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BACKGROUND Migratory disc herniations can mimic neoplasms clinically and on imaging. Far lateral lumbar disc herniations usually compress the exiting nerve root and can be challenging to distinguish from a nerve sheath tumor due to the proximity of the nerve and characteristics on magnetic resonance imaging (MRI). These lesions can occasionally present in the upper lumbar spine region at the L1–2 and L2–3 levels. OBSERVATIONS The authors describe 2 extraforaminal lesions in the far lateral space at the L1–2 and L2–3 levels, respectively. On MRI, both lesions tracked along the corresponding exiting nerve roots with avid postcontrast rim enhancement and edema in the adjacent muscle tissue. Thus, they were initially concerning for peripheral nerve sheath tumors. One patient underwent fluorodeoxyglucose positron emission tomography–computed tomography (FDG PET-CT) screening and demonstrated moderate FDG uptake on PET-CT scan. In both cases, intraoperative and postoperative pathology revealed fibrocartilage disc fragments. LESSONS Differential diagnosis for lumbar far lateral lesions that are peripherally enhancing on MRI should include migratory disc herniation, regardless of the level of the disc herniations. Accurate preoperative diagnosis can aid in decision making for management, surgical approach, and resection.

Thyroid hormones are vital in metabolism, growth and development(1). Thyroid hormone synthesis is controlled by thyrotropin (TSH), which acts at the thyrotropin receptor (TSHR)(2). In patients with Graves’ disease, autoantibodies that activate the TSHR pathologically increase thyroid hormone activity(3). How autoantibodies mimic thyrotropin function remains unclear. Here we determined cryo-electron microscopy structures of active and inactive TSHR. In inactive TSHR, the extracellular domain lies close to the membrane bilayer. Thyrotropin selects an upright orientation of the extracellular domain owing to steric clashes between a conserved hormone glycan and the membrane bilayer. An activating autoantibody from a patient with Graves’ disease selects a similar upright orientation of the extracellular domain. Reorientation of the extracellular domain transduces a conformational change in the seven-transmembrane-segment domain via a conserved hinge domain, a tethered peptide agonist and a phospholipid that binds within the seven-transmembrane-segment domain. Rotation of the TSHR extracellular domain relative to the membrane bilayer is sufficient for receptor activation, revealing a shared mechanism for other glycoprotein hormone receptors that may also extend to other G-protein-coupled receptors with large extracellular domains.

Next-generation sequencing of pediatric gliomas has revealed the importance of molecular genetic characterization in understanding the biology underlying these tumors and a breadth of potential therapeutic targets. Promising targeted therapies include mTOR inhibitors for subependymal giant cell astrocytomas in tuberous sclerosis, BRAF and MEK inhibitors mainly for low-grade gliomas, and MEK inhibitors for NF1-deficient BRAF:KIAA fusion tumors. Challenges in developing targeted molecular therapies include significant intratumoral and intertumoral heterogeneity, highly varied mechanisms of treatment resistance and immune escape, adequacy of tumor penetrance, and sensitivity of brain to treatment-related toxicities.

Thyroid hormones are vital to growth and metabolism. Thyroid hormone synthesis is controlled by thyrotropin (TSH), which acts at the thyrotropin receptor (TSHR). Autoantibodies that activate the TSHR pathologically increase thyroid hormones in Graves’ disease. How autoantibodies mimic TSH function remains unclear. We determined cryogenic-electron microscopy structures of active and inactive TSHR. In inactive TSHR, the extracellular domain lies close to the membrane bilayer. TSH selects an upright conformation of the extracellular domain due to steric clashes between a conserved hormone glycan and the membrane bilayer. An activating autoantibody selects a similar upright conformation of the extracellular domain. Conformational changes in the extracellular domain are transduced to the seven transmembrane domain via a conserved hinge domain, a tethered peptide agonist, and a phospholipid that binds within the seven transmembrane domain. Rotation of the TSHR ECD relative to the membrane bilayer is sufficient for receptor activation, revealing a shared mechanism for other glycoprotein hormone receptors that may also extend to G protein-coupled receptors with large extracellular domains.

