Search

Background: CD300s are a group of proteins playing vital roles in immune responses. However, much is yet to be elucidated regarding the expression patterns and clinical significances of CD300s in cancers. Methods: In this study, we comprehensively investigated CD300s in a pan‐cancer manner using multi‐omic data from The Cancer Genome Atlas. We also studied the relationship between CD300s and the immune landscape of AML. Results: We found that CD300A‐CD300LF were generally overexpressed in tumors (especially AML), whereas CD300LG was more often downregulated. In AML, transactivation of CD300A was not mediated by genetic alterations but by histone modification. Survival analyses revealed that high CD300A‐CD300LF expression predicted poor outcome in AML patients; the prognostic value of CD300A was validated in seven independent datasets and a meta dataset including 1115 AML patients. Furthermore, we demonstrated that CD300A expression could add prognostic value in refining existing risk models in AML. Importantly, CD300A‐CD300LF expression was closely associated with T‐cell dysfunction score and could predict response to AML immunotherapy. Also, CD300A was found to be positively associated with HLA genes and critical immune checkpoints in AML, such as VISTA, CD86, CD200R1, Tim‐3, and the LILRB family genes. Conclusions: Our study demonstrated CD300s as potential prognostic biomarker and an ideal immunotherapy target in AML, which warrants future functional and clinical studies. [ABSTRACT FROM AUTHOR]

Acute myeloid leukemia (AML) is the most common type of hematological malignancy. Recently, an increasing number of reports have shown that many circular RNAs can act as effective targets for AML. However, the roles of circ_0059707 in AML remain largely unclear. In this study, we found that the expression levels of circ_0059707 were significantly decreased in AML patients with respect to normal controls (p < 0.001). Low expression levels of circ_0059707 were also associated with a poor prognosis. Furthermore, circ_0059707 overexpression inhibited cell growth and promoted apoptosis in leukemia cells, compared with control cells. Circ_0059707- and empty plasmid-transfected cells were injected subcutaneously into BALB/c nude mice. We found that the tumor volume was significantly lower in mice in the circ_0059707 group than in control mice (p < 0.01). Nuclear pyknosis, nuclear fragmentation, nuclear dissolution, and cell necrosis were observed in the circ_0059707 group by HE staining. CircInteractome analysis showed that 25 microRNAs (miRNAs), including miR-1287-5p, ©-miR-1825, a©hsa-miR-326, may be potential targets for circ_0059707. The expression of these miRNAs was analyzed in both the GEO GSE51908 and the GSE142700 databases. miR-1287-5p expression was lower in AML patients compared with controls in both the GSE51908 and the GSE142700 datasets. Moreover, we demonstrated that miR-1287-5p expression was down-regulated in AML patients and up-regulated in circ_0059707-overexpressing cells. Collectively, our research demonstrated that the down-regulation of circ_0059707 was highly evident in de novo AML patients. Our analysis also demonstrated that circ_0059707 inhibited cell growth and promoted apoptosis by up-regulating miR-1287-5p. [ABSTRACT FROM AUTHOR]

The role of B7‐H3 in acute myeloid leukemia (AML) is not fully understood. Two previous studies investigating its expression and significances in AML are partially different. In this study, we aimed to systematically characterize the genomic and immune landscape in AML patients with altered B7‐H3 expression using multi‐omics data in the public domain. We found significantly increased B7‐H3 expression in AML compared to either other hematological malignancies or healthy controls. Clinically, high B7‐H3 expression was associated with old age, TP53 mutations, wild‐type WT1 and CEBPA, and the M3 and M5 FAB subtypes. Moreover, we observed that increased B7‐H3 expression correlated significantly with a poor outcome of AML patients in four independent datasets. Gene set enrichment analysis (GSEA) revealed the enrichment of the "EMT" oncogenic gene signatures in high B7‐H3 expressers. Further investigation suggested that B7‐H3 was more likely to be associated with immune‐suppressive cells (macrophages, neutrophils, dendritic cells, and Th17 cells). B7‐H3 was also positively associated with a number of checkpoint genes, such as VISTA (B7‐H5), CD80 (B7‐1), CD86 (B7‐2), and CD70. In summary, we uncovered distinct genomic and immunologic features associated with B7‐H3 expression in AML. This may lead to a better understanding of the molecular mechanisms underlying B7‐H3 dysregulation in AML and to the development of novel therapeutic strategies. [ABSTRACT FROM AUTHOR]

Acute myeloid leukemia (AML) is a heterogeneous disease related to a broad spectrum of molecular alterations. The successes of immunotherapies treating solid tumors and a deeper understanding of the immune systems of patients with hematologic malignancies have promoted the development of immunotherapies for the treatment of AML. And high tumor mutational burden (TMB) is an emerging predictive biomarker for response to immunotherapy. However, the association of gene mutation in AML with TMB and immunological features still has not been clearly elucidated. In our study, based on The Cancer Genome Atlas (TCGA) and BeatAML cohorts, 20 frequently mutated genes were found to be covered by both datasets in AML. And TP53 mutation was associated with a poor prognosis, and its mutation displayed exclusiveness with other common mutated genes in both datasets. Moreover, TP53 mutation correlated with TMB and the immune microenvironment. Gene Set Enrichment Analysis (GSEA) showed that TP53 mutation upregulated signaling pathways involved in the immune system. In summary, TP53 mutation is frequently mutated in AML, and its mutation is associated with dismal outcome, TMB, and immunological features, which may serve as a biomarker to predict immune response in AML. [ABSTRACT FROM AUTHOR]

It was previously reported that PRR34‐AS1 was overexpressed in some solid tumors. PRR34‐AS1 promoter was shown to have a differential methylation region (DMR), and was hypomethylated in acute myeloid leukemia (AML). Therefore, the present study used real‐time quantitative PCR (RQ‐PCR) to explore the expression characteristics of PRR34‐AS1 in AML. In addition, the correlation between the expression of PRR34‐AS1 and clinical prognosis of AML was determined. The findings of this study indicated that high PRR34‐AS1 expression was bound up with shorter overall survival (OS) in AML patients (p = 0.002). Moreover, patients with high expression of PRR34‐AS1 had significantly lower complete remission (CR) rate compared with those with low expression of PRR34‐AS1 after induction chemotherapy. Furthermore, multivariate analysis confirmed that PRR34‐AS1 expression was an independent factor affecting CR in whole‐AML, non‐APL‐AML, and CN‐AML patients (p = 0.032, 0.039, and 0.036, respectively). Methylation‐specific PCR (MSP) and bisulfite sequencing PCR (BSP) were used to explore the methylation status of PRR34‐AS1. PRR34‐AS1 promoter showed a pattern of hypomethylation in AML patients compared with normal controls (p = 0.122). Notably, of whole‐AML and non‐APL‐AML patients, PRR34‐AS1 hypomethylated patients presented a significantly shorter OS than those with a hypermethylated PRR34‐AS1 (p = 0.010 and 0.037, respectively). Multivariate analysis confirmed that the hypomethylation of PRR34‐AS1 served as an independent prognostic indicator in both whole‐cohort AML and non‐APL‐AML categories (p = 0.057 and 0.018, respectively). In summary, the findings of this study showed that abnormalities in PRR34‐AS1 are associated with poor prognosis in AML. Therefore, monitoring this index may be important in the prognosis of AML and can provide information on effective chemotherapy against the disease. [ABSTRACT FROM AUTHOR]

