Dualistic Effects of PRKAR1A as a Potential Anticancer Target in Cancer Cells and Cancer-Derived Stem Cells

The integration of innovative medical technologies and interdisciplinary collaboration could improve the treatment of cancer, a globally prevalent and often deadly disease. Despite recent advancements, current cancer therapies fail to specifically address recurrence and target cancer stem cells (CSCs), which contribute to relapse. In this study, we utilized three types of cancer cells, from which three types of CSCs were further derived, to conduct a proteomic analysis. Additionally, shared cell surface biomarkers were identified as potential targets for a comprehensive treatment strategy. The selected biomarkers were evaluated through short hairpin RNA treatment, which revealed contrasting functions in cancer cells and CSCs. Knockdown of the identified proteins revealed that they regulate the epithelial-mesenchymal transition (EMT) and stemness via the ERK signaling pathway. Resistance to anticancer agents was consequently reduced, ultimately enhancing the overall anticancer effects of the treatment. Additionally, the significance of these biomarkers in clinical patient outcomes was confirmed using bioinformatics. Our study suggests a novel cancer treatment strategy that addresses the limitations of current anticancer therapies.

Active Targeting of Versatile Nanocomplex Using the Novel Biomarker of Breast Cancer Stem Cells

Breast cancer in women is one of the most common life-threatening malignancies. Despite of the development for the improved treatment, there are still many limitations to overcome. Among them, cancer stem cells (CSCs) are well known for tumor formation, development, cellular heterogeneity, and cancer recurrence. Therefore, to completely cure breast cancer, treatment of both cancer and CSC is required. To selectively target CSCs, we generated a liposome-based smart nano complex using CEACAM 6 (CD66c) antibody (Ab), a novel cell-surface biomarker of breast-derived CSCs (BCSCs) discovered in our previous research. Selective and increased cellular uptake was observed in BCSCs treated with CD66c Ab-conjugated rhodamine-labeled liposomes (CDRHOL) depending on the expression level of CD66c. CD66c Ab-conjugated doxorubicin (DOX)-loaded liposomes (CDDOXL) selectively showed increased cell killing effects in BCSCs with high CD66c expression levels. In an in vivo animal study, CDRHOL showed enhanced accumulation in xenografted BCSC tumors with low delivery into non-target organs. Moreover, mice treated with CDDOXL have assessed the decreased induction ability of immune response by low expression levels of pro-inflammatory cytokines and reduced liver toxicity by histopathological analysis. Finally, the improved antitumor effect of CDDOXL was evaluated in a metastatic BCSC mouse model via systemic administration. Collectively, our study is the first to demonstrate that a multi-functional nano complex using a novel surface biomarker of BCSC may be a more effective therapeutic agent for the treatment of cancer and CSCs.

Polycystin-1 Enhances Stemmness Potential of Umbilical Cord Blood-Derived Mesenchymal Stem Cells

Polycystic Kidney Disease (PKD) is a disorder that affects the kidneys and other organs, and its major forms are encoded by polycystin-1 (PC1) and polycystin-2 (PC2), as PKD1 and PKD2. It is located sandwiched inside and outside cell membranes and interacts with other cells. This protein is most active in kidney cells before birth, and PC1 and PC2 work together to help regulate cell proliferation, cell migration, and interactions with other cells. The molecular relationship and the function between PKD1 and cancer is well known, such as increased or decreased cell proliferation and promoting or suppressing cell migration depending on the cancer cell type specifically. However, its function in stem cells has not been revealed. Therefore, in this study, we investigated the biological function of PC1 and umbilical cord blood-derived mesenchymal stem cell (UCB-MSC). Furthermore, we assessed how it affects cell migration, proliferation, and the viability of cells when expressed in the PKD1 gene. In addition, we confirmed in an ex vivo artificial tooth model generated by the three-dimension printing technique that the ability to differentiate into osteocytes improved according to the expression level of the stemness markers when PKD1 was expressed. This study is the first report to examine the biological function of PKD1 in UCB-MSC. This gene may be capable of enhancing differentiation ability and maintaining long-term stemness for the therapeutic use of stem cells.

