The immune system is important for elimination of residual leukemic cells during acute myeloid leukemia (AML) therapy. Anti-leukemia immune response can be inhibited by various mechanisms leading to immune evasion and disease relapse. Selected markers of immune escape were analyzed on AML cells from leukapheresis at diagnosis (N = 53). Hierarchical clustering of AML immunophenotypes yielded distinct genetic clusters. In the absence of DNMT3A mutation, NPM1 mutation was associated with decreased HLA expression and low levels of other markers (CLIP, PD-L1, TIM-3). Analysis of an independent cohort confirmed decreased levels of HLA transcripts in patients with NPM1 mutation. Samples with combined NPM1 and DNMT3A mutations had high CLIP surface amount suggesting reduced antigen presentation. TIM-3 transcript correlated not only with TIM-3 surface protein but also with CLIP and PD-L1. In our cohort, high levels of TIM-3/PD-L1/CLIP were associated with lower survival. Our results suggest that AML genotype is related to blast immunophenotype, and that high TIM-3 transcript levels in AML blasts could be a marker of immune escape. Cellular pathways regulating resistance to the immune system might contribute to the predicted response to standard therapy of patients in specific AML subgroups and should be targeted to improve AML treatment.

• Klíčová slova
• AML, DNMT3A, NPM1, TIM-3, immunophenotype,
• MeSH
• akutní myeloidní leukemie * diagnóza   genetika   MeSH
• antigeny CD274 genetika   MeSH
• biologické markery MeSH
• buněčný receptor 2 viru hepatitidy A genetika   MeSH
• DNA methyltransferasa 3A * genetika   MeSH
• lidé MeSH
• mutace MeSH
• nukleofosmin * genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny CD274 MeSH
• biologické markery MeSH
• buněčný receptor 2 viru hepatitidy A MeSH
• DNA methyltransferasa 3A * MeSH
• DNMT3A protein, human MeSH Prohlížeč
• NPM1 protein, human MeSH Prohlížeč
• nukleofosmin * MeSH

The nucleophosmin 1 (NPM1) gene is one of the most commonly mutated genes in acute myeloid leukemia (AML), occurring in approximately 60% of adult cytogenetically normal AML (CN-AML). To date, these mutations have only been detected in cells of the myeloid lineage, whereas the potential clonal involvement of the lymphoid lineage is controversial. In our study, NPM1 mutations were analyzed using the highly sensitive real-time quantitative polymerase chain reaction (RQ-PCR) method on fluorescence-activated cell-sorted (FACS) purified different circulating mature cell populations in patients with NPM1-mutated CN-AML. As expected, NPM1 mutations were found in myeloid blood cells, including CD14(+) monocytes and CD66b(+) granulocytes. However, we were also able to detect NPM1 mutations in CD19(+) B cells and CD3(-)14(-)16(+)56(+) natural killer (NK) cells, albeit at lower levels. Surprisingly, mutations were also detected in CD3(+) T cells from all analyzed patients. Our data demonstrate that NPM1-mutated CN-AML originates in an early stem cell with both lymphoid and myeloid differentiation potential.

• MeSH
• akutní myeloidní leukemie diagnóza   farmakoterapie   genetika   MeSH
• fenotyp MeSH
• genová dávka MeSH
• imunofenotypizace MeSH
• jaderné proteiny genetika   MeSH
• karyotypizace MeSH
• leukocyty metabolismus   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mutace * MeSH
• nukleofosmin MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• jaderné proteiny MeSH
• NPM1 protein, human MeSH Prohlížeč
• nukleofosmin MeSH

Nucleophosmin (NPM1) mutations in exon 12 are the most common genetic alternation in cytogenetically normal AML (CN-AML). Although mutation types A, B, and D represent the majority of cases, rare mutation variants of the NPM1 gene in individual patients do occur. In this study, we have evaluated a novel, DNA-based real-time quantitative polymerase chain reaction (RQ-PCR) for the detection of three of the most commonly occurring mutations and for six rare patient-specific mutation types, which represent 28% of all of the NPM1 mutations in our group of 25 CN-AML patients. Furthermore, the prognostic relevance of NPM1-based monitoring of minimal residual disease (MRD) in peripheral blood (PB), bone marrow (BM), and in specific cell subsets (CD34(+), CD34(-), CD34(dim)) of BM were evaluated. In 80% of the evaluable patients, a molecular relapse preceded a hematological relapse. Moreover, in this subset of patients, the molecular relapse occurred at a median of 97 days before the hematological relapse. Our compartment analysis showed a strong correlation between BM and PB (r = 0.907, P < 0.001) as well as a high copy number of mutated NPM1 in CD34(+) BM cells. In conclusion, we have demonstrated applicability of our presented RQ-PCR method for a large percentage of mutated NPM1 patients with CN-AML as well as the usefulness for long-term follow-up monitoring of MRD and the prediction of hematological relapse.

