ASXL1 Mutations Research Articles

Elevated serum direct bilirubin is predictive of a poor prognosis for primary myelodysplastic syndrome.

The aim of this study was to assess the prognostic significance of serum direct bilirubin (DBIL) for patients newly diagnosed with myelodysplastic syndromes (MDS). The clinical, laboratory, and follow-up data of MDS patients were collected, and the associations of DBIL levels with overall survival (OS) and leukemia-free survival (LFS) were analyzed. In total, 262 MDS patients were assigned to the high DBIL level group or the normal DBIL level group in the retrospective study. High DBIL was associated with older age, reduced hemoglobin, higher levels of β2-microglobin, lactate dehydrogenase, and serum ferritin, along with the number of co-mutations (> 1) and a higher frequency of ASXL1, KIT, and KRAS mutations. Multivariate analyses found that high DBIL level was an independent adverse predictor for OS (p = 0.002, hazard ratio = 2.723, 95%CI = 1.442-5.143) but not for LFS (p = 0.057, hazard ratio = 1.678, 95%CI = 0.986-2.857). A novel nomogram based on DBIL, sex, age, β2-microglobulin, lactate dehydrogenase, the Revised International Prognostic Scoring System (IPSS-R) was constructed, which demonstrated superior accuracy compared with the IPSS-R (C-index, 0.790 vs. 0.731, respectively). An elevated DBIL level was identified as an independent adverse prognostic factor for MDS patients. An individualized prediction model was established and validated to improve prediction of OS and LFS.

Prognostic impact of 'multi-hit' versus 'single-hit' TP53 alteration in patients with acute myeloid leukemia: results from the Consortium on Myeloid Malignancies and Neoplastic Diseases.

While there is clear evidence to suggest poorer outcome associated with multi-hit (MH) TP53 mutation (TP53MT) compared to a single-hit (SH) mutation in lower-risk myelodysplastic syndrome (MDS), data are conflicting in both higher-risk MDS and acute myeloid leukemia (AML). We conducted an in-depth analysis utilizing data from ten US academic institutions to study differences in molecular characteristics and outcomes of SH (N=139) versus MH (N=243) TP53MT AML. Complex cytogenetics were more common in MH than in SH TP53MT AML (P<0.001); whereas ASXL1 (P<0.001), RAS (P<0.001), splicing factor (P=0.003), IDH1/2 (P=0.001), FLT3 ITD (P<0.001) and NPM1 (P=0.005) mutations clustered significantly with SH TP53MT AML. Survival after excluding patients who received best supportive care alone was dismal but not significantly different between patients with SH or MH disease (event-free survival: 3.0 vs. 2.20 months, respectively, P=0.22; overall survival: 8.50 vs. 7.53 months, respectively, P=0.13). In multivariable analysis, IDH1 mutation and allogeneic hematopoietic stem cell transplantation as a time-dependent covariate were associated with superior event-free survival (hazard ratio [HR]=0.44, 95% confidence interval [95% CI]: 0.19-1.01, P=0.05 and HR=0.34, 95% CI: 0.18-0.62, P<0.001) and overall survival (HR=0.24, 95% CI: 0.08-0.71, P=0.01 and HR=0.28, 95% CI: 0.16-0.47, P<0.001). Complex cytogenetics (HR=1.56, 95% CI: 1.01-2.40, P=0.04) retained an unfavorable significance for overall survival. Our analysis suggests that MH TP53MT is less relevant in independently predicting outcomes in patients with AML than in those with MDS.

Prognostic Significance and Treatment Response Associations of Genetic Mutations in Chronic Myelomonocytic Leukemia: A Retrospective Cohort Study

Background: This retrospective cohort study investigates the prognostic significance of genetic mutations in Chronic Myelomonocytic Leukemia (CMML) and their association with treatment responses among patients treated at a single institution, juxtaposed with a statewide dataset from Kentucky. Methods: The study includes 51 patients diagnosed with CMML under the World Health Organization criteria from January 2005 to December 2023. It examines their genomic profiles and subsequent survival outcomes. The analysis also categorizes patients into CMML-1 and CMML-2 subtypes and assesses survival differences between transformed and non-transformed cases. Results: Mutations in TET2, ASXL1, and SRSF2 were found to significantly influence survival, establishing their roles as critical prognostic markers. Additionally, the cohort from the University of Kentucky exhibited distinct survival patterns compared to the broader Kentucky state population, suggesting that demographic and treatment-related factors could underlie these variances. Conclusions: This research underscores the pivotal role of targeted genetic profiling in deciphering the progression of CMML and refining therapeutic strategies. The findings emphasize the necessity for advanced genetic screening in managing CMML to better understand individual prognoses and optimize treatment efficacy, thereby offering insights that could lead to personalized treatment approaches.

Cohesin RAD21 Gene Promoter Methylation in Patients with Acute Myeloid Leukemia.