Accurate prediction of antigen presentation by human leukocyte antigen (HLA) class II molecules would be valuable for vaccine development and cancer immunotherapies. Current computational methods trained on in vitro binding data are limited by insufficient training data and algorithmic constraints. Here we describe MARIA (major histocompatibility complex analysis with recurrent integrated architecture; https://maria.stanford.edu/ ), a multimodal recurrent neural network for predicting the likelihood of antigen presentation from a gene of interest in the context of specific HLA class II alleles. In addition to in vitro binding measurements, MARIA is trained on peptide HLA ligand sequences identified by mass spectrometry, expression levels of antigen genes and protease cleavage signatures. Because it leverages these diverse training data and our improved machine learning framework, MARIA (area under the curve = 0.89–0.92) outperformed existing methods in validation datasets. Across independent cancer neoantigen studies, peptides with high MARIA scores are more likely to elicit strong CD4+ T cell responses. MARIA allows identification of immunogenic epitopes in diverse cancers and autoimmune disease. A neural network trained on diverse datasets improves prediction of HLA class II epitope presentation.

Next-generation sequencing of pediatric gliomas has revealed the importance of molecular genetic characterization in understanding the biology underlying these tumors and a breadth of potential therapeutic targets. Promising targeted therapies include mTOR inhibitors for subependymal giant cell astrocytomas in tuberous sclerosis, BRAF and MEK inhibitors mainly for low-grade gliomas, and MEK inhibitors for NF1-deficient BRAF:KIAA fusion tumors. Challenges in developing targeted molecular therapies include significant intratumoral and intertumoral heterogeneity, highly varied mechanisms of treatment resistance and immune escape, adequacy of tumor penetrance, and sensitivity of brain to treatment-related toxicities.

OBJECTIVEStereoelectroencephalography (SEEG) has increased in popularity for localization of epileptogenic zones in drug-resistant epilepsy because safety, accuracy, and efficacy have been well established in both adult and pediatric populations. Development of robot-guidance technology has greatly enhanced the efficiency of this procedure, without sacrificing safety or precision. To date there have been very limited reports of the use of this new technology in children. The authors present their initial experience using the ROSA platform for robot-guided SEEG in a pediatric population.METHODSBetween February 2016 and October 2017, 20 consecutive patients underwent robot-guided SEEG with the ROSA robotic guidance platform as part of ongoing seizure localization and workup for medically refractory epilepsy of several different etiologies. Medical and surgical history, imaging and trajectory plans, as well as operative records were analyzed retrospectively for surgical accuracy, efficiency, safety, and epilepsy outcomes.RESULTSA total of 222 leads were placed in 20 patients, with an average of 11.1 leads per patient. The mean total case time (± SD) was 297.95 (± 52.96) minutes and the mean operating time per lead was 10.98 minutes/lead, with improvements in total (33.36 minutes/lead vs 21.76 minutes/lead) and operative (13.84 minutes/lead vs 7.06 minutes/lead) case times/lead over the course of the study. The mean radial error was 1.75 (± 0.94 mm). Clinically useful data were obtained from SEEG in 95% of cases, and epilepsy surgery was indicated and performed in 95% of patients. In patients who underwent definitive epilepsy surgery with at least a 3-month follow-up, 50% achieved an Engel class I result (seizure freedom). There were no postoperative complications associated with SEEG placement and monitoring.CONCLUSIONSIn this study, the authors demonstrate that rapid adoption of robot-guided SEEG is possible even at a SEEG-naïve institution, with minimal learning curve. Use of robot guidance for SEEG can lead to significantly decreased operating times while maintaining safety, the overall goals of identification of epileptogenic zones, and improved epilepsy outcomes.

Rationale: Colorectal cancer (CRC) is the third most commonly diagnosed cancer around the world. Over the past several years, immunotherapy has demonstrated considerable clinical benefit in CRC therapy, and the number of immunologic therapies for cancer treatment continues to climb each year. Interleukin-15 (IL15), a potent pro-inflammatory cytokine, has emerged as a candidate immunomodulator for the treatment of CRC. Methods: In this study, we developed a novel gene delivery system with a self-assembly method using DOTAP and MPEG-PLA (DMA) to carry pIL15, denoted as DMA-pIL15 which was used to treat tumor-bearing mice. Results: Supernatant from lymphocytes treated with supernatant derived from CT26 cells transfected with DMA-pIL15 inhibited the growth of CT26 cells and induced cell apoptosis in vitro. Treatment of tumor-bearing mice with DMA-pIL15 complex significantly inhibited tumor growth in both subcutaneous and peritoneal models in vivo by inhibiting angiogenesis, promoting apoptosis, and reducing proliferation through activation of the host immune system. Conclusion: The IL-15 plasmid and DMA complex showed promise for treating CRC clinically as an experimental new drug.

