BET inhibition represses miR17-92 to drive BIM-initiated apoptosis of normal and transformed hematopoietic cells

The BET (bromodomain and extraterminal domain) bromodomain-containing proteins, such as BRD4, are highly promising targets for treating lymphoid and myeloid malignancies. They act to modulate the expression of multiple genes that control diverse cellular processes including proliferation, survival and differentiation that are consequentially disrupted by small-molecule BET bromodomain inhibitors such as JQ1. By assessing the impact of these inhibitors on normal mouse hematopoietic cells or their transformed counterparts, we establish definitively that their cytotoxic action in vitro and in vivo relies predominantly on the activation of BAX/BAK-dependent mitochondrial (intrinsic) apoptosis. In large part, this is triggered by marked upregulation of the BH3-only protein BIM when the BET inhibitors suppress miR-17-92, a key post-transcriptional repressor of BIM expression. Thus, our study strongly suggests that mutations that permit the evasion of apoptosis (for example, BCL2 overexpression, BIM inactivation) are likely to blunt the activity of the BET bromodomain inhibitors and should be anticipated when therapy resistance develops. Strikingly, we also found that certain normal hematopoietic cells, especially those of lymphoid origin, are as prone to apoptosis induced by the BET inhibitors as their transformed counterparts, indicating that their susceptibility to BET inhibitors did not arise from oncogenic transformation.

Abstract P4-04-03: Targeting of phosphatidylserine by monoclonal antibodies augments the activity of immune checkpoint inhibitor PD-1/PD-L1 therapy in murine breast tumors

Phosphatidylserine (PS) is a phospholipid that typically resides in the inner leaflet of the plasma membrane in many types of cells, including both tumor and tumor associated endothelial cells. Conditions that cause cellular stress, including those that occur from oxygen radicals, hypoxia, irradiation, and chemotherapy, cause a dramatic shift in PS localization. This change in localization results in PS shifting to the outer plasma membrane, allowing its recognition by components of the tumor microenvironment. Recognition of PS promotes an immunosuppressive environment that encourages tumor growth, in part by promoting the recruitment of myeloid derived suppressor cells, immature dendritic cells, and M2-like macrophages, in addition to inducing production of anti-inflammatory cytokines. Currently the chimeric PS-targeting antibody, bavituximab, is being used in combination with chemotherapies to treat patients with solid tumors in multiple late-stage clinical trials, where it is believe to help augment the efficacy of chemotherapeutics by blockade of PS-mediated immunosuppression and triggering an Fc-FcR mediated pro-inflammatory response in the tumor microenvironment. While the results with PS targeting therapies with chemotherapeutics are encouraging, the effectiveness of PS targeting therapies in conjunction with therapies towards immune checkpoint regulators remains largely unknown. To better understand the role of PS-targeting in breast cancers, and its effectiveness when used in combination with checkpoint inhibitors, immune competent mice harboring either EMT-6 or E0771 breast tumors were utilized. Treatments comprised PS targeting antibodies and an anti-PD1 antibody (to interrupt the PD-1/PD-L1 signaling axis) either alone or in combination with each other, and the effect on tumor growth and immune suppression determined. In both models, which showed differential sensitivity to therapy, the inclusion of PS targeting antibodies with the checkpoint blocker antibody had a significantly greater anti-tumor response than either single agent alone.

Citation Format: Gray M, Gong J, Nguyen V, Hutchins J, Freimark B. Targeting of phosphatidylserine by monoclonal antibodies augments the activity of immune checkpoint inhibitor PD-1/PD-L1 therapy in murine breast tumors. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-04-03.