Aberrant gene promoter methylation is one of the hallmarks of Acute Myeloid Leukemia (AML). RAD21 is an important gene, implicated in sister chromatids cohesion, DNA repair, the regulation of gene transcription, apoptosis and hematopoiesis. In this study, we investigate the possible implication of RAD21 promoter methylation in AML pathogenesis using a cohort of AML patients and a cohort of healthy individuals. RAD21 promoter methylation was found in 24% of patients and in none of the controls (p = 0.023), indicating a possible contribution to AML development. Interestingly, a statistically higher frequency of RAD21 methylation was observed in patients with trisomy 8 (9/21, 42.9%, p = 0.021), while none of the patients with aberrations of chromosome 11 had RAD21 gene promoter methylation (0%, 0/11, p = 0.048). Patients with monosomal and complex karyotypes showed low frequencies of RAD21 methylation (7.7% and 15.4%, respectively) without reaching statistical significance. Moreover, ASXL1 mutations were not found to be associated with RAD21 methylation. This is the first study which provides evidence for a possible pathogenetic role of RAD21 promoter methylation in AML development and especially in AML with trisomy 8. Further studies of RAD21 promoter methylation in large series of different AML genetic subgroups may contribute to the elucidation of AML pathogenesis and to the identification of new epigenetic biomarkers with diagnostic and prognostic value.

Myeloid Sarcoma of Conjunctiva in a patient with JAK2-positive myeloid neoplasm: two distinct myeloid neoplasms sequentially arising from a common precursor

Abstract Introduction/Objective Myeloid sarcoma (aka granulocytic sarcoma or chloroma), a rare type of myeloid neoplasm is characterized by the presence of myelogenous blastic cells outside of the bone marrow either before, during or after the development of leukemia. Presentation in the orbit is extremely rare, unlike other body parts. We report a case of myeloid sarcoma of conjunctiva in a patient with JAK2-positive myeloid neoplasm. Methods/Case Report An 84-year-old man presented with bilateral conjunctival masses which on biopsy showed diffuse involvement by blasts, immunohistochemically expressing positivity for myeloperoxidase, CD33, CD68, CD34 (partial), CD117 (partial) but were non-reactive to CD15, CD3 and PAX5. Next generation sequencing (NGS) revealed mutations in NRAS, ASXl1 and TET2 genes, consistent with the diagnosis of myeloid sarcoma (MS) of the conjunctiva. While patient’s past medical history included status post radiation and chemotherapy for prostate cancer and colonic adenocarcinoma respectively. it was also significant for a JAK 2 positive myeloproliferative neoplasm (MPN), six-years prior to current presentation. At the time he was treated with hydroxyurea for 5 years but developed neutrophilic leukocytosis and transfusion-dependent anemia. Subsequently a treatment regimen including ruxolitinib and pacritinib was initiated but without clinical and hematological improvements. NGS of the initial JAK2-positive MPN revealed ASXL1, JAK2 and TET2 mutations. Of note are the similarities and variations in the molecular signatures of patient’s initial MPN and current conjunctival MS. While the two neoplasms carried an identical TET2 mutation with highest variant allelic frequency, they are different in other mutations. Results (if a Case Study enter NA) NA Conclusion Our case illustrates an unusual manifestation of myeloid sarcoma localized to the conjunctiva. The identification of clonal relatedness on NGS with distinct mutations, adds complexity to our understanding of tumor origin. It highlights a series of events which may have contributed to this phenomenon, including consequence of therapy, clonal evolution with molecular discordance or origin as a totally independent entity. This report underscores the importance of genetic profiling in guiding prognosis and treatment strategies in such settings.

Generation and Characterization of Induced Pluripotent Stem Cells Carrying An ASXL1 Mutation.

Additional sex combs-like 1 (ASXL1) is an epigenetic modulator frequently mutated in myeloid malignancies, generally associated with poorprognosis. Current models for ASXL1-mutated diseases are mainly based on the complete deletion of Asxl1 or overexpression of C-terminal truncations in mice models. However, these models cannot fully recapitulate the pathogenesis of myeloid malignancies. Patient-derived induced pluripotent stem cells (iPSCs) provide valuable disease models that allow us to understand disease-related molecular pathways and develop novel targeted therapies. Here, we generated iPSCs from a patient with myeloproliferative neoplasm carrying a heterozygous ASXL1 mutation. The iPSCs we generated exhibited the morphology of pluripotent cells, highly expressed pluripotent markers, excellent differentiation potency in vivo, and normal karyotype. Subsequently, iPSCs with or without ASXL1 mutation were induced to differentiate into hematopoietic stem/progenitor cells, and we found that ASXL1 mutation led to myeloid-biased output and impaired erythroid differentiation. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that terms related to embryonic development, myeloid differentiation, and immune- and neural-related processes were most enriched in the differentially expressed genes. Western blot demonstrated that the global level of H2AK119ub was significantly decreased when mutant ASXL1 was present. Chromatin Immunoprecipitation Sequencing showed that most genes associated with stem cell maintenance were upregulated, whereas occupancies of H2AK119ub around these genes were significantly decreased. Thus, the iPSC model carrying ASXL1 mutation could serve as a potential tool to study the pathogenesis of myeloid malignancies and to screen targeted therapy for patients.

