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Key Points• A comprehensive study of 19 gene mutations and their cooperation, including the first report of ASXL1 and TET2 mutations in pediatric AML.• The development of pediatric AML requires fewer gene mutations than adult AML.Gene mutations involving epigenetic regulators recently have been described in adult acute myeloid leukemia (AML). Similar studies are limited in children. We analyzed gene mutations and cooperation in pediatric AML with special reference on mutated epigenetic regulators. Nineteen gene mutations, including 8 class I genes, 4 class II genes, WT1 and TP53 (class III), and 5 epigenetic regulator genes (class IV), were analyzed in 206 children with de novo AML. Mutational analysis was performed with polymerase chain reaction2 based assay followed by direct sequencing. One hundred seventeen of 206 patients (56.8%) had at least one mutation: 51% class I, 13% class II, 6.8% class III, and 5.6% class IV. FLT3-internal tandem duplication was most frequent, and 29% of patients had more than one gene mutation. Two patients carried ASXL1 mutations, both with t(8;21), 2 had DNMT3A mutations, 2 had IDH1 mutations, 1 had IDH2 mutation, and 3 had TET2 mutations. Both patients with IDH1 mutations had AML-M0 subtype and MLL-partial tandem duplication. Cooperating mutations with mutated epigenetic regulators were observed in 8 of 10 patients. We conclude that mutated epigenetic regulators were much less than those in adult AML but with frequent cooperating mutations. ASXL1, TET2, and IDH1 mutations were associated with specific genetic subtypes. (Blood. 2013;121(15):2988-2995 IntroductionComprehensive analyses in de novo childhood acute myeloid leukemia (AML) of gene mutations involving epigenetic regulators have been limited. The ASXL1 (additional sex comb-like 1) gene mapping to chromosome 20q acts as a cofactor of retinoic acid receptor via binding to steroid receptor coactivation-1 and belongs to enhancer of trithorax and polycomb genes that can both activate and repress the HOX gene.1,2 Very recently, it has been demonstrated that ASXL1 loss-of-function mutations result in the loss of polycomb repressive complex 22mediated histone H3 lysine 27 trimethylation, which promotes myeloid leukemia transformation.3 ASXL1 mutations conferred a poor outcome in adult AML, 4,5 but there have been no reports of ASXL1 mutations in childhood AML. TET proteins encode a-ketoglutarate-dependent oxygenases, which are involved in the conversion of 5-methylcytosine to 5-hydroxymethylcytosine. 6 TET2 protein is important for normal myelopoiesis, and disruption of TET2 enzymatic activity results in altered DNA methylation and favors myeloid neoplasm transformation.7 IDH1 and IDH2 mutations convert a-ketoglutarate to 2-hydroxyglutarate, which disrupts TET2 function. 8,9 Somatic mutations of TET2 were identified with microdeletion at 4q24 in myeloid neoplasms by the use of high-resolution single-nucleotide polymorphism microarrays.10,11 TET2 mutations were detected in adult AML with a frequency ranging from 7% to 23%, but t...

Natural products play an important role in promoting health with relation to the prevention of chronic inflammation. N(6)-(2-Hydroxyethyl)adenosine (HEA), a physiologically active compound in the medicinal mushroom Cordyceps cicadae, has been identified as a Ca(2+) antagonist and shown to control circulation and possess sedative activity in pharmacological tests. The fruiting body of C. cicadae has been widely applied in Chinese medicine. However, neither the anti-inflammatory activities of HEA nor the fruiting bodies of C. cicadae have been carefully examined. In this study, we first cultured the fruiting bodies of C. cicadae and then investigated the anti-inflammatory activities of water and methanol extracts of wild and artificially cultured C. cicadae fruiting bodies. Next, we determined the amount of three bioactive compounds, adenosine, cordycepin, and HEA, in the extracts and evaluated their synergistic anti-inflammatory effects. Moreover, the possible mechanism involved in anti-inflammatory action of HEA isolated from C. cicadae was investigated. The results indicate that cordycepin is more potent than adenosine and HEA in suppressing the lipopolysaccharide (LPS)-stimulated release of pro-inflammatory cytokines by RAW 264.7 macrophages; however, no synergistic effect was observed with these three compounds. HEA attenuated the LPS-induced pro-inflammatory responses by suppressing the toll-like receptor (TLR)4-mediated nuclear factor-κB (NF-κB) signaling pathway. This result will support the use of HEA as an anti-inflammatory agent and C. cicadae fruiting bodies as an anti-inflammatory mushroom.

Parenteral administration of mercuric chloride (HgCl2) to rats enhanced lipid peroxidation in liver, kidney, lung, testis, and serum (but not in heart, spleen, or muscle), as measured by the thiobarbituric acid reaction for malondialdehyde (MDA) in fresh tissue homogenates and body fluids. After sc injection of HgCl2 (5 mg/kg body wt), MDA concentrations in liver and kidney became significantly increased by 9 h and reached peak values at 24 h. Dose-response studies were carried out with male albino rats of the Fisher-344 strain (body wt 170-280 g) injected with 1, 3, 5 mg Hg/kg as HgCl2 and sacrificed after 24 h. In time-response studies, animals were administered 5 mg Hg/kg as HgCl2 and sacrificed after 3, 9, 18, 24, and 48 h. Studies in the authors' laboratory have shown that (1) concentrations of MDA are increased in targets (liver, kidney, lung, and testis) of HgCl2-treated rats; (2) severity of hepatotoxicity and nephrotoxicity is generally consistent with the elevation of Hg and MDA concentrations, based upon the time-course and dose-effect relationships observed after administration of HgCl2 to rats; and (3) concentrations of MDA are reduced in target tissues after pre-treatment with antioxidants and chelators to HgCl2-treated rats. The results of this study implicate that the lipid peroxidation is one of the molecular mechanisms for cell injury in acute HgCl2 poisoning.

Blackfoot disease is a peripheral vascular disease resulting in gangrene of the lower extremities. Although extensive epidemiological study has implicated high arsenic content in artesian well water in the endemic area, there is more to learn about the etiology of the disease. In this study, effort is paid on multielement determination and arsenic speciation in order to find out whether the trace element concentration pattern in well water in the Blackfoot disease endemic area is different from those of two control areas. Experimental results indicate that the concentrations of Fe, P, Na, and Ba in well water in the Blackfoot disease endemic area are found to be significantly higher than those of the controls, but they are still below the drinking water standard. The total arsenic in well water in the endemic area (671 +/- 149 ppb) is much higher than that of one normal control area of Hsin-Chu (< 0.7 ppb), but is a similar level as that of other control areas of I-Lan (653 +/- 71 ppb) where no Blackfoot disease has ever been found. It was also found that the insoluble arsenic in the endemic area (21.9 ppb) is much higher than that in two control areas (< or = 1.8 ppb), and the concentration ratio between As(III) and As(V) species in the endemic area (2.6) is much lower than that in one of the control areas, where the total arsenic is also high (14.7). The possible connection of Blackfoot disease with trace elements, arsenic species, and possibly other as yet undefined environmental factors in the artesian well water, is discussed.