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Oxygen, which is necessary for sustaining energy metabolism, is consumed in many biochemical reactions in eukaryotes. When the oxygen supply is insufficient for maintaining multiple homeostatic states at the cellular level, cells are subjected to hypoxic stress. Hypoxia induces adaptive cellular responses mainly through hypoxia-inducible factors (HIFs), which are stabilized and modulate the transcription of various hypoxia-related genes. In addition, many epigenetic regulators, such as DNA methylation, histone modification, histone variants, and adenosine triphosphate-dependent chromatin remodeling factors, play key roles in gene expression. In particular, hypoxic stress influences the activity and gene expression of histone-modifying enzymes, which controls the posttranslational modification of HIFs and histones. This review covers how histone methylation and histone acetylation enzymes modify histone and nonhistone proteins under hypoxic conditions and surveys the impact of epigenetic modifications on gene expression. In addition, future directions in this area are discussed.

Hemophilia is a hereditary disease that remains incurable. Although innovative treatments such as gene therapy or bispecific antibody therapy have been introduced, substantial unmet needs still exist with respect to achieving long-lasting therapeutic effects and treatment options for inhibitor patients. Antithrombin (AT), an endogenous negative regulator of thrombin generation, is a potent genome editing target for sustainable treatment of patients with hemophilia A and B. In this study, we developed and optimized lipid nanoparticles (LNPs) to deliver Cas9 mRNA along with single guide RNA that targeted AT in the mouse liver. The LNP-mediated CRISPR-Cas9 delivery resulted in the inhibition of AT that led to improvement in thrombin generation. Bleeding-associated phenotypes were recovered in both hemophilia A and B mice. No active off-targets, liver-induced toxicity, and substantial anti-Cas9 immune responses were detected, indicating that the LNP-mediated CRISPR-Cas9 delivery was a safe and efficient approach for hemophilia therapy., Description, We showed that lipid nanoparticle–packed CRISPR- mediated antithrombin gene editing offers a sustainable and safe hemophilia therapy.

Preclinical studies using genetically engineered mouse models (GEMM) have the potential to expedite the development of effective new therapies; however, they are not routinely integrated into drug development pipelines. GEMMs may be particularly valuable for investigating treatments for less common cancers, which frequently lack alternative faithful models. Here, we describe a multicenter cooperative group that has successfully leveraged the expertise and resources from philanthropic foundations, academia, and industry to advance therapeutic discovery and translation using GEMMs as a preclinical platform. This effort, known as the Neurofibromatosis Preclinical Consortium (NFPC), was established to accelerate new treatments for tumors associated with neurofibromatosis type 1 (NF1). At its inception, there were no effective treatments for NF1 and few promising approaches on the horizon. Since 2008, participating laboratories have conducted 95 preclinical trials of 38 drugs or combinations through collaborations with 18 pharmaceutical companies. Importantly, these studies have identified 13 therapeutic targets, which have inspired 16 clinical trials. This review outlines the opportunities and challenges of building this type of consortium and highlights how it can accelerate clinical translation. We believe that this strategy of foundation–academic–industry partnering is generally applicable to many diseases and has the potential to markedly improve the success of therapeutic development. Cancer Res; 77(21); 5706–11. ©2017 AACR.

Bone tissue is continuously remodeled by the coordinated action of osteoclasts and osteoblasts. Nuclear factor-activated T cells c1 (NFATc1) is a well-known transcription factor for osteoclastogenesis and transcriptionally activated by the c-Fos and nuclear factor-kappa B (NF-&kappa, B) signaling pathways in response to receptor activation of NF-&kappa, B ligand (RANKL). Since excessive RANKL signaling causes an increase of osteoclast formation and bone resorption, inhibition of RANKL or its signaling pathway is an attractive therapeutic approach to the treatment of pathologic bone loss. In this study, we show that an ethyl acetate fraction (LEA) from the shiitake mushroom, Lentinula edodes, inhibited RANKL-induced osteoclast differentiation by blocking the NFATc1 signaling pathway. We found that the water extract and its subsequent ethyl acetate fraction of L. edodes significantly suppressed osteoclast formation. Comparative transcriptome analysis revealed that LEA specifically downregulated a set of RANKL target genes, including Nfatc1. Next, we found that LEA suppresses Nfatc1 expression mainly through the inhibition of the transactivity of p65 and NFATc1. Moreover, treatment of LEA rescued an osteoporotic phenotype in a zebrafish model of glucocorticoid-induced osteoporosis. Collectively, our findings define an undocumented role of the shiitake mushroom extract in regulating bone development.