Diagnosis and Risk Stratification of Acute Myeloid Leukemia, Myelodysplasia -Related

To analyze the clinical and genetic characteristics of acute myeloid leukemia, myelodysplasia-related (AML-MR) patients and evaluate their prognostic risk stratification, to guide clinical treatment decisions and improve understanding of the biological characteristics and disease progression. The study analyzed cellular and molecular genetic information of 307 AML-MR patients, diagnosed based on clinical history, bone marrow morphology, cytogenetics, and molecular genetic abnormalities. The risk stratification followed the 2022 ELN guidelines. 57 cases (18.6%) met the AML-MR diagnostic criteria based on morphology and clinical history, 110 cases (37.2%) met the AML-MR diagnostic criteria based on cytogenetic results, and 210 cases (74.5%) met the AML-MR diagnostic criteria based on molecular testing results. Among different type of mutations, ASXL1 mutation was the most frequent, followed by SRSF2 and BCOR mutations. Except for 2 cases with incomplete data that could not be classified, 263 (86.2%) of the 305 patients were classified as poor prognosis, 20 (6.6%) were classified as good prognosis group, and 22 (7.2%) were classified as intermediate prognosis group. Molecular genetic information plays a crucial role in diagnosing AML-MR, highlighting the importance of genetics in diagnosis and prognosis. Most AML-MR patients fall into poor prognosis categories, necessitating early intensive and targeted therapy for better survival outcomes.

Early drivers of clonal hematopoiesis shape the evolutionary trajectories of de novo acute myeloid leukemia.

Mutations commonly found in AML such as DNMT3A, TET2 and ASXL1 can be found in the peripheral blood of otherwise healthy adults - a phenomenon referred to as clonal hematopoiesis (CH). These mutations are thought to represent the earliest genetic events in the evolution of AML. Genomic studies on samples acquired at diagnosis, remission, and at relapse have demonstrated significant stability of CH mutations following induction chemotherapy. Meanwhile, later mutations in genes such as NPM1 and FLT3, have been shown to contract at remission and in the case of FLT3 often are absent at relapse. We sought to understand how early CH mutations influence subsequent evolutionary trajectories throughout remission and relapse in response to induction chemotherapy. Here, we assembled a retrospective cohort of patients diagnosed with de novo AML at our institution that underwent genomic sequencing at diagnosis as well as at the time of remission and/or relapse (total n = 182 patients). Corroborating prior studies, FLT3 and NPM1 mutations were generally eliminated at the time of cytologic complete remission but subsequently reemerged upon relapse, whereas DNMT3A, TET2 and ASXL1 mutations often persisted through remission. Early CH-related mutations exhibited distinct constellations of co-occurring genetic alterations, with NPM1 and FLT3 mutations enriched in DNMT3A mut AML, while CBL and SRSF2 mutations were enriched in TET2 mut and ASXL1 mut AML, respectively. In the case of NPM1 and FLT3 mutations, these differences vanished at the time of complete remission yet readily reemerged upon relapse, indicating the reproducible nature of these genetic interactions. Thus, early CH-associated mutations that precede malignant transformation subsequently shape the evolutionary trajectories of AML through diagnosis, therapy, and relapse.

Inflammation in myelodysplastic syndrome pathogenesis

Inflammation is a key driver of the progression of preleukemic myeloid conditions, such as clonal hematopoiesis of indeterminate potential (CHIP) and clonal cytopenia of undetermined significance (CCUS), to myelodysplastic syndromes (MDS). Inflammation is a critical mediator in the complex interplay of the genetic, epigenetic, and microenvironmental factors contributing to clonal evolution. Under inflammatory conditions, somatic mutations in TET2, DNMT3A, and ASXL1, the most frequently mutated genes in CHIP and CCUS, induce a competitive advantage to hematopoietic stem and progenitor cells, which leads to their clonal expansion in the bone marrow. Chronic inflammation also drives metabolic reprogramming and immune system deregulation, further promoting the expansion of malignant clones. This review underscores the urgent need to fully elucidate the role of inflammation in MDS initiation and highlights the potential of the therapeutical targeting of inflammatory pathways as an early intervention in MDS.

Genomic mutation patterns and prognostic value in de novo and secondary acute myeloid leukemia: A multicenter study from China.

