Synergy between BRD9- and IKZF3-Targeting as a Therapeutic Strategy for Multiple Myeloma

Progress in the treatment of multiple myeloma (MM) has resulted in improvement in the survival rate. However, there is still a need for more efficacious and tolerated therapies. We and others have shown that bromodomain-containing protein 9 (BRD9), a member of the non-canonical SWI/SNF chromatin remodeling complex, plays a role in MM cell survival, and targeting BRD9 selectively blocks MM cell proliferation and synergizes with IMiDs. We found that synergy in vitro is associated with the downregulation of MYC and Ikaros proteins, including IKZF3, and overexpression of IKZF3 or MYC could partially reverse synergy. RNA-seq analysis revealed synergy to be associated with the suppression of pathways associated with MYC and E2F target genes and pathways, including cell cycle, cell division, and DNA replication. Stimulated pathways included cell adhesion and immune and inflammatory response. Importantly, combining IMiD treatment and BRD9 targeting, which leads to the downregulation of MYC protein and upregulation of CRBN protein, was able to override IMiD resistance of cells exposed to iberdomide in long-term culture. Taken together, our results support the notion that combination therapy based on agents targeting BRD9 and IKZF3, two established dependencies in MM, represents a promising novel therapeutic strategy for MM and IMiD-resistant disease.

[Patient-reported outcomes of locally advanced gastric cancer undergoing robotic versus laparoscopic gastrectomy: a randomized controlled study]

Objective: To compare the patient-reported outcomes and short-term clinical outcomes between robotic-assisted and laparoscopic-assisted radical gastrectomy for locally advanced gastric cancer. Methods: This single-center prospective randomized controlled trial was conducted in the Department of Gastrointestinal Surgery,Affiliated Hospital of Qingdao University from October 2020 to August 2022. Patients with locally advanced gastric cancer who were to undergo radical gastrectomy were selected and randomly divided into two groups according to 1∶1, and received robotic surgery and laparoscopic surgery, respectively. Patient-reported outcomes and short-term clinical outcomes (including postoperative complications, surgical quality and postoperative short-term recovery) were compared between the two groups by t test, Mann-Whitney U test, repeated ANOVA, generalized estimating equation, χ2 test and Fisher's exact test. Results: A total of 237 patients were enrolled for modified intention-to-treat analysis (120 patients in the robotic group, 117 patients in the laparoscopic group). There were 180 males and 59 females, aged (63.0±10.2) years (range: 30 to 85 years). The incidence of postoperative complications was similar between the robotic group and laparoscopic group (16.7% (20/120) vs. 15.4% (18/117), χ2=0.072, P=0.788). The robotic group had higher patient-reported outcomes scores in general health status, emotional, and social domains compared to the laparoscopic group, differences in time effect, intervention effect, and interaction effect were statistically significant (general health status: χ2 value were 275.68, 3.91, 6.38, P value were <0.01, 0.048, 0.041; emotional: χ2 value were 77.79, 6.04, 6.15, P value were <0.01, 0.014, 0.046; social: χ2 value were 148.00, 7.57, 5.98, P value were <0.01, 0.006, 0.048). However, the financial burden of the robotic group was higher, the differences in time effect, intervention effect and interaction effect were statistically significant (χ2 value were 156.24, 4.08, 36.56, P value were<0.01, 0.043,<0.01). Conclusion: Compared to the laparoscopic group, the robotic group could more effectively relieve postoperative negative emotions and improve recovery of social function in patients.

HDAC3 and HDAC8 PROTAC dual degrader reveals roles of histone acetylation in gene regulation

HDAC3 and HDAC8 have critical biological functions and represent highly sought-after therapeutic targets. Because histone deacetylases (HDACs) have a very conserved catalytic domain, developing isozyme-selective inhibitors remains challenging. HDAC3/8 also have deacetylase-independent activity, which cannot be blocked by conventional enzymatic inhibitors. Proteolysis-targeting chimeras (PROTACs) can selectively degrade a target enzyme, abolishing both enzymatic and scaffolding function. Here, we report a novel HDAC3/8 dual degrader YX968 that induces highly potent, rapid, and selective degradation of both HDAC3/8 without triggering pan-HDAC inhibitory effects. Unbiased quantitative proteomic experiments confirmed its high selectivity. HDAC3/8 degradation by YX968 does not induce histone hyperacetylation and broad transcriptomic perturbation. Thus, histone hyperacetylation may be a major factor for altering transcription. YX968 promotes apoptosis and kills cancer cells with a high potency in vitro. YX968 thus represents a new probe for dissecting the complex biological functions of HDAC3/8.

DAXX drives de novo lipogenesis and contributes to tumorigenesis

Cancer cells exhibit elevated lipid synthesis. In breast and other cancer types, genes involved in lipid production are highly upregulated, but the mechanisms that control their expression remain poorly understood. Using integrated transcriptomic, lipidomic, and molecular studies, here we report that DAXX is a regulator of oncogenic lipogenesis. DAXX depletion attenuates, while its overexpression enhances, lipogenic gene expression, lipogenesis, and tumor growth. Mechanistically, DAXX interacts with SREBP1 and SREBP2 and activates SREBP-mediated transcription. DAXX associates with lipogenic gene promoters through SREBPs. Underscoring the critical roles for the DAXX-SREBP interaction for lipogenesis, SREBP2 knockdown attenuates tumor growth in cells with DAXX overexpression, and DAXX mutants unable to bind SREBP1/2 have weakened activity in promoting lipogenesis and tumor growth. Remarkably, a DAXX mutant deficient of SUMO-binding fails to activate SREBP1/2 and lipogenesis due to impaired SREBP binding and chromatin recruitment and is defective of stimulating tumorigenesis. Hence, DAXX's SUMO-binding activity is critical to oncogenic lipogenesis. Notably, a peptide corresponding to DAXX's C-terminal SUMO-interacting motif (SIM2) is cell-membrane permeable, disrupts the DAXX-SREBP1/2 interactions, and inhibits lipogenesis and tumor growth. These results establish DAXX as a regulator of lipogenesis and a potential therapeutic target for cancer therapy.

Anti-SARS-CoV-2 activity of targeted kinase inhibitors: Repurposing clinically available drugs for COVID-19 therapy

Coronavirus disease 2019 (COVID-19) remains a major public health concern, and vaccine unavailability, hesitancy, or failure underscore the need for discovery of efficacious antiviral drug therapies. Numerous approved drugs target protein kinases associated with viral life cycle and symptoms of infection. Repurposing of kinase inhibitors is appealing as they have been vetted for safety and are more accessible for COVID-19 treatment. However, an understanding of drug mechanism is needed to improve our understanding of the factors involved in pathogenesis. We tested the in vitro activity of three kinase inhibitors against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including inhibitors of AXL kinase, a host cell factor that contributes to successful SARS-CoV-2 infection. Using multiple cell-based assays and approaches, gilteritinib, nintedanib, and imatinib were thoroughly evaluated for activity against SARS-CoV-2 variants. Each drug exhibited antiviral activity, but with stark differences in potency, suggesting differences in host dependency for kinase targets. Importantly, for gilteritinib, the amount of compound needed to achieve 90% infection inhibition, at least in part involving blockade of spike protein-mediated viral entry and at concentrations not inducing phospholipidosis (PLD), approached a clinically achievable concentration. Knockout of AXL, a target of gilteritinib and nintedanib, impaired SARS-CoV-2 variant infectivity, supporting a role for AXL in SARS-CoV-2 infection and supporting further investigation of drug-mediated AXL inhibition as a COVID-19 treatment. This study supports further evaluation of AXL-targeting kinase inhibitors as potential antiviral agents and treatments for COVID-19. Additional mechanistic studies are needed to determine underlying differences in virus response.