The Effect of Annexin A1 as a Potential New Therapeutic Target on Neuronal Damage by Activated Microglia

Brain disease is known to cause irrevocable and fatal loss of biological function once damaged. One of various causes of its development is damage to neuron cells caused by hyperactivated microglia, which function as immune cells in brain. Among the genes expressed in microglia stimulated by various antigens, annexin A1 (ANXA1) is expressed in the early phase of the inflammatory response and plays an important role in controlling the immune response. In this study, we assessed whether ANXA1 can be a therapeutic target gene for the initial reduction of the immune response induced by microglia to minimize neuronal damage. To address this, mouse-origin microglial cells were stimulated to mimic an immune response by lipopolysaccharide (LPS) treatment. The LPS treatment caused activation of ANXA1 gene and expression of inflammatory cytokines. To assess the biological function in microglia by the downregulation of ANXA1 gene, cells were treated with short hairpin RNA-ANXA1. Downregulated ANXA1 affected the function of mitochondria in the microglia and showed reduced neuronal damage when compared to the control group in the co-culture system. Taken together, our results showed that ANXA1 could be used as a potential therapeutic target for inflammation-related neurodegenerative diseases.

Safety and efficacy of transarterial embolisation for treatment of dorsal pancreatic artery haemorrhage

AIM

To evaluate the safety and efficacy of transarterial embolisation (TAE) of dorsal pancreatic artery (DPA) haemorrhage.

MATERIALS AND METHODS

Nineteen consecutive patients (M:F = 16:3, mean age 59.6 years) who underwent TAE of DPA in three tertiary medical centres between January 2001 to January 2020 were reviewed retrospectively. Angiographic features and the technical and clinical outcomes of TAE were analysed.

RESULTS

The clinical presentations were a bloody drain from the Jackson-Pratt drainage tube (n=8), melaena (n=7), abdominal pain (n=4), and haematochezia (n=3). Angiographic findings included pseudoaneurysm (n=14), contrast media extravasation (n=4), or abrupt cut-off of the arterial branch (n=1). The NBCA (N-butyl-cyanoacrylate; n=4), microcoils (n=4), and a combination of these agents (n=7) were used as embolic agents. The most common origin of the DPA in the present study cohort was the splenic artery (n=7), followed by the coeliac trunk (n=4), common hepatic artery (n=4), and superior mesenteric artery (n=4). Technical and clinical success rates were 100% and 84.2% (16/19), respectively. Of the three clinically unsuccessful cases, two patients were revealed to have newly developed bleeding from another artery. The other patient expired 1 day after the TAE procedure due to a progression of hepatic failure. In one patient, an asymptomatic non-target embolisation occurred in the right posterior tibial artery as a procedure-related complication. No major complications were observed.

CONCLUSION

TAE is safe and effective for the management of bleeding from the DPA. It is important to be aware of the DPA as a potential bleeding source, including the relevant clinical characteristics.

Observation of Bistable Turbulence in Quasi-Two-Dimensional Superflow

Turbulent flow restricted to two dimensions can spontaneously develop order on large scales, defying entropy expectations and in sharp contrast with turbulence in three dimensions where nonlinear turbulent processes act to destroy large-scale order. In this work we report the observation of unusual turbulent behavior in steady-state flow of superfluid ^{4}He-a liquid with vanishing viscosity and discrete vorticity-in a nearly two-dimensional channel. Surprisingly, for a range of experimental parameters, turbulence is observed to exist in two bistable states. This bistability can be well explained by the appearance of large-scale regions of flow of opposite vorticity.

