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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]

Accumulating studies have proved EZH2 dysregulation mediated by mutation and expression in diverse human cancers including AML. However, the expression pattern of EZH2 remains controversial in acute myeloid leukaemia (AML). EZH1/2 expression and mutation were analysed in 200 patients with AML. EZH2 expression was significantly decreased in AML patients compared with normal controls but not for EZH1 expression. EZH2 mutation was identified three of the 200 AML patients (1.5%, 3/200), whereas none of the patients harboured EZH1 mutation (0%, 0/200). EZH2 expression and mutation were significantly associated with −7/del(7) karyotypes. Moreover, lower EZH2 expression was associated with older age, higher white blood cells, NPM1 mutation, CEBPA wild‐type and WT1 wild‐type. Patients with EZH2 mutation showed shorter overall survival (OS) and leukaemia‐free survival (LFS) than patients without EHZ2 mutation after receiving autologous or allogeneic haematopoietic stem cell transplantation (HSCT). However, EZH2 expression has no effect on OS and LFS of AML patients. Notably, in EZH2 low group, patients undergone 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 HSCT patients in EZH2 high group. Collectively, EZH2 dysregulation caused by mutation and under‐expression identifies specific subtypes of AML EZH2 dysregulation may be acted as potential biomarkers predicting prognosis and guiding the treatment choice between transplantation and chemotherapy. [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]

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]

Background Somatic mutations in SETBP1 gene have recently been detected in hematologic malignancies. The present study aimed to explore the frequency and clinical correlations of SETBP1 mutations in patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). Methods In this study, we used high-resolution melting analysis (HRMA) to detect the SETBP1 mutations in a cohort of 363 patients with AML or MDS. Results A total of 1.2% (3/249) of AML and 1.8% (2/114) of MDS patients were found with heterozygous SETBP1 mutations. In AML, patients with SETBP1 mutations showed higher hemoglobin ( P  = 0.004) and were more frequently recurrent in AML-M4 subtype ( P  = 0.034). All five SETBP1 mutated patients had normal karyotypes. The patients with SETBP1 mutations had significantly higher incidences of concurrent SRSF2 mutations ( P  = 0.002). HRMA could detect SETBP1 mutations with 5% sensitivity, obviously higher than 25% of Sanger sequencing. Conclusions We established a rapid, inexpensive, high-throughput and sensitive method to screen SETBP1 mutations. SETBP1 mutations were a rare molecular event in AML and MDS patients. [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]

Hypermethylation of distal-less homeobox 4 ( DLX4) has been increasingly identified in several cancers. Our study was aimed to determine the role of DLX4 methylation in regulating DLX4 expression and further analyze its clinical significance in de novo acute myeloid leukemia (AML) patients. DLX4 methylation level was detected by real-time quantitative methylation-specific PCR and bisulfite sequencing PCR. Treatment with 5-aza-2′-deoxycytidine (5-aza-dC) was used for demethylation studies. Clinical significance of DLX4 methylation was obtained by the comparison between the patients with and without DLX4 methylation. DLX4 was significantly methylated in AML patients compared with controls ( P < 0.001). DLX4 methylation was negatively associated with DLX7 (the shorter DLX4 isoform) ( R = −0.202, P = 0.021) but not BP1 (the longer DLX4 isoform) ( R = −0.049, P = 0.582) expression in AML patients. DLX7 and BP1 messenger RNA (mRNA) were significantly increased after 5-aza-dC treatment in leukemic cell lines THP1 and Kasumi-1. DLX4 methylated patients showed significantly higher frequency of U2AF1 mutation compared with DLX4 unmethylated patients ( P = 0.043). Both all AML and non-M3 patients with DLX4 methylation presented significantly lower complete remission rate than those with DLX4 unmethylation ( P = 0.001 and <0.001, respectively). DLX4 methylated cases had significantly shorter overall survival than DLX4 unmethylated cases among both all AML ( P = 0.003), non-M3 AML ( P = 0.001), and cytogenetically normal AML ( P = 0.032). Multivariate analysis confirmed that DLX4 methylation was independent risk factor in both all AML and non-M3 patients. Our study indicates that DLX4 hypermethylation is negatively associated with DLX7 expression and predicts poor clinical outcome in de novo AML patients. [ABSTRACT FROM AUTHOR]

Background: Methylation-associated SOX family genes have been proved to be involved in multiple essential processes during carcinogenesis and act as potential biomarkers for cancer diagnosis, staging, prediction of prognosis, and monitoring of response to therapy. Herein, we revealed SOX30 methylation and its clinical implication in acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). Results: In the discovery stage, we identified that SOX30 methylation, a frequent event in AML, was negatively associated with SOX30 expression and correlated with overall survival (OS) and leukemia-free survival (LFS) in cytogenetically normal AML among SOX family members from The Cancer Genome Atlas (TCGA) datasets. In the validation stage, we verified that SOX30 methylation level was significantly higher in AML even in MDS-derived AML compared to controls, whereas SOX30 hypermethylation was not a frequent event in MDS. SOX30 methylation was inversely correlated with SOX30 expression in AML patients. Survival analysis showed that SOX30 hypermethylation was negatively associated with complete remission (CR), OS, and LFS in AML, where it only affected LFS in MDS. Notably, among MDS/AML paired patients, SOX30 methylation level was significantly increased in AML stage than in MDS stage. In addition, SOX30 methylation was found to be significantly decreased in AML achieved CR when compared to diagnosis time and markedly increased in relapsed AML when compared to the CR population. Conclusions: Our findings revealed that SOX30 methylation was associated with disease progression in MDS and acted as an independent prognostic and predictive biomarker in AML. [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]

Background Accumulating studies have linked the disruptions of microRNA-10 ( miR-10 ) to acute myeloid leukemia (AML) with NPM1 mutation. However, miR-10 expression and its clinical implication in AML remain poorly defined. Although a recent report showed high serum level of miR-10a was associated with adverse prognosis in AML, herein, we found bone marrow (BM) miR-10 overexpression was not a prognostic biomarker in AML. Methods BM miR-10 expression was examined by real-time quantitative PCR in BM mononuclear cells in 115 de novo AML patients and 45 controls. Results BM miR-10 ( miR-10a/b ) expression was significantly up-regulated in AML patients, and was positively correlated with each other. Overexpression of miR-10a was associated with lower percentage of BM blasts, whereas miR-10b overexpression tended to correlate with higher percentage of BM blasts. Importantly, miR-10a overexpression was significantly associated with FAB-M3/t(15;17) subtypes and NPM1 mutation, meanwhile, overexpression of miR-10b was correlated with NPM1 and DNMT3A mutations. However, miR-10a/b overexpression was not associated with complete remission rate, and did not have an impact on both leukemia free survival and overall survival time in non-M3 AML patients without NPM1 mutation. Conclusions BM miR-10 overexpression is associated with genetic events but not affects clinical outcome in AML. [ABSTRACT FROM AUTHOR]

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]