Corrigendum: NLRP3 Inflammasome Promotes the Progression of Acute Myeloid Leukemia via IL-1ß Pathway.

[This corrects the article DOI: 10.3389/fimmu.2021.661939.].

NLRP3 Inflammasome Promotes the Progression of Acute Myeloid Leukemia via IL-1ß Pathway.

NLRP3 inflammasome has been reported to be associated with the pathogenesis of multiple solid tumors. However, the role of NLRP3 inflammasome in acute myeloid leukemia (AML) remains unclear. We showed that NLRP3 inflammasome is over-expressed and highly activated in AML bone marrow leukemia cells, which is correlated with poor prognosis. The activation of NLRP3 inflammasome in AML cells promotes leukemia cells proliferation, inhibits apoptosis and increases resistance to chemotherapy, while inactivation of NLRP3 by caspase-1 or NF-κB inhibitor shows leukemia-suppressing effects. Bayesian networks analysis and cell co-culture tests further suggest that NLRP3 inflammasome acts through IL-1ß but not IL-18 in AML. Knocking down endogenous IL-1ß or anti-IL-1ß antibody inhibits leukemia cells whereas IL-1ß cytokine enhances leukemia proliferation. In AML murine model, up-regulation of NLRP3 increases the leukemia burden in bone marrow, spleen and liver, and shortens the survival time; furthermore, knocking out NLRP3 inhibits leukemia progression. Collectively, all these evidences demonstrate that NLRP3 inflammasome promotes AML progression in an IL-1ß dependent manner, and targeting NLRP3 inflammasome may provide a novel therapeutic option for AML.

NLRP3-activated bone marrow dendritic cells play antileukemic roles via IL-1ß/Th1/IFN-γ in acute myeloid leukemia.

The bone marrow microenvironment of acute myeloid leukemia (AML) characterized by immunosuppressive features fosters leukemia immune escape. Elucidating the immunosuppressive mechanism and developing effective immunotherapeutic strategies are necessary. Here, we found that the Th1% and IFN-γ level were downregulated in bone marrow of AML and NLRP3-activated BMDCs promoted CD4+ T cell differentiation into Th1 cells via IL-1ß secretion. However, IFN-γ-producing Th1 cells were not induced by NLRP3-activated BMDCs in the presence of the NLRP3 inflammasome inhibitor MCC950 or anti-IL-1ß antibody in vitro unless exogenous IL-1ß was replenished. This inhibitory effect on Th1 differentiation was also observed in Nlrp3-/- mice or anti-IL-1ß antibody-treated mice. Notably, elevated Th1 cell levels promoted apoptosis and inhibited proliferation in leukemia cells via IFN-γ secretion in vitro and in vivo. Thus, NLRP3-activated BMDCs promote the proliferation of IFN-γ-producing Th1 cells with antileukemic effects and may provide insight into the basis for leukemia immunotherapy in patients with AML.

Analysis of TET2 and EZH2 gene functions in chromosome instability in acute myeloid leukemia.

TET2 and EZH2 play important roles in the epigenetic regulation in many cancers. However, their specific roles in acute myeloid leukemia (AML) pathogenesis remain unknown. Here, the expression, methylation or mutation of EZH2 and TET2 was determined and further correlated with the levels of the chromosome instability (CIN) genes MAD2 and CDC20. We down-regulated EZH2 and TET2 in AML cell lines and assessed the effect on CIN using fluorescence in situ hybridization (FISH). Our results showed that TET2, EZH2, MAD2 and CDC20 were aberrantly expressed in AML patients. The expression level of MAD2 or CDC20 was positively correlated with that of TET2 or EZH2. Hypermethylation of the TET2 gene down-regulated its transcription. Down-regulation of EZH2 or TET2 expression inhibited apoptosis, affected MAD2 and CDC20 expression, and promoted CIN in AML cells. Decitabine treatment restored TET2 methylation and EZH2 transcription and ameliorated CIN in AML. Therefore, TET2 and EZH2 play a tumor-inhibiting role in AML that affects CIN via MAD2 and CDC20.

Investigation of NF-κB-94ins/del ATTG and CARD8 (rs2043211) Gene Polymorphism in Acute Lymphoblastic Leukemia.