Biological Functions and Identification of Novel Biomarker Expressed on the Surface of Breast Cancer-Derived Cancer Stem Cells via Proteomic Analysis

Breast cancer is one of the most common life-threatening malignancies and the top cause of cancer deaths in women. Although many conventional therapies exist for its treatment, breast cancer still has many handicaps to overcome. Cancer stem cells (CSCs) are a well-known cause of tumor recurrences due to the ability of CSCs for self-renewal and differentiation into cell subpopulations, similar to stem cells. To fully treat breast cancer, a strategy for the treatment of both cancer cells and CSCs is required. However, current strategies for the eradication of CSCs are non-specific and have low efficacy. Therefore, surface biomarkers to selectively treat CSCs need to be developed. Here, 34 out of 641 surface biomarkers on CSCs were identified by proteomic analysis between the human breast adenocarcinoma cell line MCF-7 and MCF-7-derived CSCs. Among them, carcinoembryonic antigen-related cell adhesion molecules 6 (CEACAM6 or CD66c), a member of the CEA family, was selected as a novel biomarker on the CSC surface. This biomarker was then experimentally validated and evaluated for use as a CSC-specific marker. Its biological effects were assessed by treating breast cancer stem cells (BCSCs) with short hairpin (sh)-RNA under oxidative cellular conditions. This study is the first to evaluate the biological function of CD66c as a novel biomarker on the surface of CSCs. This marker is available as a moiety for use in the development of targeted therapeutic agents against CSCs.

Stabilized Pair Density Wave via Nanoscale Confinement of Superfluid ^{3}He

Superfluid ^{3}He under nanoscale confinement has generated significant interest due to the rich spectrum of phases with complex order parameters that may be stabilized. Experiments have uncovered a variety of interesting phenomena, but a complete picture of superfluid ^{3}He under confinement has remained elusive. Here, we present phase diagrams of superfluid ^{3}He under varying degrees of uniaxial confinement, over a wide range of pressures, which elucidate the progressive stability of both the A phase, as well as a growing region of stable pair density wave state.

IFN-γ enhances the wound healing effect of late EPCs (LEPCs) via BST2-mediated adhesion to endothelial cells

Circulating late endothelial progenitor cells (LEPCs) home to injured vessels, initiating blood vessel regeneration. This process requires the initial adhesion of LEPCs to endothelial cells within the wounded site. In this study, treating LEPCs with IFN-γ enhanced wound healing through BST2-mediated adhesion to endothelial cells. We found that IFN-γ significantly upregulated BST2 expression in both LEPCs and ECs and increased tube formation in LEPCs. Upregulated BST2 increased LEPC adhesion to ECs through a tight homophilic interaction of its extracellular domain. Finally, when the IFN-γ-treated LEPCs were injected into the wounded mouse tail vein, superior therapeutic effects of wound closure were observed. This study provides a useful application to enhance the adhesion of LEPCs for vessel regeneration and wound closure.

Clinical outcomes of 23 patients who had repeat pelvic arterial embolisation for uncontrolled post-partum haemorrhage at a single centre

AIM

To evaluate the safety and efficacy of repeated pelvic arterial embolisation (PAE) for uncontrolled postpartum haemorrhage (PPH) after a single session of PAE and to compare angiographic findings between the two sessions of PAE.

MATERIALS AND METHODS

A total of 23 consecutive patients (age range, 23-44 years) who underwent repeated PAE for uncontrolled PPH between March 2001 and January 2016 in Severance Hospital were reviewed. The interval times between the two sessions of PAE, the angiographic findings, embolic materials, arteries embolised during PAE, and the clinical outcomes were reviewed retrospectively.

RESULTS

Overall clinical success was achieved after repeated PAE in 21 of 23 patients (91.3%). There were no procedure-related, major complications. On angiography, active bleeding from the uterine collateral arteries was more frequently observed in the second session of PAE (p>0.05), and embolisation of the anterior division of the internal iliac artery was significantly higher during the second session of PAE. Use of permanent embolic materials was significantly higher during the second session of PAE. Recanalisation of a previously embolised artery was identified in 14 patients (60.9%) during the second session.

CONCLUSION

Repeated PAE is safe and effective for managing recurrent bleeding after a single session of PAE. Repeated PAE is related to a higher chance of embolisation of the anterior division of the internal iliac artery, with the use of permanent embolic materials. Recanalisation of a previously embolised artery seems to be a principal source of rebleeding during a repeated session of PAE.

