Therapeutic efficacy of RAS inhibitor trametinib using a juvenile myelomonocytic leukemia patient-derived xenograft model.

Juvenile myelomonocytic leukemia (JMML) is an aggressive pediatric leukemia with few effective treatments and poor outcomes even after stem cell transplantation, the only current curative treatment. We developed a JMML patient-derived xenograft (PDX) mouse model and demonstrated the in vivo therapeutic efficacy and confirmed the target of trametinib, a RAS-RAF-MEK-ERK pathway inhibitor, in this model. A PDX model was created through transplantation of patient JMML cells into mice, up to the second generation, and successful engraftment was confirmed using flow cytometry. JMML PDX mice were treated with trametinib versus vehicle control, with a median survival of 194 days in the treatment group versus 124 days in the control group (p = 0.02). Trametinib's target as a RAS pathway inhibitor was verified by showing inhibition of ERK phosphorylation using immunoblot assays. In conclusion, trametinib monotherapy significantly prolongs survival in our JMML PDX model by inhibiting the RAS pathway. Our model can be effectively used for assessment of novel targeted treatments, including potential combination therapies, to improve JMML outcomes.

Efficacy of a 4-Antigen Staphylococcus aureus Vaccine in Spinal Surgery: The STaphylococcus aureus suRgical Inpatient Vaccine Efficacy (STRIVE) Randomized Clinical Trial.

BACKGROUND: Staphylococcus aureus is a global pathogen that is frequently responsible for healthcare-associated infections, including surgical site infections (SSIs). Current infection prevention and control approaches may be limited, with S. aureus antibiotic resistance remaining problematic. Thus, a vaccine to prevent or reduce S. aureus infection is critically needed. We evaluated the efficacy and safety of an investigational 4-antigen S. aureus vaccine (SA4Ag) in adults undergoing elective open posterior spinal fusion procedures with multilevel instrumentation. METHODS: In this multicenter, site-level, randomized, double-blind trial, patients aged 18-85 years received a single dose of SA4Ag or placebo 10-60 days before surgery. SA4Ag efficacy in preventing postoperative S. aureus bloodstream infection and/or deep incisional or organ/space SSIs was the primary end point. Safety evaluations included local reactions, systemic events, and adverse events (AEs). Immunogenicity and colonization were assessed. RESULTS: Study enrollment was halted when a prespecified interim efficacy analysis met predefined futility criteria. SA4Ag showed no efficacy (0.0%) in preventing postoperative S. aureus infection (14 cases in each group through postoperative day 90), despite inducing robust functional immune responses to each antigen compared with placebo. Colonization rates across groups were similar through postoperative day 180. Local reactions and systemic events were mostly mild or moderate in severity, with AEs reported at similar frequencies across groups. CONCLUSIONS: In patients undergoing elective spinal fusion surgical procedures, SA4Ag was safe and well tolerated but, despite eliciting substantial antibody responses that blocked key S. aureus virulence mechanisms, was not efficacious in preventing S. aureus infection. Clinical Trials Registration. NCT02388165.

Controlled Assembly of Fluorophores inside a Nanoliposome.

Cellular compartmentalization plays an essential role in organizing the complex and multiple biochemical reactions in the cell. An artificial compartment would provide powerful strategies to develop new biochemical tools for material production and diagnosis, but it is still a great challenge to synthesize the compartments that encapsulate materials of interest while controlling their accurate locations, numbers, and stoichiometry. In this study, we evaluated chemical characteristics of a liposome-encapsulated compartment, which has great potential to locate various materials of interest with precise control of their locations and numbers in the compartment. A nanoliposome was constructed inside a ring-shaped DNA origami skeleton according to the method of Yang et al., and further equipped with a double-stranded DNA platform to assemble molecules of interest in the nanoliposome. Upon formation of the nanoliposome, a pH-sensitive fluorophore on the bridged platform showed little or no response to the pH change of the outer buffer, ensuring that the molecules assembled on the platform are effectively shielded from the outer environment. The ring-shaped DNA skeleton equipped with a double-stranded DNA platform allows spatial assembly of several functional molecules inside the nanoliposome to isolate them from the outer environment.

Treatment of hepatocellular carcinoma with autologous platelets encapsulating sorafenib or lenvatinib: A novel therapy exploiting tumor-platelet interactions.

