scholarly journals The sympathomimetic agonist mirabegron did not lower JAK2-V617F allele burden, but restored nestin-positive cells and reduced reticulin fibrosis in patients with myeloproliferative neoplasms: results of phase II study SAKK 33/14

Haematologica ◽  
2018 ◽  
Vol 104 (4) ◽  
pp. 710-716 ◽  
Author(s):  
Beatrice Drexler ◽  
Jakob R. Passweg ◽  
Alexandar Tzankov ◽  
Martin Bigler ◽  
Alexandre PA Theocharides ◽  
...  
Keyword(s):  
Phase Ii ◽  
Phase Ii Study ◽  
Myeloproliferative Neoplasms ◽  
Jak2 V617f ◽  
Allele Burden

scholarly journals Effects of the Sympathicomimetic Agonist Mirabegron on Disease Course, Mutant Allele Burden, Marrow Fibrosis, and Nestin Positive Stem Cell Niche in Patients with JAK2-Mutated Myeloproliferative Neoplasms. a Prospective Multicenter Phase II Trial SAKK 33/14

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 3108-3108 ◽  
Author(s):  
Beatrice Drexler ◽  
Jakob Passweg ◽  
Martin Bigler ◽  
Alexandre PA Theocharides ◽  
Nathan Cantoni ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Phase Ii ◽  
Mutant Allele ◽  
Myeloproliferative Neoplasms ◽  
Jak2 V617f ◽  
Nerve Fibers ◽  
Allele Burden ◽  
Sympathetic Nerve Fibers ◽  
Bone Marrow Histology ◽  
Cell Niche