Background: Obesity confers enhanced risk for multiple diseases including cancer. The DNA methylation alterations in obesity-related genes have been implicated in several human solid tumors. However, the underlying role and clinical implication of DNA methylation of obesity-related genes in acute myeloid leukemia (AML) has yet to be elucidated. Results: In the discovery stage, we identified that DNA methylation-associated LEP expression was correlated with prognosis among obesity-related genes from the databases of The Cancer Genome Atlas. In the validation stage, we verified that LEP hypermethylation was a frequent event in AML by both targeted bisulfite sequencing and real-time quantitative methylation-specific PCR. Moreover, LEP hypermethylation, correlated with reduced LEP expression, was found to be associated with higher bone marrow blasts, lower platelets, and lower complete remission (CR) rate in AML. Importantly, survival analysis showed that LEP hypermethylation was significantly associated with shorter overall survival (OS) in AML. Moreover, multivariate analysis disclosed that LEP hypermethylation was an independent risk factor affecting CR and OS among non-M3 AML. By clinical and bioinformatics analysis, LEP may be also regulated by miR-517a/b expression in AML. Conclusions: Our findings indicated that the obesity-related gene LEP methylation is associated with LEP inactivation, and acts as an independent prognostic predictor in AML. [ABSTRACT FROM AUTHOR]

The deregulated DLX gene family members DLX1/2/3/4/5/6 (DLXs) caused by DNA methylation has been demonstrated in various cancers with therapeutic target value. However, the potential role of DLXs methylation in myeloid neoplasms such as acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) remains to be elucidated. Clinical significance of DLXs methylation/expression was analyzed in patient with AML and MDS. The functional roles of DLXs were determined in vitro. In the identification stage, we found that lower DLX5 expression was correlated with prognosis in AML among all DLXs analyzed by The Cancer Genome Atlas datasets. In the validation stage, we revealed that reduced DLX5 expression was frequently occurred, and was also correlated with promoter hypermethylation in AML evaluated by targeted bisulfite sequencing. Epigenetic studies also showed that DLX5 promoter DNA methylation was associated with its expression. By quantitative polymerase chain reaction, we also validated that DLX5 hypermethylation was frequent event in both AML and MDS, and also correlated with MDS transformation to leukemia. Moreover, DLX5 hypermethylation was associated with lower rate of complete remission and shorter time of leukemia‐free/overall survival, and was also confirmed by Logistic/Cox regression analysis. Functional studies revealed the antiproliferative and pro‐apoptotic effects of DLX5 in MDS‐derived AML cell‐line SKM‐1. Finally, bioinformatics analysis demonstrated that DLX5 functioned in leukemogenesis may be through the association with PI3K/Akt signaling pathway. Collectively, our findings demonstrated that DLX5 methylation, negatively correlated DLX5 expression, was a potential prognostic and predictive indicator in patients with AML and MDS, which could also act as an epigenetic driver in myeloid neoplasms. [ABSTRACT FROM AUTHOR]

Hematological malignancies possess a distinctive immunologic microenvironment compared with solid tumors. Here, using an established computational algorithm (CIBERSORT), we systematically analyzed the overall distribution of 22 tumor-infiltrating leukocyte (TIL) populations in more than 2000 bone marrow (BM) samples from 5 major hematological malignancies and healthy controls. Focusing on significantly altered TILs in acute myeloid leukemia (AML), we found that patients with AML exhibited increased frequencies of M2 macrophages, compared to either healthy controls or the other four malignancies. High infiltration of M2 macrophages was associated with poor outcome in AML. Further analysis revealed that CD206, a M2 marker gene, could faithfully reflect variation in M2 fractions and was more highly expressed in AML than normal controls. High CD206 expression predicted inferior overall survival (OS) and event-free survival (EFS) in two independent AML cohorts. Among 175 patients with intermediate-risk cytogenetics, the survival still differed greatly between low and high CD206 expressers (OS; P <.0001; 3-year rates, 56% v 32%; EFS; P <.001; 3-year rates, 47% v 25%). When analyzed in a meta-analysis, CD206 as a continuous variable showed superior predictive performance than classical prognosticators in AML (BAALC, ERG, EVI1, MN1, and WT1). In summary, M2 macrophages are preferentially enriched in AML. The M2 marker CD206 may serve as a new prognostic marker in AML. [ABSTRACT FROM AUTHOR]

Background: Downstream of tyrosine kinase 6 (DOK6), which is specifically expressed in the nervous system, was previously recognized as an adapter only in neurite outgrowth. Recent studies also demonstrated the potential role of DOK6 in solid tumors such as gastric cancer and breast cancer. However, previous studies of DOK6 have not dealt with its roles in myeloid malignancies. Herein, we verified the promoter methylation status of DOK6 and further explored its clinical implication in de novo acute myeloid leukemia (AML). Methods: A total of 100 newly diagnosed adult AML patients were involved in the current study. DOK6 expression and methylation were detected by real‐time qPCR and methylation‐specific PCR (MSP), respectively. Bisulfite sequencing PCR (BSP) was performed to assess the methylation density of the DOK6 promoter. Results: Downstream of tyrosine kinase 6 promoter methylation was significantly increased in AML patients compared to controls (P = .037), whereas DOK6 expression significantly decreased in AML patients (P < .001). The expression of DOK6 was markedly up‐regulated after treated by 5‐aza‐2′‐deoxycytidine (5‐aza‐dC) in THP‐1 cell lines. The methylation status of the DOK6 promoter was associated with French‐American‐British classifications (P = .037). There was no significant correlation existed between DOK6 expression and its promoter methylation (R = .077, P = .635). Interestingly, of whole‐AML and non‐APL AML patients, both have a tendency pertaining to the DOK6 methylation group and a significantly longer overall survival (OS) than the DOK6 unmethylation group (P = .042 and.036, respectively). Conclusion: Our study suggested that DOK6 promoter hypermethylation was a common molecular event in de novo AML patients. Remarkably, DOK6 promoter methylation could serve as an independent and integrated prognostic biomarker not only in non‐APL AML patients but also in AML patients who are less than 60 years old. [ABSTRACT FROM AUTHOR]