Acute myeloid leukemia (AML) can manifest as de novo AML (dn-AML) or secondary AML (s-AML), with s-AML being associated with inferior survival and distinct genomic characteristics. The underlying reasons for this disparity remain to be elucidated. In this multicenter study, next-generation sequencing (NGS) was employed to investigate the mutational landscape of AML in 721 patients from June 2020 to May 2023.Genetic mutations were observed in 93.34% of the individuals, with complex variations (more than three gene mutations) present in 63.10% of them. TET2, ASXL1, DNMT3A, TP53 and SRSF2 mutations showed a higher prevalence among older individuals, whereas WT1 and KIT mutations were more commonly observed in younger patients. BCOR, BCORL1, ZRSR2, ASXL1 and SRSF2 exhibited higher mutation frequencies in males. Additionally, ASXL1, NRAS, PPMID, SRSF2, TP53 and U2AF1 mutations were more common in patients with s-AML, which PPM1D was more frequently associated with therapy-related AML (t-AML). Advanced age and hyperleukocytosis independently served as adverse prognostic factors for both types of AML; however, s-AML patients demonstrated a greater number of monogenic adverse prognostic factors compared to dn-AML cases (ASXL1, PPM1D, TP53 and U2AF1 in s-AML vs. FLT3, TP53 and U2AF1 in dn-AML). Age and sex-related gene mutations suggest epigenetic changes may be key in AML pathogenesis. The worse prognosis of s-AML compared to dn-AML could be due to the older age of s-AML patients and more poor-prognosis gene mutations. These findings could improve AML diagnosis and treatment by identifying potential therapeutic targets and risk stratification biomarkers.

Clonal haematopoiesis is associated with major adverse cardiovascular events in patients with hypertrophic cardiomyopathy.

The heterogeneous phenotype of hypertrophic cardiomyopathy (HCM) is still not fully understood. Clonal haematopoiesis (CH) is emerging as a cardiovascular risk factor potentially associated with adverse clinical events. The prevalence, phenotype and outcomes related to CH in HCM patients were evaluated. Patients with HCM and available biospecimens from the Peter Munk Cardiac Centre Cardiovascular Biobank were subjected to targeted sequencing for 35 myeloid genes associated with CH. CH prevalence, clinical characteristics, morphological phenotypes assessed by echocardiogram and cardiac magnetic resonance and outcomes were assessed. All patients were evaluated for a 71-plex cytokines/chemokines, troponin I and B-type natriuretic peptide analysis. Major adverse cardiovascular events (MACE) were defined as appropriate implantable cardioverter-defibrillator shock, stroke, cardiac arrest, orthotopic heart transplant and death. Among the 799 patients, CH was found in 183 (22.9%) HCM patients with sarcomeric germline mutations. HCM patients with CH were more symptomatic and with a higher burden of fibrosis than those without CH. CH was associated with MACE in those HCM patients with sarcomeric germline mutations (adjusted hazard ratio [HR] 6.89, 95% confidence interval [CI] 1.78-26.6; p = 0.005), with the highest risk among those that had DNMT3A, TET2 and ASXL1 mutations (adjusted HR 5.76, 95% CI 1.51-21.94; p = 0.010). Several cytokines (IL-1ra, IL-6, IL-17F, TGFα, CCL21, CCL1, CCL8, and CCL17), and troponin I were upregulated in gene-positive HCM patients with CH. These results indicate that CH in patients with HCM is associated with worse clinical outcomes. In the absence of CH, gene-positive patients with HCM have lower rates of MACE.

Clinical Characteristics and Prognostic Relevance of Co-Mutated Genes in Acute Myeloid Leukemia Patients with FLT3 Mutations

To investigate the clinical characteristics and influence of co-mutated gene on acute myeloid leukemia patients (AML) with FMS-like tyrosine kinase-3 (FLT3) mutations. A total of 273 FLT3+ AML patients were enrolled, and the co-mutation gene data of the patients were collected to further analyze the prognosis of the patients. FLT3 and other common mutations were quantified by PCR amplification products direct sequencing and second-generation sequencing (NGS). When patients were divided into FLT3- ITD +, FLT3- TKD +, FLT3- ITD ++TKD + and FLT3- ITD -+TKD - group according to the type of FLT3 mutations, it was found that the frequencies of TET2, GATA2, NRAS and ASXL1 mutation were significantly different among the 4 groups (all P < 0.05). When patients were divided into allelic ratio (AR) ≥0.5 and <0.5 group, it was found that the frequencies of FLT3- ITD +, FLT3 -ITD - +TKD -, NPM1, NRAS and C-kit were significantly different between the two groups (all P < 0.05). When patients were divided into normal and abnormal karyotype group, it was found that the frequencies of FLT3- ITD +, FLT3- TKD +, NPM1, GATA2 and C-kit were significantly different between the two groups (all P < 0.05). The median overall survival (OS) of AML patients with FLT3 -TKD + (including FLT3- ITD ++TKD +) was longer than that of patients with FLT3- ITD + alone (P < 0.05). The OS and relapse-free survival (RFS) of AML patients with FLT3++TET2+ were both shorter than those of patients with FLT3++TET2- (both P < 0.05). The mutation frequencies of co-mutated genes are correlated with subtypes of FLT3, karyotype and AR. AML patients with FLT3 -TKD + have longer OS than patients with FLT3- ITD + alone, and patients with co-mutation of TET2 have shorter median OS and RFS.

Role of Neurotransmitters in Steady State Hematopoiesis, Aging, and Leukemia.

