Better Failure-Free Survival and Graft-versus-Host Disease-Free/Failure Free Survival with Fludarabine-Based Conditioning in Stem Cell Transplantation for Aplastic Anemia in Children.

BACKGROUND: This study aimed to assess the outcome of stem cell transplantation (SCT), including overall survival (OS), failure-free survival (FFS) and graft-versus-host disease (GvHD)-free/failure-free survival (GFFS), and to analyze prognostic factors in children with aplastic anemia (AA). METHODS: From 1991 to 2018, 43 allogeneic SCT recipients were enrolled in the study to investigate the demographic characteristics, survival outcomes and prognostic factors. RESULTS: With the median follow-up of 7.1 years, the estimated 10-year OS, FFS, GFFS were 86.0%, 60.5%, and 51.2%, respectively. Matched related donors (MRD, n = 28) showed better 10-year OS than unrelated donors (n = 15) (96.4% vs. 66.7%; P = 0.006). Engraftment failure was seen in 13 patients (30.2%). Donor-type aplasia was seen in 13.8% (4/29) after fludarabine (Flu)-based conditioning (Flu-group), while in 42.6% (6/14) after cyclophosphamide (Cy)-based regimen (Cy-group) (P = 0.035). Six patients died. The 10-year OS in Cy-group was 92.9% (n = 14, all MRD), while that of Flu-group was 82.1% (n = 29; P = 0.367). But Flu-group tended to have better FFS and GFFS than Cy-group, although Flu-group had less MRDs (41.4% vs. 100%; P = 0.019), and higher proportion of previous immunosuppressive treatment (IST; 62% vs. 21.4%, P = 0.012). In MRD transplants, OS was similar between Flu-group (100%, n = 14) and Cy-group (92.9%, n = 14), while FFS (100.0% vs. 42.9%; P = 0.001) and GFFS (85.7% vs. 35.7%; P = 0.006) were significantly better in Flu-group. Stem cell sources, irradiation in the conditioning, and method of GvHD prophylaxis did not significantly influence the outcome. CONCLUSION: This study reviewed SCT outcomes for pediatric AA with changes of transplant strategies over the last 25 years. The FFS and GFFS were higher in Flu-group than in Cy-group, especially in matched related transplantation. Graft failure including donor-type aplasia remains troublesome even with Flu-based conditioning. Further refinement of transplant strategies to ensure better quality-of-life should be pursued.

Biphenotypic acute leukemia or acute leukemia of ambiguous lineage in childhood: clinical characteristics and outcome.

BACKGROUND: Acute leukemia (AL), not clearly assigned to myeloid, B-lymphoid, or T-lymphoid lineage, is classified as either biphenotypic acute leukemia (BAL) based on the European Group for Immunological Classification of Leukemias (EGIL) or acute leukemia of ambiguous lineage (ALAL) encompassing acute undifferentiated leukemia (AUL) and mixed-phenotype acute leukemia (MPAL) based on the World Health Organization (WHO) criteria. METHODS: Medical records of children newly diagnosed with BAL or ALAL, based on the EGIL or the 2008/2016 WHO criteria, respectively, admitted at Chonnam National University Hospital in 2001-2017 were retrospectively reviewed. RESULTS: Twelve (3.2%) of 377 AL patients satisfied the BAL or ALAL definitions based on the EGIL or the WHO criteria, respectively. Among 12 patients including 11 with BAL and another with undefined case based on the EGIL criteria, 7 (1.9%) had ALAL based on more stringent 2016 WHO criteria (AUL, 2; MPAL, 5). One patient had MPAL with t(9;22)(q34;q11.2), BCR-ABL+, and two had MLL gene abnormality. ALL-directed regimen was associated with better complete remission rate compared with AML-directed regimen (100.0% vs. 16.7%; P=0.015). The 5-year overall survival (OS) and event-free survival (EFS) were 51.1±15.8% and 51.9±15.7%, respectively. AUL was associated with poor OS and EFS compared with MPAL (0.0% vs. 75.0±21.7%; P=0.008). CONCLUSION: Due to the rarity of the cases, future multicenter, prospective studies incorporating large number of cases are urgently warranted to identify the clinical, biologic, and molecular markers for the prediction of prognosis and determine the best tailored therapy for each patient.

