Two Novel Mutations of the NPM1 Gene in Syrian Adult Patients with Acute Myeloid Leukemia and Normal Karyotype

Objective: Somatic mutations in exon 12 of the NPM1 gene is one of the most common genetic abnormalities in adult acute myeloid leukemia (AML), which is observed in 25-35% of AML patients and in 50-60% of patients with cytogenetically normal AML (CN-AML). Methods: We performed Sanger sequencing of exon 12 of the NPM1 gene, on 44 CN-AML patients to characterize NPM1 status. Results: In this study, NPM1 mutations were identified in 10 (22.7%) of the 44 CN-AML patients. Among the 10 patients with NPM1 mutations, type A NPM1 mutations were identified in 8 (80%) patients, whereas non-A type NPM1 mutations were observed in 2 (20%) patients. Two non-A type NPM1 mutations were not previously reported: c.867-868InsCGGA and c.861-862InsTGCA. These two novel mutant proteins display a nuclear export signal (NES) motif (L-xxx-L-xx-V-x-L) less frequently and L-x-Lx-V-xx-V-x-L it has been never seen before, yet. However, both novel mutations show a tryptophan loss at codon 288 and 290 at the mutant C-terminus which are crucial for aberrant nuclear export of NPM into the cytoplasm. Conclusions: This study suggests previously unreported NPM1 mutations may be non-rare and thus additional sequence analysis is needed along with conventional targeted mutational analysis to detect non type-A NPM1 mutations.     

The Clinicopathological Impact of Granulocyte-Macrophage Colony-Stimulating Factor Gene Expression and Different Molecular Prognostic Biomarkers in Egyptian Acute Myeloid Leukemia Patients

Background: Acute myeloid leukemia (AML) is characterized by clonal expansion of myeloid precursors with diminished capacity for differentiation. It develops as the consequence of a series of genetic changes in a hematopoietic precursor cell. Purpose This study aimed to investigate the correlation between GM-CSF gene expression and different molecular prognostic markers such as FLT3-ITD, NPM1 mutation A and CEBPA gene expression in 100 Egyptian AML patients. As well as, correlation with the response to induction therapy, DFS andOS in these patients. Methodology: Quantitative assessment of GM-CSF gene expression was performed by qRT-PCR. Additional prognostic molecular markers were determined as FLT3-ITD and NPM1 mutation A together with quantitative assessment of CEBPA gene expression by qRT-PCR. Results: Patients with high GM-CSF expression levels had better OS and DFS with p value 0.004 and 0.02, respectively. However, no statistically significant difference between low andhigh GM-CSF gene expression was found regarding the response to therapy (p value= 0.08). Most patients with low CEBPA expression had resistant disease together with poor OS and DFS (P value =     

Monosomal Karyotypes among 1147 Chinese Patients with Acute Myeloid Leukemia: Prevalence,Features and Prognostic Impact

A monosomal karyotype (MK), defined as ≥2 autosomal monosomies or a single monosomy in the presenceof additional structural abnormalities, was recently identified as an independent prognostic factor conveying anextremely poor prognosis in patients with acute myeloid leukemia (AML). In the present study, after excludingpatients with t(15;17), t(8;21), inv(16) and normal karyotypes, 324 AML patients with cytogenetic abnormalitieswere the main subject of analysis. The incidences of MK were 13% in patients aged 15 to 60 years and 18% inthose between 15 and 88 years old. MK was much more prevalent among elderly patients (p < 0.001) and wassignificantly associated with the presence of -7, -5, del(5q), abn12p, abn17p, -18 or 18q-, -20 or 20q- and CK (forall p < 0.001 except for abn12p p=0.009), and +8 or +8q was less frequent in MK+ AML(p=0.007). No correlationwas noted between monosomal karyotype and FAB subtype (p > 0.05); MK remained significantly associatedwith worse overall survival among patients with complex karyotype (p= 0.032); A single autosomal monosomycontributed an additional negative effect in OS of patients with structural cytogenetic abnormalities (P=0.008).This report presents the prevalence, feature and prognostic impact of MK among a large series of Chinese AMLpatients from a single center for the first time.     