BRD9 degraders as chemosensitizers in acute leukemia and multiple myeloma

Bromodomain-containing protein 9 (BRD9), an essential component of the SWI/SNF chromatin remodeling complex termed ncBAF, has been established as a therapeutic target in a subset of sarcomas and leukemias. Here, we used novel small molecule inhibitors and degraders along with RNA interference to assess the dependency on BRD9 in the context of diverse hematological malignancies, including acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), and multiple myeloma (MM) model systems. Following depletion of BRD9 protein, AML cells undergo terminal differentiation, whereas apoptosis was more prominent in ALL and MM. RNA-seq analysis of acute leukemia and MM cells revealed both unique and common signaling pathways affected by BRD9 degradation, with common pathways including those associated with regulation of inflammation, cell adhesion, DNA repair and cell cycle progression. Degradation of BRD9 potentiated the effects of several chemotherapeutic agents and targeted therapies against AML, ALL, and MM. Our findings support further development of therapeutic targeting of BRD9, alone or combined with other agents, as a novel strategy for acute leukemias and MM.

POS0286 CAN PATIENTS WITH CONTROLLED RA RECEIVING ANY CLASS OF TARGETED THERAPY WITH METHOTREXATE (MTX) SUSTAIN DISEASE CONTROL AFTER TAPERING MTX? A SYSTEMATIC REVIEW AND META-ANALYSIS

Background

Patients with RA frequently struggle with intolerance of MTX and adherence to MTX remains highly variable. Guidelines conditionally recommend the tapering of MTX before tapering biologic (b)DMARDs, but acknowledge there is an absence of direct evidence. Prior reviews on this topic have focused on tapering of MTX from combination treatment with TNF-inhibitors(i) only1. There have been no updated reviews addressing MTX tapering from other targeted therapies such as IL6-i or JAK-i, nor has there been a systematic review addressing this question.

Objectives

To determine the feasibility of tapering MTX to targeted therapy (bDMARDs or JAKi) alone in patients whose RA is controlled (LDA or remission).

Methods

A systematic literature search combing MeSH terms and keywords was conducted in Medline, Embase and Cochrane Library for studies reporting remission outcomes after tapering MTX from targeted therapies in RA. Non-English and animal studies were excluded. Meta-analyses were conducted using random effects models. Forest and funnel plots were created and heterogeneity was calculated.

Results

Our search identified 5762 citations. After removal of duplicates and screening title/abstract using the COVIDENCE platform, 504 full-text articles were reviewed. Of the 10 articles meeting our inclusion criteria of tapering MTX to monotherapy with a targeted therapy, 3 studies tapered to etanercept, 3 to tocilizumab, 1 to tofacitinib, 1 to certolizumab pegol, 1 to adalimumab and 1 to abatacept monotherapy. Nine studies were RCTs and one was a long-term extension study (LTE) (Table 1). Disease duration was longer in 7 studies (6-11 years) and early in 3 studies (1-9 months). The MTX tapering strategy was gradual in 2 and rapid in 8 studies. Follow-up ranged from 3 -18 months in RCTs, and up to 3 years in the LTE. Studies reporting outcomes up to 1 year after tapering had remission rates ranging 48-76%, but this dropped to 40% in one study reporting 18- month remission outcomes. Our meta-analysis conducted in 2000 RA participants from 10 studies showed that patients who tapered MTX to targeted therapy alone could maintain remission with an overall pooled OR of 0.81 (0.68, 0.97) (Figure 1). There was no heterogeneity among the studies in this group (I2=0.0%, p=0.788). Our funnel plot indicated high precision and potentially less publication bias. No significant difference in remission outcomes between early RA [OR 0.63 (0.33, 1.18)] and established RA [OR 0.84 (0.69, 1.03)] was observed.

Table 1.

Included Studies

Author/ YearnEarly RABaseline treatmentMTX Taper StrategyREM measureFollow-upCurtis 2020253noETA+MTXStopSDAI48 wksEmery 2019147yesABA+MTXStopSDAI48 wksCohen 2019533noTOFA+MTXStopDAS28-CRP48 wksEmery 2019411yesETA+MTXTaper 4 wksDAS2852 wksPablos 2019165noTCZ+MTXStopDAS2828 wksPope 201988noCZP+DMARDStopDAS2818 mosKremer 2018296noTCZ+MTXStopDAS2852 wksEdwards 2017272noTCZ+MTXTaper 24 wksDAS2848 wksKeystone 2016205noETA+MTXStopDAS2818 mosKeystone 2018140yesADA+MTXStopDAS28-CRP3 years

ETA etanercept, ABA abatacept, TOFA tofacitinib, TCZ tocilizumab, CZP certolizumab pegol, ADA adalimumab, REM remission, wk week, mo month, DAS28 Disease Activity Score 28, SDAI Simplified disease activity index.

Conclusion

Patients with controlled RA have a high probability of maintaining disease control after tapering their MTX to targeted therapy alone, up to 18 months. This review may inform patients with controlled disease on any of a range of targeted therapies and MTX, but who are struggling with MTX-related adverse effects and wish to taper it. Longer follow-up studies with attention to radiographic, functional and patient reported outcomes are needed. The possibility of disease worsening must be discussed with the patient in advance with careful follow-up and prompt re-treatment of disease worsening.

References

[1]Subesinghe S, Scott IC. Expert Rev Clin Pharmacol 2015;8:751-60.

Disclosure of Interests

Charis Meng: None declared, Diviya Rajesh: None declared, Deanna Jannat-Khah Shareholder of: AstraZeneca, Cytodyn, Walgreens, Omar Bruce: None declared, Bridget Jivanelli: None declared, Vivian Bykerk Consultant of: Amgen, Bristol Myers Squibb, Genzyme, Gilead, Janssen, Pfizer, Sanofi-Aventis, UCB., Grant/research support from: NIH (NIAID/NIAMS) grant 1UH2AR067691-01 GRANT11652401 and The Cedar Hill Foundation; institution received grants from Bristol Myers Squibb and Amgen;

POS0642 THE PROBABILITY OF SUSTAINING RHEUMATOID ARTHRITIS REMISSION IN PATIENTS TAPERING TARGETED THERAPY USED AS MONOTHERAPY: A SYSTEMATIC REVIEW AND META-ANALYSIS

Background

Up to 30% of RA patients receive monotherapy with biologic (b)DMARDs or JAK inhibitors (i), often due to intolerance of methotrexate (MTX). Monotherapy with IL-6i and JAK-i has been reported to be effective. The EULAR research agenda includes addressing the question of whether tapering of targeted therapy (bDMARDs and JAK-i) used as monotherapy (targeted monotherapy) is possible1.

Objectives

To assess if it is feasible to taper (stop or reduce) targeted monotherapy with controlled RA using existing clinical trial data.

Methods

A systematic review of the literature (2014-2021), cited in Medline, Embase and the Cochrane Library, was performed. Meta-analyses were conducted using random effects models. Forest and funnel plots were created and heterogeneity calculated.

