Prognosis Of Adult Acute Myeloid Leukemia Research Articles

AML-683 Lymphoid Markers as Predictors of Adult Acute Myeloid Leukemia Prognosis

AML-683 Lymphoid Markers as Predictors of Adult Acute Myeloid Leukemia Prognosis

Recent advances in AML with mutated NPM1.

Nucleophosmin 1 (NPM1) mutation is one of the most prevalent genetic mutations in adult acute myeloid leukemia (AML) and is particularly predominant in AML with a normal karyotype. NPM1 is a chaperone protein that plays various roles in several cellular processes. Wild-type NPM1 is normally localized to the nucleus, whereas mutant NPM1 proteins exhibit altered cytoplasmic localization. Clinically, AML with mutated NPM1 without FLT3-ITD is associated with a higher complete remission rate and improved overall survival. AML with mutated NPM1 is categorized as a distinct genetic entity in the World Health Organization classification of hematopoietic malignancies due to its unique clinical and biological features. However, the precise roles of NPM1 in normal hematopoiesis and in AML development remain unclear. Recent studies have revealed various clinical applications of NPM1 mutations in AML treatment, particularly in measurable residual disease analyses that target mutant NPM1 transcripts and in potential therapeutic applications of menin inhibitors and XPO-1 inhibitors for AML with mutated NPM1. Thus, NPM1 mutation is highly significant in AML classification, prognosis, response assessment, and molecular targeted therapies. Here, we review recent progress in clinical and biological aspects of AML with mutated NPM1 including molecular targeted therapy.

Lymphoid markers as predictors of adult acute myeloid leukemia prognosis

Background Acute myeloid leukaemia (AML) constitutes the most prevalent aggressive leukaemia in adults, with uncontrolled proliferation of immature myeloid cells and a variety of clinical manifestations. Whereas most AML patients respond to chemotherapy initially, half of all patients relapse within 5 years of being diagnosed. Aim and objectives The present study aimed to investigate the prognostic value of co expression of lymphocytes markers in patients with acute myeloid leukemia as regarding clinical outcome and survival. Patients and methods The present study was enrolled at Hematology Unit at Nasser Institute Hospital. This is a retrospective study done on (50) patients aged from 18 to 65 years, completion of treatment (or part of treatment undertaken), and follow-up duration of at least six months after diagnosis. Results The present study results showed a statistically significant difference between patients who achieved complete remission and those who relapsed or were refractory to treatment in the lymphoid markers CD7 and CD19. CD7 was the most frequent lymphoid marker. The lymphoid marker CD4 was associated with a higher complete remission rate. CD19 was associated with the highest relapse rate. Conclusion CD7 was the most frequent lymphoid marker. The lymphoid marker CD4 was associated with a higher complete remission rate compared to CD7, CD5, CD2 and CD19; While CD19 was associated with the highest relapse rate

Clinical characteristics and prognosis analysis of patients with de novo ASXL1-mutated AML treated with the C-HUNAN-AML-15 protocol: A multicenter study by the South China Pediatric AML Collaborative Group.

ASXL1 mutation is an independent prognostic factor in adult acute myeloid leukemia (AML), but its effect on the prognosis of pediatric AML is poorly understood. This study aimed to investigate the clinical characteristics and prognostic factors of ASXL1-mutant pediatric AML from a large Chinese multicenter cohort. A total of 584 pediatric patients with newly diagnosed AML from 10 centers in South China were enrolled. The exon 13 of ASXL1 was amplified by polymerase chain reaction (PCR), and then analyzed the mutation status of the locus. (n = 59 for ASXL1-mut group, n = 487 for ASXL1-wt group). ASXL1 mutations were found in 10.81% of all patients with AML. A complex karyotype was significantly less common in the ASXL1-mut AML group than in the ASXL1-wt group (1.7% vs. 11.9%, p = 0.013). Furthermore, TET2 or TP53 mutations were predominantly found in the ASXL1+ group (p = 0.003 and 0.023, respectively). The 5-year overall survival (OS) and event-free survival (EFS) of the total cohort were 76.9% and 69.9%. In ASXL1-mut AML patients, a white blood cell (WBC) count ≥50 × 109 /L had significantly poorer 5-year OS and EFS than a WBC count <50 × 109 /L (78.0% vs. 44.6%, p = 0.001; 74.8% vs. 44.6%, p = 0.003, respectively), while receiving hematopoietic stem cell transplantation (HSCT) had a higher 5-year OS and EFS (84.5% vs. 48.5%, p = 0.024; 79.5% vs. 49.3%, p = 0.047, respectively). In the multivariate Cox regression analysis, patients with high-risk AML undergoing HSCT tended to have a better 5-year OS and EFS than those receiving chemotherapy as a consolidation (HR = 0.168 and 0.260, both p < 0.001), and WBC count ≥50 × 109 /L or failure to achieve complete response after the first course were independent adverse predictors of OS and EFS (HR = 1.784 and 1.870, p = 0.042 and 0.018; HR = 3.242 and 3.235, both p < 0.001). The C-HUANA-AML-15 protocol is a well-tolerated and effective in the treatment of pediatric AML. ASXL1 mutation is not an independent adverse prognosis predictor for survival in AML, whereas ASXL1-mut patients tend to have a poor prognosis if WBC count ≥50 × 109 /L, but they can benefit from HSCT.

