ALBERT

Description: The effects of surface treatment of flax fibers featuring vinyltrimethoxy silane (VTMO) and maleic anhydride-polypropylene (MAPP) on the mechanical properties of flax/PP composites were investigated. α-polypropylene (α-PP) and β-polypropylene (β-PP) were used as matrices for measuring the mechanical properties of the flax fiber/polypropylene (flax/PP) composites. Flax/PP composites composed of double-covered uncommingled yarn (DCUY) were prepared using a film-stacking technique. The influence of surface treatment on the tensile, flexural, impact, and water uptake properties of Flax/PP composites were investigated. MAPP treatment was suitable for flax/PP composites in terms of superior tensile and impact properties. VTMO treatment showed superior flexural properties and less influence on the impact properties after moisture absorption.

Description: Background and purpose ASXL1 and EZH2 are histone modifiers. Mutations of ASXL1 and EZH2 genes have been described in both myelodyspolastic syndromes (MDS) and acute myeloid leukemia (AML). The role of ASXL1 or EZH2 mutations in the progression from MDS to secondary AML (sAML) is unclear. We aimed to determine the clinical relevance of ASXL1 and EZH2 mutations in patients with MDS and to investigate the role of ASXL1 or EZH2 mutation with its cooperating mutated genes in sAML progression. Methods ASXL1 and EZH2 mutations were analyzed on bone marrow samples from 126 patients with de novo MDS (45 RAEB1, 53 RAEB2, 24 RCMD and 4 RARS). Paired matched MDS/sAML samples were available for ASXL1 mutational analysis in 58 patients and for EZH2 in 54 patients. Mutational analysis of ASXL1 exon 12 was performed by PCR assays followed by direct sequencing, EZH2 mutations were first screened with denaturing high-performance liquid chromatography on amplified PCR fragments covering the whole coding sequencing from exons 2 to 20 of EZH2 gene followed by sequencing of the abnormal profile. Additional 20 known gene mutations in myeloid neoplasms were also examined in patients carrying ASXL1 or EZH2 mutations. Relative allele frequency was determined by pyrosequencing. Results Among the 126 patients, ASXL1 mutations were detected in 18 (14.3%) patients and EZH2 in 11 patients (8.7%), 3 of them had both mutations. Taken together, 20.6% of patients carried mutations of ASXL1 and/or EZH2. ASXL1-mutated patients had male predominance (17 out of 18 patients, P=0.012) and fewer circulating blasts (P=0.007). ASXL1-mutated and -unmutated patients had no difference in hemoglobin levels, white blood cell counts, platelet counts, cytogenetics, WHO subtypes, bone marrow blasts, IPSS-R or risk to sAML. ASXL1 mutations had no impact on overall survival (P=0.765) or time to sAML transformation (P=0.605). No significant difference was observed between EZH2 mutation status and clinicohematologic features or outcomes. Of the 58 paired samples, ASXL1 mutations were detected in 8 cases at diagnosis of MDS, all were also present at the time of sAML progression with no difference in the mutant allele burden (P=0.614), 2 patients acquired ASXL1 mutations. Five had EZH2 mutations at both phases of disease which exhibited a similar allele frequency (P= 0.434), none lost and one acquired EZH2 mutation at sAML phase. Progression to sAML was accompanied by additional gene mutations including RUNX1 (n=4), TET2 (n=3), CEBPα (n=2), PTPN11 (n=2), and one each for FLT3-ITD, CBL, MLL-PTD, DNMT3A, IDH2 and EZH2 in ASXL1-mutated patients; TET2 (n=4), RUNX1 (n=3), N-RAS (n=2) and single cases for DNMT3A, IDH1, and ASXL1 in EZH2-mutated patients. Cooperating mutations were either detected in both MDS and sAML samples or newly appeared in sAML samples except one who lost JAK2V617F mutation while acquired EZH2 and N-RAS mutations during sAML progression. Conclusions Our study on a large cohort of paired MDS and sAML samples demonstrated that ASXL1 or EZH2 mutations remained stable at both phases of disease in most patients. Clonal evolution can occur and cooperation of additional gene mutations is frequently detected in patients harboring ASXL1 or EZH2 mutations in the progression of MDS to sAML. Grant support This work was supported by NHRI-EX102-10003NI and DOH102-TD-C-111-006, Taiwan. Disclosures: No relevant conflicts of interest to declare.

Description: Background and purpose: Chronic myeloproliferative neoplasms (MPN) may transform into secondary acute myeloid leukemia (sAML). The genetic evolution pattern is important in understanding the pathogenesis of sAML transformation. We aimed to determine the profile of genetic evolution by examining a cohort of paired samples collected at both MPN and sAML phases using a panel of commonly mutated genes involved in myeloid neoplasms. Methods: Mutational analyses of 14 genes (JAK2V617F, CALR, ASXL1, IDH1, IDH2, TET2, DNMT3A, EZH2, KRAS, RUNX1, TP53, WT1, CBL, and SRSF2) were performed on the paired matched samples at diagnosis and at sAML transformation from 22 patients with MPN (6 polycythemia vera, 5 essential thrombocythemia, and 11 primary myelofibrosis). The samples were analyzed by polymerase chain reaction (PCR)-based assays followed by direct sequencing. For CALRmutational analysis, the PCR products of exon 9 were analyzed by GeneScan for screening deletions and insertions, then validated by Sanger sequencing. The allele frequencies of all mutated genes were determined by pyrosequencing assays in samples harboring any detectable mutations. Results: At the MPN phase, JAK2V617F was the most common mutation (N=12), followed by CALR (N=9). At sAML phase, JAK2V617F was not detected in 4 patients who had JAK2V617F at initial diagnosis while all 9 patients retained CALR mutations. Mutations of epigenetic modifier genes were detected in 13 patients (59%) at MPN phase, including TET2 (N=5), EZH2 (N=4), ASXL1 (N=2), DNMT3A (N=2), IDH1 and IDH2 (N=1 for each). One MPN sample was also found carrying RUNX1 mutation. Acquisition of 12 mutations was found in 11 patients at the sAML phase, including RUNX1 (N=4), KRAS (N=3), IDH2 (N=2), and one each of CBL, ASXL1 and TP53. Except JAK2V617F and TET2 mutations, the mutations present in the MPN phase remained detectable at sAML transformation. The allele frequencies of IDH2 and EZH2 mutant clones were apparently increased at sAML phase. Of note, two patients had double TET2 mutations at the MPN phase, clonal selection of TET2 mutants was explicitly demonstrated in both cases, with disappearance of one clone and expansion of the other during sAML transformation. The median time from MPN to sAML was 71.6 months and the median overall survival was 73.2 months for the cohort of MPN patients who had sAML transformation later on. Female patients had a trend towards lower incidence of CALR mutation (2/11 vs. 7/11, P=0.08) and significantly shorter overall survival (43.3 vs. 129.2 months, P