Results

Our search yielded 5762 citations. After de-duplication, screening of titles/abstracts and review of full text articles, we identified 5 studies comparing tapering of targeted monotherapy (TNF-i, tocilizumab (TCZ), abatacept (ABA) and baricitinib) to continuing therapy or other tapering regimens (Table 1). In our meta-analysis of data from 800 patients we observed a trend for lower odds of remission when tapering of targeted monotherapy vs comparator treatment regimen [pooled OR 0.72 (0.35, 1.48)]. In one study comparing stopping monotherapy to continuing MTX, we saw the lowest OR 0.55 (0.20, 1.48). In studies comparing two tapering regimens the pooled OR was higher 2.17 (1.13, 4.16). There was no heterogeneity in the studies which compared tapering to continuing therapy (I2=0.0%, p=0.437) and moderate heterogeneity in the studies that tapered different treatments in both arms (I2=53.7%, p=0.115). Trials using a gradual tapering strategy had a numerically higher odds of remission [OR 2.15 (0.94, 4.92); 3.61(1.85, 7.04)] compared to a trial implementing abrupt withdrawal [OR 1.19 (0.53, 2.68)]. There was a trend for higher remission outcomes in studies of early RA [pooled OR 1.71 (0.72, 4.05)] compared to established RA [pooled OR 1.12 (0.29, 4.27)] (Figure 1). Funnel plots indicate a paucity of studies, and perhaps publication bias.

Table 1.

Included studies.

Author/yearnEarly RAMean Age RangeBaselineTapering strategyComparison arm interventionRemission OutcomeFollow uptreatmentvan Mulligen 2020189No56-57csDMARD + TNFiTaper csDMARD then TNFiTaper in reverse orderDAS44 < 1.624 mosKaneko102No54-58TCZ+MTXStop TCZContinue MTXDAS28 < 2.6104 wks2018vs TCZBijlsma299Yes54TCZ+MTXGradual taper MTX 1st then TCZGradual taper MTXDAS28 < 2.6+SJC≤4104 wks2016vs TCZvs MTXEmery176Yes45-49ABA+MTXStop ABAStop ABA Taper MTX offDAS28-CRP<2.618 mos2015vs ABAvs MTXTakeuchi69Yes48-53Bari 4mgReduce 2mgContinue 4mgCDAI < 2.848 wks2019

ABA abatacept, Bari baricitinib, CDAI Clinical disease activity index, csDMARDS conventional synthetic DMARDs, DAS28 Disease Activity Score 28, MTX methotrexate, SJC swollen joint count, TCZ tocilizumab, wks weeks, mos months.

Conclusion

There are no trials designed to compare tapering targeted monotherapy to continuing it, indicating a significant gap in knowledge in an area of increasing clinical relevance for our patients. There was insufficient evidence to demonstrate the significant effects of tapering targeted monotherapy in RA. Only one study out of 5 compared stopping targeted monotherapy to continuing therapy (MTX), and reported a low OR of remission. Three studies tapered therapy in both arms and one study performed a dose reduction. Our review suggests that stopping targeted monotherapy is unlikely to maintain disease control. More gradual tapering schemes, dose reduction and early treatment of disease may be associated with more successful tapering. More studies are needed to better inform our patients. Currently, we do not recommend stopping targeted monotherapy in RA.

References

[1]Smolen JS, Landewé RBM, Bijlsma JWJ, et al.Ann Rheum Dis 2020;79:685-99.

Disclosure of Interests

Charis Meng: None declared, Diviya Rajesh: None declared, Deanna Jannat-Khah Shareholder of: AstraZeneca, Cytodyn, Walgreens, Omar Bruce: None declared, Bridget Jivanelli: None declared, Vivian Bykerk Consultant of: Amgen, Bristol Myers Squibb, Genzyme, Gilead, Janssen, Pfizer, Sanofi-Aventis, UCB, Grant/research support from: NIH (NIAID/NIAMS) grant 1UH2AR067691-01 GRANT11652401 and The Cedar Hill Foundation; institution received grants from Bristol Myers Squibb and Amgen

[The effects of robotic-assisted versus laparoscopic-assisted radical right hemicolectomy on short-term outcome and long-term prognosis based on propensity score matching]

Objective: To compare the short-term and long-term outcomes between robotic-assisted and laparoscopic-assisted radical right hemicolectomy in patients with adenocarcinoma of the right colon. Methods: Retrospective review of a prospectively collected database identified 288 right colon cancer patients who underwent either robotic-assisted (n=57) or laparoscopic-assisted right hemicolectomy (n=231) between October 2014 and October 2020 at Department of Gastrointestinal Surgery, the Affiliated Hospital of Qingdao University. There were 161 males and 127 females, aging (60.3±12.8) years (range: 17 to 86 years). After propensity score matching as 1∶4 between robotic-assisted and laparoscopic-assisted right hemicolectomy, there were 56 cases in robotic group and 176 cases in laparoscipic group. Perioperative outcomes and overall survival were compared between the two groups using t test, Wilcoxon rank sum test, χ² test, Fisher exact test, Kaplan-Meier method and Log-rank test, respectively. Results: The total operative time was similar between the robotic and laparoscopic group ((206.9±60.7) minutes vs. (219.9±56.3) minutes, t=-1.477, P=0.141). Intraoperative bleeding was less in the robotic group (50 (20) ml vs. 50 (50) ml, Z=-4.591, P<0.01), while the number of lymph nodes retrieved was significantly higher (36.0±10.0 vs. 29.0±10.1, t=4.491, P<0.01). Patients in robotic group experienced significantly shorter hospital stay, shorter time to first flatus, and defecation (t: -2.888, -2.946, -2.328, all P<0.05). Moreover, the overall peri-operative complication rate was similar between robotic and laparoscopic group (17.9% vs. 22.7%, χ²=0.596,P=0.465). The 3-year overall survival were 92.9% and 87.9% respectively and the 3-year disease-free survival rates were 83.1% and 82.6% with no statistical significance between the robotic and laparoscopic group (P>0.05). Conclusions: Compared to laparoscopic-assisted right hemicolectomy, robot-assisted right hemicolectomy could improve some short-term clinical outcomes. The two procedures are both achieving comparable survival.

Stoichioproteomics study of differentially expressed proteins and pathways in head and neck cancer

Hypoxia is a prominent feature of head and neck cancer. However, the oxygen element characteristics of proteins and how they adapt to hypoxia microenvironments of head and neck cancer are still unknown. Human genome sequences and proteins expressed data of head and neck cancer were retrieved from pathology atlas of Human Protein Atlas project. Then compared the oxygen and carbon element contents between proteomes of head and neck cancer and normal oral mucosa-squamous epithelial cells, genome locations, pathways, and functional dissection associated with head and neck cancer were also studied. A total of 902 differentially expressed proteins were observed where the average oxygen content is higher than that of the lowly expressed proteins in head and neck cancer proteins. Further, the average oxygen content of the up regulated proteins was 2.54% higher than other. None of their coding genes were distributed on the Y chromosome. The up regulated proteins were enriched in endocytosis, apoptosis and regulation of actin cytoskeleton. The increased oxygen contents of the highly expressed and the up regulated proteins might be caused by frequent activity of cytoskeleton and adapted to the rapid growth and fast division of the head and neck cancer cells. The oxygen usage bias and key proteins may help us to understand the mechanisms behind head and neck cancer in targeted therapy, which lays a foundation for the application of stoichioproteomics in targeted therapy and provides promise for potential treatments for head and neck cancer.