NLRP3 inflammasome has been widely implicated in the development and progression of various hematological diseases. However, how NLRP3 inflammasome contributes to the pathogenesis and clinical features of acute lymphoblastic leukemia (ALL) is still unknown. Here, in ALL patients' bone marrow, we investigated the single-nucleotide polymorphisms (SNPs) and expression of NLRP3 inflammasome related genes, NF-κB, NLRP3, IL-1ß, IL-18, Caspase-1, and ASC. A total of 308 ALL patients and 300 healthy participants were included in this study. D allele and DD genotype under codominant model of NF-κB-94ins/del ATTG were showed as a protective factor in susceptibility of ALL. As for CARD8 (rs2043211), AT/TT genotype under dominant model and TT genotype under codominant model greatly increased the ALL susceptibility. We further studied the relationship between NLRP3 inflammasome genetic polymorphisms and clinical relevance. The results showed that DD genotype of NF-κB-94 ins/del ATTG and AT/TT genotype of CARD8 (rs2043211) contributed to lower WBC count and T-cell immunophenotype, respectively. Moreover, we also found that AT and TT genotypes of CARD8 (rs2043211), GT and TT genotypes of IL-1ß (rs16944), and TT genotype of IL-18 (rs1946518) were associated with higher mRNA expression of NLRP3 inflammasome related genes and secretion of downstream cytokines. In conclusion, NF-κB-94 ins/del ATTG and CARD8 (rs2043211) genotypes might serve as novel biomarkers and potential targets for ALL.

The Genetic Polymorphisms of NLRP3 Inflammasome Associated with T Helper Cells in Patients with Multiple Myeloma.

The pathogenesis of multiple myeloma (MM) remains unclear and the NLRP3 inflammasome has been more and more recognized in the progression of many diseases. To investigate the role of the NLRP3 inflammasome in MM, we determined the genetic polymorphisms and expression of NLRP3 inflammasome-related genes (IL-1ß, IL-18, CARD8, and NF-κB) in MM patients, and explored their clinical relevance. Furthermore, we investigated the relationship of the NLRP3 inflammasome with Th cells in MM. Our study showed that the CARD8-C10X (rs2043211) AT genotype contributed to the susceptibility of MM. CARD8-C10X TT patients had earlier clinical stage. The WBC count in the three CARD8 genotypes showed an increasing trend (AA

Increased Regulatory T Cells in Peripheral Blood of Acute Myeloid Leukemia Patients Rely on Tumor Necrosis Factor (TNF)-α-TNF Receptor-2 Pathway.

Acute myeloid leukemia (AML) harbors an immune suppression environment, featured by increased regulatory T cells (Tregs). The expression of tumor necrosis factor receptor-2 (TNFR2) on Tregs could be used to identify the maximally suppressive Treg population, and TNF-α furtherly promoted the expansion and function of Tregs via TNFR2 in mice. However, the role of TNF-α has not been determined in AML patients. In view of high levels of TNF-α and Tregs in AML patients, we hypothesized that the increased frequency of Tregs may rely on TNF-α-TNFR2 pathway. We investigated the levels of TNFR2+ Tregs and TNF-α secreted by T cells in peripheral blood (PB) of AML by flow cytometry and enzyme-linked immunosorbent assay, respectively. Our results showed the elevated plasma TNF-α in PB of newly diagnosed (ND) AML patients. The production of TNF-α by CD4+ T cells, especially by T helper (Th)17 cells was remarkably higher in ND AML patients than in complete remission (CR) patients and healthy controls. Then, we found that the circulating frequencies of CD4+CD25+ Tregs and CD4+CD25high Tregs in AML patients were elevated compared with those in healthy controls and CR patients. TNFR2 expression was much higher on Tregs in AML patients and was preferentially expressed on CD4+CD25high T cells. Furthermore, we confirmed that, in vitro, the additional TNF-α can increase the frequency of Tregs through TNFR2 in both AML patients and healthy controls. Summarily, in AML patients, the abnormally elevated level of TNF-α secreted by CD4+ T especially Th17 cells promoted the higher Tregs frequency via the TNF-α-TNFR2 pathway.

The genetic polymorphism and expression profiles of NLRP3 inflammasome in patients with chronic myeloid leukemia.

NLRP3 inflammasome has been recently reported as an important risk factor in the development of cancer. But the relationship between polymorphisms of NLRP3 inflammasome related genes and chronic myeloid leukemia (CML) is rarely reported. Therefore, the aim of the present study was to investigate the association of five genetic polymorphisms (NLRP3, IL-1ß, IL-18, CARD8 and NF-κB) in 267 CML patients and 344 healthy controls. We found that the AT genotype of CARD8 (rs2043211) was significantly higher compared to TT genotype in high and intermediate risk CML patients. IL-1ß (rs16944) polymorphism in early molecular response at 6 months was marginally different, with more GG and less AA genotype in BCR-ABLIS >1% group. IL-18 (rs1946518) polymorphism was significantly different with more GG genotype in BCR-ABLIS >1% group at 6 months. We also demonstrated that WBC count of newly diagnosed patients carrying AG genotype was significantly higher than that of GG or AA genotype of IL-1ß (rs16944). The onset age of patients carrying ins/ins genotype of NF-κB (rs28362491) was significantly older than that of ins/del and del/del genotype. Moreover, IL-1ß or NLRP3 mRNA expression was decreased and IL-18 mRNA expression was increased significantly in CML patients compared with controls. In conclusion, the genetic polymorphisms of NLRP3 inflammasome may be served as potential predictors for CML.