Downregulation of GNA15 Inhibits Cell Proliferation via P38 MAPK Pathway and Correlates with Prognosis of Adult Acute Myeloid Leukemia With Normal Karyotype.

BackgroundThe prognosis of acute myeloid leukemia (AML) with a normal karyotype is highly heterogonous, and the current risk stratification is still insufficient to differentiate patients from high-risk to standard-risk. Changes in some genetic profiles may contribute to the poor prognosis of AML. Although the prognostic value of G protein subunit alpha 15 (GNA15) in AML has been reported based on the GEO (Gene Expression Omnibus) database, the prognostic significance of GNA15 has not been verified in clinical samples. The biological functions of GNA15 in AML development remain open to investigation. This study explored the clinical significance, biological effects and molecular mechanism of GNA15 in AML.MethodsReverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to detect the mRNA expression level of GNA15 in blasts of bone marrow specimens from 154 newly diagnosed adult AML patients and 26 healthy volunteers. AML cell lines, Kasumi-1 and SKNO-1, were used for lentiviral transfection. Cell Counting Kit-8 (CCK8) and colony formation assays were used to determine cell proliferation. Cell cycle and apoptosis were analyzed by flow cytometry. The relevant signaling pathways were evaluated by Western blot. The Log-Rank test and Kaplan-Meier were used to evaluate survival rate, and the Cox regression model was used to analyze multivariate analysis. Xenograft tumor mouse model was used for in vivo experiments.ResultsThe expression of GNA15 in adult AML was significantly higher than that in healthy individuals. Subjects with high GNA15 expression showed lower overall survival and relapse-free survival in adult AML with normal karyotype. High GNA15 expression was independently correlated with a worse prognosis in multivariate analysis. Knockdown of GNA15 inhibited cell proliferation and cell cycle progression, and induced cell apoptosis in AML cells. GNA15-knockdown induced down-regulation of p-P38 MAPK and its downstream p-MAPKAPK2 and p-CREB. Rescue assays confirmed that P38 MAPK signaling pathway was involved in the inhibition of proliferation mediated by GNA15 knockdown.ConclusionsIn summary, GNA15 was highly expressed in adult AML, and high GNA15 expression was independently correlated with a worse prognosis in adult AML with normal karyotype. Knockdown of GNA15 inhibited the proliferation of AML regulated by the P38 MAPK signaling pathway. Therefore, GNA15 may serve as a potential prognostic marker and a therapeutic target for AML in the future.

TBC1D16 predicts chemosensitivity and prognosis in adult acute myeloid leukemia (AML) patients

Acute myeloid leukemia (AML) is a hematopoietic disease with poor survival. Chemotherapy resistance is one of the determinant factors influencing AML prognosis. To identify genes possibly affecting the drug responses in AML, the Illumina Infinium MethylationEPIC (850K) was used to screen for differential DNA methylation loci between patients achieved complete remission (CR) or not (non-CR) after induction therapy in 37 AML patients. Then, 32 differentially methylated sites (DMS) were selected for replication in another 86 AML patients by next-generation sequencing. Nine sites including cg03988660, cg16804603, cg18166936, cg11308319, cg09095403, cg18493214, cg01443536, cg16030878 and cg10143426 were replicated. Analysis of the Gene Expression Omnibus (GEO) database showed that mRNA expression of TBC1D16 and HDAC4 was associated with AML prognosis. Methylation level of the cg16030878 in TBC1D16 3′-UTR correlated positively with TBC1D16 mRNA expression in samples both in the TCGA database and clinically collected in the study. Both higher cg16030878 methylation and higher TBC1D16 mRNA expression were associated with increased risk of non-CR and worse overall survival (OS) in AML patients. In AML cells, knockdown of TBC1D16 decreased cell proliferation and ERK phosphorylation levels, as well as increased sensitivity to mitoxantrone and decitabine indicated by IC50. In patients with combined use of decitabine, those patients with CR showed significantly lower TBC1D16 mRNA expression. On the contrary, knockdown of TBC1D16 resulted in decreased sensitivity to cytarabine in U937 cells. Our findings implicated that TBC1D16 is a potential predictor for chemosensitivity and prognosis in adult AML patients.