Precision Measurement of the Helium Flux in Primary Cosmic Rays of Rigidities 1.9 GV to 3 TV with the Alpha Magnetic Spectrometer on the International Space Station

Knowledge of the precise rigidity dependence of the helium flux is important in understanding the origin, acceleration, and propagation of cosmic rays. A precise measurement of the helium flux in primary cosmic rays with rigidity (momentum/charge) from 1.9 GV to 3 TV based on 50 million events is presented and compared to the proton flux. The detailed variation with rigidity of the helium flux spectral index is presented for the first time. The spectral index progressively hardens at rigidities larger than 100 GV. The rigidity dependence of the helium flux spectral index is similar to that of the proton spectral index though the magnitudes are different. Remarkably, the spectral index of the proton to helium flux ratio increases with rigidity up to 45 GV and then becomes constant; the flux ratio above 45 GV is well described by a single power law.

The relation of EGFR expression by immunohistochemical staining and clinical response of combination treatment of nimotuzumab and chemotherapy in esophageal squamous cell carcinoma

INTRODUCTION

The esophageal squamous cell carcinoma (ESCC) is the predominant pathological type and accounts for more than 80 % of esophageal cancer in China. The successful use of anti-epidermal growth factor receptor (EGFR) treatment in head and neck squamous cell carcinoma provides the rationale for introducing anti-EGFR targeting treatment in ESCC. One of our prospective phase II clinical trials analyzed the efficacy of nimotuzumab, an anti-EGFR agent, combined with chemotherapy (paclitaxel and cisplatin) to treat unresectable ESCC.

MATERIALS AND METHODS

We analyzed the correlation of the clinical response with EGFR expression by immunohistochemical staining (IHC).

RESULTS

Totally 55 tumor samples were analyzed. 18/55 (32.7 %) cases were with high EGFR expression while the other 37/55 (67.3 %) cases were with low to moderate EGFR expression. The expression of EGFR was not related to gender, age, tumor location, tumor differentiation and clinical stage of disease. The objective response rate (ORR) in high EGFR expression group was 55.6 % (10/18) while that in low to moderate EGFR expression group was 54.1 % (20/37) (P = 0.57). Both the progression-free survival (PFS) and overall survival (OS) in high EGFR expression group were much shorter than those in low to moderate EGFR expression group (PFS: 5.8 ± 0.5 vs. 11.0 ± 2.8 months, P = 0.007; OS: 9.7 ± 0.5 vs. 21.5 ± 1.5 months, P = 0.03).

CONCLUSIONS

The results showed that over-expression of EGFR was related to poor survival of ESCC. The over-expression of EGFR by IHC might not be an ideal predictive biomarker of nimotuzumab treatment. Other EGFR pathway-associated molecules should be analyzed in further studies.

Precision Measurement of the Proton Flux in Primary Cosmic Rays from Rigidity 1 GV to 1.8 TV with the Alpha Magnetic Spectrometer on the International Space Station

A precise measurement of the proton flux in primary cosmic rays with rigidity (momentum/charge) from 1 GV to 1.8 TV is presented based on 300 million events. Knowledge of the rigidity dependence of the proton flux is important in understanding the origin, acceleration, and propagation of cosmic rays. We present the detailed variation with rigidity of the flux spectral index for the first time. The spectral index progressively hardens at high rigidities.

Visceral fat area is associated with a high risk for early postoperative recurrence in Crohn's disease

AIM

Mesenteric hypertrophy has been recognized as an indicator of the complicated course of Crohn's disease. The aim of this study was to investigate whether the visceral fat area (VFA) is associated with postoperative clinical and endoscopic recurrence.

METHOD

Computed tomography was used to measure the subcutaneous fat area and VFA, and the mesenteric fat index (MFI) was defined as the ratio of the VFA to the subcutaneous fat area. Associations between body mass index, subcutaneous fat area, VFA and MFI and postoperative clinical and endoscopic recurrence were investigated.

RESULTS

The factors associated with postoperative endoscopic recurrence at 6 months after surgery were a high VFA value (P = 0.019) and MFI values above the median (P = 0.008). VFA values were significantly correlated with endoscopic recurrence (r = 0.895, P = 0.040) and endoscopic lesions (r = 0.617, P < 0.0001). Additionally, MFI values correlated well with endoscopic recurrence (r = 0.918, P = 0.02) and endoscopic scores (r = 0.584, P < 0.0001). Multivariate analysis indicated that VFA values above the median (hazard ratio 2.63, 95% CI 1.03-6.74) were predictive of postoperative clinical recurrence in Crohn's disease.