Influence of cell lysis by Fenton oxidation on cryptic growth in sequencing batch reactor (SBR): Implication of reducing sludge source discharge

The cell lysis-cryptic growth was implemented by Fenton oxidation in sequencing batch reactor. Optimizing sludge lysis condition could maximize the release of nutrients and sludge disintegration degree. After Fenton oxidation, the extracellular polymeric substance was obviously destroyed with the sludge average particle decreased from 64 μm to 36 μm. After 5% of the settled sludge in sequencing batch reactor (SBR) was oxidized by Fenton and then returned to SBR, the mixed liquor suspended solids (MLSS) decreased by 19.3% at the end of 35 days operation, the average mixed liquor volatile suspended solids/mixed liquor suspended solids (MLVSS/MLSS) was promoted by 13.3% during the entire operation. Returning lysed sludge had no significant influence on the organics and nitrogen removal, but the total phosphorus removal was distinctly enhanced by generating FePO4 precipitate. Additionally, returning lysed sludge suppressed nitrifying bacteria and promoted denitrifying bacteria slightly. Consequently, the cell lysis-cryptic growth for reducing sludge source discharge from wastewater biological treatment could be achieved on the premise of ensuring effluent quality.

Small molecule inhibition of deubiquitinating enzyme JOSD1 as a novel targeted therapy for leukemias with mutant JAK2

Mutations in the Janus Kinase 2 (JAK2) gene resulting in constitutive kinase activation represent the most common genetic event in myeloproliferative neoplasms (MPN), a group of diseases involving overproduction of one or more kinds of blood cells, including red cells, white cells, and platelets. JAK2 kinase inhibitors, such as ruxolitinib, provide clinical benefit, but inhibition of wild-type (wt) JAK2 limits their clinical utility due to toxicity to normal cells, and small molecule inhibition of mutated JAK2 kinase activity can lead to drug resistance. Here, we present a strategy to target mutated JAK2 for degradation, using the cell's intracellular degradation machinery, while sparing non-mutated JAK2. We employed a chemical genetics screen, followed by extensive selectivity profiling and genetic studies, to identify the deubiquitinase (DUB), JOSD1, as a novel regulator of mutant JAK2. JOSD1 interacts with and stabilizes JAK2-V617F, and inactivation of the DUB leads to JAK2-V617F protein degradation by increasing its ubiquitination levels, thereby shortening its protein half-life. Moreover, targeting of JOSD1 leads to the death of JAK2-V617F-positive primary acute myeloid leukemia (AML) cells. These studies provide a novel therapeutic approach to achieving selective targeting of mutated JAK2 signaling in MPN.

[Clinical features and prognosis analysis of myelin oligodendrocyte glycoprotein antibody-positive optic neuritis]

Objective: To investigate the clinical characteristics and prognosis of myelin oligodendrocyte glycoprotein (MOG) antibody-positive optic neuritis (ON). Methods: The data of 39 patients with MOG antibody-positive ON in the Department of Neurology of Beijing Tongren Hospital, Capital Medical University from January 1, 2017 to October 31, 2019 were retrospectively collected. There were 25 males and 14 females, aged from 15 to 80 (40±16) years. According to the recurrence, the patients were divided into two groups: the recurrence group (n=12) and the non-recurrence group (n=27). The clinical manifestations, relapse-related factors, magnetic resonance imaging (MRI) manifestations, treatment and prognosis of the two groups were analyzed. Results: A total of 63 eyes were involved, including 30 cases of optic perineuritis (OPN), accounting for 47.6% (30/63). The number of attacks ranged from 1 to 9, among which 12 patients had more than 2 attacks. There were 37 eyes [58.7% (37/63)] with severe visual loss (SVL) at the time of onset, and 7 eyes [11.1% (7/63)] with SVL at the final follow-up. Forty-eight eyes [76.2% (48/63)] had optic disc edema. Forty seven eyes [74.6% (47/63)] showed long-segment disease on optic nerve MRI. One case was complicated with aseptic meningitis and encephalitis. The recurrence group was younger than the non-recurrence group [(28.5±9.8) years vs (43.3±16.4) years, P=0.001]. There were no statistically significant differences between the two groups in gender, bilateral onset, initial visual acuity, final visual acuity, optic disc edema, head and spinal cord lesions, and immunosuppressant (all P>0.05). All patients were treated with methylprednisolone (MP) pulse therapy during the acute attack, and 16 of them were additively treated with immunosuppressive agents; the pain was alleviated or relieved significantly after the application of glucocorticoids. Conclusions: MOG antibody-positive ON often occurred in both eyes at the same time, often manifesting as OPN, often accompanied by optic disc edema, and SVL at the beginning of the disease, but most of the visual recovery was good, might be associated with meningitis and encephalitis. MRI of the optic nerve showed that the lesions often manifested as long-segment lesions. Glucocorticoids could alleviate pain and promote the recovery of visual function.

[Effectiveness and safety of holmium laser therapy via flexible bronchoscopy in 40 children with tracheobronchial tuberculosis]

Objective: To explore the effectiveness and safety of holmium laser treatment via flexible bronchoscopy in children with tracheobronchial tuberculosis (TBTB). Methods: The clinical data of 40 children with TBTB admitted in Qilu Children's Hospital of Shandong University from February 2016 to June 2019 were retrospectively analyzed. According to the treatment approach, they were divided into conventional treatment group (20 cases) and holmium laser treatment group (20 cases). The sex, age, course of disease and lesion location before treatment, and the time till relief of atelectasis and airway obstruction after treatment were compared between the two groups with t test and χ² test. Results: Among the 40 cases, 24 were males and 16 females, and 35 had lymph node fistula (87.5%) and 5 had granulation proliferation (12.5%). There was no statistically significamt difference between the conventional group and laser group in sex (male ratio: 50%（10/20） vs. 75%（15/20）, χ²=2.66, P=0.10), age （(3.2±2.2） years vs. （2.2±1.8） years, t=1.41, P=0.16), course of disease (<1 month ratio: 30%（6/20） vs. 35%（7/20）, χ²=0.11, P=0.73), lesion location (single lesion ratio： 45%（9/20） vs. 60%(12/20), χ²=0.90, P=0.34). The effectiveness was evaluated after 3 months, and the total effective rate were 100% in laser group and 40% in conventional group, the difference was significant (χ²=25.34, P<0.01). No serious adverse events occurred in the two groups during the observational period. Conclusions: Holmium laser treatment via bronchoscopy is an effective way to remove the tuberculosis foci in the trachea, which can reduce the incidence of further related complications, and could be applied in clinical approach.

Residues 315 and 369 in HN Protein Contribute to the Thermostability of Newcastle Disease Virus

Thermostable Newcastle disease virus (NDV) vaccines have been widely used in areas where a “cold-chain” is not reliable. However, the molecular mechanism of NDV thermostability remains poorly understood. In this work, we constructed chimeric viruses by exchanging viral fusion (F) and/or hemagglutinin-neuraminidase (HN) genes between the heat-resistant strain HR09 and thermolabile strain La Sota utilizing a reverse genetic system. The results showed that only chimeras with HN derived from the thermostable virus exhibited a thermostable phenotype at 56°C. The hemagglutinin (HA) and neuraminidase (NA) activities of chimeras with HN derived from the HR09 strain were more thermostable than those containing HN from the La Sota strain. Then, we used molecular dynamics simulation at different temperatures (310 K and 330 K) to measure the HN protein of the La Sota strain. The conformation of an amino acid region (residues 315–375) was observed to fluctuate. Sequence alignment of the HN protein revealed that residues 315, 329, and 369 in the La Sota strain and thermostable strains differed. Whether the three amino acid substitutions affected viral thermostability was investigated. Three mutant viruses based on the thermolabile strain were generated by substituting one, two or three amino acids at positions 315, 369, and 329 in the HN protein. In comparison with the parental virus, the mutant viruses containing mutations S315P and I369V possessed higher thermostablity and HA titers, NA and fusion activities. Taken together, these data indicate that the HN gene of NDV is a major determinant of thermostability, and residues 315 and 369 have important effects on viral thermostability.