Background: BCL2 protein inhibitor venetoclax (ABT-199) has been authorized by Food and Drug Administration for relapsed/refractory chronic lymphoid leukemia with 17p deletion. Although venetoclax/ABT-199 also caused cell death in acute myeloid leukemia (AML), whether it could be applied to clinical treatment needs further studies. Here, we revealed clinical implication of BCL2 overexpression in de novo adult AML, and may provide theoretical basis for targeted therapy using venetoclax. Methods: BCL2 expression was analyzed in adult AML patients from public datasets The Cancer Genome Atlas (TCGA) and confirmed by another independent cohort from our own data. Results: BCL2 expression showed up-regulated in AML patients among TCGA data and confirmed by our own data. BCL2 overexpression was correlated with FAB-M0/M1, whereas BCL2 under-expression was related to FAB-M5. However, BCL2 expression has no effect on overall survival (OS) and leukemia-free survival (LFS) of AML patients (determined in BCL2low and BCL2high groups). Interestingly, in the BCL2low group, patients undergoing autologous or allogeneic hematopoietic stem cell transplantation (auto/allo-HSCT) had significantly better OS and LFS compared with patients only received chemotherapy, whereas, no significant difference was found in OS and LFS between chemotherapy and auto/allo-HSCT patients in the BCL2high group. BCL2 expression was found positively correlated with HOX family gene, and negatively correlated with tumor suppressor microRNA such as miR-195, miR-497, and miR-193b. Conclusions: BCL2 overexpression identified specific FAB subtypes of AML, but it did not affect prognosis. Patients with BCL2 overexpression did not benefit from auto/allo-HSCT among whole-cohort-AML and cytogenetically normal AML. [ABSTRACT FROM AUTHOR]

The current study was aimed to investigate integrin beta‐like 1 (ITGBL1) methylation pattern and its clinical relevance in patients with acute myeloid leukemia (AML). Real‐time methylation‐specific polymerase chain reaction (PCR; RQ‐MSP) and bisulfite sequencing PCR (BSP) were performed to detect the methylation of ITGBL1 promoter. Real‐time quantitative PCR (RT‐qPCR) was performed to analyze ITGBL1 transcript level. The results showed that ITGBL1 methylation level in 131 patients with AML was significantly higher than 29 controls (p < 0.001). The ITGBL1‐hypermethylated group tended to have a higher bone marrow (BM) blasts (p = 0.076). Meanwhile, ITGBL1‐hypermethylated patients tended to have a lower complete remission (CR) rate (p = 0.102). ITGBL1‐hypermethylated patients had significantly shorter overall survival (OS) and leukemia‐free survival (LFS) than ITGBL1 hypomethylated patients in whole AML cohort (p = 0.009 and 0.043, respectively) and patients with nonacute promyelocytic leukemia (APL ; p = 0.023 and 0.039, respectively). Multivariate analysis confirmed that the ITGBL1 methylation served as an independent prognostic factor in both patients with whole‐cohort AML (p = 0.030) and patients with non‐APL (p = 0.020). Furthermore, the ITGBL1 methylation level was significantly decreased in follow‐up AML patients who achieved complete remission after induction therapy (P = 0.001). ITGBL1 methylation negatively correlated with ITGBL1 expression in patients with AML (R = −0.328, p = 0.008). Moreover, demethylation of ITGBL1 could increase the ITGBL1 expression in the K562 leukemic cell line (p < 0.05). In conclusion, the ITGBL1 hypermethylation is a potential biomarker for predicting prognosis and monitoring disease status in patients with AML. The results showed that ITGBL1 methylation level in patients with AML was significantly higher than controls. ITGBL1‐hypermethylated patients had significantly shorter overall survival (OS) and leukemia‐free survival (LFS) than ITGBL1 hypomethylated patients in patients with whole AML cohort and nonacute promyelocytic leukemia (APL). Multivariate analysis confirmed that ITGBL1 methylation served as an independent prognostic factor in both patients with whole‐cohort AML and patients with non‐APL. [ABSTRACT FROM AUTHOR]

The clinical activity of decitabine (5‐aza‐2‐deoxycytidine, DAC), a hypomethylating agent, has been demonstrated in acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) patients. However, secondary resistance to this agent often occurs during treatment and leads to treatment failure. It is important to clarify the mechanisms underlying the resistance for improving the efficacy. In this study, by gradually increasing concentration after a continuous induction of DAC, we established the DAC‐resistant K562 cell line (K562/DAC) from its parental cell line K562. The proliferation and survival rate of K562/DAC was significantly increased, whereas the apoptosis rate was remarkably decreased than that of K562 after DAC treatment. In K562/DAC, a total of 108 genes were upregulated and 118 genes were downregulated by RNA‐Seq. In addition, we also observed aberrant expression of DDX43/H19/miR‐186 axis (increased DDX43/H19 and decreased miR‐186) in K562/DAC cells. Ectopic expression of DDX43 in parental K562 cells rendered cells resistant to the DAC. Taken together, we successfully established DAC‐resistant K562 cell line which can serve as a good model for investigating DAC resistance mechanisms, and DDX43/H19/miR‐186 may be involved in DAC resistance in K562. [ABSTRACT FROM AUTHOR]

Background:  Altered expression of the BCL-2 family member MCL-1 has been linked to the progression and outcome of various malignancies. Recently, MCL-1 inhibitor S63845 was reported to kill MCL-1-dependent cancer cells and has potential value in clinical application. Purpose: Herein, we reported MCL-1 expression pattern in Chinese de novo acute myeloid leukemia (AML) and its impact on prognosis and may provide theoretical basis for AML patients using MCL-1 inhibitor in clinics. Real-time quantitative PCR was carried out to detect the transcript of MCL-1 in AML patients. Results: MCL-1 expression was significantly up-regulated in AML compared with controls (P=0.042). We divided the patients into two groups (higher and lower expression of MCL-1) based on the median level. Among both non-acute promyelocytic leukemia (APL) and cytogenetically normal AML (CN-AML), patients with higher expression of MCL-1 correlated with lower complete remission (CR) rate (P=0.031 and 0.004, respectively) and shorter overall survival (OS) time (P=0.008 and 0.004, respectively) compared with those with lower expression of MCL-1. Meanwhile, Cox regression analyses revealed that overexpression of MCL-1 acted as an independent risk factor for OS in non-APL patients and CN-AML patients (P=0.011 and 0.045, respectively). In follow-up patients, MCL-1 expression level decreased after CR compared with newly diagnosis time (P=0.020) and increased after relapse (P=0.004). Conclusion: Our findings suggest that higher expression of MCL-1 predicts poor prognosis and can be used for disease monitoring. [ABSTRACT FROM AUTHOR]