CONCLUSION

A high VFA value is associated with postoperative recurrence of Crohn's disease and has clinical implications with respect to optimizing prophylaxis for each individual. However, further studies are needed to confirm the predictive role of this biomarker in a different data set.

Precision Measurement of the (e^{+}+e^{-}) Flux in Primary Cosmic Rays from 0.5 GeV to 1 TeV with the Alpha Magnetic Spectrometer on the International Space Station

We present a measurement of the cosmic ray (e^{+}+e^{-}) flux in the range 0.5 GeV to 1 TeV based on the analysis of 10.6 million (e^{+}+e^{-}) events collected by AMS. The statistics and the resolution of AMS provide a precision measurement of the flux. The flux is smooth and reveals new and distinct information. Above 30.2 GeV, the flux can be described by a single power law with a spectral index γ=-3.170±0.008(stat+syst)±0.008(energy scale).

Stapled vs hand suture closure of loop ileostomy: a meta-analysis

AIM

Loop ileostomies are widely used in colorectal surgery to reduce the consequences of distal anastomotic failure. The optimal surgical technique for their closure has yet not been defined. A meta-analysis was performed to compare the outcome after stapled or hand sutured ileostomy closure.

METHOD

An electronic literature search of EMBASE, PubMed and the Cochrane Library was undertaken to identify studies reporting stapled and hand sutured ileostomy closure. End-points included postoperative small bowel obstruction (SBO), anastomotic leakage, wound infection, overall postoperative complications, operation time, hospital stay and surgery-related cost.

RESULTS

Fourteen studies including 5084 patients were identified. Meta-analysis showed that stapled closure was associated with a lower rate of SBO overall (OR = 0.56, P < 0.00001) and early (within 30 days of closure) SBO (OR = 0.51, P < 0.00001). This difference persisted for direct ileostomy closure (OR = 0.62, P = 0.02) or closure with bowel resection and hand sewn anastomosis (OR = 0.44, P < 0.00001). Stapled closure required a shorter inpatient stay (mean difference -1.22, P < 0.0001) and operating time (mean difference -11.21, P = 0.01). No significant difference was noted between the two techniques in terms of anastomotic leakage, wound infection, overall complications or cost.

CONCLUSION

Stapled side-to-side anastomosis is associated with fewer complications, especially SBO, than hand sewn ileostomy closure by direct suture or resection and anastomosis. It is quicker to perform and associated with fewer postoperative bowel obstructions.

Detection of Salmonella spp. by a loop-mediated isothermal amplification (LAMP) method targeting bcfD gene

In this study, we developed and validated a loop-mediated isothermal amplification (LAMP) assay for Salmonella detection targeting bcfD gene, a conserved fimbrial operon gene existing in Salmonella. The Salmonella LAMP assay we developed successfully amplified 44 Salmonella strains (14 standard strains and 30 clinical isolates), but none of 9 non-Salmonella standard strains (Proteus mirabilis, Listeria monocytogenes, Escherichia coli, Pseudomonas aeruginosa, Shigella flexneri, Shigella sonnei, Klebsiella pneumoniae, Campylobacter jejuni and Vibrio parahemolyticus). The detection limit was 5 CFU of Salmonella pure culture or 200 CFU of artificially spiked faeces per reaction system (equivalent to 5000 CFU g(-1) of faeces), and this method could directly detect Salmonella in chicken faeces free of pre-enrichment in a reaction time of 25 min. Our experiments show that the LAMP method we developed is a rapid, sensitive, specific and practical method for Salmonella detection. The Salmonella LAMP assay can potentially serve as new on-site diagnostics in the food and agricultural industries.