The bone tissue is a dynamic complex that constitutes of several interdependent systems and is continuously remodeled through the concerted actions of bone cells. Osteoblasts are mononucleated cells, derived from mesenchymal stem cells, responsible for bone formation. Osteoclasts are large multinucleated cells that differentiate from hematopoietic progenitors of the myeloid lineage and are responsible for bone resorption. The lineage-specific differentiation of bone cells requires an epigenetic regulation of gene expressions involving chromatin dynamics. The key step for understanding gene regulatory networks during bone cell development lies in characterizing the chromatin modifying enzymes responsible for reorganizing and potentiating particular chromatin structure. This review covers the histone-modifying enzymes involved in bone development, discusses the impact of enzymes on gene expression, and provides future directions and clinical significance in this area.

In Korea, typhoid fever is a rare disease due to improved living standards. However, typhoid fever remains a major burden in developing countries and regions, such as India and Southeast Asia. In this study, we isolated Salmonella Typhi (S. Typhi) from eight patients with typhoid fever who were travelers returning from India. The strains isolated were characterized by antimicrobial susceptibility profiling and whole-genome sequencing (WGS) analysis. All strains were resistant to nalidixic acid and azithromycin. Among them, four isolates were highly resistant to ciprofloxacin (MIC ≥32 μg/ml); these strains have not been confirmed in Korea PulseNet DB. According to WGS, the ciprofloxacin-resistant strains belong to the global dominant multidrug-resistant (MDR) haplotype H58 (SNP glpA C1047T, SptP protein Q185* (premature stop codon)) and do not harbor the MDR plasmid. H58-associated SNPs in membrane and metabolism genes, including yhdA, yajI, hyaE, tryE, rlpB and metH, are present. Additionally, phylogenetic analysis assigned the H58 strains to sublineage II, whereas the non-H58 strains are closely related to haplotype H50. The presence of high-level ciprofloxacin-resistant S. Typhi haplotype H58 in Korea was first confirmed as due to influx from overseas via travelers. This study provides information about intercontinental drug-resistant transmission between countries and suggests that travelers need to be careful about personal hygiene., Author summary Typhoid fever is a systemic human disease that involves gastroenteritis, fever, and severe diarrhea caused by Salmonella enterica serotype Typhi (S. Typhi) and requires prompt antibiotic treatment. Due to improved living standards, it has become a rare disease but is still prevalent in developing countries such as India and Southeast Asia. Most reported cases are related to travelers or immigrants from these regions. Because of treatment failure, serious morbidity, and economic loss, there is a global health issue with the emergence of antimicrobial-resistant strains associated with fluoroquinolones and third-generation cephalosporins. Of antimicrobial-resistant S. Typhi, haplotype H58 is a dominant multidrug-resistant lineage that has been reported in endemic regions over the past two decades. We identified fluoroquinolone resistance in cases of S. Typhi infection after travel to India. Among them, some strains highly resistant to ciprofloxacin were confirmed to have characteristics of haplotype H58. In Korea, S. Typhi haplotype H58 from travelers has not been confirmed before. This study provides information about intercontinental drug-resistant transmission between countries and suggests that travelers need to be careful about personal hygiene.

Global health competency is an essential capacity for nursing students. This study evaluated the effect of a global outreach program on global health competency and cultural self-efficacy in nursing students and examined the students' experiences with the program. Participants included thirty-one undergraduate nursing students at a university in Seoul, Republic of Korea, who participated in a global outreach program in 2015 and 2016. Quantitative data were collected before and after program participation using questionnaires evaluating global health competency and cultural self-efficacy, and were analyzed using descriptive statistics and paired t-tests. Both global health competency and cultural self-efficacy increased significantly after the global outreach program. Qualitative data were collected via focus group interviews and reflective journals, and were analyzed using conventional content analysis and thematic analysis, respectively. The results of the content and thematic analyses were compared, and two themes and eight-sub-themes were finally extracted through the data analysis. The program was effective in improving nursing students' global health competency and cultural self-efficacy.