PCAT18, as a novel differentially regulated long noncoding RNA in adult acute myeloid leukemia patients revealed by next-generation sequencing.

Long noncoding RNAs (lncRNAs) play significant roles in the carcinogenesis and progression of human tumors. The aim of this work was to evaluate the expression level of lncRNAs in adult acute myeloid leukemia (AML) patients and to explore the function of candidate lncRNA PCAT18 in clinical diagnosis and prognosis of AML. Noncoding RNA screening was performed by second-generation sequencing on adult newly diagnosed AML patients and healthy controls. GO and KEGG pathway analysis were performed for functional analysis of differentially regulated lncRNAs. The expression of candidate lncRNA PCAT18 was detected by real-time PCR. In K-562 and THP-1 cells, proliferation, and cell cycle analysis were performed using CCK-8 assay and Cell Cycle Assay Kit. The lncRNA expression profile of AML patients and healthy controls showed that six upregulated (>5-fold) and eight downregulated (<0.2-fold) lncRNAs. The candidate lncRNA PCAT18 showed higher expression in AML patients with NPM1 mutation and favorable-risk. RT-PCR revealed a significant increase of PCAT18 expression comparing to control cells. PCAT18 overexpression obviously promoted cell proliferation and PCAT18 knockdown decreased cell proliferation. The fraction of the S phases was increased in the PCAT18 overexpression group and decreased in the PCAT18 knockdown group. The candidate lncRNA PCAT18 in our study was firstly found upregulated in AML samples, that its overexpression promoted cell proliferation and G1/S transition. Further study of PCAT18 and its target mRNAs are needed to confirm the mechanism of PCAT18 in AML. PCAT18 may act as diagnostic and prognosis biomarker for AML.

Core binding factor acute myeloid leukemia: Advances in the heterogeneity of KIT, FLT3, and RAS mutations (Review).

Core binding factor (CBF) is a heterodimer protein complex involved in the transcriptional regulation of normal hematopoietic process. In addition, CBF molecular aberrations represent approximately 20% of all adult Acute Myeloid Leukemia (AML) patients. Treated with standard therapy, adult CBF AML has higher complete remission (CR) rate, longer CR duration, and better prognosis than that of AML patients with normal karyotype or other chromosomal aberrations. Although the prognosis of CBF AML is better than other subtypes of adult AML, it is still a group of heterogeneous diseases, and the prognosis is often different. Recurrence and relapse-related death are the main challenges to be faced following treatment. Mounting research shows the gene heterogeneity of CBF AML. Therefore, to achieve an improved clinical outcome, the differences in clinical and genotypic characteristics should be taken into account in the evaluation and management of such patients, so as to further improve the risk stratification of prognosis and develop targeted therapy. The present article is a comprehensive review of the differences in some common mutant genes between two subtypes of CBF AML.

Clinical characteristics and prognostic study of adult acute myeloid leukemia patients with ASXL1 mutations

ABSTRACT Objectives: A total of 156 adult acute myeloid leukemia (AML) patients were enrolled in this study to explore the clinical characteristics and prognostic impact of ASXL1 mutations. Methods: Clinical characteristics, prognostic impact and the association between ASXL1 mutations and some other mutations were analyzed. Results: We found ASXL1 mutations were most frequently found in M5 subtype and intermediate risk karyotype and were correlated with TET2, DNMT3A and PHF6 mutations. A total of 145 patients were included in prognostic analysis; results showed ASXL1 mutations had no impact on OS and DFS. In normal karyotype-AML (CN-AML) and older (≥60 years) AML, ASXL1 mutations showed adverse impact on OS (P = 0.022; p = 0.019, respectively) and showed adverse prognostic tendency on DFS (p = 0.173; p = 0.108, respectively). ASXL1 mutations were also independent unfavourable prognostic factors for OS on CN-AML and older (≥60 years) AML patients and unfavourable factors for DFS on older (≥60 years) AML in multivariate analysis. Results also indicated that though ASXL1 mutations were associated with TET2, DNMT3A and PHF6 mutations, when coinciding with ASXL1 mutations, the prognosis of AML was not significantly impacted. Discussion: The reliability of our results need to be further confirmed by prospective randomized controlled studies covering a large numbers of AML patients. Conclusion: The results showed ASXL1 mutations may act as a poor prognostic index especially in elder AML and CN-AML patients.