Previous studies have been indicated that integrin α2 (ITGA2) may be important in cell migration, invasion, survival, and angiogenesis. However, the correlation between ITGA2 expression and acute myeloid leukemia (AML) is still unclear. Real‐time quantitative polymerase chain reaction was carried out to analyze ITGA2 messenger RNA level. Methylation‐specific polymerase chain reaction (PCR) and bisulfite sequencing PCR were performed to detect the methylation of ITGA2 promoter. ITGA2 expression was significantly upregulated in 134 de novo AML patients compared with 33 controls (p = 0.007). ITGA2high group had markedly lower complete remission (CR) rate than ITGA2low group (p = 0.011). Furthermore, the overall survival in ITGA2high patients was significantly shorter than ITGA2low patients throughout AML cohort, non–acute promyelocytic leukemia (APL) and cytogenetic normal‐AML (p = 0.001, 0.002, and 0.044, respectively). Multivariate analysis confirmed that ITGA2 overexpression served as an independent prognostic factor in both whole‐cohort AML patients (p = 0.018) and non‐APL AML patients (p = 0.021). Besides, ITGA2 expression level was significantly decreased in AML patients after CR (p = 0.011), and was returned at the time of relapse phase (p = 0.021). Moreover, unmethylated ITGA2 promoter was identified in normal controls, leukemia cell lines, and primary leukemia cells with low or high ITGA2 expression. In conclusions, methylation‐independent ITGA2 overexpression is associated with poor prognosis in AML. Integrin α2 (ITGA2) expression was significantly upregulated in 134 de novo acute myeloid leukemia (AML) patients compared with 33 controls (p = 0.007). Furthermore, the overall survival in high ITGA2 expression patients was significantly shorter than low ITGA2 expression patients throughout AML cohort, non–acute promyelocytic leukemia (APL), and cytogenetic normal‐AML (p = 0.001, 0.002, and 0.044, respectively). Multivariate analysis confirmed that ITGA2 overexpression served as an independent prognostic factor in both whole‐cohort AML patients (p = 0.018) and non‐APL AML patients (p = 0.021). [ABSTRACT FROM AUTHOR]

DOK-1 and DOK-2 (DOK1/2) are closely related members of downstream of tyrosine kinase (DOK) family genes, which are found to be frequently rearranged in several hematopoietic cancers. However, the clinical implications of DOK1/2 in acute myeloid leukemia (AML) remain largely unknown. To investigate the clinical significance, real-time quantitative PCR (RQ-PCR)was carried out to detectDOK1/2 expressions in 125 de novo AML patients and 28 healthy controls. Real-time quantitative methylation-specific PCR (RQ-MSP) andbisulfite sequencingPCR(BSP)wereapplied todetectDOK1/2methylation level anddensity.DOK1/2expressionsweresignificantlydown-regulated inAMLpatients. The promoters of DOK1/2 were highly hypermethylated and negatively correlated with DOK1/2 expressions in AML patients. In addition, we also confirmed that DOK1/2 expressions could be restored by DOK1/2 demethylation using 5-aza-2′-deoxycytidine in leukemia cell line THP-1. Survival analyses showed that low-expressed DOK1/2 were associated withmarkedly shorter overall survival and leukemia free survival in both wholecohort AML and non-M3 AML patients. Multivariate analyses further revealed that DOK1/2 were act as independent prognostic factors in AML patients. These findings indicate that decreased DOK1/2 expressions associated with their promoter hypermethylations predict adverse prognosis in AML. [ABSTRACT FROM AUTHOR]

TET2 (Ten‐Eleven Translocation 2) gene is a member of TET family that can modify DNA through catalyzing the conversion of 5‐methylcytosine (5‐mC) into 5‐hydroxymethylcytosine (5‐hmC). Although TET2 mutation has been disclosed in a variety of hematopoietic malignancies, the prognostic implication of TET2 expression in acute myeloid leukemia (AML) remains largely elusive. In this study, real‐time quantitative PCR was carried out to detect the level of TET2 transcript in 134 de novo AML patients and 35 healthy donors. TET2 mRNA level was significantly down‐regulated in AML patients compared with controls (p = 0.010). Among the French–American–British (FAB) subtypes, the incidence of TET2 under‐expression in M0/M1 subtypes was significantly higher than in the other subtypes M2/M3/M4/M5/M6 (p = 0.017), and also markedly higher than in the other granulocyte subtypes M2/M3 (p = 0.005). TET2 low‐expressed patients showed a significantly higher frequency of NPM1 mutations than TET2 high‐expressed patients. Although there was no significant difference in complete remission rate between two groups (low and high TET2 expression), patients with low TET2 expression had markedly shorter overall survival (OS) in both non‐M3 and cytogenetically normal AML (CN‐AML) (p = 0.016 and 0.044, respectively). Furthermore, multivariate analysis confirmed the prognostic value of TET2 expression on OS among CN‐AML patients (p = 0.049). Importantly, TET2 expression in complete remission (CR) time was significantly higher than newly diagnosis time (p = 0.001), and was returned to lower level when in relapse time (p < 0.001). These findings indicated that down‐regulation of TET2 expression was a common event and acted as a prognostic and predictive biomarker in CN‐AML patients. [ABSTRACT FROM AUTHOR]

CHFR acts as a tumor suppressor gene, which is frequently inactivated caused by its promoter hypermethylation in various solid tumors. Although a recent study showed that CHFR hypermethylation was a frequent event in acute myeloid leukemia (AML) and correlated with adverse clinical outcome, herein, we found that CHFR methylation was a rare event in patients with myeloid malignancies (including AML, chronic myeloid leukemia, and myelodysplastic syndromes), but its expression may serve as an independent prognostic biomarker in AML. CHFR expression was assessed by real‐time quantitative PCR, whereas CHFR methylation was detected by methylation‐specific PCR and bisulfite sequencing PCR. In AML patients, lower CHFR expression was associated with lower complete remission (CR) rate, and CHFR expression was significantly increased in CR after chemotherapy. Moreover, patients with lower CHFR expression showed shorter overall survival and leukemia‐free survival, and multivariate analysis confirmed that lower CHFR expression was an independent risk factor in AML. Importantly, the prognostic value of CHFR expression was validated using the published Gene Expression Omnibus datasets. Notably, CHFR promoter was nearly unmethylated in patients with myeloid malignancies. Our findings revealed that lower CHFR expression was independently associated with unfavorable prognosis in AML. Moreover, aberrant CHFR promoter methylation was a rare event in myeloid malignances. [ABSTRACT FROM AUTHOR]

Accumulating studies have shown that miR-216b acted as a tumor suppressor and was down-regulated in solid tumors. However, little studies revealed the role or clinical implication of miR-216b in blood cancers. Herein, we reported miR-216b expression and its clinical significance in patients with acute myeloid leukemia (AML). In the current study, we analyzed bone marrow (BM) miR-216b expression in 115 de novo AML patients examined by real-time quantitative PCR. Notably, BM miR-216b expression was significantly up-regulated in AML patients, and could serve as a potential biomarker distinguishing AML from controls. No significant correlations of BM miR-216 expression were found with sex, age, white blood cells, hemoglobin, platelets, BM blasts, French-American-British classifications, and karyotypes. Significantly, patients with high miR-216b expression tended to have a lower frequency of FLT3-ITD mutation and higher incidence of U2AF1 and IDH1/2 mutations. Moreover, complete remission (CR) rate and overall survival were negatively affected by BM miR-216b overexpression among cytogenetically normal AML (CN-AML). Cox regression analyses showed that highBM miR-216b expression may act as an independent risk factor in CN-AML patients. Among the follow-up patients, BM miR-216b level in CR phase was markedly lower than in diagnosis time, and was returned in relapse phase. Collectively, our findings indicated that miR-216b overexpression was a frequent event in de novo AML, and independently conferred a poor prognosis in CN-AML. Moreover, miR-216b expression was a valuable biomarker correlated with disease recurrence in AML. [ABSTRACT FROM AUTHOR]