Abstract Myeloproliferative neoplasms (MPN) are clonal hematopoietic disorders characterized by aberrant proliferation of erythroid, megakaryocytic and myeloid lineages. They are associated with decreased survival, thromboembolic complications, hemorrhage and leukemic transformation. MPN can be subdivided into polycythemiavera(PV), essentialthrombocythemia(ET) and primary myelofibrosis (PMF). The JAK2-V617F mutation is present in 70-80% of all MPN patients. MPN is initiated and maintained by mutated hematopoietic stem and progenitor cells (HSPC). Bone marrow mesenchymal stem cells expressing the intermediate filament proteinnestin(nestin+ MSCs) that are innervated by sympathetic nerve fibers constitute an important component of the stem cell niche and regulate normal HSCs. Thesenestin+ MSCs are strongly reduced in bone marrow of JAK2-V617F positive MPN patients and in mice expressing JAK2-V617F due to damage of the sympathetic nerve fibers triggered by cytokines from the mutant cells. In a JAK2-V617F mouse model of MPN, treatment with a beta-3sympathicomimeticagonist corrected the damage inflicted by the MPN clones on their niches and ameliorated the MPN phenotype. To test the potentially beneficial effect on disease-control by modulating bone marrow niche cells in patients with MPN, we performed a phase II trial with the beta-3sympathicomimeticagonistmirabegron. Patients and Methods: The trial consisted ofmirabegrontreatment with 25 mg daily during the first week, followed by 50 mg daily for at least 24 weeks. Patients with acytohistologicallyconfirmed diagnosis of MPN and a JAK2-V617F allele burden >20% in granulocytes at study entry were eligible, if not treated with JAK2 inhibitors or interferon. Reduction of the JAK2-V617F mutant allele burden ³50% in granulocytes was defined as the primary end point. Secondary end points included changes in blood counts or MPN related symptoms. As a side study, bone marrow biopsies were quantified fornestin+ MSCs, fibrosis and CD34+ HSPCs. N=39 patients have been accrued in 10 institutions in Switzerland. Eight (21%) had ET, 22 (56%) PV, and 9 (23%) PMF. N=27 (69%) were male, the median age was 62 (Q1-Q3 53-72) years. Median mutated allele burden at study onset was 52% (Q1-Q3 33-73%). All patients had prior treatment, N=28 (72%) patients hadcytoreductivetreatment, the remaining patients hadantiaggregation, anticoagulation or phlebotomy. Results: No patient reached the primary endpoint of 50% reduction in allele burden, one patient achieved a 25% reduction by 24 weeks of treatment. Adverse events were mostly grade I or II on the CTCAE scale. Three patients had grade III events: two were considered to be at least possibly related to study medication. In the side study, 24 patients agreed to bone marrow biopsy prior to and at the end ofmirabegrontreatment and for 20 patients both measurements are available. In these patients an increase in thenestin+ MSCs cells from a median of 1.09 (Q1-Q3 0.38-3.27)/mm2 to 3.95 (Q1-Q3 1.98-8.79)/mm2 (p<0.0001, Wilcoxon signed-rank test) and a slight decrease of myelofibrosis from a median grade of 1.00 (Q1-Q3 0.50-3.00) to 0.75 (Q1-Q3 0.50-2.00) (p=0.02), were observed. The mean change in thenestin+ cells from baseline to week 24 was 3.52 (95% confidence interval 1.65-5.39)/mm2. Morphometric changes in thenestin+ MSCs were significant for PV (n=13, p=0.007) and PMF (n=5, p=0.04). Bone marrow CD34+ cells slightly increased from a median 2.50 (Q1-Q3 2.00-3.25) to 3.00 (Q1-Q3 2.00-3.75) (p=0.06). Conclusion: In this prospective phase II clinical trial treatment with the beta-3-sympathicomimetic agonistmirabegronfor 24 weeks failed to achieve the primary endpoint to reduce the JAK2-V617F mutant allele burden >50% in patients with MPN. However, an increase in thenestin+ MSCs in bone marrow and a slight decrease of myelofibrosis were found, which will be further investigated. Figure 1 Bone marrow histology of a patient before (week 0) and at the end ofmirabegron treatment (week 24). Upper panel,reticulin fibers are stained black by silver impregnation (Gomori). Lower panel, immunohistochemistry staining with antibodies against humannestin protein (brown staining). Note decrease inreticulin fibrosis and increase innestin+ cells after 24 weeks of treatment. Magnification: 200x. Figure 1. Bone marrow histology of a patient before (week 0) and at the end ofmirabegron treatment (week 24). Upper panel,reticulin fibers are stained black by silver impregnation (Gomori). Lower panel, immunohistochemistry staining with antibodies against humannestin protein (brown staining). Note decrease inreticulin fibrosis and increase innestin+ cells after 24 weeks of treatment. Magnification: 200x. Disclosures Theocharides: Novartis: Consultancy, Honoraria. Rüfer:Novartis: Consultancy, Speakers Bureau. Benz:Celgene: Consultancy. Tzankov:Novartis: Speakers Bureau; Abbott: Speakers Bureau. Skoda:Novartis: Consultancy, Speakers Bureau; Baxalta: Speakers Bureau; Shire: Consultancy, Speakers Bureau.

Significant Activity of the JAK2 Inhibitor, INCB018424 in Patients with Secondary, Post-Myeloproliferative Disorder (MPD) Acute Myeloid Leukemia (sAML): Results of An Exploratory Phase II Study.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 631-631 ◽  
Author(s):  
Farhad Ravandi ◽  
Srdan Verstovsek ◽  
Zeev Estrov ◽  
Jan A. Burger ◽  
Solly George ◽  
...  
Keyword(s):  
Phase Ii ◽  
Stable Disease ◽  
Research Funding ◽  
Phase Ii Study ◽  
Jak2 V617f ◽  
Jak2 V617f Mutation ◽  
Significant Activity ◽  
Stat Signaling ◽  
V617f Mutation ◽  
Grade 3