SIGNIFICANCE AND IMPACT OF THE STUDY

A loop-mediated isothermal amplification (LAMP) assay was established to detect Salmonella targeting bcfD gene, a conserved fimbrial operon gene. The detection limit was 5 CFU of Salmonella pure culture or 200 CFU of artificially spiked faeces per reaction system (equivalent to 5000 CFU g(-1) of faeces), and this method could directly detect Salmonella in chicken faeces free of pre-enrichment in a reaction time of 25 min. The Salmonella LAMP assay is a rapid, sensitive, specific and practical method for Salmonella detection and can potentially serve as new on-site diagnostics in the food and agricultural industries.

Electron and positron fluxes in primary cosmic rays measured with the alpha magnetic spectrometer on the international space station

Precision measurements by the Alpha Magnetic Spectrometer on the International Space Station of the primary cosmic-ray electron flux in the range 0.5 to 700 GeV and the positron flux in the range 0.5 to 500 GeV are presented. The electron flux and the positron flux each require a description beyond a single power-law spectrum. Both the electron flux and the positron flux change their behavior at ∼30  GeV but the fluxes are significantly different in their magnitude and energy dependence. Between 20 and 200 GeV the positron spectral index is significantly harder than the electron spectral index. The determination of the differing behavior of the spectral indices versus energy is a new observation and provides important information on the origins of cosmic-ray electrons and positrons.

High statistics measurement of the positron fraction in primary cosmic rays of 0.5-500 GeV with the alpha magnetic spectrometer on the international space station

A precision measurement by AMS of the positron fraction in primary cosmic rays in the energy range from 0.5 to 500 GeV based on 10.9 million positron and electron events is presented. This measurement extends the energy range of our previous observation and increases its precision. The new results show, for the first time, that above ∼200  GeV the positron fraction no longer exhibits an increase with energy.

Oral treatment with SEW2871, a sphingosine-1-phosphate type 1 receptor agonist, ameliorates experimental colitis in interleukin-10 gene deficient mice

SEW2871, a selective sphingosine-1-phosphate type 1 receptor (S1P1) agonist, has been shown to be effective in protecting kidneys against ischaemia-reperfusion injury by reducing CD4(+) T cell infiltration in mice. However, the effects of SEW2871 on colitis remain unclear. The aim of this study was to investigate the effects of SEW2871 on established colitis in interleukin (IL)-10 gene-deficient (IL-10(-/-)) mice, a murine model of Crohn's disease (CD). SEW2871 was administered by gavage at a dose of 20 mg/kg/day for 2 weeks to IL-10(-/-) mice. Severity of colitis, serum amyloid A, tissue myeloperoxidase (MPO), T cells in blood and colon lamina propria (LP) and proinflammatory cytokine productions were evaluated. Furthermore, the phospho-signal transducer and activator of transcription (STAT)-3 (p-STAT-3) expression in lymphocytes isolated from colon LP was also assessed. The 2-week administration of SEW2871 ameliorated established colitis in IL-10(-/-) mice, associated with a reduction of serum amyloid A concentration, a decreased colon MPO concentration, a depletion of the peripheral CD4(+) CD45(+) T cells and a reduction of the homing of T cells into colon LP. Moreover, typical cytokines of T helper type 1 (Th1) and Th17 cells and p-STAT-3 expression were also suppressed by SEW2871 treatment. SEW2871 treatment ameliorates established experimental colitis in IL-10(-/-) mice, which may provide a new therapeutic approach for human CD therapy.