Background: Lenalidomide could effectively induce red blood cell (RBC) transfusion independence (TI) in patients with lower-risk (Low/Intermediate-1) myelodysplastic syndrome (MDS) with or without 5q deletion. However whether lenalidomide ultimately improves the overall survival (OS) of lower-risk MDS patients and reduces the progression to AML remains controversial. Method: A meta-analysis was conducted to examine the efficacy and safety of lenalidomide in the treatment of lower-risk MDS. Efficacy was assessed according to erythroid hematologic response (HI-E), cytogenetic response (CyR), OS and AML progression. Safety was evaluated based on the occurrence rates of grades 3–4 adverse events (AEs). Results: Seventeen studies were included consisting of a total of 2160 patients. The analysis indicated that the overall rate of HI-E was 58% with 95% confidence interval (CI) of 43–74%. The pooled estimates for the rates of CyR, complete CyR, and partial CyR were 44% (95% CI 19–68%), 21% (95% CI 13–30%) and 23% (95% CI 15–32%), respectively. The patients with 5q deletion had significantly higher rate of HI-E and CyR than those without 5q deletion (P = 0.002 and 0.001, respectively). The incidences of grades 3–4 neutropenia, thrombocytopenia, leukopenia, anemia, deep vein thrombosis, diarrhea, fatigue and rash were 51% (95% CI 30–73%), 31% (95% CI 20–42%), 9% (95% CI 5–13%), 7% (95% CI 2–12%), 3% (95% CI 2–5%), 3% (95% CI 1–5%), 2% (95% CI 1–4%) and 2% (95% CI 1–3%), respectively. Lenalidomide significantly improved OS (HR: 0.62, 95% CI 0.47–0.83, P = 0.001) and lowered the risk of AML progression in del(5q) patients (RR: 0.61, 95% CI 0.41–0.91, P = 0.014). Conclusions: In spite of the AEs, lenalidomide could be effectively and safely used for the treatment of lower-risk MDS patients with or without 5q deletion. [ABSTRACT FROM AUTHOR]

Recently, somatic mutations in SRSF2 gene have been discovered in a proportion of hematologic malignancies including acute myeloid leukemia (AML). This study was aimed to investigate SRSF2 mutations in Chinese AML patients. High-resolution melting analysis (HRMA) was developed to screen SRSF2 mutations in 249 cases with AML, and then direct DNA sequencing was used to verify the results of HRMA. In this study, 3.6 % (9/249) of Chinese AML patients were found with heterozygous SRSF2 mutations. Patients with SRSF2 mutations were older than those with wild-type SRSF2 ( P = 0.014). No differences in the sex, blood parameters, French-American-British classification (FAB) subtypes, and karyotypes were observed between AML patients with and without SRSF2 mutations. Although the overall survival (OS) of SRSF2-mutated patients was inferior to those without mutations in both whole AML patients (median 4 vs. 11 months, respectively; P = 0.006) and cytogenetically normal patients (median 2 vs. 12 months, respectively; P = 0.008), multiple analysis disclosed that SRSF2 mutation was not an independent prognostic factor in AML patients. These results suggest that SRSF2 mutation occurs at a low frequency in aged AML patients and might not be associated with adverse prognosis in Chinese AML patients. [ABSTRACT FROM AUTHOR]

To investigateDLX4isoforms expression and their clinical significance in acute myeloid leukemia (AML).DLX4 transcript variant 1(BP1) expression was significantly up-regulated in AML patients compared with normal controls. However,DLX4 transcript variant 2(DLX7) was significantly down-regulated in AML patients. Both in the overall AML and the non-M3 AML cohorts, those patients with highBP1expression (BP1high) showed significantly lower rates of complete remission than those with lowBP1expression (BP1low).BP1highcases had significantly shorter overall survival thanBP1lowcases in the overall AML cohort, non-M3 AML, and cytogenetically normal AML (CN-AML). Multivariate analysis confirmed the independent prognostic value ofBP1expression among both the overall AML cohort and non-M3 AML as well as CN-AML patients. However, we did not observe the impact ofDLX7expression on prognosis in AML patients. Our study reveals thatBP1overexpression serves as an independent risk factor inde novoAML patients. [ABSTRACT FROM AUTHOR]

Aberrant methylation of let-7a-3 promoter has been observed in various malignancies. However, the clinical relevance of let-7a-3 methylation remains poorly known in acute myeloid leukemia (AML). This study was to investigate the let-7a-3 methylation status and to explore its clinical significance in AML. let-7a-3 promoter was significantly hypomethylated in AML patients compared to controls (median 4.51 vs 0.49) ( P = 0.0003). Receiver operating characteristic curve (ROC) analysis discriminated all patients or cytogenetically normal patients from controls with an areas under the ROC curve (AUC) of 0.737 or 0.783, respectively ( P < 0.001). Patients with favorable/intermediate karyotypes had significantly higher let-7a-3 unmethylation than controls. Patients with DNMT3A mutations had a trend of high level of let-7a-3 unmethylation than did those with wild-type DNMT3A (median 6.76 vs 3.66, P = 0.096). There was no significant difference in overall survival between patients with and without hypomethylated let-7a-3 (median 12 vs 5 months, P = 0.103). No correlation was observed between the level of let-7a-3 expression and let-7a-3 unmethylation in AML samples ( R = 0.197, P = 0.150). However, the level of let-7a-3 expression was increased in a dose-dependent manner in THP-1 line treated with 5-aza-dC, while the methylation density of let-7a-3 promoter decreased with 5-aza-dC dose. Our findings suggest that let-7a-3 hypomethylation is associated with favorable and intermediate karyotypes but not a prognostic predictor for AML patients. Let-7a-3 expression may be partially regulated by promoter methylation. [ABSTRACT FROM AUTHOR]

Deregulation of secreted frizzled-related protein 1 ( SFRP1) has been found in many types of cancer. However, the pattern of SFRP1 expression in acute myeloid leukemia (AML) is still unclear. This study determined SFRP1 expression in patients with AML. SFRP1 expression was decreased markedly in patients with AML compared to controls ( p < 0.001). White blood cell (WBC) counts increased as SFRP1 expression decreased in AML ( p = 0.016). Patients with low SFRP1 expression showed a different distribution of French-American-British (FAB) subtypes M1/M2/M3 from those with high SFRP1 expression ( p = 0.031). NPM1 mutation was mainly observed in patients with low SFRP1 expression ( p = 0.011). There was a weak trend that patients with AML with low SFRP1 expression had shorter overall survival (OS) than those with high SFRP1 expression ( p = 0.103). Our results indicate that reduced SFRP1 expression is found more frequently in the less well-differentiated subgroups of AML and is associated with NPM1 mutation in AML. [ABSTRACT FROM AUTHOR]