Abstract Abstract 631 Background: Mutations of JAK2 gene have been identified in a significant proportion of patients with MPDs with the selective JAK2 inhibitors demonstrating significant activity. Patients with AML following prior MPD (sAML) respond poorly to standard cytotoxic chemotherapy and have a poor outcome. Abnormalities of the Jak-Stat signaling pathway have also been identified in a number of other hematological malignancies; chromosomal translocations resulting in TEL-JAK2 constructs lead to the constitutive activation of STAT5, IL-3-independent cellular proliferation, and leukemogenesis. Similarly, infection with oncogenic viruses such as human T-cell lymphotrophic virus, type I, and Abelson murine leukemia viruses results in enhanced kinase activity of Jaks, possibly accounting for their leukemogenic potential. Furthermore, disrupted Jak-Stat signaling has been reported in a number of leukemias. Aim: To identify potential activity of INCB018424 in patients with advanced hematological cancers. Methods: We are conducting a phase II study of INCB018424 in patients with relapsed/refractory leukemias for which no standard therapies are anticipated to result in a durable remission. Patients with performance status 0,1,and 2 with adequate organ function and no active, uncontrolled intercurrent illness or infection receive INCB018424 orally at 25 mg BID daily for 4 weeks (cycle #1). Response is assessed after 2 cycles of treatment. Responding patients or patients with stable disease are allowed to continue until progression. Predetermined dose modifications to 15 mg or 10 mg BID are allowed for drug related toxicities. Results: Eighteen patients [median age, 68 years; (range, 53-88] with relapsed and refractory leukemias (9 de novo AML, 3 sAML, 2 ALL, 1 MDS, 2 CMML, 1 CML) have been treated. The median number of prior therapies is 2 (range,1 to 6). Five patients (1 with AML, 2 with sAML, and 3 with CMML) had the JAK2 V617F mutation. Cytogenetic abnormalities include diploid in 7, chromosome 5 and 7 in 5, t(2;9) in 1, and the Philadelphia chromosome in 2. Pts have received a median of 1 cycle of therapy (range, 1-5 cycles) with 8 pts having stable disease (3 for 2 cycles, 2 for 3 cycles, 1 for 4 cycles, and 2 for 5 cycles). Three patients (including 2 with sAML and 1 with CMML, all with JAK2 mutation) have had significant declines in their bone marrow blasts (to <5%) associated with significant decrease in the size of the spleen and clinical improvement. The regimen has been very well tolerated with only grade 3 side effects being elevation of liver enzymes in 2 patients (thought not to be related to the study drug) and grade 3 thrombocytopenia in 1 patient. Conclusion: INCB018424 has significant activity in sAML and CMML associated with JAK2 V617F mutation. Clinical studies combining it with chemotherapy in sAML are warranted. Disclosures: Ravandi: Incyte Corporation: Research Funding. Verstovsek:Incyte: Research Funding. Garrett:Incyte Corporation: Employment. Newton:Incyte Corporation: Employment.

Correlations Between TET2 Mutation and Clinicohematologic Parameters in Myeloproliferative Neoplasms

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 1455-1455
Author(s):  
Jung Sook Ha ◽  
Jae Hee Lee ◽  
Sung Gyun Park ◽  
Nam Hee Ryoo ◽  
Dong Suk Jeon ◽  
...  
Keyword(s):  
Conflicts Of Interest ◽  
Myeloproliferative Neoplasms ◽  
Direct Sequencing ◽  
Jak2 V617f ◽  
Putative Tumor Suppressor Gene ◽  
Allele Burden ◽  
Frame Shift ◽  
Mutational Status ◽  
Tet2 Mutation ◽  
Disease Specific