Prognostic Relevance of DNMT3A,FLT3 and NPM1 Mutations in Syrian Acute Myeloid Leukemia Patients

Objective: Among all types of hematological neoplasms, acute myeloid leukemia (AML) has the highest death rate. Recently, cytogenetic and molecular genetics are crucial in the management, as a consequence of their effect on AML pathogenesis, classification, risk-stratification, prognosis and treatment. Methods: 100 Syrian adults with Normal Karyotype (NK) newly diagnosed  AML patients were included in this study, all cases confirmed histologically and immunohistochemically. Patients were divided into six subgroups using flow cytometry and cytological results. Polymerase chain reaction (PCR) was performed on exon 11-12 for FMS-like tyrosine kinase-3 internal tandem duplication (FLT3-ITD), exon 12 for Nucleophosmin1 (NPM1), and exon 23 for DNA methyltransferase 3A (DNMT3A) using target primers, the electropherograms were analyzed for gene mutations by comparing with the reference DNA sequence. Data were compared and aligned with different sequences using the NCBI BLAST Assembled Genomes tool. Results: FLT3-ITD, NPM1 and DNMT3A were detected in 24%, 22 % and 4%  patients respectively. M2 subtype had the most frequent incidence of diagnosis in AML. FLT3-ITD mutation patients had the highest mean of death cases, while the DNMT3A mutation patients had the lowest. On the other hand, the highest mean of remission was in patients with NPM1 mutation and the lowest in the carriers of the FLT3-ITD mutation. It was observed that the mean relapsed patients with FLT3-ITD and DNMT3A mutation was 3.4 and 2 months respectively, with no significant differences between (FLT3-ITD and DNMT3A) carriers and non-carriers relapsed. On the contrary,  the mean relapsed for NPM1 mutation carriers was 2.4  months with significant statistical differences. The mean survival time for patients with FLT3-ITD and NPM1  mutation was 5.9 months and 5.85 months respectively, with significant correlation. Between it was 5.88 months in DNMT3A patients with no significant differences. Finally, It was noted that the mean event free survival (EFS) of FLT3-ITD mutation patients was 4.818 months and the mean EFS of NPM1 mutation patients was 4.805 months, with significant statistical differences (p<0.05) between the mutation patients and non-mutated patients regarding to EFS, While this mean was not statistically significant in patients carrying DNMT3A mutation. Conclusion: Patients with FLT3-ITD and NPM1 mutations have the worst prognosis, where the presence of those mutations was significantly related to overall survival (OS) and EFS. Our study reflects that DNMT3A was not an extremely bad prognostic effect as an independent factor. We can declare according to this study that genetic mutation and variants detection could easily be incorporated into the regimen evaluation of AML patients.     

急性髓系白血病患者HOX11基因的表达及意义

目的 探讨HOX11基因在急性髓系白血病(acute myeloid leukemia,AML)中的表达及对预后的影响,为个体化治疗提供依据.方法 应用多重巢式RT-PCR方法对73例初诊AML患者的融合基因进行检测,对HOX11基因表达阳性和阴性的患者进行标准治疗后的疗效进行分析.结果 在预后良好组、预后中等组及预后不良组AML患者的标准治疗中,HOX11基因阳性表达患者的第一疗程完全缓解率(complete remission rate)并不高于阴性表达的患者(P＞0.05),而复发或死亡率(relapse or mortality rate)与HOX11基因阴性表达的患者比较差异有统计学意义(P＜0.05).结论 HOX11基因的表达可能影响AML患者的预后.     