Haematopoiesis within the bone marrow (BM) represents a complex and dynamic process intricately regulated by neural signaling pathways. This delicate orchestration is susceptible to disruption by factors such as aging, diabetes, and obesity, which can impair the BM niche and consequently affect haematopoiesis. Genetic mutations in Tet2, Dnmt3a, Asxl1, and Jak2 are known to give rise to clonal haematopoiesis of intermediate potential (CHIP), a condition linked to age-related haematological malignancies. Despite these insights, the exact roles of circadian rhythms, sphingosine-1-phosphate (S1P), stromal cell-derived factor-1 (SDF-1), sterile inflammation, and the complement cascade on various BM niche cells remain inadequately understood. Further research is needed to elucidate how BM niche cells contribute to these malignancies through neural regulation and their potential in the development of gene-corrected stem cells. This literature review describes the updated functional aspects of BM niche cells in haematopoiesis within the context of haematological malignancies, with a particular focus on neural signaling and the potential of radiomitigators in acute radiation syndrome. Additionally, it underscores the pressing need for technological advancements in stem cell-based therapies to alleviate the impacts of immunological stressors. Recent studies have illuminated the microheterogeneity and temporal stochasticity of niche cells within the BM during haematopoiesis, emphasizing the updated roles of neural signaling and immunosurveillance. The development of gene-corrected stem cells capable of producing blood, immune cells, and tissue-resident progeny is essential for combating age-related haematological malignancies and overcoming immunological challenges. This review aims to provide a comprehensive overview of these evolving insights and their implications for future therapeutic strategies.

Clinical Validation of the Somatic FANCD2 Mutation (c.2022-5C>T) as a Novel Molecular Biomarker for Early Disease Progression in Chronic Myeloid Leukemia: A Case-Control Study.

Background: Chronic myeloid leukemia (CML) results from chromosomal translocation t(9;22) leading to the formation of the BCR-ABL fusion oncogene. CML has three stages: the chronic phase (CP), the accelerated phase (AP), and the blast crisis (BC). Tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of CML. TKIs work well in CP-CML, and these patients have a survival rate similar to the normal population, but TKIs are less effective in advanced-phase CML. Even with current advances in treatment, BC-CML patients have an average overall survival of less than a year. Early recognition of CML patients at risk of disease progression can help in timely interventions with appropriate TKIs or other therapeutic modalities. Although some markers of disease progression like BCR-ABL kinase domain, ASXL1, and GATA2 mutations are available, no universal and exclusively specific molecular biomarkers exist to early diagnose CML patients at risk of CML progression for timely therapeutic interventions to delay or minimize blast crisis transformation in CML. A recent study found that all BC-CML patients harbored the FANCD2 (c.2022-5C>T) mutation. Therefore, the current study was designed to detect this FANCD2 mutant in AP-CML (early progression phase) and to clinically validate its potential as a novel molecular biomarker of early CML progression from CP to AP. Methods: Our study comprised 123 CP-CML (control group) and 60 AP-CML patients (experimental group) from 2 oncology centers, from January 2020 to July 2023. Mean hemoglobin level, WBC count, platelet count, treatment type, hepatomegaly, splenomegaly, and survival status of AP-CML patients were significantly different from those of CP-CML patients. However, as these clinical parameters cannot help in the early detection of patients at risk of CML progression, there was a need for a clinically validated biomarker of AP-CML. DNA was extracted from the patients' blood samples, and the FANCD2 gene was sequenced using an Illumina NextSeq500 next-generation sequencer (NGS). Results: The NGS analysis revealed a unique splice-site mutation in the FANCD2 gene (c.2022-5C>T). This mutation was detected in the majority (98.3%) of AP-CML patients but in none of the CP-CML patients or healthy control sequences from genomic databases. The mutation was confirmed by Sanger sequencing. FANCD2 is a member of the Fanconi anemia pathway genes involved in DNA repair and genomic stability, and aberrations of this gene are associated with many cancers. Conclusions: In conclusion, our study shows that the somatic FANCD2 (c.2022-5C>T) mutation is a new molecular biomarker for early CML progression. We recommend further clinical validation of this biomarker in prospective clinical trials.

Analysis of risk factors for venous thromboembolism in patients with polycythemia vera and establishment of a prediction model