• MeSH
• akutní myeloidní leukemie diagnóza   genetika   MeSH
• antigeny CD34 MeSH
• buňky kostní dřeně MeSH
• dospělí MeSH
• genová dávka MeSH
• jaderné proteiny genetika   MeSH
• krevní buňky MeSH
• lidé středního věku MeSH
• lidé MeSH
• mutace * MeSH
• mutační analýza DNA metody   MeSH
• nukleofosmin MeSH
• prediktivní hodnota testů * MeSH
• prognóza MeSH
• recidiva MeSH
• reziduální nádor diagnóza   genetika   MeSH
• senioři MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antigeny CD34 MeSH
• jaderné proteiny MeSH
• NPM1 protein, human MeSH Prohlížeč
• nukleofosmin MeSH

Anaplastic large cell lymphoma (ALCL) is a T-cell malignancy predominantly driven by a hyperactive anaplastic lymphoma kinase (ALK) fusion protein. ALK inhibitors, such as crizotinib, provide alternatives to standard chemotherapy with reduced toxicity and side effects. Children with lymphomas driven by nucleophosmin 1 (NPM1)-ALK fusion proteins achieved an objective response rate to ALK inhibition therapy of 54% to 90% in clinical trials; however, a subset of patients progressed within the first 3 months of treatment. The mechanism for the development of ALK inhibitor resistance is unknown. Through genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) activation and knockout screens in ALCL cell lines, combined with RNA sequencing data derived from ALK inhibitor-relapsed patient tumors, we show that resistance to ALK inhibition by crizotinib in ALCL can be driven by aberrant upregulation of interleukin 10 receptor subunit alpha (IL10RA). Elevated IL10RA expression rewires the STAT3 signaling pathway, bypassing otherwise critical phosphorylation by NPM1-ALK. IL-10RA expression does not correlate with response to standard chemotherapy in pediatric patients, suggesting that a combination of crizotinib and chemotherapy could prevent ALK inhibitor resistance-specific relapse.

• MeSH
• anaplastický velkobuněčný lymfom farmakoterapie   genetika   metabolismus   patologie   MeSH
• antitumorózní látky farmakologie   terapeutické užití   MeSH
• biologické modely MeSH
• buněčné linie MeSH
• chemorezistence genetika   MeSH
• CRISPR-Cas systémy MeSH
• editace genu MeSH
• exprese genu MeSH
• imunohistochemie MeSH
• inhibitory proteinkinas farmakologie   terapeutické užití   MeSH
• krizotinib farmakologie   terapeutické užití   MeSH
• lidé MeSH
• nukleofosmin MeSH
• receptor interleukinu-10 - alfa-podjednotka genetika   metabolismus   MeSH
• signální transdukce účinky léků   MeSH
• transkripční faktor STAT3 metabolismus   MeSH
• tyrosinkinasy genetika   metabolismus   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antitumorózní látky MeSH
• inhibitory proteinkinas MeSH
• krizotinib MeSH
• NPM1 protein, human MeSH Prohlížeč
• nukleofosmin MeSH
• p80(NPM-ALK) protein MeSH Prohlížeč
• receptor interleukinu-10 - alfa-podjednotka MeSH
• STAT3 protein, human MeSH Prohlížeč
• transkripční faktor STAT3 MeSH
• tyrosinkinasy MeSH

OBJECTIVES: Interaction of leukemia cells with the bone marrow extracellular matrix promotes cell survival and resistance to chemotherapy. In this work, we analyzed integrin expression and adhesivity to fibronectin in primary cells from patients with acute myeloid leukemia. METHODS: Surface expression of integrins β1 and αVβ3 on primary leukemia cells (N = 46) was correlated with the stem cell marker CD34, as well as with cell adhesivity to fibronectin. The results were analyzed with regard to the mutational status of NPM1 and FLT3 genes. RESULTS: The integrin β1 was omnipresent, whereas αVβ3 was often more expressed on CD34-positive cells. In particular, higher αVβ3 expression on CD34+ cells was associated with NPM1 mutation (P = .0018). Monocytic leukemias had significantly higher αVβ3 expression compared to less maturated cases (P = .0008). Cells from patients with internal tandem duplications in FLT3 (FLT3-ITD) had lower adhesivity to fibronectin compared to cells with wild-type FLT3 (P = .031), specifically in less differentiated myeloblasts. Inhibition of a putative FLT3-ITD target, EZH2, increased cell adhesivity in MV4-11 cell line (P = .024). CONCLUSIONS: The integrin αVβ3 is expressed in particular on CD34+ cells with NPM1 mutation and might have a prognostic value in patients with mutated NPM1. FLT3-ITD is associated with lower cell adhesivity, especially in patients with less differentiated leukemias.

