamine 2,3-dioxygenase 1 (IDO1) degrades tryptophan into kynurenine (KYN), which inhibits effector T cells and promote regulatory T-cell (Treg) differentiation. It is presently unknown whether MM cells express IDO1 and whether IDO1 activity correlates with immune system impairment.Methods: We investigated IDO1 expression in 25 consecutive patients with symptomatic MM and in 7 patients with either monoclonal gammopathy of unknown significance (MGUS; n=3) or smoldering MM (SMM; n=4). IDO1-driven tryptophan breakdown was correlated with the release of hepatocyte growth factor (HGF) and with the frequency of Treg cells and NY-ESO-1-specific CD8+ T cells.Results: KYN was increased in 75% of patients with symptomatic MM and correlated with the expansion of CD4+CD25+FoxP3+ Treg cells and the contraction of NY-ESO-1-specific CD8+ T cells. In vitro, primary MM cells promoted the differentiation of allogeneic CD4+ T cells into bona fide CD4+CD25hiFoxP3hi Treg cells and suppressed IFN-γ/IL-2 secretion, while preserving IL-4 and IL-10 production. Both Treg expansion and inhibition of Th1 differentiation by MM cells were reverted, at least in part, by d,l-1-methyl-tryptophan, a chemical inhibitor of IDO. Notably, HGF levels were higher within the BM microenvironment of patients with IDO+ myeloma disease compared with patients having IDO- MM. Mechanistically, the antagonism of MET receptor for HGF with SU11274, a MET inhibitor, prevented HGF-induced AKT phosphorylation in MM cells and translated into reduced IDO protein levels and functional activity.Conclusions: These data suggest that IDO1 expression may contribute to immune suppression in patients with MM and possibly other HGF-producing cancers.
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U2 - 10.1186/1479-5876-10-247
DO - 10.1186/1479-5876-10-247
M3 - Article
C2 - 23232072
AN - SCOPUS:84870660898
VL - 10
JO - Journal of Translational Medicine
JF - Journal of Translational Medicine
SN - 1479-5876
IS - 1
M1 - 247
ER -