Objective: To investigate the risk factors of venous thrombosis in patients with polycythemia vera (PV) and establish a prediction model for venous thrombosis. Methods: PV patients with JAK2V617F gene mutation positive in the Second Hospital of Tianjin Medical University from September 2017 to November 2023 were retrospectively included. The patients were divided into groups according to whether they had venous thrombosis. After matching age and gender factors with propensity scores, 102 patients were included in the venous thrombosis group [46 males, 56 females, with a median age M (Q1, Q3) of 52 (44, 60) years] and 204 cases were included in the group without venous thrombosis [92 males, 112 females, with a median age of 52 (44, 59) years]. The clinical and laboratory characteristics, disease progression and incidence of gene mutation were compared between the two groups. The follow-up cohort ended on November 20, 2023, with a median follow-up [M (Q1, Q3)] of 11 (1, 53) years. Multivariate Cox risk model was used to analyze the influencing factors of venous thrombosis in PV patients, and establish a scoring system for the venous thrombosis risk factor prediction model of PV patients. Receiver operating characteristic (ROC) curve was used to evaluate the predictive efficiency of the model. Results: Hemoglobin concentration, the ratio of hematopoietic volume≥55%, neutrophil to lymphocyte ratio≥5, hypertension, subcostal spleen≥5 cm and secondary myelofibrosis in venous thrombosis group were higher than those in non-venous thrombosis group (all P<0.05). In addition, the proportion of history of thromboembolism, V617F gene mutation load (V617F%)≥50%, diabetes mellitus, ASXL1 mutation and secondary reticular silver staining≥3 in the venous thrombosis group were higher than those in the non-venous thrombosis group (all P<0.05). The proportion of PV patients with 3 or more gene mutations was 44.1% (45/102) in venous thrombosis group, which was higher than that of PV patients without venous thrombosis 29.9% (61/204) (P=0.014). The proportion of ASXL1 gene mutation in venous thrombosis group was 17.6% (18/102), which was higher than the 4.9% (10/204) in non-venous thrombosis group (P<0.001). Multivariate Cox risk model analysis showed that previous thromboembolism history (HR=2.031, 95%CI: 1.297-3.179, P=0.002), V617F%≥50% (HR=2.141, 95%CI: 1.370-3.347, P=0.001), ASXL1 mutation (HR=4.632, 95%CI: 1.497-14.336, P=0.008), spleen subcostal≥5 cm (HR=1.771, 95%CI: 1.047-2.996, P=0.033) are the risk factors of venous thrombosis in PV patients. According to HR values, a score system for predicting risk of venous thrombosis in PV patients was established: previous history of thromboembolism, V617F%≥50% and spleen subcostoal≥5 cm were assigned 1 point respectively, and ASXL1 mutation was assigned 2 points. Low risk group: score 0, medium risk group: score 1-2, high risk group: score≥3. The ROC curve analysis of the model for predicting venous thrombosis in PV patients showed that the area under the curve (AUC) was 0.807 (95%CI: 0.755-0.860), with the sensitivity of 88.2% and the specificity of 59.8% when the Youden index was 0.48. Conclusions: Previous thromboembolism history, V617F%≥50%, ASXL1 mutation, spleen subcostoal≥5 cm are risk factors of venous thrombosis in PV patients. The established prediction model has good prediction efficiency.

Chronic myelomonocytic leukemia with ring sideroblasts/SF3B1 mutation presents with low monocyte count and resembles myelodysplastic syndromes with-RS/SF3B1 mutation in terms of phenotype and prognosis.

Chronic myelomonocytic leukemia (CMML) and myelodysplastic syndromes (MDS) with ring sideroblasts (RS) or SF3B1 mutation (MDS-RS/SF3B1) differ in many clinical features, but share others, such as anemia. RS and SF3B1 mutation can also be found in CMML. We compared CMML with and without RS/SF3B1 and MDS-RS/SF3B1 considering the criteria established by the 2022 World Health Organization classification. A total of 815 patients were included (CMML, n=319, CMML-RS/SF3B1, n=172 and MDS-RS/SF3B1, n=324). The percentage of RS was ≥15% in almost all CMML-RS/SF3B1 patients (169, 98.3%) and most (125, 72.7%) showed peripheral blood monocyte counts between 0.5 and 0.9 x109/L and low risk prognostic categories. CMML-RS/SF3B1 differed significantly from classical CMML in the main clinical characteristics, whereas it resembled MDS-RS/SF3B1. At a molecular level, CMML and CMML-RS/SF3B1 had a significantly higher frequency of mutations in TET2 (mostly multi-hit) and ASXL1 (p=0.013) and CMML had a significantly lower frequency of DNMT3A and SF3B1 mutations compared to CMML/MDS-RS/SF3B1. Differences in the median overall survival among the three groups were statistically significant: 6.75 years (95% confidence interval [CI] 5.41-8.09) for CMML-RS/SF3B1 vs. 3.17 years (95% CI 2.56-3.79) for CMML vs. 16.47 years (NA) for MDS-RS/SF3B1, p<0.001. Regarding patients with CMML and MDS, both with SF3B1 mutation, survival did not significantly differ. CMML had a higher risk of transformation to acute myeloid leukemia (24% at 8 years, 95%CI 19%-30%). CMML-RS/SF3B1 mutation resembles MDS-RS/SF3B1 in terms of phenotype and clearly differs from CMML. The presence of ≥15% RS and/or SF3B1 in CMML is associated with a low monocyte count. SF3B1 mutation clearly improves the prognosis of CMML.