Adult acute myeloid leukemia with TLS-ERG fusion gene positive: report of two cases and review of literature

Objective To investigate the clinical characteristics and prognosis of adult acute myeloid leukemia (AML) with TLS-ERG fusion gene positive. Methods Adult two AML patients with TLS-ERG fusion gene positive in the First Affiliated Hospital of Zhengzhou University in January 2017 and March 2018, respectively were enrolled, and their clinical characteristics and prognosis were analyzed. Results Both patients with TLS-ERG fusion gene positive were males. According to morphology classification, the first case was classified to AML-M5, and the other one was AML-M4. Both patients' immunophenotypic features showed CD56 expression, and CD25 was expressed in the first patient simultaneously. Both patients were treated with induction and consolidated intensive therapy based on Chinese guidelines for diagnosis and treatment of adult AML (not acute promyelocytic leukemia) and the guidelines for diagnosis and treatment of AML (relapse/refractory) in China. The first patient died 11 months after diagnosis, and the second patient remained in remission until the end of follow-up in February 2019 (12 months after diagnosis). Conclusion TLS-ERG fusion gene has low incidence rate, high recurrence rate, poor reinduction effect, poor prognosis and short survival time in adult AML. Key words: Leukemia, myeloid, acute; Translocation, genetic; TLS-ERG fusion gene

Influence of DNMT3A R882 mutations on AML prognosis determined by the allele ratio in Chinese patients

BackgroundThe influence of DNMT3A R882 mutations on adult acute myeloid leukemia (AML) prognosis is still controversial presently. The influence of R882 allele ratio on drug response and prognosis of AML is unknown yet. Besides, it is obscure whether anthracyclines are involved in chemoresistance resulted from R882 mutations.MethodsDNMT3A R882 mutations in 870 adult AML patients receiving standard induction therapy were detected by pyrosequencing. Associations of the mutants with responses to induction therapy and disease prognosis were analyzed.ResultsDNMT3A R882 mutations were detected in 74 (8.51%) patients and allele ratio of the mutations ranged from 6 to 50% in the cohort. After the first and second courses of induction therapy including aclarubicin, complete remission rates were significantly lower in carriers of the DNMT3A R882 mutants as compared with R882 wildtype patients (P = 0.022 and P = 0.038, respectively). Compared with R882 wild-type patients, those with the R882 mutations showed significantly shorter overall survival (OS) and disease-free survival (DFS) (P = 1.92 × 10−4 and P = 0.004, respectively). Patients with higher allele ratio of R882 mutations showed a significantly shorter OS as compared with the lower allele ratio group (P = 0.035).ConclusionOur results indicate that the impact of DNMT3A R882 mutations on AML prognosis was determined by the mutant-allele ratio and higher allele ratio could predict a worse prognosis, which might improve AML risk stratification. In addition, DNMT3A R882 mutations were associated with an inferior response to induction therapy with aclarubicin in Chinese AML patients.

Distinct prognostic values of Annexin family members expression in acute myeloid leukemia.