Background In November 2015, reuse of needles and syringes in conjunction with an increase in cases of HCV at a clinic in Korea was reported and investigated by public health authorities. Patients who received injections at the clinic from the first time this infection control breach may have occurred in 2008 through 2015 when the practice was stopped were offered screening for HCV and other blood-borne pathogens such as HIV, HTLV, HBV, syphilis, and malaria. Objectives The aim of this study was to assess whether an outbreak of hepatitis C had occurred among the potentially exposed clinic patients due to this infection control breach. Study Design We performed hepatitis C viral RNA load tests and genotyping using plasma from hepatitis C antibody-positive individuals who had visited the clinic between May 2008 and November 2015. We analyzed the core-E2 and NS5B regions of the virus from RNA-positive samples by constructing a phylogenetic tree based on maximum likelihood analysis. To identify transmission risk factors and epidemiological relationships among the patients, we reviewed their medical records, assessed staff infection control practices and performed environmental inspection of the clinic. Environmental samples from medication room surfaces and medication vial contents were tested for HCV RNA. Results and Conclusions Among the 1721 patients tested, 96 were IgG-positive and 70 were viral RNA-positive. Among the 61 patients whose viral loads were greater than the detection limit, 41 (67.2%) were classified as genotype 1a, 1 (1.6%) as genotype 1b, 18 (29.5%) as genotype 1, and one (1.6%) as genotype 2. After sequencing, 12 genotype 1 cases were further classified as genotype 1a (11) or 1b (1). The sequences of the core-E2 and NS5B regions of 45 patients formed a monophyletic cluster distinct from genotype 1a. The hepatitis C virus sequences from patients and environmental specimens were well-matched in the partial E1 gene region. We detected genotype 1a RNA in environmental specimens, indicating a healthcare-associated outbreak caused by reuse of syringes and contaminated multi-dose vials. Our molecular epidemiological investigation of hepatitis C genotype 1a, rare in Korea, will aid investigations of infection sources during future pathogen outbreaks.

Osteoporosis is a common disorder of bone remodeling, caused by the imbalance between bone resorption by osteoclasts and bone formation by osteoblasts. Recently, we reported that matrix metalloproteinase-9 (MMP-9)-dependent histone H3 proteolysis is a key event for proficient osteoclast formation. Although it has been reported that several MMP-9 inhibitors, such as tetracycline and its derivatives, show an inhibitory effect on osteoclastogenesis, the molecular mechanisms for this are not fully understood. Here we show that tetracycline analogs, especially tigecycline and minocycline, inhibit osteoclast formation by blocking MMP-9-mediated histone H3 tail cleavage. Our molecular docking approach found that tigecycline and minocycline are the most potent inhibitors of MMP-9. We also observed that both inhibitors significantly inhibited H3 tail cleavage by MMP-9 in vitro. These compounds inhibited receptor activator of nuclear factor kappaB ligand (RANKL)-induced osteoclast formation by blocking the NFATc1 signaling pathway. Furthermore, MMP-9-mediated H3 tail cleavage during osteoclast differentiation was selectively blocked by these compounds. Treatment with both tigecycline and minocycline rescued the osteoporotic phenotype induced by prednisolone in a zebrafish osteoporosis model. Our findings demonstrate that the tetracycline analogs suppress osteoclastogenesis via MMP-9-mediated H3 tail cleavage, and suggest that MMP-9 inhibition could offer a new strategy for the treatment of glucocorticoid-induced osteoporosis.

The neurofibromatoses (NF) are a group of rare genetic disorders that can affect all races equally at an incidence from 1:3000 (NF1) to a log unit lower for NF2 and schwannomatosis. Since the research community is reporting an increasing number of malignant cancers that carry mutations in the NF genes, the general interest of both the research and pharma community is increasing and the authors saw an opportunity to present a novel, fresh approach to drug discovery in NF. The aim of the paper is to challenge the current drug discovery approach to NF, whereby existing targeted therapies that are either in the clinic or on the market for other disease indications are repurposed for NF. We offer a suggestion for an alternative drug discovery approach. In the new approach, selective and tolerable targeted therapies would be developed for NF and later expanded to patients with more complex diseases such as malignant cancer in which the NF downstream pathways are deregulated. The Children's Tumor Foundation, together with some other major NF funders, is playing a key role in funding critical initiatives that will accelerate the development of better targeted therapies for NF patients, while these novel, innovative treatments could potentially be beneficial to molecularly characterized cancer patients in which NF mutations have been identified.

Mammary carcinoma frequently metastasizes to specific organs, including the regional lymph nodes, the lung and bone marrow. The mechanisms that guide organ-specific metastasis and the molecular players that are involved remain to be established. To gain insight into this problem, we used an orthotopic model of breast cancer in which the MDA-MB-435 cells are implanted into the mouse mammary fat pad. Sublines that preferentially metastasized to specific sites were isolated by excising metastatic tumors and growing explants of these tumors in culture. Cells lines that preferentially metastasize to the lymph node and thoracic cavity were obtained. The gene expression profiles of primary tumors from these sublines were then compared with cDNA arrays containing 5,800 known genes. In tumors that preferentially metastasize to the lymph node, several genes encoding adhesion and matrix proteins were upregulated. Genes encoding proteins involved in metabolism were downregulated. One of the upregulated genes in lymph-homing tumors was CD73. Immunohistochemistry showed that the CD73 protein is also upregulated in primary tumors of this cell line and that its expression is elevated in the lymph node metastases. CD73 is a transmembrane protein that has previously been implicated in the homing of normal lymphocytes to the nodes. This raises the hypothesis that tumors preferentially metastasize to lymph nodes by using CD73 to mimic part of the lymphocyte homing process.

