Chromosomal translocation t(15;17) in human acute promyelocytic leukemia fuses RARα with a novel putative transcription factor, PML

A unique mRNA produced in leukemic cells from a t(15;17) acute promyelocytic leukemia (APL) patient encodes a fusion protein between the retinoic acid receptor a (RARa) and a myeloid gene product called PML. PML contains a cysteine-rich region present in a new family of apparent DNA-binding proteins that includes a regulator of the interleukin-2 receptor gene (Rpt-1) and the recombination-activating gene product (RAG-l). Accordingly, PML may represent a novel transcription factor or recombinase. The aberrant PML-RAR fusion product, while typically retinoic acid responsive, displays both cell type- and promoter-specific differences from the wild-type RARa. Because patients with APL can be Induced into remission with high dose RA therapy, we propose that the nonliganded PML-RAR protein is a new class of dominant negative oncogene product. Treatment with RA would not only relieve this inhibition, but the activated PML-RAR protein may actually promote myelocyte differentiation

Facile synthesis and proposed mechanism of α,ω‐oxetanyl-telechelic poly(3-nitratomethyl-3-methyl oxetane) by an SN2(i) nitrato displacement method in basic media

The synthesis of a novel heterocyclic–telechelic polymer, α,ω-oxetanyl-telechelic poly(3-nitratomethyl-3-methyl oxetane), is described. Infrared spectroscopy (IR), gel permeation chromatography (GPC), and nuclear magnetic resonance (NMR) spectroscopy have been used to confirm the successful synthesis, demonstrating the presence of the telechelic-oxetanyl moieties. Synthesis of the terminal functionalities has been achieved via displacement of nitrato groups, in a manner similar to that employed with other leaving groups such as azido, bromo, and nitro, initiated by nucleophiles. In the present case, displacement occurs on the ends of a nitrato-functionalized polymer driven by the formation of sodium nitrate, which is supported by the polar aprotic solvent N,N-dimethyl formamide. The formation of an alkoxide at the polymer chain ends is favored and allows internal back-biting to the nearest carbon bearing the nitrato group, intrinsically in an SN2(i) reaction, leading to α,ω-oxetanyl functionalization. The telechelic-oxetanyl moieties have the potential to be cross-linked by chemical (e.g., acidic) or radiative (e.g., ultraviolet) curing methods without the use of high temperatures, usually below 100°C. This type of material was designed for future use as a contraband simulant, whereby it would form the predominant constituent of elastomeric composites comprising rubbery polymer with small quantities of solids, typically crystals of contraband substances, such as explosives or narcotics. This method also provides an alternative approach to ring closure and synthesis of heterocycles

Decitabine immunosensitizes human gliomas to NY-ESO-1 specific T lymphocyte targeting through the Fas/Fas Ligand pathway

<p>Abstract</p> <p>Background</p> <p>The lack of effective treatments for gliomas makes them a significant health problem and highlights the need for the development of novel and innovative treatment approaches. Immunotherapy is an appealing strategy because of the potential ability for immune cells to traffic to and destroy infiltrating tumor cells. However, the absence of well-characterized, highly immunogenic tumor-rejection antigens (TRA) in gliomas has limited the implementation of targeted immune-based therapies.</p> <p>Methods</p> <p>We hypothesized that treatment with the demethylating agent, decitabine, would upregulate the expression of TRA on tumor cells, thereby facilitating enhanced surveillance by TRA-specific T cells.</p> <p>Results and Discussion</p> <p>Treatment of human glioma cells with decitabine increased the expression of NY-ESO-1 and other well characterized cancer testes antigens. The upregulation of NY-ESO-1 made these tumors susceptible to NY-ESO-1-specific T-cell recognition and lysis. Interestingly, decitabine treatment of T98 glioma cells also sensitized them to Fas-dependent apoptosis with an agonistic antibody, while a Fas blocking antibody could largely prevent the enhanced functional recognition by NY-ESO-1 specific T cells. Thus, decitabine treatment transformed a non-immunogenic glioma cell into an immunogenic target that was efficiently recognized by NY-ESO-1--specific T cells.</p> <p>Conclusions</p> <p>Such data supports the hypothesis that agents which alter epigenetic cellular processes may "immunosensitize" tumor cells to tumor-specific T cell-mediated lysis.</p

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

The "Retinoic Acid Syndrome" in Acute Promyelocytic Leukemia

OBJECTIVE: To describe a novel complication of therapy with all-trans retinoic acid in patients with acute promyelocytic leukemia. DESIGN: Case series. SETTING: Comprehensive cancer center. PATIENTS: Consecutive patients with a morphologic diagnosis of acute promyelocytic leukemia who underwent remission induction treatment with all-trans retinoic acid, 45 mg/m2 body surface area per day. MEASUREMENTS AND RESULTS: Nine of 35 patients (26%; 95% CI, 9% to 52%) with acute promyelocytic leukemia who were treated with all-trans retinoic acid developed a syndrome consisting primarily of fever and respiratory distress. Additional prominent signs and symptoms included weight gain, lower-extremity edema, pleural or pericardial effusions, and episodic hypotension. The onset of this symptom complex occurred from 2 to 21 days after starting treatment. Three deaths occurred; post-mortem examinations in two patients showed pulmonary interstitial infiltration with maturing myeloid cells. Six other patients survived, each achieving complete remission (five patients with all-trans retinoic acid only; 1 patient with chemotherapy). In six of the nine cases, the onset of the syndrome was preceded by an increase in peripheral blood leukocytes to a level of at least 20 x 10(9) cells/L. Certain therapeutic interventions, including leukapheresis, temporary cessation of therapy with all-trans retinoic acid, and cytotoxic chemotherapy in moderate doses were not useful after respiratory distress was established. However, the administration of high-dose corticosteroid therapy (dexamethasone, 10 mg IV intravenously every 12 hours for 3 or more days) early in the course of the syndrome resulted in prompt symptomatic improvement and full recovery in three of four patients. CONCLUSIONS: The use of all-trans retinoic acid to induce hematologic remission in patients with acute promyelocytic leukemia is associated in some patients with the development of a potentially lethal syndrome that is not uniformly accompanied by peripheral blood leukocytosis. Early recognition of the symptom complex of fever and dyspnea, combined with prompt corticosteroid treatment, may decrease morbidity and mortality associated with this syndrome