• Klíčová slova
• AML, CD34, FLT3-ITD, Fms-like tyrosine kinase, integrin,
• MeSH
• akutní myeloidní leukemie genetika   metabolismus   MeSH
• buněčná adheze MeSH
• buněčná membrána metabolismus   MeSH
• duplikace genu MeSH
• exprese genu MeSH
• fibronektiny metabolismus   MeSH
• integriny genetika   metabolismus   MeSH
• jaderné proteiny genetika   metabolismus   MeSH
• lidé MeSH
• mutace MeSH
• nádorové buněčné linie MeSH
• nukleofosmin MeSH
• tyrosinkinasa 3 podobná fms genetika   metabolismus   MeSH
• vazba proteinů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fibronektiny MeSH
• FLT3 protein, human MeSH Prohlížeč
• integriny MeSH
• jaderné proteiny MeSH
• NPM1 protein, human MeSH Prohlížeč
• nukleofosmin MeSH
• tyrosinkinasa 3 podobná fms MeSH

BACKGROUND/AIM: Minimal residual disease (MRD) in patients with acute myeloid leukemia (AML) before allogeneic hematopoietic stem cell transplantation (alloHSCT) can influence the results of therapy. With the aim of evaluating the potential role of pre-transplant MRD, we studied the impact of pre-transplant MRD level on the outcome of alloHSCT in patients with AML in complete remission (CR). PATIENTS AND METHODS: From 2/2005 to 9/2014, 60 patients with a median age of 54 years (range=30-66 years) with normal karyotype-AML harboring nucleophosmin 1 (NPM1) mutation [53% Fms-related tyrosine kinase receptor 3 internal tandem duplication (FLT3/ITD)-positive] in first (n=45) or second (n=15) CR underwent myeloablative (n=16) or reduced-intensity (n=44) alloHSCT (27% related, 73% unrelated). The MRD level was determined from bone marrow samples using real-time polymerase chain reaction for detection of NPM1 mutations before starting the conditioning regimen. RESULTS: The estimated probabilities of 3-year relapse, event-free survival (EFS) and overall survival (OS) for the whole cohort were 28%, 54%, and 59%, respectively. Statistical analysis showed that only age over 63 years and high MRD level affected alloHSCT outcome. Pre-transplant MRD level of 10 mutant copies of NPM1 per 10,000 Abelson murine leukemia viral oncogene homolog 1 (ABL) copies had the strongest statistical significance, and detection of higher MRD level (>10 NPM1-mutant copies) before alloHSCT was associated with increased overall mortality (hazard ratio=3.71; 95% confidence interval=1.55-9.06; p=0.004). The estimated probabilities of 3-year relapse, EFS, and OS were 6%, 72%, and 75% for patients with a low level of MRD and 48%, 35%, and 40% for patients with a higher level. CONCLUSION: Our data showed that the pre-transplant level of MRD in patients with normal karyotype AML harboring NPM1 mutation in CR provides important prognostic information, which as an independent prognostic factor predicts transplant results.

• Klíčová slova
• Acute myeloid leukemia, allogeneic hematopoietic stem cell transplantation, minimal residual disease, nucleophosmin 1 mutation,
• MeSH
• akutní myeloidní leukemie genetika   terapie   MeSH
• dospělí MeSH
• indukce remise * MeSH
• jaderné proteiny genetika   MeSH
• karyotyp MeSH
• lidé středního věku MeSH
• lidé MeSH
• mutace * MeSH
• nukleofosmin MeSH
• předoperační období MeSH
• senioři MeSH
• transplantace hematopoetických kmenových buněk * MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• jaderné proteiny MeSH
• NPM1 protein, human MeSH Prohlížeč
• nukleofosmin MeSH