Magnetic actuation and feedback cooling of a cavity optomechanical torque sensor

Cavity optomechanics has demonstrated remarkable capabilities, such as measurement and control of mechanical motion at the quantum level. Yet many compelling applications of optomechanics—such as microwave-to-telecom wavelength conversion, quantum memories, materials studies, and sensing applications—require hybrid devices, where the optomechanical system is coupled to a separate, typically condensed matter, system. Here, we demonstrate such a hybrid optomechanical system, in which a mesoscopic ferromagnetic needle is integrated with an optomechanical torsional resonator. Using this system we quantitatively extract the magnetization of the needle, not known a priori, demonstrating the potential of this system for studies of nanomagnetism. Furthermore, we show that we can magnetically dampen its torsional mode from room-temperature to 11.6 K—improving its mechanical response time without sacrificing torque sensitivity. Future extensions will enable studies of high-frequency spin dynamics and broadband wavelength conversion via torque mixing.

Although optomechanics enables precision metrology, measurements beyond mechanical properties often require hybrid devices. Here, Kim et al. demonstrate that a ferromagnetic needle integrated with a torsional resonator can determine the magnetic properties and amplify or cool the resonator motion.

Hedgehog-Interacting Protein (HIP) Regulates Apoptosis Evasion and Angiogenic Function of Late Endothelial Progenitor Cells

Late endothelial progenitor cells (LEPCs) are derived from mononuclear cells (MNCs) and are thought to directly incorporate into blood vessels and differentiate into mature endothelial cells (ECs). Using transcriptome and proteome analysis, we identified distinctive LEPC profiles and found that Hedgehog-interacting protein (HIP) is strongly expressed in LEPCs. Inhibition of HIP by lentiviral knockdown activated canonical hedgehog signaling in LEPCs, while it activated non-canonical hedgehog signaling in ECs. In LEPCs, HIP knockdown induced much enhanced tube formation and resistance to apoptosis under oxidative stress conditions via canonical hedgehog signaling. Although HIP is strongly expressed in proliferating LEPCs, HIP expression is down-regulated during angiogenesis and under oxidative stress condition. Moreover, when LEPCs are treated with angiogenic triggers such as VEGF and FGF2, HIP expression is reduced. Our findings suggest that HIP blocks LEPC angiogenesis and regulate survival when there is no angiogenic stimulation. HIP inhibition in LEPCs enhanced tube formation and reduced apoptosis, resulting in improved angiogenesis.

Targeted Genome Engineering to Control VEGF Expression in Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells: Potential Implications for the Treatment of Myocardial Infarction

Human umbilical cord blood‐derived mesenchymal stem cells (hUCB‐MSCs) exhibit potency for the regeneration of infarcted hearts. Vascular endothelial growth factor (VEGF) is capable of inducing angiogenesis and can boost stem cell‐based therapeutic effects. However, high levels of VEGF can cause abnormal blood vessel growth and hemangiomas. Thus, a controllable system to induce therapeutic levels of VEGF is required for cell therapy. We generated an inducible VEGF‐secreting stem cell (VEGF/hUCB‐MSC) that controls the expression of VEGF and tested the therapeutic efficacy in rat myocardial infarction (MI) model to apply functional stem cells to MI. To introduce the inducible VEGF gene cassette into a safe harbor site of the hUCB‐MSC chromosome, the transcription activator‐like effector nucleases system was used. After confirming the integration of the cassette into the locus, VEGF secretion in physiological concentration from VEGF/hUCB‐MSCs after doxycycline (Dox) induction was proved in conditioned media. VEGF secretion was detected in mice implanted with VEGF/hUCB‐MSCs grown via a cell sheet system. Vessel formation was induced in mice transplanted with Matrigel containing VEGF/hUCB‐MSCs treated with Dox. Moreover, seeding of the VEGF/hUCB‐MSCs onto the cardiac patch significantly improved the left ventricle ejection fraction and fractional shortening in a rat MI model upon VEGF induction. Induced VEGF/hUCB‐MSC patches significantly decreased the MI size and fibrosis and increased muscle thickness, suggesting improved survival of cardiomyocytes and protection from MI damage. These results suggest that our inducible VEGF‐secreting stem cell system is an effective therapeutic approach for the treatment of MI. Stem Cells Translational Medicine2017;6:1040–1051