The Relationship <i>BRCA1/2</i> Genes and Family History in Ovarian Cancers

BRCA1/2 genes are responsible for the hereditary breast and ovarian cancer syndrome. In this study, Turkish women with ovarian cancer were investigated in terms of demographic, clinicopathologic and family cancer stories according to their condition of the BRCA1/2 genes mutation carrier. During 2011 to 2017 in Turkey, BRCA1 and BRCA2 genes were analyzed in 38 women, who were diagnosed with cancer using Next Generation Sequencing technique. Pathogenic mutations were detected in 9 (23.7%) of patients. The diagnosis age for Ovarian cancer patients for BRCA1/2 mutation carriers was found higher. It was seen that mutations mostly occurred in the BRCA2 gene and frameshift mechanism and they were located in exon10 in the BRCA1 gene and especially in exon11 in the BRCA2 gene. According to the applied logistic regression model, it was found that patients with more than two relatives having cancer would have a 12.844 fold and high risk of being a BRCA1/2 mutation carrier. In women with ovarian cancer, BRCA1/2 gene mutations are observed more frequently in certain exons of these genes. BRCA1 mutation carriers are diagnosed with ovarian cancer earlier than BRCA2 mutation carriers. In hereditary ovarian cancers, besides BRCA1/2, many identified genes and many modifier candidate genes that are waiting to be discovered can cause this condition. In the family history, the numerical increase of cancerous relatives significantly increases the risk of BRCA1/2 carrying mutation.     

MDR1 RNA Expression as a Prognostic Factor in Acute Myeloid Leukemia: An Update

In order to confirm our initial report on the negative impact of MDR1 gene expression on the outcome of de novo acute myeloid leukemia (AML), we present an update of our prospective study with a larger number of patients and a longer duration of follow-up. At diagnosis, MDR1 RNA expression of the leukemic cells was negative in 37% and positive in 63% of the patients (N = 79). The complete remission rate of induction chemotherapy was 76% for MDR1 RNA negative and 54% for MDR1 RNA positive patients (p = 0.05). At a median observation duration of 33 months, the duration of overall survival was 19 months for the MDR1 RNA negative patients but only 8 months for the patients with MDR1 gene expression (p = 0.02). Thus the long-term data also indicate that MDR1 gene expression is an unfavourable prognostic factor in AML.     

Comparison of <i>UGT1A1</i> Polymorphism as Guidance of Irinotecan Dose Escalation in RAS Wild-Type Metastatic Colorectal Cancer Patients Treated With Cetuximab or Bevacizumab Plus FOLFIRI as the First-Line Therapy

Uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) polymorphism plays a crucial role in the increased susceptibility and toxicity of patients to irinotecan. This retrospective, observational study compared the clinical outcomes and adverse events (AEs) in RAS wild-type metastatic colorectal cancer (mCRC) patients treated with cetuximab or bevacizumab plus FOLFIRI with UGT1A1 genotyping and irinotecan dose escalation as the first-line therapy. In total, 173 patients with mCRC with RAS wild-type were enrolled. Among them, 98 patients were treated with cetuximab, whereas 75 patients were treated with bevacizumab. All patients received irinotecan dose escalation based on UGT1A1 genotyping. We compared the progression-free survival (PFS), overall survival (OS), objective response rates (ORRs), disease control rates (DCRs), metastatectomy, and severe adverse events (SAEs) between the two groups. The clinical effects of primary tumor sidedness and target therapy crossover were further analyzed. Over a median follow-up of 23.0 months [interquartile range (IQR), 15.0–32.5 months], no significant differences were observed between the cetuximab and bevacizumab groups in PFS [18.0 months vs. 14.0 months; 95% confidence interval (CI), 0.517–1.027; hazard ratio (HR), 0.729; p = 0.071], OS (40.0 months vs. 30.0 months; 95% CI, 0.410–1.008; HR, 0.643; p = 0.054), ORR (65.3% vs. 62.7%; p = 0.720), DCR (92.8% vs. 86.7%; p = 0.175), metastatectomy (36.7% vs. 29.3%; p = 0.307), and SAEs (p = 0.685). Regardless of primary tumor sidedness and target therapy crossover, no significant differences were noted in efficacy and safety between the two groups (all p > 0.05). Our results revealed that patients with wild-type RAS mCRC, regardless of biologics, with UGT1A1 genotyping can tolerate escalated doses of irinotecan and potentially achieve a more favorable clinical outcome without significantly increased toxicity.     