Insight to Pharmacokinetics of TKIs: Optimizing Practical Guidelines for Individualized Therapy.

OBJECTIVE: Tyrosine kinase inhibitors (TKIs) are widely used drugs which have high availability in reducing the activity of BCR-ABL1 tyrosine kinase, therefore they play an indispensable role in the treatment of Chronic myeloid leukemia (CML). Imatinib, dasatinib and nilotinib have been proved to have absolute bioavailability and stable blood concentration in humans. TKIs pharmacokinetics has close relationships with the clinical response and clinical treatment of CML. METHOD: We conducted a systematic PubMed search to look for studies relating to TKIs pharmacokinetics with proper inclusion/exclusion criteria. After looking through a large number of references, we investigated that different generations of TKIs could be influenced by many factors. We chose some typical factors which were closely linked to the common treatment of CML. These factors contain daily dose, diet, individual variability, drug-drug interaction, drugs resistance and drug withdrawal. RESULTS: By summarizing up these influence factors, we hope it can make a contribution to clinical therapy. Above all, the relationship between influence factors and the clinical therapeutic effect is the key point that our research pays attention to. CONCLUSION: This review highlights certain influence factors of TKIs clinical pharmacokinetics.

NLRP3 inflammasome activation plays a carcinogenic role through effector cytokine IL-18 in lymphoma.

Inflammasomes play important roles in the pathogenesis of tumors, but the roles of NLRP3 inflammasome in the lymphoma remain unclear. Activated NLRP3 inflammasome induces the maturation of its effector cytokine IL-18 which functions in the development of cancer. Here, we investigated the polymorphism and expression of NLRP3 inflammasome related genes and explored their function in lymphoma. We found that IL-18 (rs1946518) and NFκB94 ins/del (rs28362491) contributed to lymphoma susceptibility and allele G in IL-18 was significantly associated with the risk of lymphoma. The mRNA and plasma expression levels of IL-18 were significantly elevated in primary lymphoma patients and decreased after remission. NLRP3 inflammasome could be activated by ATP plus LPS in lymphoma cells accompanied with the increasing expression of NLRP3-related genes. NLRP3 inflammasome activation reduced the dexamethasone-induced proliferation-inhibiting effect by promoting cells into S phase. NLRP3 inflammasome activation promoted lymphoma cells proliferation and inhibited apoptosis through up-regulation of c-myc and bcl-2, and down-regulation of TP53 and bax, and then reduced the anti-tumor effect of dexamethasone. Similar with the activation of NLRP3, the effector cytokine IL-18 also had the proliferation-promoting, apoptosis-inhibiting and resistance-reducing effects on lymphoma cells via shifting the balance of c-myc/TP53 and bcl-2/bax. Moreover, neutralizing IL-18 has the opposite effects. In conclusion, NLRP3 inflammasome contributes to the susceptibility and plays a carcinogenic role through its effector cytokine IL-18 in lymphoma.

Aberrant NLRP3 inflammasome associated with aryl hydrocarbon receptor potentially contributes to the imbalance of T-helper cells in patients with acute myeloid leukemia.

Acute myeloid leukemia (AML) is a hematological malignancy in which the immune response serves a pivotal role in progression. Aryl hydrocarbon receptor (AHR) is involved in the modulation of the immune system, particularly in the differentiation of T-helper cell (Th) subsets. Although the NLR family pyrin domain-containing 3 (NLRP3) inflammasome has been implicated as essential in the pathogenesis of autoimmune and inflammatory diseases, the role it serves in the development of AML remains unknown. Therefore, in order to identify and describe the possible roles of AHR, as well as NLRP3 inflammasome, in the pathogenesis of AML and their relationship with Th subsets (Th1 Th22), the present study investigated the mRNA expression levels of AHR and NLRP3 inflammasome molecules in the peripheral blood and bone marrow. Concentrations of plasma IL-18 were also investigated in peripheral blood by ELISA, as well as the proportions of Th22 and Th1. In the present study, there were three groups: Newly diagnosed (ND) patients; complete remission (CR); and normal controls. A markedly increased expression of NLRP3 inflammasome molecules in bone marrow mononuclear cells (BMMCs) from newly diagnosed (ND) patients compared with patients in complete remission (CR) was identified. NLRP3 inflammasome molecules were also observed to be aberrantly expressed in peripheral blood (PB) mononuclear cells (PBMCs), accompanied with aberrant interleukin (IL)-18 levels in PB plasma. The relative level of IL-18 mRNA became normal after the ND patients with AML achieved CR. In bone marrow, the expression of AHR was significantly higher in ND patients than in CR patients. Furthermore, the expression level of NLRP3 inflammasome molecules was significantly correlated with AHR expression in patients with AML. In the Th subsets, a significantly increased proportion of Th22 in PB from ND patients compared with CR patients or controls was identified, accompanied with decreased Th1. It was concluded that the NLRP3 inflammasome, associated with AHR, was involved in the development of AML and may have influenced the differentiation of Th subsets.

