Extended treatment with MY-NEOVAX, personalized neoantigen-enhanced oncolytic viruses, for two end-stage cancer patients.

Neoantigen vaccines involving multi-peptides and poly-epitope-encoding RNA or DNA have undergone early phase clinical testing with modest reported antitumor effects [ 1]. The less-than-expected activity of these neoantigenic vaccines may correspond with the development of immune escape mechanisms. One permutation on neoantigen vaccines, which may counter or prevent these adaptive immune escape mechanisms, are 'personalized' oncolytic viruses that encode one or more tumor-specific transgenes. Herein, positive therapeutic effects for MY-NEOVAX™, personalized neoantigen-enhanced oncolytic adenoviruses, are described for two heavily pretreated end-stage patients, one with high-grade metastatic neuroendocrine carcinoma of the pancreas and the other with colorectal cancer metastatic to the brain, liver and lungs. To date, treatment benefit has exceeded 12 months without dose-limiting toxicities or related serious adverse events and with documented radiologic stabilization and improved performance status

Identification of a very long chain polyunsaturated fatty acid Δ4-desaturase from the microalga Pavlova lutheri11The sequence reported in this paper has been submitted to GenBank database under the accession number AY332747.

AbstractPavlova lutheri, a marine microalga, is rich in the very long chain polyunsaturated fatty acids (VLCPUFAs) eicosapentaenoic (20:5n-3) and docosahexaenoic (22:6n-3) acids. Using an expressed sequence tag approach, we isolated a cDNA designated Pldes1, and encoding an amino acid sequence showing high similarity with polyunsaturated fatty acid front-end desaturases. Heterologous expression in yeast demonstrated that PlDES1 desaturated 22:5n-3 and 22:4n-6 into 22:6n-3 and 22:5n-6 respectively, and was equally active on both substrates. Thus, PlDES1 is a novel VLCPUFA Δ4-desaturase. Pldes1 expression is four-fold higher during the mid-exponential phase of growth compared to late exponential and stationary phases

Engineering a catabolic pathway in plants for the degradation of 1,2-dichloroethane

Plants are increasingly being employed to clean up environmental pollutants such as heavy metals; however, a major limitation of phytoremediation is the inability of plants to mineralize most organic pollutants. A key component of organic pollutants is halogenated aliphatic compounds that include 1,2-dichloroethane (1,2-DCA). Although plants lack the enzymatic activity required to metabolize this compound, two bacterial enzymes, haloalkane dehalogenase (DhlA) and haloacid dehalogenase (DhlB) from the bacterium Xanthobacter autotrophicus GJ10, have the ability to dehalogenate a range of halogenated aliphatics, including 1,2-DCA. We have engineered the dhlA and dhlB genes into tobacco (Nicotiana tabacum ‘Xanthi’) plants and used 1,2-DCA as a model substrate to demonstrate the ability of the transgenic tobacco to remediate a range of halogenated, aliphatic hydrocarbons. DhlA converts 1,2-DCA to 2-chloroethanol, which is then metabolized to the phytotoxic 2-chloroacetaldehyde, then chloroacetic acid, by endogenous plant alcohol dehydrogenase and aldehyde dehydrogenase activities, respectively. Chloroacetic acid is dehalogenated by DhlB to produce the glyoxylate cycle intermediate glycolate. Plants expressing only DhlA produced phytotoxic levels of chlorinated intermediates and died, while plants expressing DhlA together with DhlB thrived at levels of 1,2-DCA that were toxic to DhlA-expressing plants. This represents a significant advance in the development of a low-cost phytoremediation approach toward the clean-up of halogenated organic pollutants from contaminated soil and groundwater

Toxicity of unsaturated fatty acids to the biohydrogenating ruminal bacterium, Butyrivibrio fibrisolvens

Peer reviewedPublisher PD

PRMT7 regulates RNA-binding capacity and protein stability in Leishmania parasites

RNA binding proteins (RBPs) are the primary gene regulators in kinetoplastids as transcriptional control is nearly absent, making Leishmania an exceptional model for investigating methylation of non-histone substrates. Arginine methylation is an evolutionarily conserved protein modification catalyzed by Protein aRginine Methyl Transferases (PRMTs). The chromatin modifier PRMT7 is the only Type III PRMT found in higher eukaryotes and a restricted number of unicellular eukaryotes. In Leishmania major, PRMT7 is a cytoplasmic protein implicit in pathogenesis with unknown substrates. Using comparative methyl-SILAC proteomics for the first time in protozoa, we identified 40 putative targets, including 17 RBPs hypomethylated upon PRMT7 knockout. PRMT7 can modify Alba3 and RBP16 trans-regulators (mammalian RPP25 and YBX2 homologs, respectively) as direct substrates in vitro. The absence of PRMT7 levels in vivo selectively reduces Alba3 mRNA-binding capacity to specific target transcripts and can impact the relative stability of RBP16 in the cytoplasm. RNA immunoprecipitation analyses demonstrate PRMT7-dependent methylation promotes Alba3 association with select target transcripts and thus indirectly stabilizes mRNA of a known virulence factor, δ-amastin surface antigen. These results highlight a novel role for PRMT7-mediated arginine methylation of RBP substrates, suggesting a regulatory pathway controlling gene expression and virulence in Leishmania. This work introduces Leishmania PRMTs as epigenetic regulators of mRNA metabolism with mechanistic insight into the functional manipulation of RBPs by methylation

Identification of membrane engineering targets for increased butanol tolerance in Clostridium saccharoperbutylacetonicum