Annexin family consist of 12 members, many of them are frequently dysregulated in human cancers. However, the diagnosis and prognosis of Annexin family expression in acute myeloid leukemia (AML) remain elusive. The aim of the present study was to assess the prognostic value of Annexin expressions in adult and pediatric AML. GenomicScape tool was used to assess the prognostic value of the expressions of Annexin family members in a cohort of 162 adult AML patients. Quantitative reverse transcript real-time PCR (QRT-PCR) was performed to detect the ANXA2 expression level in the bone marrow-derived mononuclear cells (BMMCs) obtained from 101 pediatric AML patients and 30 controls. The results demonstrated that high mRNA expressions of ANXA2, ANXA6, and ANXA7 were significantly associated with worse prognosis, while ANXA5 was correlated with better prognosis in adult AML. QRT-PCR analysis showed that ANXA2 expression was dramatically downregulated in BMMCs of pediatric AML patients compared to controls (p < 0.0001). ROC analysis demonstrated that ANXA2 could efficiently differentiate pediatric AML patients from controls (AUC 0.872, p < 0.0001). Likewise, ANXA2 was significantly lower in AML patients with poor-risk karyotype (p = 0.048). Also, the level of ANXA2 trended to decrease in AML patients who had not achieving complete remission. Moreover, patients with lower expression of ANXA2 had higher death rate (p = 0.042) and shorter overall survival (HR 0.55, p = 0.042). Thus, these findings suggest that ANXA2 exerts poor prognostic effect on adult AML but favorable prognostic effect on pediatric AML. Collectively, Annexin family members exert distinct prognostic roles in AML, and ANXA2 can be used as a biological marker for diagnosis and prognosis of pediatric AML.

1,123 Consecutive Adults with Non-APL Acute Myeloid Leukemia: The Mayo Clinic Experience

Background:Pre-treatment determinants of survival in adult acute myeloid leukemia (AML) include performance status, age, karyotype, the distinction between primary and non-primary AML and FLT3-ITD/NPM1 mutational status. Current literature on AML natural history and risk factors is often based on information derived from stringent protocol studies. In the current series of 1,123 adult patients seen at the Mayo Clinic between 2004 and 2017, we examined long-term survival specified by a number of primarily established risk factors.Methods:Diagnosis of AML and its sub-classification was according to World Health Organization criteria. Study subjects were recruited from the Mayo Clinic AML database. Conventional response criteria were used for CR and CRi assignment; the latter met all criteria for CR with the exception of platelet count <100 x 109/l or absolute neutrophil cunt <1 x 109/l. Standard statistical methods were used for analysis of overall survival, calculated from the initial diagnosis of AML to date of death or last follow-up; analyses were performed both in the absence and in the presence of censoring of survival at time of allogenic stem cell transplant (ASCT). The JMP® Pro 13.0.0 software from SAS Institute, Cary, NC, USA, was used for all calculations.Results:1,123 adult patients (median age 65 years, range 18-94; 61% males) with non-APL AML were considered; 61% were age >60 years. 351 (31%) patients were seen between 2004 and 2009 and 772 (69%) between 2010 and 2017. AML subcategories were primary (56%), post-myelodysplastic syndromes (post-MDS; 24%), therapy-related (10%), post-myeloproliferative neoplasm (post-MPN; 8%) and post-MDS/MPN (3%). Cytogenetic risk distribution, according to the European LeukemiaNet classification, was favorable in 47 (4%), intermediate in 650 (58%) and adverse risk in 426 (38%) patients. FLT3, NPM1 and CEBPA mutation information was available in 462 (24% mutated), 393 (27% mutated) and 228 (11% mutated) patients, respectively.Treatment included intensive chemotherapy (IC) in 766 (68%) patients, less aggressive chemotherapy, including the use of hypomethylating agents in 144 (13%) and supportive care alone in 213 (19%) patients. ASCT was utilized in 258 (23%) cases, almost all performed after achieving CR/CRi. Complete remission (CR) and CR with incomplete count recovery (CRi) were listed in 333 (30%) and 248 (22%) patients, respectively; the corresponding rates in IC-treated patients were 43% and 32%. Almost all cases of CR/CRi occurred in IC-treated patients; 2 (1.4%) CRs were listed for less aggressive chemotherapy.After a median follow-up of 11 months, 798 (71%) deaths were recorded. Median survival for all 1,123 patients was 14 months with 1-, 3- and 5-year survival rates of 54%, 29% and 23%, respectively; a slight but significant (p=0.01) improvement in survival was apparent in more recent years (Figure 1a). Figures 1b, 1c and 1d depict analysis stratified by AML subcategories, treatment received and response obtained, respectively. Similarly, figures 2a, 2b and 2c depict analysis stratified by karyotype, use of ASCT and age.Multivariable analysis of pre-treatment parameters evaluable in all 1,123 patients identified age >60 years (HR 2.2, 1.9-2.6), adverse karyotype (HR 2.9, 1.9-4.9), intermediate-risk karyotype (HR 1.6, 1.02-2.6), post-MPN AML (HR 1.9, 1.5-2.4) and other secondary AML (HR 1.3 (1.1-1.6), as risk factors for shortened survival; the inclusion in the model of FLT3/NPM1 mutational status in 392 informative cases confirmed the adverse prognostic effect of age >60 years (HR 1.8, 1.4-2.5), adverse karyotype (HR 3.7, 1.4-15.3), post-MPN AML (HR 2.8, 1.6-4.6), other secondary AML (HR 1.4, 1.0-1.9) and FLT3+NPM1- (HR 2.8, 1.6-4.9) and FLT3-NPM1- (HR 1.7, 1.2-2.7) profile. Results were unchanged when survival was censored at time of ASCT. Additional prognostic interaction with treatment strategy and ASCT is further elaborated in an accompanying abstract to be presented.Conclusions:The current study, the largest coming from a single institution, provides practically useful information that should assist with patient consultation on AML prognosis and treatment. The study confirms the primary prognostic importance of age, karyotype and FLT3/NPM1 mutational status, in real-life practice. Novel observations included comparable value of CRi vs CR and the particularly worse prognosis associated with post-MPN AML. [Display omitted] DisclosuresAl-Kali:Novartis: Research Funding.

