Jianda Hu

Exome sequencing identifies somatic mutations of DDX3X in natural killer/T-cell lymphoma

Natural killer/T-cell lymphoma (NKTCL) is a malignant proliferation of CD56+ and cytoCD3+ lymphocytes with aggressive clinical course, which is prevalent in Asian and South American populations. The molecular pathogenesis of NKTCL has largely remained elusive. We identified somatic gene mutations in 25 people with NKTCL by whole-exome sequencing and confirmed them in an extended validation group of 80 people by targeted sequencing. Recurrent mutations were most frequently located in the RNA helicase gene DDX3X (21/105 subjects, 20.0%), tumor suppressors (TP53 and MGA), JAK-STAT-pathway molecules (STAT3 and STAT5B) and epigenetic modifiers (MLL2, ARID1A, EP300 and ASXL3). As compared to wild-type protein, DDX3X mutants exhibited decreased RNA-unwinding activity, loss of suppressive effects on cell-cycle progression in NK cells and transcriptional activation of NF-κB and MAPK pathways. Clinically, patients with DDX3X mutations presented a poor prognosis. Our work thus contributes to the understanding of the disease mechanism of NKTCL.

Homoharringtonine-based induction regimens for patients with de-novo acute myeloid leukaemia: a multicentre, open-label, randomised, controlled phase 3 trial

BACKGROUND Homoharringtonine-based induction regimens have been widely used in China for patients with acute myeloid leukaemia. However, their efficacy has not been tested in a multicentre randomised controlled trial in a large population. We assessed the efficacy and safety of homoharringtonine-based induction treatment for management of newly diagnosed acute myeloid leukaemia. METHODS This open-label, randomised, controlled, phase 3 study was done in 17 institutions in China between September, 2007, and July, 2011. Untreated patients aged 14-59 years with acute myeloid leukaemia were randomly assigned (by a computer-generated allocation schedule without stratification) to receive one of three induction regimens in a 1:1:1 ratio: homoharringtonine 2 mg/m(2) per day on days 1-7, cytarabine 100 mg/m(2) per day on days 1-7, and aclarubicin 20 mg/day on days 1-7 (HAA); homoharringtonine 2 mg/m(2) per day on days 1-7, cytarabine 100 mg/m(2) per day on days 1-7, and daunorubicin 40 mg/m(2) per day on days 1-3 (HAD); or daunorubicin 40-45 mg/m(2) per day on days 1-3 and cytarabine 100 mg/m(2) per day on days 1-7 (DA). Patients in complete remission were offered two cycles of intermediate-dose cytarabine (2 g/m(2) every 12 h on days 1-3). The primary endpoints were the proportion of patients who achieved complete remission after two cycles of induction treatment and event-free survival in the intention-to-treat population. The trial is registered in the Chinese Clinical Trial Register, number ChiCTR-TRC-06000054. FINDINGS We enrolled 620 patients, of whom 609 were included in the intention-to-treat analysis. 150 of 206 patients (73%) in the HAA group achieved complete remission versus 125 of 205 (61%) in the DA group (p=0.0108); 3-year event-free survival was 35.4% (95% CI 28.6-42.2) versus 23.1% (95% CI 17.4-29.3; p=0.0023). 133 of 198 patients (67%) in the HAD group had complete remission (vs DA, p=0·20) and 3-year event-free survival was 32.7% (95% CI 26.1-39.5; vs DA, p=0.08). Adverse events were much the same in all groups, except that more patients in the HAA (12 of 206 [5.8%]) and HAD (13 of 198 [6.6%]) groups died within 30 days than in the DA group (two of 205 [1%]; p=0.0067 vs HAA; p=0.0030 vs HAD). INTERPRETATION A regimen of homoharringtonine, cytarabine, and aclarubicin is a treatment option for young, newly diagnosed patients with acute myeloid leukaemia. FUNDING Chinese National High Tech Programme, Key Special Research Foundation of the Ministry of Science and Technology of China, National Nature Science Foundation of China, National Clinical Key Specialty Construction Project.