Hepatocellular carcinoma (HCC) activates platelets through the action of adjacent sinusoidal cells. Activated platelets bind to tumor-associated endothelial cells and release growth factors that promote tumor progression. We hypothesized that platelets encapsulated with tumor inhibitors would function as drug carriers for tumor therapy. We propose a therapeutic strategy for HCC using autologous platelets encapsulating multiple tyrosine kinase inhibitors in a rat chemically induced HCC model. Sorafenib or lenvatinib was encapsulated in platelets isolated from tumor-bearing rats in vitro. The rats were divided into groups that received repeated intravenous injections (twice a week for 10 weeks) of the following materials: placebo, sorafenib (SOR), lenvatinib (LEN), autologous platelets, autologous platelets encapsulating sorafenib (SOR-PLT) and autologous platelets encapsulating lenvatinib (LEN-PLT). The therapeutic effect was then analyzed by ultrasonography (US) and histopathological analysis. Histopathological and US analysis demonstrated extensive tumor necrosis in the tumor tissue of SOR-PLT or LEN-PLT, but not in other experimental groups. By liquid chromatography-mass spectrometry, more abundant sorafenib was detected in tumor tissues after SOR-PLT administration than in surrounding normal tissues, but no such difference in sorafenib level was observed with SOR administration. Therefore, the use of autologous platelets encapsulating drugs might be a novel therapeutic strategy for HCC.

Soluble thrombomodulin ameliorates aberrant hemostasis after rewarming in a rat accidental hypothermia model.

BACKGROUND: Accidental hypothermia (AH) sometimes leads to coagulation disorder, especially in severe AH. We previously demonstrated that intrasplenic platelet activation caused aberrant hemostasis and thrombus formation after rewarming in a murine AH model. However, no study has focused on the appropriate management of platelets causing coagulation activation after rewarming of AH. We investigated whether or not recombinant soluble thrombomodulin (rTM) can suppress thrombosis formation after rewarming using a rat AH model. METHODS: Wistar rats were exposed to an ambient temperature of -20 °C under general anesthesia until their rectal temperature decreased to 26 °C. The Hypo group rats (n = 5) were immediately euthanized, while the Hypo/Re group (n = 5) and rTM group rats (n = 5), which were administered rTM (1 mg/kg) via the tail vein, were rewarmed until the rectal temperature returned to 34 °C and then euthanized 6 h later. Tissue and blood samples were collected from all rats for histopathological and coagulation analyses at euthanasia. RESULTS: There was no significant change in the D-dimer level in the Hypo group rats, while the D-dimer level was significantly elevated at 6 h after rewarming in the Hypo/Re group rats (P = 0.015), and histopathology detected both fibrin and platelets in the renal glomerulus. However, the rTM group rats did not show any elevation of the D-dimer levels at 6 h after rewarming, and no fibrin was noted on histopathology. CONCLUSIONS: rTM may be useful as an appropriate anticoagulant in cases of aberrant hemostasis after rewarming of AH.

GAREM1 is involved in controlling body mass in mice and humans.

The adaptor protein GAREM has two subtypes. Each is involved in Erk activation signaling downstream of the cell growth factor receptor in cultured cells. Regarding their role in individual animals, we have previously reported that mice deficient in GAREM2, which is highly expressed in the brain, exhibit emotional changes. In this paper, we report an amino acid substitution mutation (K291R) in GAREM1, in a patient with idiopathic short stature, which indicates that the mutant exhibits dominant-negative properties. The GAREM K291R mutant did not promote Erk activation in EGF-stimulated cultured cells. Similar features were also observed in cells in which GAREM1 expression was suppressed by genome editing; along with Erk, phosphorylation of S6 kinase and 4EBP1, whose activation is necessary for cell proliferation and biological growth, were inhibited Furthermore, we generated mice deficient in GAREM1 and showed that the mutant mice are lighter in weight. Overall, the results of this paper suggest that GAREM1 is required for normal growth and for maintaing average body size in humans and mice.

Probiotic-derived heptelidic acid exerts antitumor effects on extraintestinal melanoma through glyceraldehyde-3-phosphate dehydrogenase activity control.