Repurposing of Kinase Inhibitors for Treatment of COVID-19

The outbreak of COVID-19, the pandemic disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spurred an intense search for treatments by the scientific community. In the absence of a vaccine, the goal is to target the viral life cycle and alleviate the lung-damaging symptoms of infection, which can be life-threatening. There are numerous protein kinases associated with these processes that can be inhibited by FDA-approved drugs, the repurposing of which presents an alluring option as they have been thoroughly vetted for safety and are more readily available for treatment of patients and testing in clinical trials. Here, we characterize more than 30 approved kinase inhibitors in terms of their antiviral potential, due to their measured potency against key kinases required for viral entry, metabolism, or reproduction. We also highlight inhibitors with potential to reverse pulmonary insufficiency because of their anti-inflammatory activity, cytokine suppression, or antifibrotic activity. Certain agents are projected to be dual-purpose drugs in terms of antiviral activity and alleviation of disease symptoms, however drug combination is also an option for inhibitors with optimal pharmacokinetic properties that allow safe and efficacious co-administration with other drugs, such as antiviral agents, IL-6 blocking agents, or other kinase inhibitors.

[Five cases of optic neuropathy associated with varicella zoster virus infection]

Objective: To investigate the clinical characteristics, treatment and prognosis of optic neuropathy associated with varicella zoster virus (VZV). Methods: Five cases of optic neuropathy associated with VZV infection from Department of Neurology between January 1, 2014 and March 31, 2019 were retrospectively collected. The clinical manifestations, treatment and prognosis were analyzed. Results: There were 7 eyes involved in 5 cases, 3 cases (3/5) involved only one eye, and 2 cases (2/5) involved both optic nerves. During the follow-up time, no recurrence was found. Severe visual impairment occurred in 4 eyes (4/7) and non-severe visual impairment in 3 eyes (3/7). Visual acuity improved significantly in 1 eye (1/7), turned better in 2 eyes (2/7), and remained unchanged in 4 eyes (4/7). In acute phase, abnormal signals of optic nerve and/or sheath were observed on MR images. Case 3 received antiviral and hormone therapy on the second day after the onset of the disease, and the visual acuity recovered well; the other 4 cases had poor prognosis. Conclusions: Head and face VZV infection can cause serious optic neuropathy, leading to severe visual dysfunction, and poor prognosis, but recurrence is rare. Early intravenous administration of antiviral drugs (acyclovir is the best) and hormones are recommended for VZV infection in this area. It is best to use drugs within 72 hours in order to avoid and reduce secondary optic neuropathy as far as possible.

Correction: Evaluation of ERK as a therapeutic target in acute myelogenous leukemia

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Comprehensive evaluation of the effects of climate change and land use and land cover change variables on runoff and sediment discharge

Climate change and various human activities have resulted in noticeable changes in watershed hydrological and soil erosion regimes. In this study, a comprehensive investigation was conducted to distinguish between the effects of climate variables and those of land use and land cover change (LUCC) variables on runoff and sediment discharge in the Zhenjiangguan watershed, which is located at the headstream basin of the Minjiang River in southwest China. Statistical analysis results revealed significant and slight decreasing trends in runoff and sediment discharge, respectively. Abrupt changes occurred in 1974 and 1995, which divided the entire time series into a decrease-increase-decrease tendency pattern; this pattern was the response to climate changes and the Reforestation and Returning Farmland to Forest project in China. In addition, redundancy analysis was used for partition statistical analyses, and the contributions of climate change and LUCC to runoff and sediment discharge were at the ratio of 4:1. Since 1990, the effect of LUCC has increased notably and its relationship with hydrological variables changed from positive to negative in approximately 1995. Finally, simulations performed using the distributed Basic Pollution Calculation Center (BPCC) model confirmed that climate and LUCC variables reduced the runoff depth and sediment load between 1980 and 2003. The contributions of climate fluctuation and LUCC to runoff depth were at the ratio of 5:1, and those to sediment load were at the ratio of 3:1, which exhibited the dominant role of climate change and the high sensitivity of sediment load to human interference. Overall, the results of distributed hydrological modeling were consistent with those of statistical analyses. The results provided detailed information and explained the mechanics underlying hydrological processes and soil erosion.

Effects of the multi-kinase inhibitor midostaurin in combination with chemotherapy in models of acute myeloid leukaemia

Recently, several targeted agents have been developed for specific subsets of patients with acute myeloid leukaemia (AML), including midostaurin, the first FDA‐approved FLT3 inhibitor for newly diagnosed patients with FLT3 mutations. However, in the initial Phase I/II clinical trials, some patients without FLT3 mutations had transient responses to midostaurin, suggesting that this multi‐targeted kinase inhibitor might benefit AML patients more broadly. Here, we demonstrate submicromolar efficacy of midostaurin in vitro and efficacy in vivo against wild‐type (wt) FLT3‐expressing AML cell lines and primary cells, and we compare its effectiveness with that of other FLT3 inhibitors currently in clinical trials. Midostaurin was found to synergize with standard chemotherapeutic drugs and some targeted agents against AML cells without mutations in FLT3. The mechanism may involve, in part, the unique kinase profile of midostaurin that includes proteins implicated in AML transformation, such as SYK or KIT, or inhibition of ERK pathway or proviability signalling. Our findings support further investigation of midostaurin as a chemosensitizing agent in AML patients without FLT3 mutations.

The combination of FLT3 and SYK kinase inhibitors is toxic to leukaemia cells with CBL mutations

Mutations in the E3 ubiquitin ligase CBL, found in several myeloid neoplasms, lead to decreased ubiquitin ligase activity. In murine systems, these mutations are associated with cytokine-independent proliferation, thought to result from the activation of hematopoietic growth receptors, including FLT3 and KIT. Using cell lines and primary patient cells, we compared the activity of a panel of FLT3 inhibitors currently being used or tested in AML patients and also evaluated the effects of inhibition of the non-receptor tyrosine kinase, SYK. We show that FLT3 inhibitors ranging from promiscuous to highly targeted are potent inhibitors of growth of leukaemia cells expressing mutant CBL in vitro, and we demonstrate in vivo efficacy of midostaurin using mouse models of mutant CBL. Potentiation of effects of targeted FLT3 inhibition by SYK inhibition has been demonstrated in models of mutant FLT3-positive AML and AML characterized by hyperactivated SYK. Here, we show that targeted SYK inhibition similarly enhances the effects of midostaurin and other FLT3 inhibitors against mutant CBL-positive leukaemia. Taken together, our results support the notion that mutant CBL-expressing myeloid leukaemias are highly sensitive to available FLT3 inhibitors and that this effect can be significantly augmented by optimum inhibition of SYK kinase.