Multicenter, Randomized, Open-Label Study Comparing the Efficacy and Safety of Micafungin versus Itraconazole for Prophylaxis of Invasive Fungal Infections in Patients undergoing Hematopoietic Stem Cell Transplant

This multicenter, randomized, open-label phase III study compared the efficacy and safety of micafungin and itraconazole in prophylaxis of invasive fungal infections in neutropenic patients undergoing hematopoietic stem cell transplants in China. Micafungin (50 mg/day i.v.) or itraconazole (5 mg/kg/day p.o.) was administered for ≤42 days. The primary endpoint, treatment success, was defined as no proven, probable, or suspected invasive fungal infection through therapy and the absence of proven or probable invasive fungal infection through the end of 4 weeks after therapy. Noninferiority of micafungin against itraconazole was established if the lower boundary of the 95% confidence interval (CI) was >10%. Of 287 patients, 283 were evaluable for efficacy (136 for micafungin, 147 for itraconazole, intent-to-treat population). Treatment success was documented in 92.6% (126 of 136) of micafungin-treated patients and 94.6% (139 of 147) of itraconazole-treated patients (95% CI, -7.562% to 3.482%; P = .48), indicating noninferiority of micafungin against itraconazole. Results were similar for patients treated per protocol. Whereas the rates of proven or probable invasive fungal infection were numerically higher with micafungin than itraconazole at 4.4% (6 of 136) and 1.4% (2 of 147), rates of suspected invasive fungal infection were similar at 5.9% (8 of 136) and 7.5% (11 of 147), respectively. More patients treated with micafungin than itraconazole completed the study (82.9% versus 67.3%, respectively). Significant differences in incidence of withdrawal due to an adverse event (4.4% versus 21.1%) and drug-related adverse events (8% versus 26.5%) were shown between micafungin and itraconazole (P = .00, chi-square test). Micafungin was as effective as itraconazole in preventing invasive fungal infections in patients with neutropenia. In comparison to itraconazole, treatment tolerance was much better with micafungin.

Genomic Profiling of Adult and Pediatric B-cell Acute Lymphoblastic Leukemia.

Genomic landscapes of 92 adult and 111 pediatric patients with B-cell acute lymphoblastic leukemia (B-ALL) were investigated using next-generation sequencing and copy number alteration analysis. Recurrent gene mutations and fusions were tested in an additional 87 adult and 93 pediatric patients. Among the 29 newly identified in-frame gene fusions, those involving MEF2D and ZNF384 were clinically relevant and were demonstrated to perturb B-cell differentiation, with EP300-ZNF384 inducing leukemia in mice. Eight gene expression subgroups associated with characteristic genetic abnormalities were identified, including leukemia with MEF2D and ZNF384 fusions in two distinct clusters. In subgroup G4 which was characterized by ERG deletion, DUX4-IGH fusion was detected in most cases. This comprehensive dataset allowed us to compare the features of molecular pathogenesis between adult and pediatric B-ALL and to identify signatures possibly related to the inferior outcome of adults to that of children. We found that, besides the known discrepancies in frequencies of prognostic markers, adult patients had more cooperative mutations and greater enrichment for alterations of epigenetic modifiers and genes linked to B-cell development, suggesting difference in the target cells of transformation between adult and pediatric patients and may explain in part the disparity in their responses to treatment.

Phase 3 study of nilotinib vs imatinib in Chinese patients with newly diagnosed chronic myeloid leukemia in chronic phase: ENESTchina

Treatment with a tyrosine kinase inhibitor (TKI) targeting BCR-ABL1 is currently the standard of care for patients with chronic myeloid leukemia (CML) in chronic phase (CML-CP). In this study, we present results of the ENESTchina (Evaluating Nilotinib Efficacy and Safety in Clinical Trials-China) that was conducted to investigate nilotinib 300 mg twice daily vs imatinib 400 mg once daily in a Chinese population. ENESTchina met its primary end point with a statistically significant higher rate of major molecular response (MMR; BCR-ABL1 ≤0.1% on the International Scale) at 12 months in the nilotinib arm vs the imatinib arm (52.2% vs 27.8%; P < .0001), and MMR rates remained higher with nilotinib vs imatinib throughout the follow-up period. Rates of complete cytogenetic response (0% Philadelphia chromosome-positive [Ph+] metaphases by standard cytogenetics) were comparable and ≥80% by 24 months in both arms. The estimated rate of freedom from progression to accelerated phase/blast crisis at 24 months was 95.4% in each arm. The safety profiles of both drugs were similar to those from previous studies. In conclusion, rates of MMR at 12 months were superior with nilotinib vs imatinib in Chinese patients with newly diagnosed Ph+ CML-CP. This trial was registered at www.clinicaltrials.gov as #NCT01275196.