Transposable Element Expression in Acute Myeloid Leukemia Transcriptome and Prognosis

Over half of the human genome is comprised of transposable elements (TE). Despite large-scale studies of the transcriptome in cancer, a comprehensive look at TE expression and its relationship to various mutations or prognosis has not been performed. We characterized the expression of TE in 178 adult acute myeloid leukemia (AML) patients using transcriptome data from The Cancer Genome Atlas. We characterized mutation specific dysregulation of TE expression using a multivariate linear model. We identified distinct patterns of TE expression associated with specific mutations and transcriptional networks. Genes regulating methylation was not associated with significant change in TE expression. Using an unpenalized cox regression analysis we identified a TE expression signature that predicted prognosis in AML. We identified 14 candidate prognostic TE transcripts (TEP) that classified AML as high/low-risk and this was independent of mutation-based and coding-gene expression based risk-stratification. TEP was able to predict prognosis in independent cohorts of 284 pediatric AML patients and 19 relapsed adult AML patients. This first comprehensive study of TE expression in AML demonstrates that TE expression can serve as a biomarker for prognosis in AML, and provides novel insights into the biology of AML. Studies characterizing its role in other cancers are warranted.

Increase in myeloid-derived suppressor cells (MDSCs) associated with minimal residual disease (MRD) detection in adult acute myeloid leukemia.

Myeloid-derived suppressor cells (MDSCs) are thought to help provide a cellular microenvironments in many solid tumors, in which transformed cells proliferate, acquire new mutations, and evade host immunosurveillance. In the present study, we found that MDSCs (CD33 + CD11b + HLA-DR(low/neg)) in bone marrow were significantly increased in adult acute myeloid leukemia (AML) patients. MDSCs levels in newly diagnosed AML patients correlated well with extramedullary infiltration and plasma D-dimer levels. Remission rates in the MDSCs > 1500 group and MDSCs < 1500 group were 72.73 and 81.25 %, respectively. No significant differences were found between the two groups. MDSC levels in the complete remission group were significantly decreased after chemotherapy, while in the partial remission and non-remission groups, there were no significant differences. The level of MDSCs in the high minimal residual disease (MRD) group was significantly higher than that in the middle and low MRD groups. High levels of Wilms' Tumor-1 (WT-1) protein were strongly correlated with higher bone marrow MDSC levels. In conclusion, we report here a population of immunosuppressive monocytes in the bone marrow of patients with AML characterized by the CD33(high)CD11b + HLA-DR(low/neg) phenotype. These cells appear to impact the clinical course and prognosis of AML. This data may provide potentially important targets for novel therapies.

Hierarchy in gene expression is predictive of risk, progression, and outcome in adult acute myeloid leukemia

Cancer progresses with a change in the structure of the gene network in normal cells. We define a measure of organizational hierarchy in gene networks of affected cells in adult acute myeloid leukemia (AML) patients. With a retrospective cohort analysis based on the gene expression profiles of 116 AML patients, we find that the likelihood of future cancer relapse and the level of clinical risk are directly correlated with the level of organization in the cancer related gene network. We also explore the variation of the level of organization in the gene network with cancer progression. We find that this variation is non-monotonic, which implies the fitness landscape in the evolution of AML cancer cells is non-trivial. We further find that the hierarchy in gene expression at the time of diagnosis may be a useful biomarker in AML prognosis.