Compared to solid tumors, the role of PD-L1 in hematological malignancies is less explored, and the knowledge in this area is mostly limited to lymphomas. However, several studies indicated that PD-L1 is also overexpressed in myeloid malignancies. Successful treatment of the acute myeloid leukemia (AML) is likely associated with elimination of the residual disease by the immune system, and possible involvement of PD-L1 in this process remains to be elucidated. We analyzed PD-L1 expression on AML primary cells by flow cytometry and, in parallel, transcript levels were determined for the transcription variants v1 and v2. The ratio of v1/v2 cDNA correlated with the surface protein amount, and high v1/v2 levels were associated with worse overall survival (p = 0.0045). The prognostic impact of PD-L1 was limited to AML with mutated nucleophosmin and concomitant internal tandem duplications in the FLT3 gene (p less than 0.0001 for this particular AML subgroup).

• Klíčová slova
• AML, CD34, FLT3-ITD, NPM1, PD-1, PD-L1 transcript, leukemia,
• MeSH
• akutní myeloidní leukemie krev   genetika   MeSH
• antigeny CD274 krev   genetika   metabolismus   MeSH
• jaderné proteiny genetika   MeSH
• lidé MeSH
• messenger RNA genetika   metabolismus   MeSH
• mutace MeSH
• nádorové biomarkery krev   genetika   metabolismus   MeSH
• nukleofosmin MeSH
• tyrosinkinasa 3 podobná fms genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antigeny CD274 MeSH
• CD274 protein, human MeSH Prohlížeč
• FLT3 protein, human MeSH Prohlížeč
• jaderné proteiny MeSH
• messenger RNA MeSH
• nádorové biomarkery MeSH
• NPM1 protein, human MeSH Prohlížeč
• nukleofosmin MeSH
• tyrosinkinasa 3 podobná fms MeSH

• MeSH
• akutní myeloidní leukemie diagnóza   genetika   terapie   MeSH
• alely MeSH
• exony MeSH
• genotyp MeSH
• jaderné proteiny genetika   MeSH
• kombinovaná terapie metody   MeSH
• lidé MeSH
• mladý dospělý MeSH
• mutace * MeSH
• nukleofosmin MeSH
• protokoly antitumorózní kombinované chemoterapie terapeutické užití   MeSH
• transplantace hematopoetických kmenových buněk MeSH
• Check Tag
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• Publikační typ
• dopisy MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH
• Názvy látek
• jaderné proteiny MeSH
• NPM1 protein, human MeSH Prohlížeč
• nukleofosmin MeSH

• Klíčová slova
• AML, NPM1, complete remission, transplantation,
• MeSH
• akutní myeloidní leukemie * genetika   mortalita   terapie   MeSH
• alografty MeSH
• dospělí MeSH
• jaderné proteiny genetika   MeSH
• karyotyp * MeSH
• lidé středního věku MeSH
• lidé MeSH
• míra přežití MeSH
• nukleofosmin MeSH
• přežití po terapii bez příznaků nemoci MeSH
• retrospektivní studie MeSH
• senioři MeSH
• transplantace hematopoetických kmenových buněk * MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• dopisy MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• jaderné proteiny MeSH
• NPM1 protein, human MeSH Prohlížeč
• nukleofosmin MeSH

BACKGROUND: NPM1 plasmid standards are required for absolute quantification of minimal residual disease in acute myeloid leukemia patients. The standards are usually obtained, next to commercially constructed gene fragments, from transgenic bacteria colonies. However, this procedure is laborious and very time consuming. METHODS AND RESULTS: We have developed a PCR method that speeds up, simplifies, and streamlines the process of preparing NPM1 plasmid standards. The method is based on a combination of three primers, two surrounding the usual NPM1 mutation position and one over the mutation site. With this method, we were able to clearly distinguish plasmids with at least 15 different NPM1 mutations from the wild-type NPM1 plasmid. CONCLUSIONS: With the new approach, preparing NPM1 plasmid standards is easier, identifying NPM1-positive colonies is possible in less than a day and moreover, for a lower price than commercially constructed gene fragments.

• Klíčová slova
• Acute myeloid leukemia, Cloning, Colony selection, Nucleophosmine 1, Quantitative PCR standards,
• MeSH
• akutní myeloidní leukemie * genetika   MeSH
• jaderné proteiny * genetika   MeSH
• lidé MeSH
• mutace genetika   MeSH
• nukleofosmin MeSH
• plazmidy genetika   MeSH
• reziduální nádor genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• jaderné proteiny * MeSH
• nukleofosmin MeSH