Approaching the standard quantum limit of mechanical torque sensing

Reducing the moment of inertia improves the sensitivity of a mechanically based torque sensor, the parallel of reducing the mass of a force sensor, yet the correspondingly small displacements can be difficult to measure. To resolve this, we incorporate cavity optomechanics, which involves co-localizing an optical and mechanical resonance. With the resulting enhanced readout, cavity-optomechanical torque sensors are now limited only by thermal noise. Further progress requires thermalizing such sensors to low temperatures, where sensitivity limitations are instead imposed by quantum noise. Here, by cooling a cavity-optomechanical torque sensor to 25 mK, we demonstrate a torque sensitivity of 2.9 yNm/. At just over a factor of ten above its quantum-limited sensitivity, such cryogenic optomechanical torque sensors will enable both static and dynamic measurements of integrated samples at the level of a few hundred spins.

Cavity optomechanics enables measurement of torque at levels unattainable by previous techniques, but the main obstacle to improved sensitivity is thermal noise. Here the authors present cryogenic measurement of a cavity-optomechanical torsional resonator with unprecedented torque sensitivity of 2.9 yNm/√Hz.

Myocardial tissue engineering using electrospun nanofiber composites

Emerging trends for cardiac tissue engineering are focused on increasing the biocompatibility and tissue regeneration ability of artificial heart tissue by incorporating various cell sources and bioactive molecules. Although primary cardiomyocytes can be successfully implanted, clinical applications are restricted due to their low survival rates and poor proliferation. To develop successful cardiovascular tissue regeneration systems, new technologies must be introduced to improve myocardial regeneration. Electrospinning is a simple, versatile technique for fabricating nanofibers. Here, we discuss various biodegradable polymers (natural, synthetic, and combinatorial polymers) that can be used for fiber fabrication. We also describe a series of fiber modification methods that can increase cell survival, proliferation, and migration and provide supporting mechanical properties by mimicking micro-environment structures, such as the extracellular matrix (ECM). In addition, the applications and types of nanofiber-based scaffolds for myocardial regeneration are described. Finally, fusion research methods combined with stem cells and scaffolds to improve biocompatibility are discussed. [BMB Reports 2016; 49(1): 26-36]

Stanniocalcin 2 enhances mesenchymal stem cell survival by suppressing oxidative stress

To overcome the disadvantages of stem cell-based cell therapy like low cell survival at the disease site, we used stanniocalcin 2 (STC2), a family of secreted glycoprotein hormones that function to inhibit apoptosis and oxidative damage and to induce proliferation. STC2 gene was transfected into two kinds of stem cells to prolong cell survival and protect the cells from the damage by oxidative stress. The stem cells expressing STC2 exhibited increased cell viability and improved cell survival as well as elevated expression of the pluripotency and self-renewal markers (Oct4 and Nanog) under sub-lethal oxidative conditions. Up-regulation of CDK2 and CDK4 and down-regulation of cell cycle inhibitors p16 and p21 were observed after the delivery of STC2. Furthermore, STC2 transduction activated pAKT and pERK 1/2 signal pathways. Taken together, the STC2 can be used to enhance cell survival and maintain long-term stemness in therapeutic use of stem cells. [BMB Reports 2015; 48(12): 702-707]

Galactosylated Liposomes for Targeted Co-Delivery of Doxorubicin/Vimentin siRNA to Hepatocellular Carcinoma