MicroRNA-204 Potentiates the Sensitivity of Acute Myeloid Leukemia Cells to Arsenic Trioxide

Although arsenic trioxide (ATO) is a well-known antileukemic drug used for acute promyelocytic leukemia treatment, the development of ATO resistance is still a big challenge. We previously reported that microRNA- 204 (miR-204) was involved in the regulation of acute myeloid leukemia (AML) cell apoptosis, but its role in chemoresistance is poorly understood. In the present study, we showed that miR-204 was significantly increased in AML cells after ATO treatment. Interestingly, the increased miR-204 level that was negatively correlated with ATO induced the decrease in cell viability and baculoviral inhibition of apoptosis protein repeatcontaining 6 (BIRC6) expression. Overexpression of miR-204 potentiated ATO-induced AML cell growth inhibition and apoptosis. Furthermore, miR-204 directly targets to the 3 -UTR of BIRC6. Upregulation of miR-204 decreased BIRC6 luciferase activity and expression, which subsequently enhanced the expression of p53. Restoration of BIRC6 markedly reversed the effect of miR-204 on the regulation of AML cell sensitivity to ATO. Taken together, our study demonstrates that miR-204 decreases ATO chemoresistance in AML cells at least partially via promoting BIRC6/p53-mediated apoptosis. miR-204 represents a novel target of ATO, and upregulation of miR-204 may be a useful strategy to improve the efficacy of ATO in AML treatment.     

Knockdown of IARS2 Inhibited Proliferation of Acute Myeloid Leukemia Cells by Regulating p53/p21/PCNA/eIF4E Pathway

IARS2 encodes mitochondrial isoleucine-tRNA synthetase, which mutation may cause multiple diseases. However, the biological function of IARS2 on acute myeloid leukemia (AML) has not yet been identified. In the present study, qRT-PCR was used to determine the expression of IARS2 in K562, THP1, and HL-60 leukemia cells. Additionally the mRNA levels of IARS2 in CD34 cells and AML cells obtained from patients were detected by qRT-PCR. IARS2-shRNA lentiviral vector was established and used to infect acute myeloid leukemia HL-60 cells. qRT-PCR and Western blot analysis were employed to assess the knockdown effect of IARS2. The proliferation rate and cell cycle phase of HL-60 cells after IARS2 knockdown were evaluated by CCK-8 assay and flow cytometry. The PathScan Antibody Array was used to determine the expression of cell cycle-related proteins in HL-60 cells after IARS2 knockdown. The expression of proliferation-related proteins in HL-60 cells after IARS2 knockdown was determined by Western blot analysis. Results showed that IARS2 expression was stable and much higher in HL-60, THP-1, and K562 leukemia cells and AML cells obtained from patients than that of human CD34 cells. Compared with cells of the shCtrl group, IARS2 was markedly knocked down in cells that were transfected with lentivirus encoding shRNA of IARS2 in HL-60 cells (p<0.05). IARS2 knockdown significantly inhibited the proliferation and induced cycle arrest at the G₁ phase in HL-60 cells. Additionally IARS2 knockdown significantly increased the expression of p53 and p21, and decreased the expression of PCNA and eIF4E in HL-60 cells. In conclusion, IARS2 knockdown can inhibit acute myeloid leukemia HL-60 cell proliferation and cause cell cycle arrest at the G₁ phase by regulating the p53/p21/PCNA/eIF4E pathways.     

Anticancer Effects of <i>Gleditsia sinensis</i> Extract in Rats Transplanted With Hepatocellular Carcinoma Cells

The thorns of Gleditsia sinensis have been historically used in Chinese medicine and are considered one of the fundamental therapeutic herbs. Its anticancer effects are currently being explored. Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer and still requires the development of new drugs with higher efficiency. By using a rat HCC model implanted with cancerous Walker-256 cells, the therapeutic effects of G. sinensis extract (GSE) were assessed, as well as its regulatory effects on miRNAs. GSE significantly restored liver morphology and dramatically induced cell apoptosis in HCC rats. In addition, miR-21/181b/183 was upregulated in the HCC liver, and the elevation of these miRNAs could be alleviated by both GSE and sorafenib. PTEN/TIMP3/PDCD4 downregulation was consistent with the targets of miR-21/181b/183 in the HCC liver, and the alteration of these target genes was restored by both GSE and sorafenib. TIMP3 effects on MMP-2/9 expression were also determined. Our present findings indicate the potential of GSE in HCC treatment, and expand the understanding of miRNA-related mechanisms in the anticancer effects of GSE.     