Genetic polymorphisms of IL-18 rs1946518 and IL-1ß rs16944 are associated with prognosis and survival of acute myeloid leukemia.

BACKGROUND: Though the pathogenesis of AML is still unknown, accumulating evidence revealed that immune response plays a vital part in it. NLRP3 inflammasome as a component of immune system has been found related to several cancers. The single nucleotide polymorphisms (SNPs) of NLRP3 inflammasome genes may be related to pathogenesis and prognosis of AML. METHODS AND RESULTS: We determined polymorphisms of NLRP3 (rs35829419), CARD8 (rs2043211), IL-1ß (rs16944), IL-18 (rs1946518) and NF-κB -94 ins/del ATTG in de novo AML patients to find out whether they play roles in the susceptibility and severity of AML. In our study, 383 AML cases and 300 randomly selected healthy individuals were examined for the polymorphisms and expression of NLRP3 genes. IL-1ß (rs16944) polymorphism in different risk AML subgroups was found statistically different, with more GA genotype in favorable-risk cytogenetics group. We also demonstrated that the bone marrow blasts of patients carrying IL-18 (rs1946518) GG or GT genotype were higher than patients of TT genotype. IL-18 plasma level of patients with IL-18 (rs1946518) GT or TT genotype was higher than GG genotype. Moreover, the GT genotype of IL-18 (rs1946518) led to statistically poorer AML-specific survival. CONCLUSION: IL-1ß (rs16944) and IL-18 (rs1946518) may be served as potential predictors for AML.

Polymorphisms of Interlukin-1ß rs16944 confer susceptibility to myelodysplastic syndromes.

Genetic factors have been shown to be associated with Myelodysplastic syndromes (MDS) susceptibility. In recent years, the role of inflammation in the promotion of tumor growth is supported by a broad range of experimental and clinical evidence. But the relationship between polymorphisms in NOD-like receptor protein 3 (NLRP3) inflammasome and MDS is rarely reported. Thus, we conducted a case-control study, and genotyped five single nucleotide polymorphisms (SNPs) (NLRP3, IL-1ß, IL-18, CARD8, and NF-κB) in MDS patients and healthy controls. The association of different genotypes with patient characteristics was analyzed. Comparing MDS patients with controls, GG genotype of IL-1ß (rs16944) was observed to be associated with a significantly increased risk of MDS 78/166 (48.8%) vs 26/96 (27.0%), OR=2.1, CI (1.0-4.4). No significant association was identified regarding the rest of investigated polymorphisms and MDS susceptibility. Complex karyotypes were more frequent in patients with GG genotype of IL-1ß (rs16944). Patients with IL-1ß polymorphisms (rs16944) GG and GA had lower hemoglobin than those without. Patients with IL-1ß polymorphisms (rs16944) GG had higher IPSS scores than those without IL-1ß polymorphisms. In conclusion, our present data shows that the IL-1ß polymorphisms (rs16944) GG were frequently occurred in MDS. IL-1ß (rs16944) GG genotype might serve as a novel biomarker and potential targets for MDS.

Neuropathy correlated with imbalanced Foxp3/IL-17 in bone marrow microenvironment of patients with acute myeloid leukemia.

Bone marrow (BM) neural tissues are important components of bone marrow microenvironment and play important roles in normal hematopoiesis. Neuropathy of BM can cause immunological alteration in hematopoietic microenvironment. It also can induce the impairment of normal hematopoiesis and promote the development of hematologic diseases. In the present study, we determined the expression levels and clinical significances of nerve-related molecules [nestin, tyrosine hydroxylase (TH), Glial Fibrillary Acidic protein (GFAP) and S100B] and T helper-related molecules (IL-17, Foxp3) in BM of AML patients and controls by immunohistochemical analysis and RT-PCR. Our results showed that the positive rates and expression levels of nestin, TH, GFAP and IL-17 were significantly decreased while Foxp3 and the ratio of Foxp3/IL-17 were statistically elevated in BM of AML patients. We found that there were significantly positive correlations between nestin with TH and IL-17 in BM of AML patients. We also observed significantly negative correlations between nestin with TH and Foxp3/IL-17 ratio. Moreover, the expression of nestin was positively correlated with the overall survival of AML patients. Our study suggests that neuropathy together with imbalanced T helper immunology in bone marrow might play important roles in AML.