Activated Fibroblasts Protect Acute Myeloid Leukemia Cells from Chemotherapy

Introduction: It has become clear that cancer is not only just a disease of the genes, but the tumor microenvironment (TME) plays an important role in cancer progression (Borriello L & DeClerck YA, 2014). In leukemia, the bone marrow plays a special role in environment-mediated drug resistance as it is not only a sanctuary protecting tumor cells from cytotoxic drugs, but also a source of many stromal cells that colonize primary tumors and contribute to the pre-metastatic niche (Borriello L & DeClerck YA, 2014; Meads MB, et al, 2008). As we all know, there exists two distinct BM niches in this significant microenvironment: ‘osteoblastic (endosteal)’ and ‘vascular’ niches (Tabe Y & Konopleva M, 2014; Konopleva M, et al, 2009). Besides these two, scholars transferred to focus on the stromal in bone marrow，which may have importance effects on leukemic cells (Wu S, et al, 2005; Campana D, et al, 2005). Shriram V. Nath et al. found that there was a negative correlation between reticulin fiber density (RFD) at diagnosis in childhood ALL and white blood cell count in peripheral blood. Similarly, there was a negative correlation between RFD and the percentage of blast cells in blood. They speculated fiber in the bone marrow leading to poor prognosis in acute lymphoblastic leukemia (ALL) via anchoring leukemia cells in bone marrow stromal (Nath SV, et al. 2011). But the role of fibers and its mainly producing cells fibroblasts has not been previously studied in acute myeloid leukemia (AML). Therefore, we retrospectively investigate the bone marrow biopsies of primary AML patients, to analyze the relationship between the RFD and prognosis in adult AML, and to identify and quantitative analyze protective effects of the fibroblasts on leukemia cells from chemotherapy in vitro.Methods: Makers of activated fibroblasts were stained by immunohistochemistry on bone marrow biopsies; The RFD were evaluated based on the grid point method of computer; Obtained activated fibroblasts by induced BM-MSC of primary AML with human recombinant TGFβ1.(4) Analyzed protective effects of activated fibroblasts by co-cultured with leukemia cells such as THP-1/K562, futher explored the mechanism via SB431542, a specific inhibitor of TGFβ signaling pathway.Result:RFD in primary AML was significant higher than control. Patients with higher RFD indicated poorer prognosis; However, collagenI coated plates showed no effects on survival rate of the leukemic cells. Here, we demonstrated that the general makers of activated fibroblasts: FSP1, α-SMA and FAP in primary AML were significant higher than control, implied that there existed amount of activated fibroblasts in patients; Activated fibroblast protect both THP-1 and K562 from apoptosis with treatment of Ara-c, and arrested them in phase of G0/G1. Moreover, this protect effects of activated fibroblast will be cancelled with SB431542.Conclusion:Activated fibroblasts and fibrous tissue were both proliferated abnormally in primary AML, and the later was significantly associated with relapse-free survival and overall survival of patients, indicating that RFD could be used as an important factor of poor prognosis and should guide clinical intervention. In vitro induced activated fibroblasts could be able to protect leukemia cells from chemotherapy. The possible mechanisms might be that the soluble cytokines TGFβ1, but not collagen I, which were secreted by activated fibroblasts, contributed to leukemia protection. In addition to this, activated fibroblasts could also change cell cycle of tumor cells, make them more arrested in G0/G1 phase, thus decreased the their chemotherapy sensitivity. DisclosuresNo relevant conflicts of interest to declare.

Advances of MicroRNA in Adult Acute Myeloid Leukemia

MicroRNA (miRNA) is a noncoding single strand RNA that regulates mRNA and protein expression of target genes at post-transcriptional level.Characteristic expression of miRNA has been demonstrated to play an essential role in the occurrence and development of adult acute myeloid leukemia (AML),associated with its morphologic subtypes,cytogenetics and molecular biological features,and clinical prognosis.Taking deep insights into the miRNA expression profiles in AML,will provide new theoretical basis and application solutions for the diagnosis,treatment and prognosis of adult AML. Key words: MicroRNAs; Leukemia,myeloid,acute; Adult; Cytogenetics; Molecular biology; Prognosis

Research advances of IDH gene mutation and AML

The isocitrate dehydrogenase (IDH) gene mutation has been recently found, which may be involved in the occurrence of leukemia. The incidence of IDH gene mutation in the patients with adult acute myeloid leukemia (AML) is high, especially in the AML patients with normal karyotype. Different subtype and molecular biology of IDH display a different effect on the AML prognosis. This gene mutation is related with treatment response, residual, recurrence of leukemia, and it could be a sign of test and a monitoring tool of minimal residual disease (MRD). The IDH gene mutation may be an index for predicting prognosis and guiding therapy. In this article, the research progress of IDH gene mutation and its correlation with acute myeloid leukemia, especially with the clinical characteristics,are reviewed.