Down-regulation of the PI3K/Akt signaling pathway and induction of apoptosis in CA46 Burkitt lymphoma cells by baicalin

BackgroundBaicalin, a flavone present in Scutellaria baicalensis Georgi, inhibits the growth of human leukemia and myeloma cells through induction of apoptosis.MethodsThe present study was undertaken to ascertain whether cultured Burkitt lymphoma cells undergo apoptosis when treated with baicalin. Growth rates were measured using MTT and colony formation assays, and induction of apoptosis was quantified using Annexin V and DNA fragmentation assays. Mechanisms underlying observed growth suppression were examined using Western blotting.ResultsTreatment of CA46 Burkitt lymphoma cells with baicalin for 48 h markedly decreased the rate of cell proliferation; an IC50 value of 10 μM was obtained. Colony formation was almost fully suppressed at 10 μM baicalin. CA46 cells underwent apoptosis in response to baicalin treatment as evidenced by an increase in the percentage of cells stainable with Annexin V, by increased DNA fragmentation, and by activation of the intrinsic (mitochondrial) pathway for cell death as characterized by increased expression of the cleaved forms of caspase-9, caspase-3, and poly (ADP-ribose) polymerase. Additionally, baicalin was found to down-regulate anti-apoptotic and up-regulate apoptotic components of the phosphatidylinositide-3-kinase (PI3K)/serine/threonine kinase (Akt) signaling pathway.ConclusionsThe concentrations at which baicalin altered expression of components of the PI3K/Akt pathway in CA46 cells were comparable to those that suppressed growth and induced apoptosis, supporting the hypothesis that the observed growth-inhibitory and apoptosis-inducing actions of baicalin in these cells are mediated by down-regulation of this pathway.

Posaconazole vs. fluconazole as invasive fungal infection prophylaxis in China: a multicenter, randomized, open-label study.

BACKGROUND Invasive fungal infection (IFI) is common in neutropenic patients with acute myelogenous leukemia (AML) or myelodysplastic syndrome (MDS). Posaconazole is a broad-spectrum triazole antifungal drug with efficacy in prevention of IFI; however, it has not been previously studied as prophylaxis in a Chinese population. METHODS This multicenter, randomized study in China enrolled AML and MDS patients with persistent chemotherapy-induced neutropenia. Prophylaxis with posaconazole or fluconazole was administered for a maximum of 12 weeks, or until patients recovered from neutropenia and achieved complete remission or an IFI occurred. The primary endpoint was incidence of proven, probable, or possible IFI during treatment. Clinical failure rate, all-cause mortality and time to first systemic antifungal treatment were secondary endpoints. RESULTS Patients were randomized to receive posaconazole (n = 129) or fluconazole (n = 123); 117 patients in each group were included in the statistical analysis. The incidence of proven, probable or possible IFI was 9.4% (11/117) and 22.2% (26/117) in the posaconazole and fluconazole groups, respectively (p = 0.0114). The clinical failure rate was numerically lower in the posaconazole group (37/117 (31.6%; 95%CI: 23.3 - 40.9)) than in the fluconazole group (49/117 (41.88%; 95% CI: 32.8 - 51.4)) (p = 0.168). Patients receiving posaconazole had a later onset of first systematic antifungal treatment than those receiving fluconazole (p = 0.0139). The most common important adverse events were liver function abnormalities (11 patients (8.8%) on posaconazole and 6 (5.0%) on fluconazole (p = 0.221)). CONCLUSIONS Posaconazole demonstrates efficacy as prophylaxis against IFI in high-risk neutropenic Chinese patients and is well tolerated during long-term use (ClinicalTrials. gov number, NCT00811928).

