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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: 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]

Abstract: The abnormalities of SALL4 gene, which encodes a zinc-finger transcription factor and is essential for developmental events, have been found to be involved in tumorigenesis. In this study, we investigated the methylation status of the CpG island of SALL4 promoter region in myelodysplastic syndrome (MDS) using methylation-specific PCR (MSP). Aberrant hypomethylation of SALL4 gene was found in 21.7% (18/83) of the cases analyzed. A significantly positive correlation was identified between the level of SALL4 transcript and the status of SALL4 hypomethylation (R =0.641, P <0.001). No correlation was found between SALL4 hypomethylation and clinical parameters. However, the frequency of SALL4 hypomethylation significantly increased in higher risk MDS (14% in Low/Int-1 versus 39% in Int-2/High, P =0.031). The association between SALL4 hypomethylation and the mutations in three methylation modifiers (IDH1, IDH2 and DNMT3A) was not observed. Although the estimated 50% survival time of the SALL4-hypomethylated group was shorter than that of SALL4-methylated group (11.0 months vs. 20.0 months), the difference was not statistically significant (P =0.430). These findings suggest that hypomethylation of SALL4 promoter is a common event in MDS. [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]

The article presents information on effect of abnormal hypomethylation of DDX43, a cancer/testing gene, enhances myelodysplastic syndrome (MDS). It mentions that patients with DDX43 methylation and patients without DDX43 methylation differed only in their clinical characteristic of hemoglobin level. A table depicting DDX43 hypomethylation in MDS patient and two graphs depicting survival of MDS patient are presented.

The somatic mutations of isocitrate dehydrogenase genes (IDH1 and IDH2) have been identified in a proportion of hematologic malignancies. We examined IDH1 R132 and IDH2 R140/R172 mutations by high resolution melting analysis and direct sequencing in Chinese patients with different myeloid malignancies including 198 acute myeloid leukemia (AML), 82 myelodysplastic syndrome (MDS), 85 chronic myeloid leukemia, and 57 myeloproliferative neoplasms. IDH1 and IDH2 mutations were found in four (2.0%) and ten (5.0%) AML and in two (2.4%) and three (3.6%) MDS cases, but not in other patients. IDH1 and IDH2 mutations were heterozygous and mutually exclusive. IDH1/2 mutations were significantly more frequently observed in cytogenetically normal AML or MDS compared to those without mutations. There was no difference in overall survival of both AML and MDS patients with or without IDH1/2 mutations ( P = 0.177 and 0.407, respectively). In conclusion, IDH1/2 mutations are recurrent but rare molecular aberrations in Chinese AML and MDS. [ABSTRACT FROM AUTHOR]

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]