Review: Chinese herbs as alternatives to antibiotics in feed for swine and poultry production: Potential and challenges in application

Gong, J., Yin, F., Hou, Y. and Yin, Y. 2014. Chinese herbs as alternatives to antibiotics in feed for swine and poultry production: Potential and challenges in application. Can. J. Anim. Sci. 94: 223–241. Traditional Chinese medicine (TCM) has a long history of clinical practice, and its own theoretical framework focused on functions at the whole-body level. However, due to cultural differences, TCM has not been fully recognized in Western countries. With the recent development of the theory of whole-body systems biology and “-omics”, there is a new opportunity to study TCM and to close the gap between TCM and Western medicine, because of the similarity in the theoretical foundations between TCM and whole-body systems biology. The uniqueness of TCM theory and practice is the approach to maintain and restore the body balance as a whole with no or little unfavourable side effects. Recent studies have also shown that Chinese herbs used as feed additives can modulate nutritional metabolism, immune responses, and intestinal health of food-producing animals, demonstrating good potential as substitutes for dietary antibiotics. Nonetheless, some issues need to be addressed before Chinese herbs can reach their full application. This article has critically reviewed recent progresses in scientific research of Chinese herbs as feed additives and their potential to replace dietary antibiotics. Possible challenges in future application for swine and poultry production are also discussed.

Investigation into in vitro and in vivo models using intestinal epithelial IPEC-J2 cells and Caenorhabditis elegans for selecting probiotic candidates to control porcine enterotoxigenic Escherichia coli

AIMS

To identify a fast, economic and reliable method for preselecting lactic acid-producing bacterial (LAB) isolates to control enterotoxigenic Escherichia coli (ETEC).

METHODS AND RESULTS

Two assays with porcine intestinal epithelial IPEC-J2 cells or Caenorhabditis elegans for selecting effective probiotic candidates were compared. Both assays were based on measuring death of cells or worms caused by ETEC strain JG280. Six of 13 LAB isolates showed ≥50% protection in each assay, among which only four isolates (≥50% protection) were consistently selected by both assays. Isolate CL9 (Lactobacillus reuteri) was further studied. It reduced gene expression of estA, estB and elt in JG280 in both assays. Furthermore, the isolate protected IPEC-J2 and C. elegans from cell and worm death caused by STa, STb or LT enterotoxin expressed in E. coli DH5α. CL9 also promoted host defensive responses by decreasing IL-8 and increasing IL-10 production in IPEC-J2 cells and expression of antimicrobial peptide genes clec-60, clec-85 in C. elegans.

CONCLUSIONS

Caenorhabditis elegans is useful for preselecting probiotic candidates to control ETEC after initial screening with IPEC-J2 cells.

SIGNIFICANCE AND IMPACT OF THE STUDY

A combination of IPEC-J2 cell and C. elegans assays can improve the effectiveness in preselecting probiotic candidates.

Vitamin D with asthma and COPD: not a false hope? A systematic review and meta-analysis

Vitamin D deficiency and insufficiency are increasingly being recognized in the general population over the last few decades. However, a number of other disorders have now been linked to vitamin D deficiency and insufficiency, including asthma and COPD. The aim of this study was to evaluate the evidence on the effect of vitamin D on asthma and COPD. We searched electronic databases including SCI, EMBASE, Ovid, and PubMed. Reviewers working independently and in duplicate extracted study characteristics, quality, and the outcomes. The weighted mean differences across trials and random-effect meta-analysis were used to pool the relative risks (RR). This is the first meta-analysis about the risk of vitamin D deficiency for asthma and COPD. Ten studies were available for this meta-analysis and systematic review. The prevalence of vitamin D deficiency was significantly greater among cases than control subjects [RR=1.59, 95%CI=1.07-2.36, 488/812 (60%) vs 278/875 (32%)] for asthma. However, vitamin D insufficiency was not significantly associated with asthma [RR=1.09, 95%CI=0.91-1.30, 702/996 (70%) vs 665/1016 (65%)]. Moreover, studies failed to demonstrate that COPD patients had an increased risk for vitamin D deficiency or insufficiency compared to controls (RR=0.89, 95%CI=0.63-1.25). Vitamin D deficiency was associated with a significant decrease in lung function in asthmatic children. Vitamin D deficiency was highly prevalent in asthma patients, and vitamin D status was associated with lung function. COPD cannot be considered as completely free of vitamin D deficiency.