HIA与IA方案治疗初治急性髓系白血病的临床对比观察

目的分别用去甲氧柔红霉素（IDA）与HA方案[高三尖杉酯碱（HH）+阿糖胞苷（Ara-C）]组成的双诱导HIA方案与传统IA方案治疗初治急性髓系白血病,比较两组化疗方案的疗效及不良反应。方法HIA方案为：IDA 7 mg/（m²·d）,静脉滴注第1~3天;HH 2.5 mg/（m²·d）,静脉滴注,第1~5天;Ara-C 100 mg/（m²·d）,静脉滴注,第1~5天。IA方案为：IDA 10 mg/（m²·d）,静脉滴注,第1~3天; Ara-C 100 mg/（m²·d）,静脉滴注,第1~5天。结果HIA方案组第一疗程 74.4%（32/43）获CR,其中9例复发（早期复发1例,晚期复发8例）。IA方案组第一疗程73.3%(26/30）达CR,其中8例复发（早期复发5例,晚期复发3例）。两组在CR率和生存分析比较上差异均无明显统计学意义。但HIA方案组患者心脏不良反应发生率（2.3%）显著低于IA组（16.7%）。HIA方案化疗的不良反应主要为骨髓抑制和粒细胞缺乏所致感染,未见严重的非造血系统不良反应,尤其未加重心脏毒性,治疗过程中未发生早期死亡。结论HIA方案可以减少蒽环类药物的剂量,不加重心脏毒性,增加了患者的耐受能力,且不影响疗效。     

Mutation Analysis of IDH1/2 Genes in Unselected De novo Acute Myeloid Leukaemia Patients in India - Identification of A Novel IDH2 Mutation

IDH1/2 mutations which result in alternation in DNA methylation pattern are one of the most commonmethylation associated mutations in Acute myeloid leukaemia. IDH1/2 mutations frequently associated withhigher platelet level, normal cytogentics and NPM1 mutations. Here we analyzed IDH1/2 mutations in 200 newlydiagnosed unselected Indian adult AML patients and investigated their correlation with clinical, cytogeneticparameters along with cooperating NPM1 mutation. We detected 5.5% and 4% mutations in IDH1/2 genes,respectively. Except IDH2 c.515_516GG>AA mutation, all the other identified mutations were reported mutations.Similar to reported c.515G>A mutation, the novel c.515_516GG>AA mutation replaces 172nd arginine to lysinein the active site of the enzyme. Even though there was a preponderance of IDH1/2 mutations in NK-AML,cytogenetically abnormal patients also harboured IDH1/2 mutations. IDH1 mutations showed significant higherplatelet count and NPM1 mutations. IDH2 mutated patients displayed infrequent NPM1 mutations and lowerWBC count. All the NPM1 mutations in the IDH1/2 mutated cases showed type A mutation. The present datasuggest that IDH1/2 mutations are associated with normal cytogenetics and type A NPM1 mutations in adultIndian AML patients.     

Double Heterozygosity in the <i>BRCA1/2</i> Genes in a Turkish Patient with Bilateral Breast Cancer: A Case Report

BRCA1 and BRCA2 tumor suppressor genes are responsible for a quarter of hereditary breast cancers. Double heterozygous (DH) pathogenic variant carrier status in these genes is an extremely rare condition, especially in non-Askenazi individuals. We report a woman patient with bilateral breast cancer that carries DH disease-causing variants in BRCA1/2 genes. The 45-year-old patient who was followed up with the diagnosis of metachronous bilateral breast cancer was diagnosed with cancer at the age of 39 and 43, respectively. BRCA1/2 genes of the patient were evaluated using Next-Generation Sequencing. In the patient, the c.2800C>T (p.Gln934Ter) pathogenic variant in BRCA1 and the c.9648+1G>C likely pathogenic variant in BRCA2 were detected as DH. Segregation analysis in family members revealed that her two healthy siblings available for testing were heterozygous for either BRCA1 or BRCA2 variants, but her mother, who had a past diagnosis of ovarian cancer, was heterozygous for both BRCA1 and BRCA2 variants. Germline double heterozygosity in inherited cancer is a rare condition, and as far as we know it is reported for the first time from patient population in Turkey. Large-scale patient series are needed to determine the impact of double heterozygosity on diseases course, such as prognosis and treatment responses.     