Background: Aberrant expression of SRY-box containing gene 17 ( SOX17) has been observed in several solid tumors. However, little is known about SOX17 expression in acute myeloid leukemia (AML). The purpose of this study was to investigate the alteration of SOX17 expression and to explore its clinical significance in AML. Methods: Real-time quantitative PCR (RQ-PCR) was performed to analyze the status of SO1X17 expression in 103 patients with de novo AML and 26 normal controls. The clinical relevance of SOX17 expression was analyzed in AML. Results: SOX17 level in AML was significantly down-regulated compared to controls (p<0.001). Receiver operating characteristic curve (ROC) curve analysis revealed that an area under the ROC curve (AUC) of 0.834 (95% CI 0.765-0.903; p<0.0001) or 0.789 (95% CI 0.690-0.888, p<0.001) in discriminating all patients or cytogenetically normal patients from controls, respectively. The cohort of AML patients was divided into two groups according to the cut-off value of 0.017 (60% sensitivity and 100% specificity, respectively). Cytogenetically normal patients with low SOX17 expression had significantly shorter OS than those with high SOX17 expression (median 4 vs. 25 months, respectively, p=0.035). Multivariate analysis confirmed low SOX17 expression as an independent risk factor. Conclusions: Our findings indicated that low SOX17 level may define an important risk factor in AML with normal cyotgenetics. [ABSTRACT FROM AUTHOR]

Abstract: MicroRNA miR-378 plays important roles in tumorigenesis by enhancing cell survival, reducing apoptosis, promoting tumor growth, angiogenesis and promoting cell migration and invasion. Abnormal expression of miR-378 has been observed in various types of cancers. The aim of this study was to investigate the expression status of miR-378 and its clinical significance in patients with acute myeloid leukemia (AML) using real-time quantitative PCR. miR-378 overexpression was identified in 26 of 84 (31%) AML patients. The patients with miR-378 overexpression had lower hemoglobin level than those without miR-378 overexpression (66 versus 78g/L, respectively, P =0.010). The frequency of miR-378 overexpression in FAB-M2 subtype was higher than other subtypes (44% versus 20%, P =0.032). Moreover, the frequency of miR-378 overexpression was higher in patients with t(8;21) than in others (64% versus 24%, P =0.012). The status of miR-378 expression was not correlated with the mutations of eight genes (FLT3-ITD, NPM1, C-KIT, IDH1/IDH2, DNMT3A, C/EBPA and U2AF1). The difference in relapse-free survival was observed between patients with and without miR-378 overexpression (P =0.049). These findings suggest that miR-378 up-regulation is a common event and might have an adverse impact on prognosis in AML. [Copyright &y& Elsevier]

Abstract: Objective: We examined RAS mutational status and correlated this with presenting morphology, cytogenetics, clinical outcome and other gene aberrations in a large cohort of Chinese acute myeloid leukemia (AML) patients. Designs and methods: N-RAS and K-RAS were screened for mutations at hot-spot codons 12, 13 and 61 using high resolution melting analysis (HRMA) and direct DNA sequencing in 504 Chinese AML patients and their clinical relevance was analyzed. Results: The frequencies of mutations of N-RAS and K-RAS were 9.7% (49/504) and 2.9% (15/504), respectively. c.35G>A (rs121913237: G>A; p.Gly12Asp and rs121913529: G>A; p.Gly12Asp) and c.38G>A (rs121434596: G>A; p.Gly13Asp and rs112445441: G>A; p.Gly13Asp) were the most common base substitutions (46% in N-RAS and 60% in K-RAS, respectively). AML patients with RAS mutations presented significantly higher white blood cell count (WBC) at diagnosis than those without mutations (p <0.001). RAS mutations were underrepresented in patients with t(15;17) (2.9%, p =0.01), while overrepresented in cases with abn11q23 (50%, p =0.002) and inv(16) (66.6%, p =0.04). In the FAB subtypes M4 and M5, RAS mutations were more frequent (21.6% and 20.6%, respectively) than they were in other subtypes (7.5%, p =0.006 and 0.005, respectively). FLT3-ITD and RAS mutation were rarely coexistent (p =0.03). RAS mutation didn't influence overall survival (OS) either in the entire cohort or within some defined subgroups. Conclusions: RAS mutations are associated with some biologically specific subtypes of AML but don't impact clinical outcome in Chinese patients. [Copyright &y& Elsevier]

Abstract: Objective: SALL4 gene has been identified to stimulate the expansion of hematopoietic stem cell (HSCs) and enhance the self-renewal of HSCs. Overexpression of SALL4 has been found in several cancers. The present study was aimed to investigate the methylation status of SALL4 promoter region in acute myeloid leukemia (AML). Designs and methods: The methylation status of SALL4 promoter was analyzed in 84 patients with AML using methylation-specific PCR (MSP) and its clinical significance was evaluated. Results: Aberrant hypomethylation of SALL4 gene, which was correlated with SALL4 expression, was found in 17.8% (15/84) cases. The patients with SALL4 hypomethylation had significantly older age and higher WBCs than those without SALL4 hypomethylation. The incidence of SALL4 hypomethylation was higher in M1 subtype than in M2 and other subtypes (50%, 26% and 6%, respectively, P =0.001). SALL4 hypomethylation was associated with cytogenetically intermediate and poor groups. Although survival time of the SALL4-hypomethylated AML was shorter than that of SALL4-methylated group (4months vs 9months), the difference was not statistically significant (P =0.356). Conclusions: Hypomethylation of SALL4 promoter is a common event and is associated with the intermediate and poor karyotypes in AML. [Copyright &y& Elsevier]

Somatic mutations of U2AF1 gene have recently been identified in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). In this study, we analyzed the frequency and clinical impact of U2AF1 mutations in a cohort of 452 Chinese patients with myeloid neoplasms. Mutations in U2AF1 were found in 2.5% (7/275) of AML and 6.3% (6/96) of MDS patients, but in none of 81 CML. All mutations were heterozygous missense mutations affecting codon S34 or Q157. There was no significant association of U2AF1 mutation with blood parameters, FAB subtypes, karyotypes and other gene mutations in AML. The overall survival (OS) of AML patients with U2AF1 mutation (median 3 months) was shorter than those without mutation (median 7 months) (P = 0.035). No difference in the OS was observed between MDS patients with and without U2AF1 mutations. Our data show that U2AF1 mutation is a recurrent event at a low frequency in AML and MDS. [ABSTRACT FROM AUTHOR]

Abstract: The aberrant changes of tumor suppressor genes (TSGs) are now recognized as an important mechanism contributing to the development of acute myeloid leukemia (AML). CCAAT/enhancer binding protein zeta (C/EBPζ), a candidate TSG, has been found to be involved in cancers including AML. We detected the methylation status of C/EBPζ promoter in 133 patients with AML using the methylation-specific polymerase chain reaction (MS-PCR) and examined C/EBPζ transcript in 32 patients using real-time quantitative PCR. The abnormal methylation of C/EBPζ gene promoter was found in 62 (46.6%) AML cases. No correlation was found between C/EBPζ promoter hypermethylation and the age, sex, WBC counts, platelet counts and FAB subtypes of AML patients (P >0.05). The trend that the frequency of C/EBPζ methylation increased as karyotype became more adverse was observed (R =0.167, P =0.075). There was a significant correlation between C/EBPζ expression and C/EBPζ methylation in AML patients (R =0.606, P =0.002). Our data suggest that the aberrant methylation of C/EBPζ promoter may be involved in AML. [Copyright &y& Elsevier]