Extracellular signal-regulated kinases 1 and 2 (ERK1/2) phosphorylate a variety of substrates important for survival and proliferation, and their activity is frequently deregulated in tumors. ERK pathway inhibitors have shown clinical efficacy as anti-cancer drugs, but most patients eventually relapse due to reactivation of the pathway. One factor limiting the efficacy of current therapeutics is the difficulty in reaching clinically effective inhibition of the ERK pathway in the absence of on-target toxicities. Here, we describe an assay suitable for high throughput screening to discover substrate selective ERK1/2 inhibitors, which may have a larger therapeutic window than conventional inhibitors. Specifically, we aim to target a substrate-binding pocket within the ERK1/2 catalytic domain outside of the catalytic cleft. The assay uses an AlphaScreen format to detect phosphorylation of a high-efficiency substrate harboring an essential docking site motif. Pilot screening established that the assay is suitably robust for high-throughput screening. Importantly, the assay can be conducted at high ATP concentrations, which we show reduces the discovery of conventional ATP-competitive inhibitors. These studies provide the basis for high-throughput screens to discover new classes of non-conventional ERK1/2 inhibitors.

For the past few years, immunotherapy has recently shown considerable clinical benefit in CRC therapy, and the application of immunologic therapies in cancer treatments continues to increase perennially. Interleukin-12, an ideal candidate for tumor immunotherapy, could activate both innate and adaptive immunities. In this study, we developed a novel gene delivery system with a self-assembly method by MPEG-PLA and DOTAP(DMP) with zeta-potential value of 38.5mV and size of 37.5nm. The supernatant of lymphocytes treated with supernatant from Ct26 transfected pIL12 with DMP could inhibit Ct26 cells growth ex vivo. Treatment of tumor-bearing mice with DMP-pIL12 complex has significantly inhibited tumor growth at both the subcutaneous and peritoneal model in vivo by inhibiting angiogenesis, promoting apoptosis and reducing proliferation. The IL-12 plasmid and DMP complex may be used to treat the colorectal cancer in clinical as a new drug.

In previous studies, honokiol (Hon) has been demonstrated to have anti-tumorigenic effects. However, its poor water solubility and low bioavailability limit its potential as an orally-administered anti-cancer compound. This study presents work toward improving the water solubility and antitumor effects of honokiol through the use of self-assembling, biodegradable micelles of monomethoxy poly(ethylene glycol)–poly(e-caprolactone) copolymer (MPEG–PCL). These honokiol-containing polymeric micelles (Hon/MPEG–PCL) release the compound slowly over an extended period of time. In addition, treatment with Hon/MPEG–PCL inhibits the growth of osteosarcoma cells and induces apoptosis of these cells more effectively than free honokiol in vitro. Further, in a nude mouse model of osteosarcoma, Hon/MPEG–PCL inhibits the growth of tumors, induces apoptosis, and inhibits angiogenesis more effectively than the same dose of free honokiol. This shows that Hon/MPEG–PCL enhances the antitumor effects of honokiol in vivo, and, as a result, shows great promise as a clinical treatment for osteosarcoma.

The phosphatidylinositol phosphate kinase (PIPK) family of enzymes is primarily responsible for converting singly phosphorylated phosphatidylinositol derivatives to phosphatidylinositol bisphosphates. As such, these kinases are central to many signaling and membrane trafficking processes in the eukaryotic cell. The three types of phosphatidylinositol phosphate kinases are homologous in sequence but differ in catalytic activities and biological functions. Type I and type II kinases generate phosphatidylinositol 4,5-bisphosphate from phosphatidylinositol 4-phosphate and phosphatidylinositol 5-phosphate, respectively, whereas the type III kinase produces phosphatidylinositol 3,5-bisphosphate from phosphatidylinositol 3-phosphate. Based on crystallographic analysis of the zebrafish type I kinase PIP5Kα, we identified a structural motif unique to the kinase family that serves to recognize the monophosphate on the substrate. Our data indicate that the complex pattern of substrate recognition and phosphorylation results from the interplay between the monophosphate binding site and the specificity loop: the specificity loop functions to recognize different orientations of the inositol ring, whereas residues flanking the phosphate binding Arg244 determine whether phosphatidylinositol 3-phosphate is exclusively bound and phosphorylated at the 5-position. This work provides a thorough picture of how PIPKs achieve their exquisite substrate specificity.