Background: The administration of oral pregabalin preoperatively has been reported to reduce acute postoperative pain. However, no clinical study to date has yet fully investigated whether or not pregabalin premedication affects sensory and motor blocks using spinal anesthesia and its effect upon early postoperative pain management. This prospective, randomized, and double-blind clinical study was designed to evaluate the efficacy of a single dose of pregabalin in terms of spinal blockade duration and its potential opioid-sparing effect during the first 24 hours subsequent to urogenital surgery. Methods: Forty-four patients scheduled for urogenital surgery under spinal anesthesia were randomly allocated to 2 groups: group C (no premedication; orally administered placebo 2 hours before surgery) and group P (orally administered 150 mg pregabalin 2 hours before surgery). Results: The duration of sensory and motor blockade was significantly prolonged in group P patients when compared with that in group C patients, and the pain scores at postoperative 6 and 24 hours were significantly lower in group P patients. Requests for analgesics during the first postoperative 24 hours were lower among group P patients. Conclusion: Premedication with a single dose of 150 mg pregabalin before surgery promoted the efficacy of intrathecal bupivacaine and improved postoperative analgesia in patients undergoing urogenital surgery under spinal anesthesia.

Acrylamide has been known to have a neurotoxic effect which is associated with nerve damage in both the central and peripheral nervous systems. Since neural cell adhesion molecule (NCAM) plays an important role in the processes of neuronal development and synaptic plasticity, the down-regulation of NCAM may lead impaired spatial memory and reduced long-term potentiation. We examined the effect of acrylamide on NCAM expression and the mechanisms of its effect in human neuroblastoma cells. Treatment with acrylamide resulted in the decrease of NCAM expression, which was reversed by CK2 inhibitor, 4,5,6,7-tetrabromobenzotriazole (TBB). Moreover, Western blot analysis showed that acrylamide induced the expression of CK2. Acrylamide dose-dependently decreased the DNA binding affinity of the Ikaros transcription factor, which is a bifunctional differentiation factor. In addition, the cells treated with acrylamide and CK2 inhibitor showed increased Ikaros activity compared with the acrylamide treatment only. Small interfering RNA-mediated depletion of CK2-α also increased Ikaros activity in acrylamide-treated cells. Overall, these data suggest that acrylamide decreases the Ikaros DNA binding activity via the CK2 pathway, resulting in a decrease of NCAM expression and provide further insight into the mechanisms underlying acrylamide actions.

Purpose This phase II study evaluated the efficacy and safety of ixabepilone as neoadjuvant therapy for invasive breast cancer not amenable to breast conservation surgery. Gene expression studies were undertaken using genes that were identified as potentially associated with sensitivity/resistance to ixabepilone in prior preclinical investigations. Patients and Methods Patients with invasive breast cancer ≥ 3 cm were eligible. Ixabepilone 40 mg/m2 was administered as a 3-hour intravenous infusion on day 1 of a 21-day cycle for four or fewer cycles. Results One hundred sixty-one patients were treated. The overall complete pathologic response (pCR) rate was 18% in breast and 29% in estrogen receptor (ER) –negative patients. Gene expression data were available for 134 patients. ER gene expression (ER1) was inversely related to pCR in breast and had a positive predictive value (PPV) of 37% and negative predictive value (NPV) of 92%. A 10-gene penalized logistic regression (PLR) model developed from 200 genes predictive of ixabepilone sensitivity in preclinical experiments included ER and tau and had higher PPV (45%) and comparable NPV (89%) to ER1. Grade 3 to 4 adverse events (AEs) were reported for 32% of patients. Except for neutropenia and leukopenia, all grade 3 to 4 AEs occurred in ≤ 3% of patients. Reversible peripheral neuropathy was experienced by 3% of patients. Conclusion ER, microtubule-associated protein tau, and a 10-gene PLR model that included ER were identified as predictors of ixabepilone-induced pCR. Results indicate an inverse relation between ER expression levels and ixabepilone sensitivity. Neoadjuvant ixabepilone demonstrated promising activity and a manageable safety profile in patients with invasive breast tumors.