Abstract: Objective : The mutations of isocitrate dehydrogenase 1 (IDH1) gene have been identified in a proportion of hematologic malignancies including acute myeloid leukemia (AML). The aim of the present study was to explore the reliability of the high-resolution melting analysis (HRMA) for the identification of IDH1 R132 mutations in AML. Designs and methods : We evaluated the sensitivity of HRMA in the detection of IDH1 R132 mutation and screened IDH1 mutations in 110 AML patients using HRMA. The results of HRMA were validated by direct DNA sequencing. Results : The reproducible sensitivity of HRMA was 5% for the detection of IDH1 R132 mutation, higher than 10% of direct DNA sequencing. Heterozygous IDH1 mutations were identified in 4 (3.6%) AML cases, which were R132H in 3 cases and R132S in 1 case confirmed by DNA sequencing. Conclusion : The HRMA is a rapid, accurate, reliable, high-throughput method to screen IDH1 gene mutations. [Copyright &y& Elsevier]

Abstract: The epigenetic disturbances are recognized as an alternative mechanism contributing to the pathogenesis of acute myeloid leukemia (AML). GTPase regulator associated with focal adhesion kinase (GRAF), a putative tumor suppressor gene, was revealed with mutations and promoter methylation in AML and myelodysplastic syndrome. In this study, we investigated the methylation status of GRAF promoter in Chinese AML patients. Aberrant methylation of GRAF promoter was detected in 66.7% (88/132) of the cases analyzed. The methylation of GRAF gene could be detected in all FAB subtypes and in all cytogenetic risk groups. There were no significant differences in clinical features, FAB subtypes and cytogenetic risk groups between patients with and without GRAF methylation. GRAF transcript was significantly lower in AML group compared to controls (3.30 vs 56.06, P <0.001). Both patients with methylated GRAF gene and those without methylated GRAF gene had significantly lower GRAF transcript than controls (P <0.001). Furthermore, GRAF transcript was significantly lower in patients with methylated GRAF than those without methylated GRAF (1.64 vs 6.42, P =0.005). These findings suggest that the hypermethylation of GRAF promoter might be one of early events in the development of AML. [Copyright &y& Elsevier]

The Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway is active in both normal hematopoiesis and hematological malignancies. Moreover, Janus kinase-2 (JAK2) is the key hematopoietic kinase, and mutations together with single nucleotide polymorphisms (SNPs) of JAK2 have been thoroughly evaluated. In this study, we aimed to investigate whether the synonymous genetic polymorphism A830G in the JAK2 gene is associated with the treatment outcomes of Ara-C-based chemotherapy regimens in patients with acute myeloid leukemia (AML). A total of 152 patients with AML in a Chinese population were enrolled in our study. Peripheral blood samples drawn at the time of diagnosis were analyzed for the presence of JAK2 A830G by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS). The results showed that frequencies of the AA genotype were higher in the group 40–60 years old, higher white blood cell (WBC) patient group, homoharringtonine and Ara-C (HA) regimen group, and good therapy response group, and patients with the GG genotype were significantly associated with a higher rate of early death. We conclude that the AA and GG genotypes of JAK2 A830G might be important markers for therapy outcomes of patients with AML in a Chinese population. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Somatic mutations of SF3B1 gene have recently been identified in myelodysplastic syndrome and chronic lymphocytic leukemia. The frequency and clinical relevance of SF3B1 mutations have been rarely studied in acute myeloid leukemia (AML) and chronic myeloid leukemia (CML). The present study was aimed to analyze the frequency of SF3B1 mutations in AML and CML. Designs and methods: High-resolution melting analysis (HRMA) was established to detect the mutation hotspots (codon E622, H662, K666, and K700) of SF3B1 gene in 275 AML and 81 CML patients. Results: Heterozygous SF3B1 mutations were detected in three AML patients by HRMA. Direct DNA sequencing identified one K666T, one K666N and one K700E mutations. All three AML patients had normal karyotypes. One case also had NPM1 and DNMT3A mutations, one had FLT3 internal tandem duplication and DNMT3A mutations, and the other had NPM1 mutation. No SF3B1 mutations were detected in CML patients. Conclusions: SF3B1 mutation is a rare molecular event in Chinese AML and CML patients. [Copyright &y& Elsevier]

Background: Previous studies have disclosed up‐regulation of MIR‐378 in acute myeloid leukemia (AML), and might consequently affect the outcome of the patients. Correspondingly, hypomethylation of MIR‐378 was also identified in AML, particularly for FAB‐M2 subtype with t(8;21) chromosomal translocation. Nevertheless, the methylation status of MIR‐378 has not been illustrated in myelodysplastic syndrome (MDS). Herein we designed to understand the methylation pattern of MIR‐378 involved in MDS and clinical interrelation thereof. Methods: Real‐time quantitative methylation‐specific PCR (RQ‐MSP) was performed to evaluate the methylation degree of MIR‐378 5'‐flanking region on bone marrow mononuclear cells collected from 95 de novo MDS patients. Five gene mutations (IDH1, IDH2, DNMT3A, U2AF1, and SF3B1) were detected by high‐resolution melting analysis to further evaluate the clinical relevance of hypomethylation of MIR‐378. Results: Unmethylated level of MIR‐378 5'‐flanking region was significantly higher in MDS patients than that in controls (p =.034). Hypomethylated MIR‐378 was identified in 20 of 95 (21%) cases with MDS. Male patients appeared to be more frequent to harbor MIR‐378 hypomethylation compared to female patients (15/55, 27.3% vs. 4/40, 10.0%, p =.04). There was no significant difference in age, white blood cell counts, platelet counts, hemoglobin concentration, and karyotypes between the patients with and without MIR‐378‐hypomethylation. Distinct distribution of five gene mutations was not observed in the two groups as well. However, MIR‐378‐hypomethylated patients had significantly shorter overall survival than those without MIR‐378 hypomethylation (p =.036). Moreover, among patients <60 years, hypomethylation of MIR‐378 was confirmed to be an independent adverse prognostic factor by both Kaplan–Meier and Multivariate Cox analyses. Conclusion: Hypomethylation of MIR‐378 5'‐flanking region is an adverse prognosticator in MDS, particularly in patients <60 years. [ABSTRACT FROM AUTHOR]