Abstract Abstract 1455 Background: Since the acquired somatic mutation, JAK2 V617F, was discovered as a first molecular marker of myeloproliferative neoplasms (MPN), and it has been detected variably in each MPN subtypes. However, JAK2 V617F does not found in all of MPN cases and not necessarily specific to a particular clinicpathologic entity. Recently, mutation of the putative tumor suppressor gene, Ten-Eleven-Translocation-2(TET2), has been identified in MPN patients. However, the frequency of TET2 mutation or its relationship with JAK2 V617F mutation or pathologic function in MPN has not been concluded, yet. The aim of our study was to evaluate the frequency of TET2 in MPN patients, and whether there is any correlation of TET2 mutation with JAK2V617F mutation or the clinicohematologic parameters. Materials and Methods: Total 99 adult MPN patients (18 PV, 62 ET, 11 PMF and 8 MPN unclassified) whose bone marrow cells had been stored from 2007 to 2010 at point of first diagnosis were included in this study. Hematological diagnoses and subtyping were reconfirmed according to the 2008 WHO classification and clinicohematologic datas were collected from patient records. Direct sequencing for TET2(exon3–11) and JAK2 (exons 12 and 14) were performed using an ABI 3730XL DNA analyzer. The JAK2V617F allele burdens were determined by pyrosequencing for samples available and MPL was analyzed by allele-specific PCR. Results: The overall TET2 mutational frequency was 12.1%, and disease-specific mutational frequencies were 22.2% in PV, 9.7% in ET and 18.2% in PMF. The found mutations included 11 mutations, 7 frame-shift (p.Lys95AsnfsX18, p.Gln967AsnfsX40, p.Lys1022GlufsX4, p.Asp1314MetfsX49, p.Gln1534AlafsX43, p.Tyr1618LeufsX4, p.Leu1609GlufsX45), 1 nonsense (p.Gly1735X), 1 missense (Q599R) and 2 splicing mutations (c.3409+1G>T, c.4044+2insT). Those mutations most frequently involved exon 3(four mutations) and exon 11(four mutaions), and rarely intron 3, intron 8 and exon 7. None of the mutations were associated with a karyotypically apparent 4q24 rearrangement. All patients were also screened for JAK2 V617F, and the overall JAK2 V617F positive rate was 68%(94.4% in PV, 69.4% in ET, 45.5% in PMF and 37.5% in MPN, unclassified). All TET2 mutations occurred in JAK2 V617F positive cases. JAK2 exon12 mutation was not found in all patients. MPL W515L was found in one ET patient who also carried JAK2V617F, but not TET2 mutation. Information on JAK2 V617F allele burden was available in 78 patients. Considering all 99 patients, the patient age, hematologic indexes (leukocyte count, neutrophil fraction, lymphocyte fraction, monocyte fraction, Hb, Hct and platelet count), the frequency of organomegaly, marrow fibrosis or thrombotic/hemorrhagic complications were not different according to carrying TET2 mutation. However, TET2 mutation was more frequently found in JAK2 V617F carriers than non-carriers (P=0.008), but JAK2 V617F allele burden did not correlated with the presence of mutant TET2. When analysis was performed for each PV, ET, and PMF (no TET2 mutation in MPN-unclassifiable patients), correlation between TET2 and JAK2 V617F mutational status was not found in each subtypes (P=0.078 in PV, P=0.099 in ET and P=0.182 in PMF). However, the JAK2 V617F allele burden was significantly higher in PMF harboring TET2 mutation than PMF patients did not (88.0 ± 4.3% vs 19.1 ± 28.7%, P=0.034). In statistical analysis for the correlations of clinicohematologic parameters with TET2 mutation in each PV, ET and PMF patients, only a few statistically significant results were identified. The presence of TET2 mutation was correlated with high Hct in PMF (47.4 ± 5.4 vs 25.5 ± 6.2, P=0.037), and TET2 positive ET patients showed relatively higher frequency of organomegaly compared to ET patients without TET2 mutation (50% vs 19.6%, P=0.018). Conclusions: The overall and disease-specific frequencies of TET2 mutation in our study are similar with previous studies, and frame-shift mutation is the most frequent mutation type. There is no specific relationship between JAK2 V617F and TET2 mutation occurrence, but TET2 mutant PMF has higher JAK2 V617F allele burden than non-mutant. TET2 mutation is also associated with a higher Hct in PMF and higher frequency of organomegaly in ET. Larger scale studies involving more MPN patients are needed. Disclosures: No relevant conflicts of interest to declare.