The combination of therapeutic nucleic acids and chemotherapeutic drugs has shown great promise for cancer therapy. In this study, asialoglycoprotein receptors (ASGPR) targeting-ligand-based liposomes were tested to determine whether they can co-deliver vimentin siRNA and doxorubicin to hepatocellular carcinoma (HCC) selectively. To achieve this goal, we developed an ASGPR receptor targeted co-delivery system called gal-doxorubicin/vimentin siRNA liposome (Gal-DOX/siRNA-L). The Gal-DOX/siRNA-L was created via electrostatic interaction of galactose linked-cationic liposomal doxorubicin (Gal-DOX-L) on vimentin siRNA. Previous studies have shown that Gal-DOX/siRNA-L inhibited tumor growth by combined effect of DOX and vimentin siRNA than single delivery of either DOX or vimentin siRNA. These Gal-DOX/siRNA-Ls showed stronger affinity to human hepatocellular carcinoma cells (Huh7) than other cells (lung epithelial carcinoma, A549). These liposomes also have demonstrated that novel hepatic drug/gene delivery systems composed of cationic lipid (DMKE: O,O'-dimyristyl-N-lysyl glutamate), cholesterol, galactosylated ceramide, POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine), and PEG₂₀₀₀-DSPE (distearoyl phosphatidyl ethanolamine) at 2:1:1:1:0.2 (moral ratios) can be used as an effective drug/gene carrier specifically targeting the liver in vivo. These results suggest that Gal-DOX-siRNA-L could effectively target tumor cells, enhance transfection efficacy and subsequently achieve the co-delivery of DOX and siRNA, demonstrating great potential for synergistic anti-tumor therapy.

Inducible HGF-secreting Human Umbilical Cord Blood-derived MSCs Produced via TALEN-mediated Genome Editing Promoted Angiogenesis

Mesenchymal stem cells (MSCs) promote therapeutic angiogenesis to cure serious vascular disorders. However, their survival period and cytokine-secretory capacity are limited. Although hepatocyte growth factor (HGF) can accelerate the rate of angiogenesis, recombinant HGF is limited because of its very short half-life (<3–5 minutes). Thus, continuous treatment with HGF is required to obtain an effective therapeutic response. To overcome these limitations, we produced genome-edited MSCs that secreted HGF upon drug-specific induction. The inducible HGF expression cassette was integrated into a safe harbor site in an MSC chromosome using the TALEN system, resulting in the production of TetOn-HGF/human umbilical cord blood-derived (hUCB)-MSCs. Functional assessment of the TetOn-HGF/hUCB-MSCs showed that they had enhanced mobility upon the induction of HGF expression. Moreover, long-term exposure by doxycycline (Dox)-treated TetOn-HGF/hUCB-MSCs enhanced the anti-apoptotic responses of genome-edited MSCs subjected to oxidative stress and improved the tube-formation ability. Furthermore, TetOn-HGF/hUCB-MSCs encapsulated by arginine-glycine-aspartic acid (RGD)-alginate microgel induced to express HGF improved in vivo angiogenesis in a mouse hindlimb ischemia model. This study showed that the inducible HGF-expressing hUCB-MSCs are competent to continuously express and secrete HGF in a controlled manner. Thus, the MSCs that express HGF in an inducible manner are a useful therapeutic modality for the treatment of vascular diseases requiring angiogenesis.

Optical microscope and tapered fiber coupling apparatus for a dilution refrigerator

We have developed a system for tapered fiber measurements of optomechanical resonators inside a dilution refrigerator, which is compatible with both on- and off-chip devices. Our apparatus features full three-dimensional control of the taper-resonator coupling conditions enabling critical coupling, with an overall fiber transmission efficiency of up to 70%. Notably, our design incorporates an optical microscope system consisting of a coherent bundle of 37,000 optical fibers for real-time imaging of the experiment at a resolution of ∼1 μm. We present cryogenic optical and optomechanical measurements of resonators coupled to tapered fibers at temperatures as low as 9 mK.

Outcomes in patients undergoing nephrectomy for renal cancer on chronic anticoagulation therapy

AIMS

To report our experience on surgical resection of renal tumors for patients with a history of chronic anticoagulation (ACT) or aspirin use.