BACKGROUND: Several microorganisms inhabit the mammalian gastrointestinal tract and are associated with the pathogenesis of various diseases, including cancer. Recent studies have indicated that several probiotics produce antitumor molecules and inhibit host tumor progression. We demonstrated that heptelidic acid (HA), a sesquiterpene lactone derived from the probiotic Aspergillus oryzae, exerts antitumor effects against pancreatic cancer in vitro and in vivo. In this study, the antitumor effects of HA against extraintestinal melanoma were assessed in vitro and in vivo. RESULTS: Sulforhodamine B (SRB) assay revealed that the growth of B16F10 cells was significantly inhibited by HA in a concentration-dependent manner. The enzymatic activity of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) decreased in proportion with the growth inhibition effect of HA. Moreover, oral HA administration significantly suppressed the growth of transplanted B16F10 tumors without any significant changes in biochemical test values. Moreover, GAPDH activity in the transplanted tumor tissues in the HA group significantly decreased compared with that in the PBS group. CONCLUSION: This study suggests that orally administered HA was absorbed in the gastrointestinal tract, reached the cancer cells transplanted in the skin, and inhibited GAPDH activity, thereby inhibiting the growth of extraintestinal melanoma cells. Thus, this study proposes a novel system for extraintestinal tumor regulation via gut bacteria-derived bioactive mediators.

Bacteria-derived ferrichrome inhibits tumor progression in sporadic colorectal neoplasms and colitis-associated cancer.

BACKGROUND: Colorectal cancers develop through several pathways, including the adenoma-carcinoma sequence and colitis-associated carcinogenesis. An altered intestinal microflora has been reported to be associated with the development and progression of colorectal cancer via these pathways. We identified Lactobacillus casei-derived ferrichrome as a mediator of the bacterial anti-tumor effect of colorectal cancer cells through the upregulation of DDIT3. In this study, we investigated the anti-tumor effects of ferrichrome on precancerous conditions and cancer cells associated with sporadic as well as colitis-associated colorectal cancer. METHODS: SRB and MTT assays were performed to assess growth inhibition in vitro. Eighteen organoids were prepared from biopsy specimens obtained by colonoscopy. An AOM-DSS carcinogenesis model and xenograft model of colorectal cancer cells were generated for the assessment of the tumor suppressive effect of ferrichrome in vivo. RESULTS: Ferrichrome inhibited the cell growth of colorectal cancer cells in vitro and in in vivo xenograft models. Ferrichrome exerted a strong tumor-suppressive effect that was superior to that of currently available anti-tumor agents, including 5-FU and cisplatin, both in vitro and in vivo. The tumor-suppressive effect of the combination of ferrichrome and 5-FU was superior to that of single treatment with either drug. The tumor suppressive effects of ferrichrome were confirmed through the upregulation of DDIT3 in patient-derived organoids of adenoma and carcinoma. Ferrichrome inhibited the tumor progression in the AOM-DSS model while exhibiting no anti-inflammatory effect in the DSS-colitis model, suggesting that ferrichrome inhibited cancer cells, but not a precancerous condition, via the colitis-associated pathway. CONCLUSIONS: Ferrichrome exerts a tumor suppressive effect on precancerous conditions and cancer cells associated with sporadic as well as colitis-associated colorectal cancer. The anti-tumor effect of ferrichrome was mediated by the upregulation of DDIT3, and was superior to that of 5-FU or cisplatin. These results suggest that Lactobacillus brevis-derived ferrichrome may be a candidate anti-tumor drug for the treatment of colorectal neoplasms.

Polyphosphate, Derived from Lactobacillus brevis, Modulates the Intestinal Microbiome and Attenuates Acute Pancreatitis.