There is a growing interest in the use of microbial cell factories to produce butanol, an industrial solvent and platform chemical. Biobutanol can also be used as a biofuel and represents a cleaner and more sustainable alternative to the use of conventional fossil fuels. Solventogenic Clostridia are the most popular microorganisms used due to the native expression of butanol synthesis pathways. A major drawback to the wide scale implementation and development of these technologies is the toxicity of butanol. Various membrane properties and related functions are perturbed by the interaction of butanol with the cell membrane, causing lower yields and higher purification costs. This is ultimately why the technology remains underemployed. This study aimed to develop a deeper understanding of butanol toxicity at the membrane to determine future targets for membrane engineering. Changes to the lipidome in Clostridium saccharoperbutylacetonicum N1–4 (HMT) throughout butanol fermentation were investigated with thin layer chromatography and mass spectrometry. By the end of fermentation, levels of phosphatidylglycerol lipids had increased significantly, suggesting an important role of these lipid species in tolerance to butanol. Using membrane models and in vitro assays to investigate characteristics such as permeability, fluidity, and swelling, it was found that altering the composition of membrane models can convey tolerance to butanol, and that modulating membrane fluidity appears to be a key factor. Data presented here will ultimately help to inform rational strain engineering efforts to produce more robust strains capable of producing higher butanol titres

A Partial Response to Reintroduced Chemotherapy in a Resistant Small Cell Lung Cancer Patient after Priming with RRx-001

As an exceedingly recalcitrant and highly aggressive tumor type without Food and Drug Administration-approved treatment or a known cure, the prognosis of recurrent extensive stage platinum-resistant/refractory small cell lung cancer (SCLC) is worse than other types of lung cancer, and many other tumor types, given a response rate of less than 10% and an overall survival of less than six months. It was broadly classified into three groups based on the initial response to cisplatin/etoposide therapy, platinum-refractory, platinum-resistant, and platinum-sensitive, extensive stage SCLC inevitably relapses, at which point the only standard options are to rechallenge with the first-line chemotherapeutic regimen in the case of sensitive disease or to start the topoisomerase I inhibitor, topotecan. Sensitive disease is defined by a response to the first-line therapy and a treatment-free interval of at least 90 days, while the definitions of refractory and resistant disease, respectively, are nonresponse to the first-line treatment or relapse within 90 days. As an important predictor of response to the second-line treatment, the clinical cutoff of three months (or two months in some cases) for resistant and sensitive disease, which along with performance status prognostically separates patients into high- and low-risk categories, dictates subsequent management. This case report presents a resistant SCLC patient enrolled on a Phase II clinical trial called QUADRUPLE THREAT (formerly TRIPLE THREAT, NCT02489903) who responded to reintroduced platinum doublets after sequential priming with the resistance-reversing epi-immunotherapeutic agent, RRx-001. In the QUADRUPLE THREAT clinical trial, both during priming with RRx-001 and during sequential treatment with platinum doublets, the patient maintained a good quality of life and performance status.Peer reviewe

The genomic and enzymatic basis for iridoid biosynthesis in cat thyme (Teucrium marum)

Iridoids are non-canonical monoterpenoids produced by both insects and plants. An example is the cat-attracting and insect-repelling volatile iridoid nepetalactone, produced by Nepeta sp. (catmint) and aphids. Recently, both nepetalactone biosynthetic pathways were elucidated, showing a remarkable convergent evolution. The iridoid, dolichodial, produced by Teucrium marum (cat thyme) and multiple insect species, has highly similar properties to nepetalactone but its biosynthetic origin remains unknown. We set out to determine the genomic, enzymatic, and evolutionary basis of iridoid biosynthesis in T. marum. First, we generated a de novo chromosome-scale genome assembly for T. marum using Oxford Nanopore Technologies long reads and proximity-by-ligation Hi-C reads. The 610.3 Mb assembly spans 15 pseudomolecules with a 32.9 Mb N50 scaffold size. This enabled identification of iridoid biosynthetic genes, whose roles were verified via activity assays. Phylogenomic analysis revealed that the evolutionary history of T. marum iridoid synthase, the iridoid scaffold-forming enzyme, is not orthologous to typical iridoid synthases but is derived from its conserved paralog. We discovered an enzymatic route from nepetalactol to diverse iridoids through the coupled activity of an iridoid oxidase cytochrome P450 and acetyltransferases, via an inferred acylated intermediate. This work provides a genomic resource for specialized metabolite research in mints and demonstration of the role of acetylation in T. marum iridoid diversity. This work will enable future biocatalytic or biosynthetic production of potent insect repellents, as well as comparative studies into iridoid biosynthesis in insects

Multi-Element Abundance Measurements from Medium-Resolution Spectra. IV. Alpha Element Distributions in Milky Way Dwarf Satellite Galaxies

We derive the star formation histories of eight dwarf spheroidal (dSph) Milky Way satellite galaxies from their alpha element abundance patterns. Nearly 3000 stars from our previously published catalog (Paper II) comprise our data set. The average [alpha/Fe] ratios for all dSphs follow roughly the same path with increasing [Fe/H]. We do not observe the predicted knees in the [alpha/Fe] vs. [Fe/H] diagram, corresponding to the metallicity at which Type Ia supernovae begin to explode. Instead, we find that Type Ia supernova ejecta contribute to the abundances of all but the most metal-poor ([Fe/H] < -2.5) stars. We have also developed a chemical evolution model that tracks the star formation rate, Types II and Ia supernova explosions, and supernova feedback. Without metal enhancement in the supernova blowout, massive amounts of gas loss define the history of all dSphs except Fornax, the most luminous in our sample. All six of the best-fit model parameters correlate with dSph luminosity but not with velocity dispersion, half-light radius, or Galactocentric distance.Comment: 28 pages, 14 figures; accepted for publication in ApJ; very minor editorial corrections in v