Baicalin Induces Apoptosis in Leukemia HL-60/ADR Cells via Possible Down-regulation of the PI3K/Akt Signaling Pathway

BACKGROUND The effect and possible mechanism of traditional Chinese medicine, baicalin, on the PI3K/ Akt signaling pathway in drug-resistant human myeloid leukemia HL-60/ADR cells have been investigated in this current study. METHODS HL-60/ADR cells were treated by 20, 40, 80 μmol/L baicalin followed by cell cycle analysis at 24h. The mRNA expression level of the apoptosis related gene, Bcl-2 and bad, were measured by RT-PCR on cells treated with 80 μmol/L baicalin at 12, 24 and 48hr. Western blot was performed to detect the changes in the expression of the proteins related to HL-60/ADR cell apoptosis and the signaling pathway before and after baicalin treatment, including Bcl-2, PARP, Bad, Caspase 3, Akt, p-Akt, NF-κB, p-NF-κB, mTOR and p-mTOR. RESULTS Sub-G1 peak of HL-60/ADR cells appeared 24 h after 20 μmol/L baicalin treatment, and the ratio increased as baicalin concentration increased. Cell cycle analysis showed 44.9% G0/G1 phase cells 24 h after baicalin treatment compared to 39.6% in the control group. Cells treated with 80 μmol/L baicalin displayed a trend in decreasing of Bcl-2 mRNA expression over time. Expression level of the Bcl-2 and PARP proteins decreased significantly while that of the PARP, Caspase-3, and Bad proteins gradually increased. No significant difference in Akt expression was observed between treated and the control groups. However, the expression levels of p-Akt, NF-κB, p-NF-κB, mTOR and p-mTOR decreased significantly in a time-dependent manner. CONCLUSIONS We conclude that baicalin may induce HL-60/ADR cell apoptosis through the PI3K/AKT signaling pathway.

Next-generation-sequencing-based risk stratification and identification of new genes involved in structural and sequence variations in near haploid lymphoblastic leukemia†‡

Near haploidy (23–29 chromosomes) is a numerical cytogenetic aberration in childhood acute lymphoblastic leukemia (ALL) associated with particularly poor outcome. In contrast, high hyperdiploidy (51–67 chromosomes) has a favorable prognosis. Correct classification and appropriate risk stratification of near haploidy is frequently hampered by the presence of apparently high hyperdiploid clones that arise by endoreduplication of the original near haploid clone. We evaluated next‐generation‐sequencing (NGS) to distinguish between “high hyperdiploid” leukemic clones of near haploid and true high hyperdiploid origin. Five high hyperdiploid ALL cases and the “high hyperdiploid” cell line MHH‐CALL‐2, derived from a near haploid clone, were tested for uniparental isodisomy. NGS showed that all disomic chromosomes of MHH‐CALL‐2, but none of the patients, were of uniparental origin, thus reliably discriminating these subtypes. Whole‐exome‐ and whole‐genome‐sequencing of MHH‐CALL‐2 revealed homozygous non‐synonymous coding mutations predicted to be deleterious for the protein function of 63 genes, among them known cancer‐associated genes, such as FANCA, NF1, TCF7L2, CARD11, EP400, histone demethylases, and transferases (KDM6B, KDM1A, PRDM11). Only eight of these were also, but heterozygously, mutated in the high hyperdiploid patients. Structural variations in MHH‐CALL‐2 include a homozygous deletion (MTAP/CDKN2A/CDKN2B/ANRIL), a homozygous inversion (NCKAP5), and an unbalanced translocation (FAM189A1). Together, the sequence variations provide MHH‐CALL‐2 with capabilities typically acquired during cancer development, e.g., loss of cell cycle control, enhanced proliferation, lack of DNA repair, cell death evasion, and disturbance of epigenetic gene regulation. Poorer prognosis of near haploid ALL most likely results from full penetrance of a large array of detrimental homozygous mutations.

DIGE-based proteomic analysis identifies nucleophosmin/B23 and nucleolin C23 as over-expressed proteins in relapsed/refractory acute leukemia.

Drug resistance is a challenge in treatment of acute leukemia. To investigate novel protein changes involved in resistance, protein expression profiles between leukemia cell line HL-60 and adriamycin-resistant HL-60 (HL-60/ADR) were compared based on a proteomic approach-2D-DIGE followed by MALDI-TOF/MS. 13 protein spots were identified as up-regulated and 3 down-regulated in HL-60/ADR. Nucleophosmin/B23 (NPM B23) and nucleolin C23 (C23) were selected and verified by western blot, which showed an obvious up-regulation in leukemia cells, especially in 3 resistant leukemia cell lines and in relapsed/refractory patients. To a conclusion, B23 and C23 may be involved in drug resistance and be useful in assessing the prognosis of leukemia.