METHODS

We performed a retrospective analysis of 2473 patients who underwent surgery for renal tumors between 2005 and 2012. Prior to surgery, 172 were on chronic ACT and 695 on aspirin. Multivariable linear and logistic regression models were used to compare transfusion and overall complication rates between patients undergoing renal surgery who were on therapy to patients who were on aspirin and to patients with no therapy.

RESULTS

Compared to no therapy and aspirin patients those on ACT were older (57.3 (IQR 48.4-66.10) vs 63.9, (IQR 57.3-71.5) vs 68.4, (IQR 60.4-73.5); p < 0.001), with a higher percentage having an ASA score of 3 or 4 (42.4 vs 57.9 vs 82.6%; p < 0.001), respectively. ACT patients had a higher 30-day transfusion rate, 22.7% vs 7.6% vs 6.9%, and 90-day complication rate, 17.4% vs 7.2% vs 7.3%, both p < 0.001. The median length of stay differed statistically between groups (p < 0.001), with a modest longer stay in the anticoagulation group (OR 1.11 SE 0.26; p < 0.001). Transfusion and complication rates for patients on therapy undergoing minimally invasive surgery vs open surgery were not statistically different.

CONCLUSIONS

Patients on chronic ACT had higher transfusion and overall complication rates compared to patients on no treatment or on chronic aspirin. These findings did not correlate to clinical differences in length of stay or grade 3-5 complications.

Separated response function ratios in exclusive, forward π(±) electroproduction

The study of exclusive π(±) electroproduction on the nucleon, including separation of the various structure functions, is of interest for a number of reasons. The ratio RL=σL(π-)/σL(π+) is sensitive to isoscalar contamination to the dominant isovector pion exchange amplitude, which is the basis for the determination of the charged pion form factor from electroproduction data. A change in the value of RT=σT(π-)/σT(π+) from unity at small -t, to 1/4 at large -t, would suggest a transition from coupling to a (virtual) pion to coupling to individual quarks. Furthermore, the mentioned ratios may show an earlier approach to perturbative QCD than the individual cross sections. We have performed the first complete separation of the four unpolarized electromagnetic structure functions above the dominant resonances in forward, exclusive π(±) electroproduction on the deuteron at central Q(2) values of 0.6, 1.0, 1.6  GeV(2) at W=1.95  GeV, and Q(2)=2.45  GeV(2) at W=2.22  GeV. Here, we present the L and T cross sections, with emphasis on RL and RT, and compare them with theoretical calculations. Results for the separated ratio RL indicate dominance of the pion-pole diagram at low -t, while results for RT are consistent with a transition between pion knockout and quark knockout mechanisms.

Enhanced Incretin Effects of Exendin-4 Expressing Chimeric Plasmid Based On Two-Step Transcription Amplification System with Dendritic Bioreducible Polymer for the Treatment of Type 2 Diabetes

Glucagon-like peptide 1 (GLP-1) agonist, exenxdin-4, is currently being advanced as a promising diabetes remedy via a variety of incretin actions similar with GLP-1. In this study, we investigated an effective anti-diabetic therapy via exendin-4 expressing chimeric plasmid based on two-step transcription amplification (TSTA) system with dendrimer-type bioreducible polymer for more improved incretin-based gene therapy. Arginine-grafted poly (cystaminebisacrylamide-diaminohexane) (ABP)-conjugated poly (amido amine) (PAMAM) dendrimer (PAM-ABP) was used as gene carrier. PAM-ABP/chimeric DNA polyplex was markedly elevated exendin-4 expression in ectopic cells as well as increased insulin production through an enhanced activation of protein kinase K (PKA) induced by up-regulation of exendin-4-stimulated cyclic adenosine monophosphate (cAMP) in pancreatic β-cell. Consistent with these results, intravenous administration of PAM-ABP/chimeric DNA polyplex improved glucoregulotory effects, as well as increased insulin secretion by high expression of exendin-4 in blood in type 2 diabetic mice with no any toxicity. Our exendin-4 system can be attributed to provide a potential diabetes therapeutic agent for improved incretin gene therapy.