Low Frequency and Poor Prognosis Of MLL-Partial Tandem Duplications In Pediatric Acute Myeloid Leukemia Using MLPA Method: The Japanese Pediatric Leukemia/Lymphoma Study Group (JPLSG) AML-05 Trial

BackgroundMixed-lineage leukemia (MLL)-partial tandem duplications (PTDs) are found in 3-5% of adult acute myeloid leukemia (AML), and are associated with poor prognosis. Report of the incidence and prognostic relevance of MLL-PTD in pediatric AML is limited and large differences in the frequency have been reported. In pediatric AML cases, a frequency of 10-13% for MLL-PTD was detected using mRNA RT-PCR, whereas a frequency of only 2.5% was detected using multiplex ligation-dependent probe amplification (MLPA). We studied the frequency and prognostic effect of MLL-PTD in pediatric patients with AML treated with JPLSG AML-05 trial (between 2006-2010). MethodsMLL-PTD of 331 pediatric de novo AML in the AML-05 trial was analyzed from genomic DNA extracted from their diagnostic bone marrow samples using MLPA analysis. We designed a probe mix for MLPA analysis containing adjacent probes within exon 2-5 and exon 7-13 of the MLL gene for the detection of common and rare type MLL-PTD. Exon 17 of the MLL gene was used as an internal control. We also performed RT-PCR to detect MLL-PTD transcripts to allow comparison with the MLPA results. To assess whether MLL-PTD overlap with known gene abnormalities, such as FLT3, KIT, and NPM1 mutations, mutational analyses of these genes were also performed in patients in the AML-05 trial. ResultsMLL-PTD was detected in 9 (2.7%) of 331 patients by MLPA analysis. In 303/331 samples mRNA RT-PCR screening for MLL-PTD was performed, and MLL-PTD was detected in 38 (12.5%). In 9 cases, both MLPA and mRNA-RT-PCR were positive for MLL-PTD. The characteristics of the 9 patients with MLL-PTD using MLPA analysis were below. None of the patients harbouring an MLL-rearrangement, t(8;21) or inv(16) revealed a MLL-PTD. All MLL-PTD cases were found in patients with normal cytogenetics. FLT3-ITD was present in 4 of 9 patients with MLL-PTD, while none of KIT and NPM1 mutation was detected in MLL-PTD cases. There was a significantly higher frequency of FLT3-ITD in patients with an MLL-PTD than in those without MLL-PTD (p=0.016). Among these 9 patients, 5 patients were classified as FAB-M5a (p=0.0068), and other 4 patients were classified as FAB-M1, M2, M4 and M6a. The age of patients with MLL-PTD was higher than that of patients without MLL-PTD (median 11.8 years (range; 9-15) and 7.4 years (range; 0-17), respectively; p=0.004). Patients with MLL-PTD tend to have higher white blood cell counts (WBC) at initial diagnosis than those without MLL-PTD (median WBC 6.0×10*9/l (range; 1500-151000) versus 2.2×10*9/l (range; 617-985000a) respectively; p=0.18). All 9 patients with MLL-PTD had events. There was a significantly higher frequency of event including refractory disease, relapse and death in patients with an MLL-PTD than in those without MLL-PTD (p=0.001). Only one of 9 patients was achieved complete remission (CR) after induction therapy (p= 1.1×10-11). Six of 9 patients relapsed, and 5 patients died. ConclusionUsing DNA-MLPA as a novel screenings technique, low frequency of MLL-PTD in pediatric AML was found. However, MLL-PTD is highly associated with a poor prognosis in pediatric AML. These data suggest that screening for MLL-PTD in pediatric patients with AML is critical not only for outcome prediction but also for risk-adapted therapy. Disclosures:No relevant conflicts of interest to declare.