Molecular cloning and functional characterisation of duck (Anas platyrhynchos) tumour necrosis factor receptor-associated factor 3

1. Tumour necrosis factor receptor-associated factor 3 (TRAF3) is a key regulator of innate immunity and acquired immunity, and has a salient anti-viral role. 2. In this experiment, the duck TRAF3 (DuTRAF3) gene was cloned according to the Anas platyrhynchos TRAF3 sequence to explore its function. The TRAF3 open reading frame contains 1704 bp that encode a protein of 567 amino acids, which contain a RING finger domain, two zinc finger motifs, a coiled-coil region, and a MATH domain. 3. Reverse transcription-polymerase chain reaction showed that DuTRAF3 was expressed in all the examined tissues, with a comparatively higher expression in the spleen and brain tissues. 4. In HEK293T cells, DuTRAF3 overexpression resulted in a significantly increased NF-κB activity and interferon (IFN)-β promoter activation. 5. Following resiquimod (R848) and poly(I:C) stimulation of duck peripheral blood mononuclear cells (PBMCs), the expressions of TRAF3 and IFN-β were significantly upregulated; in addition, following R848 stimulation, the mRNA levels of IL-6, IL-8 and IL-10 were also significantly upregulated. After infection with the Newcastle Disease Virus LaSota vaccine strain, the mRNA levels of IL-6 and IL-10 were significantly upregulated, while that of TRAF3 was downregulated. 6. These results suggest that DuTRAF3 has an important role to play in innate antiviral immune responses.

[Value of serum HBV RNA in HBeAg-negative patients with chronic hepatitis B]

Objective: To analyze serum HBV-RNA levels in patients with chronic hepatitis B whose serum HBV-DNA has dropped to undetected levels after treatment with entecavir, and to explore the correlation between HBV-RNA level and liver biochemical parameters, which lay the research foundation for the clinical significance of new serological marker HBV-RNA. Methods: HBeAg negatively detected 107 cases with chronic hepatitis B whose serum HBV-DNA test results were lower than detection level for six consecutive months after receiving standard nucleoside therapy for more than 12 months were included. HBV-RNA level was detected by Perkin-Elmer reagent. HBV-DNA level was detected by Roche Cobas. Hitachi automatic biochemical analyzer was used to detect ALT and AST. Architect chemiluminescence analyzer was used to detect HBsAg, HBeAg, anti-HBe and anti-HBc. RStudio software was performed to analyze the correlation between HBV-RNA level and liver biochemical parameters. Logistic regression was used to analyze the independent factors influencing HBV-RNA level. Results: The positive detection rate of serum HBV-RNA in patients with chronic hepatitis B whose serum HBV-DNA had dropped to undetected levels after ETV treatment was 22.43%. HBsAg, ALT and AST levels in HBV-RNA positive group were slightly higher than HBV-RNA negative group, while anti-HBc levels were slightly higher in HBV-RNA negative group. There was no difference in the level of anti-HBe between the HBV-RNA negative and the positive group. Logistic regression analysis showed that anti-HBc was an independent factor influencing the level of HBV-RNA detection (P = 0.021). Conclusion: HBV-RNA can be detected in some patients with chronic hepatitis B whose serum HBV-DNA level has dropped to undetected levels after ETV treatment. Serum HBV-RNA only comes from the direct transcription of cccDNA, so it is better than HBV-DNA and HBsAg to reflect cccDNA level or activity. Anti-HBc, as an independent factor influencing the level of HBV-RNA, may be used in combination as a new marker to predict the efficacy of antiviral therapy.

[Clinical analysis of 36 cases of idiopathic intracranial hypertension complicated with iron deficiency anemia]

Objective: To investigate the clinical features, imaging findings and prognosis of idiopathic intracranial hypertension (IIH) patients complicated with iron deficiency anemia (IDA). Methods: A total of 307 cases of IIH patients hospitalized in Beijing Tongren Hospital were retrospectively screened between January 1, 2011 and February 28, 2018. There were 49 anemia cases (15.96%) and 45 IDA cases (14.66%), respectively. Finally, 36 IDA patients were enrolled. The clinical characteristics, imaging findings, treatment and prognosis of these patients were analyzed. Results: IIH combined with IDA was more common in women of childbearing age (34/36). There were 30 obese and overweight cases (83.33%), with multiple subacute or chronic course of disease. The visual symptoms in the early IIH patients were first diagnosed in the Department of Ophthalmology. The first symptom was headache with/without visual symptoms (27 cases (75%)). Head MRI detected empty sella or partial empty sella, and 2 cases of venous sinus thrombosis were found in DSA examination. Of the 34 female patients, 24 had simple menometrorrhagia or menstrual disorder. All patients were given methyl acetate to reduce the intracranial pressure and iron therapy. Five patients received low molecular weight heparin-warfarin sequential treatment, 5 cases underwent gynecologic surgery and 2 male cases received hemorrhoid operation. There were 7 cases underwent lumbar cisterna-peritoneal shunt for visual impairment. During the follow-up, intracranial pressure decreased and visual function of patients improved significantly. Conclusions: IIH is frequently found in obese or overweight women at childbearing age and IDA may be an important cause of IIH. IIH can cause serious irreversible visual impairment. Therefore, early identification and active treatment should be performed. Correction of anemia can significantly improve the clinical symptoms of IIH. Operation should be employed for IIH patients with poor visual function or rapid progress, in order to reduce intracranial pressure and improve prognosis as soon as possible.

Hepatitis B Virus cccDNA in Hepatocellular Carcinoma Tissue Increases the Risk of Recurrence After Liver Transplantation

BACKGROUND

High hepatitis B virus (HBV) DNA level is strongly associated with hepatocellular carcinoma (HCC) development in chronic HBV infection. The aim of this study was to investigate the association between intrahepatic HBV DNA titer and post-liver transplantation (LT) prognosis for HBV-related HCC (HBV-HCC) patients.

METHODS

A total of 60 patients with HBV-HCC who underwent LT were retrospectively studied. Using quantitative TaqMan fluorescent real-time polymerase chain reaction assay, HBV total DNA (tDNA) and covalently closed circular DNA (cccDNA) were both quantified in tumor tissue (TT) and adjacent non-tumor tissue (ANTT) from the explanted liver.

RESULTS

The loads of tDNA and cccDNA in ANTT were associated with serum HBV DNA levels. Multivariate analysis showed that the presence of vascular invasion and cccDNA in TT were independent risk factors for tumor recurrence. The group of patients with cccDNA titers ≥31og_l0 copies/μg in TT had significantly higher cumulative recurrence rates than those with <31og_l0 copies/μg group. The cccDNA titers predicted the tumor recurrence with an area under the receiver operating characteristic curve of 0.664.

CONCLUSIONS

Our findings would assist the clinical implementation of a more personalized therapy for tumor recurrence control and improve the prognosis of HBV-HCC patients.

Comparison of effects of midostaurin, crenolanib, quizartinib, gilteritinib, sorafenib and BLU-285 on oncogenic mutants of KIT, CBL and FLT3 in haematological malignancies

Mutations in two type-3 receptor tyrosine kinases (RTKs), KIT and FLT3, are common in both acute myeloid leukaemia (AML) and systemic mastocytosis (SM) and lead to hyperactivation of key signalling pathways. A large number of tyrosine kinase inhibitors (TKIs) have been developed that target either FLT3 or KIT and significant clinical benefit has been demonstrated in multiple clinical trials. Given the structural similarity of FLT3 and KIT, it is not surprising that some of these TKIs inhibit both of these receptors. This is typified by midostaurin, which has been approved by the US Food and Drug Administration for mutant FLT3-positive AML and for KIT D816V-positive SM. Here, we compare the in vitro activities of the clinically available FLT3 and KIT inhibitors with those of midostaurin against a panel of cells expressing a variety of oncogenic FLT3 or KIT receptors, including wild-type (wt) FLT3, FLT3-internal tandem duplication (ITD), FLT3 D835Y, the resistance mutant FLT3-ITD+ F691L, KIT D816V, and KIT N822K. We also examined the effects of these inhibitors in vitro and in vivo on cells expressing mutations in c-CBL found in AML that result in hypersensitization of RTKs, such as FLT3 and KIT. The results show a wide spectrum of activity of these various mutations to these clinically available TKIs.