Clinical Characteristics and Molecular Patterns of <i>RET</i>-Rearranged Lung Cancer in Chinese Patients

RET rearrangement has been proven as an oncogenic driver in patients with lung cancer. However, the prevalence, clinical characteristics, molecular features, and therapeutic options in RET-rearranged patients remain unclear, especially in Chinese lung cancer patients. We retrospectively collected 6,125 Chinese lung cancer patients who have been profiled using next-generation sequencing (NGS). The clinical demographics and molecular features of RET rearrangement-positive patients were analyzed. RET rearrangements were identified in 84 patients with a proportion of 1.4% in our cohort. The median age at diagnosis was 58 years, and it mainly occurred in females with adenocarcinoma histology. KIF5B-RET was the most frequent fusion type and accounted for 53.8% (57/106) of all RET fusions identified, with K15-R12 as the most frequent variant (71.9%). Among 47 RET+ patients profiled with larger panels, 72.3% (34/47) harbored concurrent alterations. TP53 ranked as the most common concurrent alteration, and concomitant EGFR oncogenic alterations were identified in seven patients. Moreover, an adenocarcinoma patient harboring concurrent RET fusion and EGFR L858R responded to combinatorial treatment of cabozantinib and osimertinib, with a progression-free survival of 5 months. Our study improved knowledge of clinical characteristics and molecular features of RET-rearranged lung cancers in China. It might be helpful to guide clinicians for more effective personalized diagnostic and therapeutic approaches.     

Differential Implications of CSF3R Mutations in t(8;21) and CEBPA Double Mutated Acute Myeloid Leukemia

BackgroundFew data are available exploring mutations of the colony-stimulating factor 3 receptor (CSF3R) in acute myeloid leukemia (AML) in an all-round and systematic manner. The purpose of this study was to analyze the CSF3R mutations (CSF3R_mut) in AML with recurrent genetic abnormalities for potential synergistic pathomechanism.Patients and MethodsWe retrospectively screened 1102 adult de novo AML patients with available next-generation sequencing (NGS) information on 132 genes related to hematologic disorders. The χ², Mann-Whitney U tests were used to analyze their associations with clinicopathologic characteristics, and a propensity score matching (PSM) followed by Kaplan-Meier method was applied to measure their prognostic effects.ResultsOverall, CSF3R_mut were detected in 40 (3.6%) of 1102 patients with adult de novo AML. CSF3R_mut were predominantly enriched in AML with the CEBPA double mutations (CEBPA_dm) (16/122, 13.1%), t(8;21) (12/186, 6.5%) and mutated RUNX1 (3/50, 6.0%), respectively. The CSF3R_mut loci and types differed according to AML subtypes, with frameshift-indels and premature stop confined in the t(8;21) AML [10/12 (83.3%)], and missense recurrently aggregated in the CEBPA_dm AML [16/16 (100%)]. Cases with CSF3R_mut had a lower WBC count versus those with CSF3R wild-type (CSF3R_wt) in the t(8;21) AML cohort, with a borderline significance [median 5.45 (range 0.94-20.30) × 10⁹/L) vs. 8.80 (range 0.96-155.00) × 10⁹/L, P = .046]. CSF3R_mut were non-significantly associated with higher WBC counts [median 33.6 (range 6.8-287.6) × 10⁹/L vs. 18.1 (range 1.7-196.0) × 10⁹/L, P = .156] and significantly with lower immunophenotypic CD15 positivity [0/8 (0%) vs. 44/80 (55%), P = .009] as compared to CSF3R_wt in the CEBPA_dm AML cohort. After propensity score matching followed by Kaplan-Meier analysis, CSF3R_mut cases had comparable disease-free survival (DFS) and overall survival (OS) to those with CSF3R_wt (P = .607 and P = .842, respectively) in the t(8;21) AML cohort. By contrast, CSF3R_mut showed an inclination towards inferior DFS compared to CSF3R_wt in the CEBPA_dm AML cohort [median DFS 19.8 (95%CI 3.1-36.5) months vs. not reached (NR), P = .086]. No significant difference was found for OS between CSF3R_mut and CSF3R_wt cases (P = .943).ConclusionWe concluded that CSF3R_mut were frequently enriched in patients with t(8;21) and CEBPA_dm subtypes among AML, but showed divergent clinicopathologic features, mutation loci and types and differing prognostic aspects.     