Multi-target measurable residual disease assessed by error-corrected sequencing in patients with acute myeloid leukemia: An ALFA study

The evaluation of measurable residual disease (MRD) in acute myeloid leukemia (AML) using comprehensive mutation analysis by next-generation sequencing (NGS) has been investigated in several studies. However controversial results exist regarding the detection of persisting mutations in DNMT3A, TET2, and ASXL1 (DTA). Benchmarking of NGS-MRD taking into account other molecular MRD strategies has to be done. Here, we performed error-corrected-NGS-MRD in 189 patients homogeneously treated in the ALFA-0702 study (NCT00932412). Persistence of non-DTA mutations (HR = 2.23 for RFS and 2.26 for OS), and DTA mutations (HR = 2.16 for OS) were associated with poorer prognosis in multivariate analysis. Persistence of at least two mutations in complete remission (CR) was associated with a higher cumulative incidence of relapse (CIR) (HR = 3.71, p < 0.0001), lower RFS (HR = 3.36, p < 0.0001) and OS (HR = 3.81, p = 0.00023) whereas persistence of only one mutation was not. In 100 analyzable patients, WT1-MRD, but not NGS-MRD, was an independent factor for RFS and OS. In the subset of 67 NPM1 mutated patients, both NPM1 mutation detection (p = 0.0059) and NGS-MRD (p = 0.035) status were associated with CIR. We conclude that detectable NGS-MRD including DTA mutations correlates with unfavorable prognosis in AML. Its integration with alternative MRD strategies in AML management warrants further investigations.

PTPN11variants in chronic myelomonocytic leukemia: Phenotypic and prognostic correlates.

6513 Background: PTPN11 (Ch12q24) is a proto-oncogene that codes for SHP2, a regulatory protein tyrosine phosphatase that impacts RAS/MAPK signaling. Germline variants have been described in juvenile myelomonocytic leukemia, while somatic variants have been associated with inferior survival in acute myeloid leukemia. PTPN11 variants are infrequent in chronic myelomonocytic leukemia (CMML), and their impact on disease phenotype and survival remains unclear. Methods: After IRB approval, 396 molecularly annotated CMML patients at Mayo Clinic were screened for somatic PTPN11 variants within 12 months of diagnosis while still in chronic phase disease. Overall (OS), acute myeloid leukemia (AML)-free survival (LFS), and predictors of survival were estimated using standard statistical measures. Results: 396 patients (median age 71 years; males 67%) with CMML were considered; pathogenic PTPN11 variants were seen in 12 (3%) with a median VAF of 20.5% (range: 4-50): A72T (n = 2), F285S (n = 2), and A72S (n = 2). Variants were most likely to be seen in the N-terminal SH2 domain (n = 7), followed by the PTP domain (n = 6), and the C-terminal SH2 domain (n = 1). PTPN11 variants clustered with CMML-2 (p = 0.02), higher absolute neutrophil count (p = 0.04), peripheral blood (p = 0.06) and bone marrow (p = 0.02) blast %, older age (p &lt;0.01), and were less likely to have SRSF2 comutations (p = 0.02). After a median follow-up of 18 months (range 0-193), 253 (64%) deaths and 68 (17%) AML transformations were recorded. PTPN11 variants negatively and independently impacted both OS (median 13 vs. 31 months; p &lt;0.01) and LFS (AML events: 42% (5/12) vs. 16% (63/384); p &lt;0.01). In age-adjusted multivariate analysis restricted to genetic risk factors, survival was negatively affected by abnormal karyotype and mutations involving PTPN11, DNMT3A, and SETBP1, and positively by TET2 mutations. All but SETBP1 retained significance in the presence of additional independent risk factors, namely male sex (p &lt;0.01) and leukocyte count (p &lt;0.01); HR in the latter analysis was 4.3 for PTPN11, 2.8 for DNMT3A, and 1.6 for abnormal karyotype. A similar analysis for LFS identified, as risk factors, PTPN11 (p = 0.01), DNMT3A (p &lt;0.01), and ASXL1 (p = 0.03) mutations, as well as bone marrow blast % (p &lt;0.01), absolute monocyte count ≥10 (p = 0.02), and immature circulating myeloid cells (p &lt;0.01). Conclusions: The current study identifies PTPN11 and DNMT3A mutations as independent risk factors for both OS and LFS in CMML. In regard to additional genetic risk factors, OS was positively affected by TET2 mutations and negatively by abnormal karyotype, while LFS was negatively affected by ASXL1 mutations.

Results and exploratory biomarker analyses of a phase II study CHANGEABLE: Combination of HX008 and niraparib in germ-line-mutated metastatic breast cancer.