Phenotypic analysis of atopic dermatitis in children aged 1-12 months: elaboration of novel diagnostic criteria for infants in China and estimation of prevalence

BACKGROUND

Atopic dermatitis (AD) is the most common skin disorder in infancy. However, the diagnosis and definite significance of infantile AD remains a debated issue.

OBJECTIVE

To analyse the phenotypes of AD in infancy, to establish diagnostic criteria and to estimate the prevalence of this condition in China.

METHODS

This is a multicentric study, in which 12 locations were chosen from different metropolitan areas of China. Following careful and complete history-taking and skin examination, the definite diagnosis of AD was made and the severity based on the SCORAD index was determined by local experienced dermatologists. Based on the detailed phenotyping, the major and representative clinical features of infantile AD were selected to establish the diagnostic criteria and evaluate their diagnostic efficacy.

RESULTS

A total of 5967 infants were included in this study. The overall point prevalence of AD was 30.48%. The infantile AD developed as early as at the second month of life, and its incidence peaked in the third month of life at 40.81%. The proportion of mild, moderate and severe AD was 67.40%, 30.57% and 2.03%, respectively. The most commonly seen manifestations in the infantile AD were facial dermatitis (72.07%), xerosis (42.72%) and scalp dermatitis (27.93%). We established the novel diagnostic criteria of infants, which included: (i) onset after 2 weeks of birth; (ii) pruritus and/or irritability and sleeplessness comparable with lesions; and (iii) all two items above with one of the following items can reach a diagnosis of AD: (i) eczematous lesions distributed on cheeks and/or scalp and/or extensor limbs, and (ii) eczematous lesions on any other parts of body accompanied by xerosis.

CONCLUSIONS

In China, the prevalence of AD in infancy is 30.48% according to clinical diagnosis of dermatologists. The novel Chinese diagnostic criteria for AD in infants show a higher sensitivity and comparable specificity.

[Clinical and immunological characteristics and predicted factors of vision outcome in patients with acute severe bilateral optic neuritis]

Objective: To analyze the clinical and immunological characteristics of acute severe bilateral optic neuritis, and to explore the predictive factors of vision outcome and relapse so as to save visual function and avoid or alleviate vision disability. Methods: Forty-eight inpatients confirmed with acute severe bilateral optic neuritis from January 2013 to June 2015 were included and followed up. The clinical features, immunological findings, optic nerve imaging, visual function outcome and predictors of relapse were statistically analyzed. Results: Acute severe bilateral optic neuritis accounted for 7.3% of the total number of optic neuritis in the same period. There were 35 cases (72.9%) with monophasic course, and 13 cases (27.1%) with recurrence or other central nervous system involvement during the follow-up period; 11 (22.9%) in 48 patients with positive AQP4-IgG; AQP4-IgG-positive patients had a higher recurrence rate (P<0.001) and poorer visual function prognosis (P=0.034) than antibody-negative patients; the baseline visual acuity (P=0.004), early treatment response (P=0.012) and number of involved optic nerve segments (P=0.016) were associated with end point visual function. Positive AQP4-IgG(OR 13.486, 95% CI 1.971-16.263)and combining with other autoimmune antibodies (OR 5.591, 95% CI 1.502-15.621)were independently associated with relapse. Conclusions: Acute severe bilateral optic neuritis is not unusual and may cause blindness or visual disability. The positive rate of AQP4-IgG and the recurrence rate of the disease are low in our study. The necessity for long-term immunotherapy requires individual consideration. The baseline visual acuity, involved segment number of optic nerve and response to early treatment are associated with prognosis of visual function. Patients with AQP4-IgG positive and other autoimmune antibodies are easy to relapse. Whether the antibody-negative bilateral optic neuritis is a heterogeneous disease and the relationship with classic NMO or NMOSD deserve further research.

[Clinical features of chronic relapsing inflammatory optic neuropathy]

Objective: To explore the clinical characteristics and prognosis of chronic relapsing inflammatory optic neuropathy (CRION). Methods: A retrospective analysis was conducted. Clinical features, disease course, prognosis and magnetic resonance imaging (MRI) of patients with CRION who were admitted to Department of Neurology between 2014 and 2016 were reviewed and analyzed. Results: Totally, there were 27 patients (10 males and 17 females), with an age range of 17-59 years. The disease duration was between 40 days and 8 years. There were 2 to 9 CRION episodes. The mean frequency of CRION episodes was 3.30±1.56. The outcome of visual acuity showed that the more episodes frequency was, the worse outcome became. There was 25 abnormal optic nerve signals in MRI. And in 22 cases, the abnormal signals were in intraorbital segment or inner pipe section. The antinuclear antibodies (ANA) titers were elevated in 5 patients. Five cases relapsed during reduction or withdrawal of steroids, but steroids was not added in time. The final outcome of these 5 patients was poor. Conclusions: CRION was more common in female than male patients. Most patients were companied by pain, and the lesions were more common in the intraorbital segment of optic nerve. The more episode frequency was, the worse prognosis became. If a relapse happened, steroids or other immunosuppressive agents should be used.

Reduced Co3O4 nanowires with abundant oxygen vacancies as an efficient free-standing cathode for Li–O2 batteries

The reduced Co₃O₄ cathode with abundant oxygen vacancies significantly improves the battery's cycling stability.

Characterization of midostaurin as a dual inhibitor of FLT3 and SYK and potentiation of FLT3 inhibition against FLT3-ITD-driven leukemia harboring activated SYK kinase

Oncogenic FLT3 kinase is a clinically validated target in acute myeloid leukemia (AML), and both multi-targeted and selective FLT3 inhibitors have been developed. Spleen tyrosine kinase (SYK) has been shown to be activated and increased in FLT3-ITD-positive AML patients, and has further been shown to be critical for transformation and maintenance of the leukemic clone in these patients. Further, over-expression of constitutively activated SYK causes resistance to highly selective FLT3 tyrosine kinase inhibitors (TKI). Up to now, the activity of the multi-targeted FLT3 inhibitor, midostaurin, against cells expressing activated SYK has not been explored in the context of leukemia, although SYK has been identified as a target of midostaurin in systemic mastocytosis. We compared the ability of midostaurin to inhibit activated SYK in mutant FLT3-positive AML cells with that of inhibitors displaying dual SYK/FLT3 inhibition, targeted SYK inhibition, and targeted FLT3 inhibition. Our findings suggest that dual FLT3/SYK inhibitors and FLT3-targeted drugs potently kill oncogenic FLT3-transformed cells, while SYK-targeted small molecule inhibition displays minimal activity. However, midostaurin and other dual FLT3/SYK inhibitors display superior anti-proliferative activity when compared to targeted FLT3 inhibitors, such as crenolanib and quizartinib, against cells co-expressing FLT3-ITD and constitutively activated SYK-TEL. Interestingly, additional SYK suppression potentiated the effects of dual FLT3/SYK inhibitors and targeted FLT3 inhibitors against FLT3-ITD-driven leukemia, both in the absence and presence of activated SYK. Taken together, our findings have important implications for the design of drug combination studies in mutant FLT3-positive patients and for the design of future generations of FLT3 inhibitors.