BACKGROUND: We previously showed that Lactobacillus brevis-derived polyphosphate (poly P) exerts a curative effect on intestinal inflammation. However, whether or not poly P improves the inflammation and injury of distant organs remains unclear. AIMS: We aimed to investigate the change in the intestinal microbiome and to evaluate the protective effect of poly P on injuries in a cerulein-induced acute pancreatitis (AP) mouse. METHODS: Poly P was orally administered to BALB/C mice every day for 24 days, and then mice were intraperitoneally injected with cerulein. Before cerulein injection, stool samples were collected and analyzed by 16S rRNA gene sequencing. Mice were sacrificed at 24 h after the last cerulein injection; subsequently, the serum, pancreas, and colon were collected. RESULTS: The microbial profile differed markedly between poly P and control group. Notably, the levels of beneficial bacteria, including Alistipes and Candidatus_Saccharimonas, were significantly increased, while those of the virulent bacteria Desulfovibrio were decreased in the poly P group. The elevations of the serum amylase and lipase levels by cerulein treatment were suppressed by the pre-administration of poly P for 24 days, but not for 7 days. The numbers of cells MPO-positive by immunohistology were decreased and the levels of MCP-1 significantly reduced in the AP + Poly P group. An immunofluorescence analysis showed that the ZO-1 and occludin in the colon was strongly augmented in the epithelial cell membrane layer in the AP + Poly P group. CONCLUSIONS: Poly P attenuates AP through both modification of the intestinal microbiome and enhancement of the intestinal barrier integrity.

The Optimal Dose of Tacrolimus in Combination Therapy with an Anti-TNFα Antibody in a Mouse Colitis Model.

An attempt to use combination therapy with anti-tumor necrosis factor α (TNFα) antibodies and tacrolimus (TAC) has been tried to induce remission in ulcerative colitis (UC). However, the optimal dose of TAC in combination therapy with anti-TNFα antibodies (TAC + anti-TNFα therapy) remains unclear. We examined the efficacy of various doses of TAC + anti-TNFα therapy in a mouse colitis model. Dextran sulfate sodium induced colitis model mice were divided into an anti-TNFα antibody monotherapy group and the groups that received various doses of TAC + anti-TNFα therapy. The nuclear factor expression of activated T-cells, cytoplasmic 1 (NFATc1) in the nuclei and the mRNA expression of inflammatory cytokines were assessed by immunohistochemistry and RT-PCR, respectively. The serum anti-TNFα antibody concentration was measured with an enzyme-linked immunosorbent assay. The colon length and histological severity were significantly improved in the groups that received any dose of TAC + anti-TNFα therapy. The nuclear expression of NFATc1 was inversely proportional to the administered doses of TAC. The expression levels of inflammatory cytokines tended to decrease in proportion to the dose of TAC. The serum concentration of anti-TNFα antibodies in the high-dose TAC + anti-TNFα therapy was significantly higher than those in the other groups. Low-dose TAC exerted its immunosuppressive effect on T-cells, and additionally, high-dose TAC maintained the serum anti-TNFα antibody concentration. When administered in combination with anti-TNFα antibodies, the dose of TAC should be adjusted according to the disease severity.

Effect of the glycine-rich domain in GAREM2 on its unique subcellular localization upon EGF stimulation.

BACKGROUND: In mammals, there are two subtypes of Grb2-associated regulator of Erk/MAPK (GAREM), an adaptor protein that functions downstream of the cell growth factor receptor. GAREM1 is ubiquitously expressed, whereas GAREM2 is mainly expressed in the brain. However, the precise mechanism of the translocation of each GAREM subtype in growth factor-stimulated cells is still unclear. METHODS: In this study, immunofluorescence staining with specific antibodies against each GAREM subtype and time-lapse analysis using GFP fusion proteins were used to analyze the subcellular localization of each GAREM subtype in a cell growth stimulus-dependent manner. We also biochemically analyzed the correlation between its subcellular localization and tyrosine phosphorylation of GAREM2. RESULTS: We found that endogenously and exogenously expressed GAREM2 specifically aggregated and formed granules in NGF-stimulated PC-12 cells and in EGF-stimulated COS-7 cells. Based on the observed subcellular localizations of chimeric GAREM1 and GAREM2 proteins, a glycine-rich region, which is present only in GAREM2, is required for the observed granule formation. This region also regulates the degree of EGF-stimulation-dependent tyrosine phosphorylation of GAREM2. CONCLUSIONS: Our results, showing that aggregation of GAREM2 in response to EGF stimulation is dependent on a glycine-rich region, suggest that GAREM2 aggregation may be involved in neurodegenerative diseases.

Probiotic-Derived Polyphosphate Accelerates Intestinal Epithelia Wound Healing through Inducing Platelet-Derived Mediators.