Prognostic Impact of Extramedullary Infiltration in Pediatric Low-risk Acute Myeloid Leukemia: A Retrospective Single-center Study Over 10 Years

BackgroundThe impact of extramedullary infiltration (EMI) on the clinical outcomes of pediatric patients with acute myeloid leukemia (AML) are controversial.Patients and MethodsA total of 214 pediatric patients with low-risk AML were classified as having EMI (central nervous leukemia [CNSL] and/or myeloid sarcoma [MS]) and not having EMI. Patients with isolated MS before AML diagnosis by bone marrow examination were confirmed with histopathologic examination. For patients diagnosed with AML by bone marrow examination, a thorough physical examination and radiologic imaging were used to confirm MS.ResultsMale gender, a high white blood cell count, the FAB-M5 subtype, t(8;21) and t(1;11) abnormalities, and c-KIT mutations were associated with EMI. The presence of MS was associated with a low complete remission rate (63.6% vs. 79.4%; P = .000) and poor 3-year relapse-free survival (RFS) (62.6% ± 7.5% vs. 87.0% ± 2.8%; P = .000) and 3-year overall survival (73.5% ± 7% vs. 88.8% ± 2.6%; P = .011). Multivariate analysis revealed that MS was a poor prognostic factor for RFS and overall survival. Bone infiltration was an independent risk factor for inferior RFS with MS. Patients with CNSL had a low complete remission rate (58.3% vs. 77.2%; P = .045); however, CNSL did not significantly affect the survival of low-risk patients with AML.ConclusionMS should be considered an independent risk factor to guide stratified treatment.     

A Combined Chemical,Computational, and In Vitro Approach Identifies SBL-105 as Novel DHODH Inhibitor in Acute Myeloid Leukemia Cells

Inhibition of the dihydroorotate dehydrogenase (DHODH) has been successful at the preclinical level in controlling myeloid leukemia. However, poor clinical trials warrant the search for new potent DHODH inhibitors. Herein we present a novel DHODH inhibitor SBL-105 effective against myeloid leukemia. Chemical characteristics were identified by ¹H NMR, ¹³C NMR, and mass spectroscopy. Virtual docking and molecular dynamic simulation analysis were performed using the automated protocol with AutoDock-VINA, GROMACS program. Human-recombinant (rh) DHODH was used for enzyme inhibition study. THP-1, TF-1, HL-60, and SKM-1 cell lines were used. MTT assay was used to assess cell viability. Flow cytometry was employed for cell cycle, apoptosis, and differentiation analysis. Chemical analysis identified the compound to be 3-benzylidene-6,7-benz-chroman-4-one (SBL-105). The compound showed high binding efficacy toward DHODH with a DG_bindingscore of −10.9 kcal/mol. Trajectory analysis indicated conserved interactions of SBL-105–DHODH to be stable throughout the 200-ns simulation. SBL-105 inhibited rh DHODH with an IC₅₀ value of 48.48 nM. The GI₅₀values of SBL-105 in controlling THP-1, TF-1, HL-60, and SKM-1 cell proliferations were 60.66, 45.33, 73.98, and 86.01 nM, respectively. A dose-dependent increase in S-phase cell cycle arrest and total apoptosis was observed by SBL-105 treatment in both cell types, which were reversed in the presence of uridine. The compound also increased the differentiation marker CD11b-positive populations in both THP-1 and TF-1 cells, which were decreased under uridine influence. SBL-105, a novel DHODH inhibitor, identified using computational and in vitro analysis, was effective in controlling AML cells and needs attention for further preclinical developments.