1084 Background: The combination of poly (ADP-ribose) polymerase inhibitors and immune-checkpoint inhibitors demonstrated synergistic antitumor activity in preclinical studies. Here we report the efficacy, safety, and biomarker analyses of the combination of niraparib and PD-1 inhibitor HX008 in metastatic breast cancer (MBC) patients with germline DDR gene mutations in a phase II trial (CHANGEABLE). Methods: Eligible patients had histologically confirmed MBC with at least one measurable disease and germline pathogenic/suspected pathogenic mutations in DDR genes. Patients were enrolled into two cohorts: the main cohort (HER2-negative MBC patients with gBRCA1/2, gPALB2, gCHEK2) and the exploration cohort (MBC patients with gDDR gene mutations and brain metastases). Simon's Two-Stage design was used for recruiting patients in the main cohort. Patients with HER2-negative MBC received niraparib 200 mg qd combined with HX008 200 mg q3w, while HER2-positive patients received additional anti-HER2 TKI pyrotinib 400mg qd if having brain metastases, until disease progression. The primary endpoint was ORR. NGS of tissue and ctDNA were performed for exploratory biomarker analyses. Results: As of January 12, 2024, 37 patients were enrolled. In the main cohort with gBRCA1/2 mutations (n = 28), ORR was 78.6% (22/28), with 3 patients having complete response. DCR was 96.4% (27/28). Median PFS was 7.3 months (95%CI 4.2 to 10.4). According to Simon's Two-Stage design, since two patients with gCHEK2 mutations in the first stage had only stable disease, the recruitment was terminated. One patient with gPALB2 mutation had stable disease and the remaining one is in the screening process. In the patients having brain metastases (exploration cohort), ORR was 40% (2/5) and DCR was 80% (4/5). The most common treatment-related adverse events of grade 3 or higher were anemia (13 [35.1%]), thrombocytopenia (4 [10.8%]), and neutropenia (3 [8.1%]). No treatment-related deaths were reported. In the biomarker analysis, NGS of 700 genes was performed on 24 patients with gBRCA1/2 mutations in the main cohort. No significant difference was found in ORR or PFS between gBRCA1 and gBRCA2 mutations. Somatic mutations in XPO1 (16 patients (73%), 15/18 PR+CR, 1/4 SD+PD) showed significant correlation with response. Somatic TP53 mutations are significantly correlated with shorter PFS, while ASXL1 mutations are significantly correlated with longer PFS. Four somatic mutations (AR_c.1418_1420del, AR_c.231_239dup, 2 DUSP22 mutations) showed a consistent trend of decreasing in PD samples, while NF1_c.3198-4dup showed a consistent trend of increasing in PD samples. Conclusions: The combination of niraparib and HX008 demonstrated promising clinical benefits with a tolerable safety profile in MBC patients with germline BRCA1/2 mutations, even in patients with brain metastases. Clinical trial information: NCT04508803 .

Latest results of a phase 2 study of IMM01 combined with azacitidine (AZA) as the first-line treatment in adults with higher risk myelodysplastic syndromes (MDS).

6510 Background: Patients diagnosed with higher-risk myelodysplastic syndrome (MDS) have poor prognosis. Azacitidine (Aza) has been shown to prolong survival in patients with treatment-naive, higher-risk MDS compared to a menu of standard of care options. IMM01 is a fusion protein comprising a recombinant signal regulatory protein α (SIRPα) and IgG1, exerting anti-tumor effects by inhibiting the "Don't eat me" signal and activating the "Eat me" signal, leading to robust antibody-dependent cellular phagocytosis (ADCP). Methods: This is an open-label, multi-center, phase 2 study (NCT05140811) that evaluated safety and efficacy of IMM01 in combination with AZA as the first-line treatment for patients with untreated higher-risk MDS. Enrolled patients were aged ≥18 years with intermediate to very high risk MDS, as defined by the Revised International Prognostic Scoring System (IPSS-R) score &gt;3.5, and were not eligible for stem cell transplant or intensive chemotherapy. Patients were received intravenous IMM01 at a dosage of 2.0mg/kg/week and subcutaneous AZA at a dosage of 75 mg/m2 on days1-7 per 28-day cycle. Results: By the cutoff-day of Dec 22, 2023, 57 patients were enrolled in the study. The median age was 64 (30-83) years, with 41 (71.9%) being male, and 55 (96.5%) having an ECOG of ≥1. Based on risk classification per IPSS-R, 43.9% were high risk (HR) and 31.6% were very high risk (vHR). At baseline, the median levels of blood counts were 69 (35-136)g/L for hemoglobin, 43 (2-409)×109/L for platelets and 0.8 (0.1-8.6)×109/L for neutrophils. The median duration of follow-up was 12.8 months (95%CI:9.7-15.3). Among the 51 efficacy evaluable patients, overall response rate (ORR) was 64.7%, including 29.4% complete response (CR) rate, 15.7% marrow CR (mCR) with hematologic improvement (HI), 5.9% HI and 13.7% mCR alone. The median time to response (TTR) was 1.9 months (95%CI:1.8-2.8) and the median duration of response (DoR) was not reached(NR). The median of progression-free survival (PFS) was not reached, with an estimated 12-month PFS of 54.4% (95% CI, 31.4-72.6). NGS analysis identified common mutations in DNMT3A, ASXL1, U2AF1 and RUNX1. Notably, NPM1 mutations significantly correlate with treatment response, particularly achieving CR. The most common ≥G3 treatment related adverse events (TRAEs) (≥10%) included leukopenia (78.9%), thrombocytopenia (66.7%), neutropenia (66.7%), lymphopenia (56.1%), anemia (43.9%), infection (15.8%) and pneumonia (10.5%). Without using of a low priming dose, the Grade ≥3 hemolysis was rare (only 1.8%). Conclusions: IMM01 (without low-dose priming) combined with AZA were well tolerated and showed exciting efficacy results in patients with treatment-naive higher-risk MDS. Clinical trial information: NCT05140811 .