Pegylated Interferon-alfa-2a (PEG-IFN-α-2A; PEGASYS™) for Essential Thrombocythemia (ET) and Polycythemia Vera (PV): An Update of an Ongoing Phase II Study.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 3542-3542 ◽  
Author(s):  
Alfonso Quintás-Cardama ◽  
Hagop Kantarjian ◽  
Guillermo Garcia-Manero ◽  
Jorge Cortes ◽  
Marie Ann Richie ◽  
...  
Keyword(s):  
Phase Ii ◽  
Phase Ii Study ◽  
Philadelphia Chromosome ◽  
Jak2 V617f ◽  
Human Interferon ◽  
Clinical Activity ◽  
Significant Activity ◽  
Starting Dose ◽  
Grade 3 ◽  
Initial Starting

Abstract Therapy for patients with high-risk Philadelphia chromosome-negative myeloproliferative disorders (MPDs) involves the use of cytoreductive agents such as recombinant human interferon-alpha (IFN-α), hydroxyurea (HU), and anagrelide (AG). Despite the significant activity of IFN-α in MPDs, therapy with this agent is frequently hindered by poor tolerance and inconvenient dosing schedules. PEG-IFN-α is formulated by covalently attaching polymers of ethylene glycol to the native IFN-α molecule, which results in decreased renal excretion and increased serum half-life that allows for weekly administration with acceptable toxicity. Based on the superior pharmacokinetic profile of PEG-IFN-α-2a relative to conventional IFN-α, we designed a phase II study of subcutaneous PEG-IFN-α-2a (Pegasys) for patients with ET or PV. A total of 50 patients have been enrolled and treated thus far (22 ET, 28 PV). Median age is 53 years (range, 23–77) and time from diagnosis to PEG-IFN-α-2a 64 months (range, 1–348). Prior therapies (median 2; range 0–6) included HU (n=33), AN (n=22), phlebotomy (n=27), IFN-α (n=8: 5 oral and 3 sc), other (n=10). PEG-IFN-α-2a was the initial therapy in 4 patients. The JAK2 V617F mutation was detected in 11 (50%) of 22 ET and in 26 (93%) of 28 PV patients. Six (12%) patients had abnormal cytogenetics. Initial starting dose of PEG-IFN-α-2a was 450 mcg/week, but that was modified to the current starting dose of 90 mcg/week. Dose modifications are allowed according to response or toxicity. Patients are currently receiving 450 mcg (n=1), 360 mcg (n=1), 270 mcg (n=5), 180 mcg (n=11), 135 mcg (n=8), 90 mcg (n=9), and 45 mcg (n=5). After a median follow-up of 11 months (range, 2–28), 47 (94%) patients have responded. Complete response (CR) was achieved by 46 (92%) patients (for ET: platelets <440x109/L, off HU and AG, in the absence of thromboembolic events; for PV: Hb <15 g/dL, off HU and AG, no phlebotomy, with disappearance of splenomegaly) whereas 1 (2%) patient with PV had a partial response ([PR]; no phlebotomy, off HU and AG, but still palpable spleen). The mutant JAK2 V617F to total JAK2 ratio was determined by PCR (n=37) and by a quantitative pyrosequencing assay (n=30) prior to PEG-IFN-α-2a. JAK2 V617F mutational analysis was subsequently performed after 6 and 12 months into PEG-IFN-α-2a therapy in 20 and 10 patients, respectively. Nine (30%) of the 30 patients assessable for JAK2 V617V quantitation had >10% reduction in JAK2 V617F expression, including 2 (7%) in whom the mutant allele became undetectable. In addition, 4 (13%) patients had a 5%–10% reduction. JAK2 V617F quantitation has not been repeated yet in 9 patients. PEG-IFN-α-2a was well tolerated in most patients. Twenty-two episodes of grade 3–4 toxicity were reported, including neutropenia (n=11), elevated transaminases (n=4), and anemia, thrombocytopenia, depression, fatigue, infection, cardiac, and pain in 1 case each. Ten patients were taken off study, including 6 (12%) due to therapy-related toxicities: grade 3 neutropenia (n=1), fatigue (n=1), depression (n=1), ischemic retinopathy (n=1), dyspnea (n=1),and diarrhea (n=1). In summary, therapy with PEG-IFN-α-2a results in remarkable clinical activity and acceptable toxicity profile in patients with ET or PV. Significant reduction of JAK2 V617F allele burden occurred in a proportion of responders, suggesting selective targeting of the malignant clone.