Chemical Composition, Antioxidant and Anti-melanogenic Activities of Essential Oils from Chrysanthemum boreale Makino at Different Harvesting Stages.

In the present study, the chemical compositions and skin whitening-related antioxidant and anti-melanogenic effect of essential oils (EOs) extracted from Chrysanthemum borealeMakino (CBM) (CBMEOs) at vegetative, pre-flowering and full-flowering are investigated and contrasted among the three stages. The yields and components of the CBMEOs were different at each stage. The CBMEOs increased DPPH and ABTs scavenging activities and attenuated the α-melanocyte stimulating hormone (α-MSH)-induced tyrosinase activity and melanin synthesis in B16BL6 cells. Among CBMEO components, eugenol had the highest DPPH and ABTs scavenging activities and cuminaldehyde was the strongest inhibitor of α-MSH-induced tyrosinase activity and melanin synthesis. The CBMEOs in each stage showed the different levels of phosphorylation of extracellular signal-regulated kinase1/2 and p38 MAPK. These findings demonstrate that the CBMEOs have antioxidative and anti-melanogenic activities in all the CBM harvesting stages, resulting in skin-whitening biological activities and that the levels of their component contents and bioactivities differ among the CBM harvesting stages. The CBMEOs may have the potential for use in cosmetics and alternative medicine.

Small heat shock proteins can release light dependence of tobacco seed during germination.

Small heat shock proteins (sHSPs) function as ATP-independent molecular chaperones, and although the production and function of sHSPs have often been described under heat stress, the expression and function of sHSPs in fundamental developmental processes, such as pollen and seed development, have also been confirmed. Seed germination involves the breaking of dormancy and the resumption of embryo growth that accompany global changes in transcription, translation, and metabolism. In many plants, germination is triggered simply by imbibition of water; however, different seeds require different conditions in addition to water. For small-seeded plants, like Arabidopsis (Arabidopsis thaliana), lettuce (Lactuca sativa), tomato (Solanum lycopersicum), and tobacco (Nicotiana tabacum), light is an important regulator of seed germination. The facts that sHSPs accumulate during seed development, sHSPs interact with various client proteins, and seed germination accompanies synthesis and/or activation of diverse proteins led us to investigate the role of sHSPs in seed germination, especially in the context of light dependence. In this study, we have built transgenic tobacco plants that ectopically express sHSP, and the effect was germination of the seeds in the dark. Administering heat shock to the seeds also resulted in the alleviation of light dependence during seed germination. Subcellular localization of ectopically expressed sHSP was mainly observed in the cytoplasm, whereas heat shock-induced sHSPs were transported to the nucleus. We hypothesize that ectopically expressed sHSPs in the cytoplasm led the status of cytoplasmic proteins involved in seed germination to function during germination without additional stimulus and that heat shock can be another signal that induces seed germination.

Tobacco class I cytosolic small heat shock proteins are under transcriptional and translational regulations in expression and heterocomplex prevails under the high-temperature stress condition in vitro.

Seven genomic clones of tobacco (Nicotiana tabacum W38) cytosolic class I small heat shock proteins (sHSPs), probably representing all members in the class, were isolated and found to have 66 to 92% homology between their nucleotide sequences. Even though all seven sHSP genes showed heat shock-responsive accumulation of their transcripts and proteins, each member showed discrepancies in abundance and timing of expression upon high-temperature stress. This was mainly the result of transcriptional regulation during mild stress conditions and transcriptional and translational regulation during strong stress conditions. Open reading frames (ORFs) of these genomic clones were expressed in Escherichia coli and the sHSPs were purified from E. coli. The purified tobacco sHSPs rendered citrate synthase and luciferase soluble under high temperatures. At room temperature, non-denaturing pore exclusion polyacrylamide gel electrophoresis on three sHSPs demonstrated that the sHSPs spontaneously formed homo-oligomeric complexes of 200 ∼ 240 kDa. However, under elevated temperatures, hetero-oligomeric complexes between the sHSPs gradually prevailed. Atomic force microscopy showed that the hetero-oligomer of NtHSP18.2/NtHSP18.3 formed a stable oligomeric particle similar to that of the NtHSP18.2 homo-oligomer. These hetero-oligomers positively influenced the revival of thermally inactivated luciferase. Amino acid residues mainly in the N-terminus are suggested for the exchange of the component sHSPs and the formation of dominant hetero-oligomers under high temperatures.