Inflammatory bowel disease (IBD), such as ulcerative colitis (UC) and Crohn's disease (CD), is an intractable intestinal inflammation associated with the disruption of the intestinal mucosa. We previously demonstrated that Lactobacillus brevis-derived long-chain polyphosphate (poly P) improved the intestinal barrier function by the upregulation of cell adhesion and relieved intestinal inflammation, thereby exerting a curing effect on colitis in vitro, in vivo, and in an investigator-initiated clinical study of UC. However, how poly P improves mucosal defects induced by intestinal inflammation has not been elucidated. In this study, we detected the accumulation of platelets in inflamed tissues induced by poly P in a dextran sulfate sodium- (DSS-) induced colitis mouse model. A light transmission aggregometry analysis and scanning electron microscopy showed that poly P promoted the platelet aggregation. An SRB assay and ki-67 staining showed that the supernatant of poly P-treated platelet-rich plasma (PRP) increased intestinal epithelial cell growth. A wound healing assay showed that the supernatant of poly P-treated PRP, but not poly P itself, accelerated wound healing. A Western blotting analysis indicated that mitogen-activated protein kinase activation was induced by the supernatant of poly P-treated human PRP in the epithelial cells and its wound healing effect was significantly decreased by the inhibition of ERK signaling. These data suggested that platelet-derived mediators induced by poly P improved intestinal inflammation through the promotion of epithelial cell growth by the activation of the ERK signaling pathway. The mechanism is a novel host-microbe interaction through mammalian platelet-derived mediators induced by bacterial molecules.

Tumor-Progressive Mechanisms Mediating miRNA-Protein Interaction.

MicroRNAs (miRNAs) are single-stranded short-chain RNAs that are endogenously expressed in vertebrates; they are considered the fine-tuners of cellular protein expression that act by modifying mRNA translation. miRNAs control tissue development and differentiation, cell growth, and apoptosis in cancer and non-cancer cells. Aberrant regulation of miRNAs is involved in the pathogenesis of various diseases including cancer. Numerous investigations have shown that the changes in cellular miRNA expression in cancerous tissues and extracellular miRNAs enclosed in exosomes are correlated with cancer prognosis. Therefore, miRNAs can be used as cancer biomarkers and therapeutic targets for cancer in clinical applications. In the previous decade, miRNAs have been shown to regulate cellular functions by directly binding to proteins and mRNAs, thereby controlling cancer progression. This regulatory system implies that cancer-associated miRNAs can be applied as molecular-targeted therapy. This review discusses the roles of miRNA-protein systems in cancer progression and its future applications in cancer treatment.

Low temperature induces von-willebrand factor expression via increased early growth response 1 transcriptional activity in splenic sinusoidal endothelial cells.

von Willebrand factor (vWF) is a large plasma glycoprotein that plays an important role in hemostasis by forming molecular bridges with platelets following vascular injury. Previously, we reported that hypothermia enhanced vWF production in the spleen, which resulted in the activation of the platelet pool in a hypothermia-induced murine model. However, the mechanisms that regulate vWF expression under hypothermic conditions remain unclear. In this study, we focused on vWF expression under hypothermic conditions in splenic endothelial cell culture. Human splenic endothelial cells (HSEC) were incubated at 20 °C for 1 h. Total RNA was extracted from the cells, and cDNA microarray gene expression analysis was performed. Genes that may be associated with vWF expression in low temperature culture conditions were then selected for further analysis. Gene expression analysis showed that low temperature conditions increased the expression of FOS and EGR1. We then hypothesized that these factors upregulate vWF mRNA expression in HSEC. The transcriptional inhibitors of EGR1 significantly inhibited vWF mRNA expression in HSEC cultured at a low temperature. Our analysis revealed that low temperatures enhance the gene expression of EGR1, which transcriptionally increases vWF expression. This acute-phase reaction may play an important role in platelet activation in the spleen during hypothermia.

Acute Colchicine Poisoning Causes Endotoxemia via the Destruction of Intestinal Barrier Function: The Curative Effect of Endotoxin Prevention in a Murine Model.