The JAK2 46/1 Haplotype Analysis In Essential Thrombocythaemia and Polycythaemia Rubra Vera Reveals That CC Genotype Is Associated with a Higher JAK2V617F and c-MPL W515 Allele Burden

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 1977-1977
Author(s):  
Shameem Mahmood ◽  
Louise Mellish ◽  
Nicholas Lea ◽  
Austin G Kulasekararaj ◽  
Atiyeh Abdallah ◽  
...  
Keyword(s):  
Conflicts Of Interest ◽  
Myeloproliferative Neoplasms ◽  
Association Studies ◽  
Statistical Significance ◽  
Jak2 V617f ◽  
Tagging Snp ◽  
Jak2 Mutation ◽  
Allele Burden ◽  
Significant Difference ◽  
Jak2v617f Allele Burden

Abstract Abstract 1977 First 2 authors contributed equally. Background: Genomic-wide association studies have identified the germline 46/1 haplotype as a predisposing allele associated with JAK2V617F positive myeloproliferative neoplasms (MPN). The present study analysed data on 856 JAK2V617F positive patients, 326 of which had complete clinical data. Aims: To evaluate the JAK2 46/1 haplotype frequencies, JAK2V617F allele burden, c-MPL 515 mutation and risk of transformation. Methods: Genomic DNA from whole peripheral blood or bone marrow patient samples was analysed as follows: JAK2V617F allele burden by Q-PCR, JAK2 exon 12 mutations by Q-PCR and PCR fragment analysis, MPL W515 L and K mutations by allele specific PCR. The 46/1 JAK2 mutation susceptibility haplotype (46/1) tagging SNP rs12343867 (susceptibility allele C) were analysed by pyrosequencing. Results: The allele frequency for the 46/1 tag SNP rs1234867 in the 856 patients was calculated for the total JAK2V617F cohort (0.48) and the clinical entities ET (0.34) and PRV (0.44) confirming that the 46/1 haplotype is greatly over represented in JAK2V617F MPD patients as compared to published the control population (Wellcome Trust Case Control Consortium (WTCCC) (0.24). The Analysis of the 856 patients demonstrated that JAK2V617F and c-MPL W515L/K mutations co-existed in 16 patients(1.9%), the incidence of c-MPL W515L being twice as common as the c-MPL W515K mutations. There was no correlation between these mutations and age or 46/1 haplotype status. The JAK2V617F allele burden (AB) was lower in the c-MPL mutant patients, the average JAK2AB 31%. 3 out 4 c-MPL patients for which clinical information was available had a diagnosis of ET. No JAK2 exon 12 mutations were found in any of the 859 JAK2V617F positive samples suggesting that co-existing JAK2 exon 14 and exon 12 mutations are extremely rare. The genotypic data in ET patients showed: C/C 12%, C/T 44%, T/T 44% and their respective JAK2V617 allele burden (AB) were 46%, 32%, 29%. The genotype data in PRV patients: C/C 18%, C/T 53%, T/T 28.6% and their respective AB were 47%, 31% and 39%. The median AB was 32% (n=121) for ET and 37% (n=103) for PRV. Within a cohort of 255 patients (ET=138, PRV=117) 4% of ET and 6% of PRV patients transformed to acute myeloid leukaemia or myelofibrosis with no predominant haplotype association. In the ET patients, the median AB was 35%, there was no significant difference in the JAK2 V617F AB between those who transformed or not (p=0.45). Interestingly, on the whole ET group C/C genotype patients were more likely to have an allele burden >50% (p=0.058). In the PRV patients, the median AB was 48%. Again, the C/C genotype, PRV patients were more likely to have an AB>50% (p=0.06), although not reaching statistical significance. Conclusions: The 46/1 haplotype in both clinical entities ET and PRV demonstrated a higher allele burden in the C/C genotype in comparison to the other genotypes. No predominant haplotype predicted the risk of transformation to a more aggressive disease such as MF or AML. The analysis also showed that c-MPL W515K/L mutations can co-exist with JAK2V617F. The c-MPL W515K/L mutations did not exhibit a positive correlation with a preferential 46/1, but was associated with a lower allele burden. No co-existing exon 12 and exon 14 mutations were found, suggesting the rarity of this occurrence. Disclosures: No relevant conflicts of interest to declare.

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