Tobacco mitochondrial small heat shock protein NtHSP24.6 adopts a dimeric configuration and has a broad range of substrates.

There is a broad range of different small heat shock proteins (sHSPs) that have diverse structural and functional characteristics. To better understand the functional role of mitochondrial sHSP, NtHSP24.6 was expressed in Escherichia coli with a hexahistidine tag and purified. The protein was analyzed by non-denaturing PAGE, chemical cross-linking and size exclusion chromatography and the H6NtHSP24.6 protein was found to form a dimer in solution. The in vitro functional analysis of H6NtHSP24.6 using firefly luciferase and citrate synthase demonstrated that this protein displays typical molecular chaperone activity. When cell lysates of E. coli were heated after the addition of H6NtHSP24.6, a broad range of proteins from 10 to 160 kD in size remained in the soluble state. These results suggest that NtHSP24.6 forms a dimer and can function as a molecular chaperone to protect a diverse range of proteins from thermal aggregation.

A sclerosing stromal tumor of the ovary with masculinization in a premenarchal girl.

A sclerosing stromal tumor of the ovary is an extremely rare benign tumor; it usually is found during the second and third decades of life. Patients present with pelvic pain or a palpable abdominal mass. Hormonal effects such as masculinization are uncommon. Here, an 11-year old premenarchal girl presented with deepening of the voice. In addition, clitoromegaly and hirsutism with a male suprapubic hair pattern were observed. The laboratory findings showed that the testosterone level was elevated to 3.67 ng/mL, andostenedione to above 10 ng/mL, dehydroepiandrosterone-sulfate to 346 µg/dL and 17-hydroxy progesterone (17-OHP) to 11.28 ng/mL. The chromosome evaluation revealed a 46,XX female karyotype. An adrenocorticotropic hormone stimulation test was performed. The 17-OHP to cortisol ratio in 30 minutes was 0.045, which suggested a heterozygote for the 21-hydroxylase deficiency. However, the CYP21A2 gene encoding steroid 21-hydroxylase showed normal. The pelvic ultrasound showed a heterogeneous mass consisting of predominantly solid tissue in the pelvic cavity. The pelvic magnetic resonance imaging revealed an 8.9×6.2×6.6 cm mass of the left ovary. A left oophrectomy was performed and microscopic examination confirmed a sclerosing stromal tumor. Immunohistochemical studies showed that the tumor was positive for smooth muscle actin and vimentin, but negative for S-100 protein and cytokeratin. Following surgery, the hormone levels returned to the normal range and the hirsutism resolved.

Biochemical analysis of a cytosolic small heat shock protein, NtHSP18.3, from Nicotiana tabacum.

Small heat shock proteins (sHSPs) are widely distributed, and their function and diversity of structure have been much studied in the field of molecular chaperones. In plants, which frequently have to cope with hostile environments, sHSPs are much more abundant and diverse than in other forms of life. In response to high temperature stress, sHSPs of more than twenty kinds can make up more than 1% of soluble plant proteins. We isolated a genomic clone, NtHSP18.3, from Nicotiana tabacum that encodes the complete open reading frame of a cytosolic class I small heat shock protein. To investigate the function of NtHSP18.3 in vitro, it was overproduced in Escherichia coli and purified. The purified NtHSP18.3 had typical molecular chaperone activity as it protected citrate synthase and luciferase from high temperature-induced aggregation. When E. coli celluar proteins were incubated with NtHSP18.3, a large proportion of the proteins remained soluble at temperatures as high as 70 degrees . Native gel analysis suggested that NtHSP18.3 is a dodecameric oligomer as the form present and showing molecular chaperone activity at the condition tested. Binding of bis-ANS to the oligomers of NtHSP18.3 indicated that exposure of their hydrophobic surfaces increased as the temperature was raised. Taken together, our data suggested that NtHSP18.3 is a molecular chaperone that functions as a dodecameric complex and possibly in a temperature-induced manner.