Background: The Foxo3 gene, belonging to the forkhead family, is one of the classes of transcription factors characterized by a forkhead DNA-binding domain, which usually considered being a cancer suppressor gene. Circ-Foxo3 is a circular structure which connects the 3'end to the 5'end. Scholars detected that circ-Foxo3 could compete with Foxo3 for binding to some miRNAs.Methods: In this study, we will test the expression of Foxo3 and circ-Foxo3 in de novo acute myeloid leukemia (AML) patients to explore the relationship between Foxo3 gene and circ-Foxo3. All the de novo AML samples and normal control samples was measured by real-time quantitative PCR. A receiver operating characteristic curve was conducted to differentiate AML patients from control people. Association of Foxo3 expression and overall survival was conducted by Kaplan-Meier survival analysis.Results: We found that the expression of Foxo3 gene in de novo patients was significantly lower than control samples (P = 0.009). Meanwhile, circ-Foxo3 also expressed lower in de novo AML patients than in control samples (P = 0.040). In different classifications, this trend could be observed more remarkably. In non-M3 patients, the Foxo3 high patients' survival time was longer than Foxo3 low patients (P = 0.002). Besides, in non-favorable risk groups, patients with low expression of Foxo3 had longer survival time than Foxo3 high patients (P = 0.004). Furthermore, in normal Karyotypic patients, the overall survival time of patients with high-expressed Foxo3 was significantly longer than those with low expression (P = 0.034). Besides, Pearson analysis was also conducted between these two genes in AML patients. Results revealed that they were positively correlated (R = 0.63, P < 0.001).Conclusion: In conclusion, we found that low expression of circ-Foxo3 and Foxo3 were frequent in AML patients, and patients with high expression of Foxo3 often had a trend of better prognosis. [ABSTRACT FROM AUTHOR]

Background: The long non-coding RNA H19 plays a crucial role in solid tumor initiation and progression. However, the potential role of H19 and its clinical significance in acute myeloid leukemia (AML) remain largely elusive. Methods: H19 expression was detected by qPCR, and clinical significance in AML patients was further analyzed. The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) data for AML were used as validation cohorts. The roles of H19 in cell proliferation and apoptosis were determined by cell proliferation assay and flow cytometry analysis. Results: H19 expression was significantly increased in AML patients but not associated with embedded miR-675 expression. Moreover, H19 overexpression was not dependent on the methylation pattern in H19 differentially methylated region/imprinting control region. Strong association was observed between H19 overexpression and patients' characteristics including sex, higher white blood cells, older age, and intermediate karyotype, FLT3-ITD, and DNMT3A mutations. In addition, H19 overexpression correlated with lower complete remission (CR) rate and shorter overall survival, and further confirmed by multivariate analyses. Importantly, the prognostic effect of H19 expression was validated by TCGA and GEO data. In the follow-up of patients, H19 expression in CR phase was lower than diagnosis time and returned at relapse time. Loss-of-function experiments showed that H19 exhibited anti-proliferative and pro-apoptotic effects in leukemic cell HL60. Furthermore, H19 expression was positively correlated with potential downstream gene ID2 in AML. Conclusions: Our findings revealed that methylation-independent H19 was a prognostic and predictive biomarker in AML, and H19/ID2 played crucial roles in leukemogenesis with potential therapeutic target value. [ABSTRACT FROM AUTHOR]

Abstract: The reduced expression of CTNNA1 gene, a putative tumor suppressor gene, has been found in several cancers including acute myeloid leukemia (AML). CTNNA1 expression is regulated by methylation and histone deacetylation. However, the clinical significance of CTNNA1 methylation in AML is rarely known. The present study was aimed to investigate the methylation status of CTNNA1 promoter region using methylation-specific PCR (MSP) and its clinical relevance in Chinese AML patients. Patients with CTNNA1 hypermethylation had significantly lower level of CTNNA1 transcript than those without CTNNA1 hypermethylation (P =0.031). The relationship of CTNNA1 methylation with clinical parameters was evaluated. Aberrant hypermethylation of CTNNA1 gene was found in 23.9% (37/155) AML cases. The status of CTNNA1 methylation was not correlated with the mutations of seven genes (FLT3-ITD, NPM1, C-KIT, IDH1/IDH2, DNMT3A, N/K-RAS and C/EBPA). There was no significant difference in the rates of complete remission (CR) between patients with and without CTNNA1 methylation. Although the overall survival (OS) time of the CTNNA1-methylated AML was shorter than that of CTNNA1-unmethylated group (6 months vs 9 months), the difference was not statistically significant (P =0.681). Our data suggest that CTNNA1 methylation is a recurrent event but has no influence on prognosis in AML. [Copyright &y& Elsevier]

Abstract: Objective: MicroRNA miR-124 has been suggested as a tumor suppressor for its role in inhibiting cell growth, inducing differentiation and promoting apoptosis. The present study was aimed to investigate the expression status of miR-124-1 and its clinical relevance in patients with acute myeloid leukemia (AML). Designs and methods: Real-time quantitative PCR was performed to detect the expression level of miR-124-1 in AML patients. The clinical significance of miR-124-1 expression in AML was investigated. Results: miR-124-1 underexpression was identified in 30 (36%) of 83 AML patients. No significant difference could be observed in sex, age and blood parameters between the patients with and without miR-124-1 underexpression. The frequency of miR-124-1 underexpression was higher in the patients with t(15;17) than in others (62% versus 30%, P =0.040). The status of miR-124-1 expression was not correlated with the mutations of nine genes (FLT3-ITD, NPM1, C-KIT, IDH1/IDH2, DNMT3A, N/K-RAS and C/EBPA). The patients with miR-124-1 underexpression had borderline longer overall survival and relapse-free survival than those without miR-124-1 underexpression (P =0.052 and 0.045, respectively). Conclusions: These findings suggest that miR-124-1 underexpression is a common event and might have a favorable impact on prognosis in AML. [Copyright &y& Elsevier]

Background The liver-enriched microRNA-122 ( miR-122 ) plays a crucial role in pathogenesis of hepatocellular carcinoma (HCC) with prognostic value. Recently, miR-122 was also found to be related to many other cancers besides HCC. However, less study determined miR-122 expression and its clinical significance in acute myeloid leukemia (AML). Methods Real-time quantitative PCR was performed to detect the level of bone marrow (BM) miR-122 in de novo AML patients. The clinical significance of miR-122 expression in AML was further investigated. Results Among whole-cohort AML, lower expression of BM miR-122 was associated with male patients, higher hemoglobin and favorable-karyotypes ( P  = 0.038, 0.006, and 0.038, respectively). Among cytogenetically normal AML (CN-AML), lower expression of BM miR-122 was correlated with DNMT3A wild type ( P  = 0.043). Moreover, patients with lower expression of BM miR-122 presented lower complete remission (CR) rate and shorter overall survival (OS) than those with higher expression of BM miR-122 in CN-AML ( P  = 0.025 and 0.013, respectively). Cox regression analyses further confirmed the prognostic value of BM miR-122 expression in CN-AML ( P  = 0.024). In follow-up patients, BM miR-122 expression level in CR time was increased compared to diagnosis time, and was returned to primary level when in relapse time again ( P  = 0.062 and 0.049, respectively). Conclusions Our findings indicated that lower expression of BM miR-122 acted as an independent risk factor for OS in CN-AML. [ABSTRACT FROM AUTHOR]