BACKGROUND: Colchicine binds to intracellular tubulin and prevents mitosis. Colchicine is also used as an anti-inflammatory drug. Meanwhile, excess administration of medication or accidental ingestion of colchicine-containing plants can cause acute colchicine poisoning, which initially results in gastrointestinal effects that may be followed by multiorgan dysfunction. However, the mechanism of colchicine poisoning remains unclear, and there are no standard therapeutic strategies. AIMS: We focused on intestinal barrier function and attempted to reveal the underlying mechanism of colchicine poisoning using an animal model. METHODS: Colchicine was orally administered to C57Bl/6 mice. Then, we performed histopathological analysis, serum endotoxin assays, and intestinal permeability testing. Additionally, the LPS-TLR4 signaling inhibitor TAK-242 was intraperitoneally injected after colchicine administration to analyze the therapeutic effect. RESULTS: We observed villus height reduction and increased numbers of apoptotic cells in the gastrointestinal epithelium of colchicine-treated mice. Both intestinal permeability and serum endotoxin levels were higher in colchicine-treated mice than in control mice. Although colchicine-poisoned mice died within 25 h, those that also received TAK-242 treatment survived for more than 48 h. CONCLUSION: Colchicine disrupted intestinal barrier function and caused endotoxin shock. Therapeutic inhibition of LPS-TLR4 signaling might be beneficial for treating acute colchicine poisoning.

Heterogenous Nuclear Ribonucleoprotein H1 Promotes Colorectal Cancer Progression through the Stabilization of mRNA of Sphingosine-1-Phosphate Lyase 1.

The oncogenic properties of heterogeneous nuclear ribonucleoprotein H1 (hnRNP H1) have been reported, although the tumor-promoting mechanism remains unclear. We herein report the mechanism underlying colorectal cancer cell progression mediated by hnRNP H1. The growth of colorectal cancer cells was suppressed by hnRNP H1 downregulation. A terminal deoxynucleotidyl transferase dUTP nick-end labeling assay revealed the anti-apoptotic effect of hnRNP H1 in colorectal cancer cells. An RNA immunoprecipitation assay revealed that hnRNP H1 bound to sphingosine-1-phosphate lyase 1 (SGPL1). Reverse transcription-polymerase chain reaction revealed the high expression of hnRNP H1 mRNA in colorectal cancer cells and Spearman's rank correlation coefficient showed a strong positive correlation between hnRNP H1 mRNA and SGPL1 mRNA. An siRNA of hnRNP H1 decreased SGPL1 mRNA expression in colorectal cancer cells, but not in non-tumorous cells. These findings suggested that hnRNP H1 increased SGPL1 mRNA expression specifically in cancer cells through direct binding. Targeted knockdown of hnRNP H1 or SGPL1 with siRNAs upregulated p53 phosphorylation and p53-associated molecules, resulting in cell growth inhibition, while hnRNP H1 upregulated the mRNA of SGPL1 and inhibited p53 activation, thereby promoting tumor cell growth. This is a novel mechanism underlying colorectal cancer cell progression mediated by hnRNP H1-SGPL1 mRNA stabilization.

The effect of the 'One Stretch' exercise on the improvement of low back pain in Japanese nurses: A large-scale, randomized, controlled trial.

Objectives: To evaluate the 'One Stretch' exercise's effect on improvements in low back pain (LBP), psychological factors, and fear avoidance in a large number of nurses. Methods: Between July 2015 and June 2016, we performed a prospective, randomized, parallel-group, multi-center study with central evaluations. Eligible patients were randomly assigned (1:1:1 ratio) to either the control group (Group A) or an intervention group (Group B: 30-min seminar about the 'One Stretch' exercise, Group C: B + physical and psychological approaches to LBP treatment). The primary outcome was subjective improvement from baseline to 6 months (improved/unchanged/worsened) and overall exercise habits (good/poor). Results: There were 4767 participants: 1799, 1430, and 1548 in Groups A, B, and C, respectively. We collected data on 3439 participants (949, 706, and 751 in Groups A, B, and C, respectively) at the 6-month follow-up. The improvement rates in Groups A, B, and C were 13.3%, 23.5%, and 22.6%, respectively. The worsened pain rates were 13.0%, 9.6%, and 8.1%, which decreased as the intervention degree increased (the Cochran-Armitage trend test: p < .0001). In Groups A, B, and C, 15.6%, 64.9%, 48.8% of the patients, respectively, exhibited exercise habits. Conclusion: The 'One Stretch' exercise is useful for improving LBP.

Role of N-myristoylation in stability and subcellular localization of the CLPABP protein.