[Clinical and genetic analysis of a family with Joubert syndrome type 10 caused by OFD1 gene mutation]

Objective: To investigate the genetic cause for a family with multiorgan dysplasia and "molar tooth sign" on MRI image. Method: The patient, a 3 months and 21 days old boy, was clinically examined and the medical history of his family was collected. Next generation sequencing was performed to analyze his clinical and genetic causes. Result: Clinical manifestation of the child displayed multiorgan dysplasia, such as six finger deformity, short limbs, coloboma of optic disc and choroid, situs inversus.Cranial MRI showed "molar tooth sign" . The gene sequencing confirmed that the child carried a de novo deletion of c. 2843_2844 delAA in OFD1 gene. Conclusion: The child has typical clinical features of Joubert syndrome, such as MRI "molar syndrome" , developmental abnormalities of ocular tissue and limb, visceral inversion, and so on.The OFD1 gene had a novel deletion mutation through gene detection. Combined clinical features with gene detection, it was clear that the child was a rare case of Joubert syndrome type 10 which was the first case of Joubert syndrome caused by OFD1 gene mutation in China.

The cancer-associated CTCFL/BORIS protein targets multiple classes of genomic repeats, with a distinct binding and functional preference for humanoid-specific SVA transposable elements

Background

A common aberration in cancer is the activation of germline-specific proteins. The DNA-binding proteins among them could generate novel chromatin states, not found in normal cells. The germline-specific transcription factor BORIS/CTCFL, a paralog of chromatin architecture protein CTCF, is often erroneously activated in cancers and rewires the epigenome for the germline-like transcription program. Another common feature of malignancies is the changed expression and epigenetic states of genomic repeats, which could alter the transcription of neighboring genes and cause somatic mutations upon transposition. The role of BORIS in transposable elements and other repeats has never been assessed.

Results

The investigation of BORIS and CTCF binding to DNA repeats in the K562 cancer cells dependent on BORIS for self-renewal by ChIP-chip and ChIP-seq revealed three classes of occupancy by these proteins: elements cohabited by BORIS and CTCF, CTCF-only bound, or BORIS-only bound. The CTCF-only enrichment is characteristic for evolutionary old and inactive repeat classes, while BORIS and CTCF co-binding predominately occurs at uncharacterized tandem repeats. These repeats form staggered cluster binding sites, which are a prerequisite for CTCF and BORIS co-binding. At the same time, BORIS preferentially occupies a specific subset of the evolutionary young, transcribed, and mobile genomic repeat family, SVA. Unlike CTCF, BORIS prominently binds to the VNTR region of the SVA repeats in vivo. This suggests a role of BORIS in SVA expression regulation. RNA-seq analysis indicates that BORIS largely serves as a repressor of SVA expression, alongside DNA and histone methylation, with the exception of promoter capture by SVA.

Conclusions

Thus, BORIS directly binds to, and regulates SVA repeats, which are essentially movable CpG islands, via clusters of BORIS binding sites. This finding uncovers a new function of the global germline-specific transcriptional regulator BORIS in regulating and repressing the newest class of transposable elements that are actively transposed in human genome when activated. This function of BORIS in cancer cells is likely a reflection of its roles in the germline.

Electronic supplementary material

The online version of this article (doi:10.1186/s13072-016-0084-2) contains supplementary material, which is available to authorized users.

Kinetic analysis of RNA editing of Newcastle disease virus P gene in the early period of infection

As a paramyxovirus, Newcastle disease virus (NDV) has the ability to edit its P (phosphoprotein) gene to synthesize three kinds of viral protein (P, V and W). It is technically very difficult to differentiate P, V and W mRNAs, and little was known about NDV regulation of RNA-editing frequency. To investigate the rules of NDV RNA editing, the ratio of the P gene-derived transcripts (P, V and W) was determined by sequencing at different time points post-infection. The results showed unstable ratio of V and W mRNA at different time points, and the frequency of NDV editing was significantly increased at the early period of infection (P 

KEYWORDS

Newcastle disease virus; phosphoprotein; RNA editing; G insertion.

HCV NS3Ag: a reliable and clinically useful predictor of antiviral outcomes in genotype 1b hepatitis C virus-infected patients

Since hepatitis C virus (HCV) non-structural 3 (NS3) protease inhibitor (PI) combined with pegylated interferon/ribavirin (PR) has been approved for chronic HCV genotype (GT) 1b infection, a reliable and clinically useful predictor combining with serum HCV RNA to predict early virologic response, breakthrough, and relapse is important during HCV antiviral treatment. We evaluated the role of HCV NS3 antigen (HCV NS3Ag) on the prediction of virologic response in patients with HCV GT1b during PR or PR/simeprevir (triple) therapy. Three hundred patients were recruited, and HCV RNA and HCV NS3Ag were tested at baseline and weeks 2, 4, 12, 24, 48, and 72. NS3Ag and HCV RNA were significantly related (r(2) = 0.67) in the whole patient selection. The kinetic pattern of HCV RNA and HCV NS3Ag during triple treatment was similar. HCV NS3Ag levels in the triple group closely followed those of HCV RNA; the r(2) values were 0.756 (baseline), 0.837 (2 weeks), 0.989 (4 weeks), and 0.993 (12 weeks), respectively. For patients treated with PR, the positive and negative predictive values (PPVs and NPVs) for viral response were 96.31 % and 67.19 %, respectively, at week 4 by using the decrease of NS3Ag (dHCV NS3Ag) combined with HCV RNA. At week 12, the PPV was similar at 94.16 %, while the NPV reached 87.26 %. The PPV and NPV for the prediction of relapse and breakthrough were 90.6 % and 76.7 %, respectively. HCV NS3Ag is a valuable marker and could be a supplementary predictor of HCV RNA for the prediction of antiviral response, breakthrough, or relapse during HCV antiviral treatment.

Extensive and interrelated subcortical white and gray matter alterations in preterm-born adults

Preterm birth is a leading cause for impaired neurocognitive development with an increased risk for persistent cognitive deficits in adulthood. In newborns, preterm birth is associated with interrelated white matter (WM) alterations and deep gray matter (GM) loss; however, little is known about the persistence and relevance of these subcortical brain changes. We tested the hypothesis that the pattern of correspondent subcortical WM and GM changes is present in preterm-born adults and has a brain-injury-like nature, i.e., it predicts lowered general cognitive performance. Eighty-five preterm-born and 69 matched term-born adults were assessed by diffusion- and T1-weighted MRI and cognitive testing. Main outcome measures were fractional anisotropy of water diffusion for WM property, GM volume for GM property, and full-scale IQ for cognitive performance. In preterm-born adults, reduced fractional anisotropy was widely distributed ranging from cerebellum to brainstem to hemispheres. GM volume was reduced in the thalamus, striatum, temporal cortices, and increased in the cingulate cortices. Fractional anisotropy reductions were specifically associated with GM loss in thalamus and striatum, with correlation patterns for both regions extensively overlapping in the WM of brainstem and hemispheres. For overlap regions, fractional anisotropy was positively related with both gestational age and full-scale IQ. Results provide evidence for extensive, interrelated, and adverse WM and GM subcortical changes in preterm-born adults. Data suggest persistent brain-injury-like changes of subcortical-cortical connectivity after preterm delivery.