Erratum Erratum to ‘‘Pharmacophore modeling strategies for the development of novel nonsteroidal inhibitors of human aromatase (CYP19)” [Bioorg. Med. Chem. Lett. 20 (2010) 3050] Yagmur Muftuoglu , Gabriela Mustata b,* Departments of Biophysics and Chemical Biomolecular Engineering, Johns Hopkins University, Baltmore, MD 21218, United States Department of Computational Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, United States

The novel antiretroviral 4′-ethynyl-2-fluoro-2′-deoxyadenosine (EFdA) is a potent nucleoside HIV-1 reverse transcriptase (RT) inhibitor (NRTI). Unlike other FDA-approved NRTIs, EFdA contains a 3′-hydroxyl. Pre-steady-state kinetics showed RT preferred incorporating EFdA-TP over native dATP. Moreover, RT slowly inserted nucleotides past an EFdA-terminated primer, resulting in delayed chain termination with unaffected fidelity. This is distinct from KP1212, another 3′-hydroxyl-containing RT inhibitor considered to promote viral lethal mutagenesis. New mechanistic features of RT inhibition by EFdA are revealed.

Over the last 40 years since “the war on cancer” began, cancer death rates have been significantly declining. Major advances in molecular and cellular biology have led to several breakthroughs in the field of cancer research. One of the most important advances in this area was probably the identification of genes that are closely involved in cancer initiation, progression, invasion, and angiogenesis, particularly those that cause cancer, those that suppress it, and those that promote or inhibit programmed cell death (apoptosis). As a result, the rates of new diagnoses and the rates of death from all cancers combined continue to decline. The National Cancer Institute’s Cancer Trends Report for 2009/2010 highlights the fact that the four most common cancers – of the prostate, breast, lung, and colorectal, specifically – have dropped considerably in the past few years (National Cancer Institute Cancer Trends Progress Report 2009/2010). Toward the study and treatment of such cancers, there are 680 genes, 545 proteins and 3 RNAs associated with 102 different types of cancer that have been identified to date (National Cancer Institute Cancer Trends Progress Report 2009/2010). Targeting these, a total of 1370 drugs, out of which 1056 are small molecules and 314 are biologics, are either in preclinical or clinical trials or are already FDA approved (National Cancer Institute Cancer

Background The present study compares antiepileptic drugs and aromatase (CYP19) inhibitors for chemical and structural similarity. Human aromatase is well known as an important pharmacological target in anti-breast cancer therapy, but recent research demonstrates its role in epileptic seizures, as well. The current antiepileptic treatment methods cause severe side effects that endanger patient health and often preclude continued use. As a result, less toxic and more tolerable antiepileptic drugs (AEDs) are needed, especially since every individual responds differently to given treatment options. Methods Through a pharmacophore search, this study shows that a model previously designed to search for new classes of aromatase inhibitors is able to identify antiepileptic drugs from the set of drugs approved by the Food and Drug Administration. Chemical and structural similarity analyses were performed using five potent AIs, and these studies returned a set of AEDs that the model identifies as hits. Results The pharmacophore model returned 73% (19 out of 26) of the drugs used specifically to treat epilepsy and approximately 82% (51 out of 62) of the compounds with anticonvulsant properties. Therefore, this study supports the possibility of identifying AEDs with a pharmacophore model that had originally been designed to identify new classes of aromatase inhibitors. Potential candidates for anticonvulsant therapy identified in this manner are also reported. Additionally, the chemical and structural similarity between antiepileptic compounds and aromatase inhibitors is proved using similarity analyses. Conclusions This study demonstrates that a pharmacophore search using a model based on aromatase inhibition and the enzyme's structural features can be used to screen for new candidates for antiepileptic therapy. In fact, potent aromatase inhibitors and current antiepileptic compounds display significant - over 70% - chemical and structural similarity, and the similarity analyses performed propose a number of antiepileptic compounds with high potential for aromatase inhibition.

The present study utilizes for the first time the structural information of aromatase, an important pharmacological target in anti-breast cancer therapy, to extract the pharmacophoric features important for interactions between the enzyme and its substrate, androstenedione. A ligand-based pharmacophore model developed from the most comprehensive list of nonsteroidal aromatase inhibitors (AIs) is described and explained, as well. This study demonstrates that the ligand-based pharmacophore model contributes to efficacy while the structure-based model contributes to specificity. It is also shown that a 'merged' model (i.e., a merged structure-based and ligand-based model) can successfully identify known AIs and differentiate between active and inactive inhibitors. Therefore, this model can be effectively used to identify the next generation of highly specific and less toxic aromatase inhibitors for breast cancer treatment.