Cardiolipin and phosphatidic acid-binding protein (CLPABP) controls the stability of the mRNA harboring an AU-rich element (ARE) in the 3' UTR with the help of the RNA stabilizer, human antigen R (HuR). Although CLPABP is localized on the mitochondrial surface as a large protein-RNA complex, its precise role is not yet known. Recently, CLPABP was identified as an N-myristoylated protein. Here, we demonstrate the effects of N-myristoylation on the functions of CLPABP. In the present study, compared to the wild-type protein that possessed the "MG" motif at the N-terminus for N-myristoylation, the mutant CLPABP protein that lacked N-myristoylation modification site was unstable. Furthermore, the expression of the G/A mutant of CLPABP, which lacked N-myristoylation site, induced morphological alterations in mitochondria. Because pleckstrin homology domain-deleted mutant, which was fused with the N-myristoylation site derived from intact CLPABP, could not colocalize with mitochondria, N-myristoylation of CLPABP was predicted to affect its stability onto the mitochondrial membrane rather than its subcellular localization.

GAREM1 regulates the PR interval on electrocardiograms.

PR interval is the period from the onset of P wave to the start of the QRS complex on electrocardiograms. A recent genomewide association study (GWAS) suggested that GAREM1 was linked to the PR interval on electrocardiograms. This study was designed to validate this correlation using additional subjects and examined the function of Garem1 in a mouse model. We analyzed the association of rs17744182, a variant in the GAREM1 locus, with the PR interval in 5646 subjects who were recruited from 2 Korean replication sets, Yangpyeong (n = 2471) and Yonsei (n = 3175), and noted a significant genomewide association by meta-analysis (P = 2.39 × 10-8). To confirm the function of Garem1 in mice, Garem1 siRNA was injected into mouse tail veins to reduce the expression of Garem1. Garem1 transcript levels declined by 53% in the atrium of the heart (P = 0.029), and Garem1-siRNA injected mice experienced a significant decrease in PR interval (43.27 ms vs. 44.89 ms in control, P = 0.007). We analyzed the expression pattern of Garem1 in the heart by immunohistology and observed specific expression of Garem1 in intracardiac ganglia. Garem1 was expressed in most neurons of the ganglion, including cholinergic and adrenergic cells. We have provided evidence that GAREM1 is involved in the PR interval of ECGs. These findings increase our understanding of the regulatory signals of heart rhythm through intracardiac ganglia of the autonomic nervous system and can be used to guide the development of a therapeutic target for heart conditions, such as atrial fibrillation.

An elevated expression of serum exosomal microRNA-191, - 21, -451a of pancreatic neoplasm is considered to be efficient diagnostic marker.

BACKGROUND: Pancreatic cancer is associated with an extremely poor prognosis, so new biomarkers that can detect the initial stages are urgently needed. The significance of serum microRNA (miR) levels in pancreatic neoplasm such as pancreatic cancer and intraductal papillary mucinous neoplasm (IPMN) diagnosis remains unclear. We herein evaluated the usefulness of miRs enclosed in serum exosomes (ExmiRs) as diagnostic markers. METHODS: The ExmiRs from patients with pancreatic cancer (n = 32) or IPMN (n = 29), and patients without neoplasms (controls; n = 22) were enriched using ExoQuick-TC™. The expression of ExmiRs was evaluated using a next-generation sequencing analysis, and the selected three miRs through this analysis were confirmed by a quantitative real-time polymerase chain reaction. RESULTS: The expression of ExmiR-191, ExmiR-21 and ExmiR-451a was significantly up-regulated in patients with pancreatic cancer and IPMN compared to the controls (p < 0.05). A receiver operating characteristic curve analysis showed that the area under the curve and the diagnostic accuracy of ExmiRs were 5-20% superior to those of three serum bulky circulating miRs (e.g.; ExmiR-21: AUC 0.826, accuracy 80.8%. Circulating miR-21: AUC 0.653, accuracy 62.3%). In addition, high ExmiR-451a was associated with mural nodules in IPMN (p = 0.010), and high ExmiR-21 was identified as a candidate prognostic factor for the overall survival (p = 0.011, HR 4.071, median OS of high-ExmiR-21: 344 days, median OS of low-ExmiR-21: 846 days) and chemo-resistant markers (p = 0.022). CONCLUSIONS: The level of three ExmiRs can thus serve as early diagnostic and progression markers of pancreatic cancer and IPMN, and considered more useful markers than the circulating miRs (limited to these three miRs).