Germline single nucleotide polymorphisms associated with response of urothelial carcinoma to platinum-based therapy: the role of the host

BACKGROUND

Variations in urothelial carcinoma (UC) response to platinum chemotherapy are common and frequently attributed to genetic and epigenetic variations of somatic DNA. We hypothesized that variations in germline DNA may contribute to UC chemosensitivity.

PATIENTS AND METHODS

DNA from 210 UC patients treated with platinum-based chemotherapy was genotyped for 80 single nucleotide polymorphisms (SNPs). Logistic regression was used to examine the association between SNPs and response, and a multivariable predictive model was created. Significant SNPs were combined to form a SNP score predicting response. Eleven UC cell lines were genotyped as validation.

RESULTS

Six SNPs were significantly associated with 101 complete or partial responses (48%). Four SNPs retained independence association and were incorporated into a response prediction model. Each additional risk allele was associated with a nearly 50% decrease in odds of response [odds ratio (OR) = 0.51, 95% confidence interval 0.39-0.65, P = 1.05 × 10(-7)). The bootstrap-adjusted area under the curves of this model was greater than clinical prognostic factors alone (0.78 versus 0.64). The SNP score showed a positive trend with chemosensitivity in cell lines (P = 0.115).

CONCLUSIONS

Genetic variants associated with response of UC to platinum-based therapy were identified in germline DNA. A model using these genetic variants may predict response to chemotherapy better than clinical factors alone.

Paclitaxel-conjugated PEG and arginine-grafted bioreducible poly (disulfide amine) micelles for co-delivery of drug and gene

We developed a paclitaxel-conjugated polymeric micelle, ABP-PEG3.5k-Paclitaxel (APP) consisting of poly (ethylene glycol) (PEG) and arginine-grafted poly (cystaminebisacrylamide-diaminohexane) (ABP) for the co-delivery of gene and drug. The APP polymer self-assembled into cationic polymeric micelles with a critical micelle concentration (CMC) value of approximately 0.062 mg/mL, which was determined from measurements of the UV absorption of pyrene. The micelles have an average size of about 3 nm and a zeta potential of about +14 mV. Due to the positive surface charge, APP micelles formed polyplexes with plasmid DNA approximately 200 nm in diameter. The luciferase gene and mouse interleukin-12 (IL-12) gene was used to monitor gene delivery potency. APP polyplexes showed increased gene delivery efficiency and cellular uptake with higher anticancer potency than paclitaxel alone. These results demonstrate that an APP micelle-based delivery system is well suitable for the co-delivery of gene and drug.

Delivery of two-step transcription amplification exendin-4 plasmid system with arginine-grafted bioreducible polymer in type 2 diabetes animal model

Exendin-4, glucagon-like peptide 1 (GLP-1) receptor agonist, is an exocrine hormone, which has potent insulinotropic actions similar to GLP-1 such as stimulating insulin biosynthesis, facilitating glucose concentration dependent insulin secretion, slowing gastric emptying, reducing food intake and stimulating β-cell proliferation. Exendin-4, also, has a longer half-life than GLP-1, due to its resistance to degradation by dipeptidyl peptidase-IV (DPP-IV). In spite of its many advantages as a therapeutic agent for diabetes, its clinical application is still restricted. Thus, to improve the activity of exendin-4 in vivo, gene therapy system was developed as an alternative method. An exendin-4 expression system was constructed using the two-step transcription amplification (TSTA) system, which is composed of pβ-Gal4-p65 and pUAS-SP-exendin-4 with combining the advantages of signal peptide (SP) in order to facilitate its secretion in ectopic cells or tissue. Arginine-grafted cyctaminebisacrylamide-diaminohexane polymer (ABP) was used as a gene carrier. Increased expression of exendin-4, glucose dependent insulin secretion in NIT-1 insulinoma cells, and high insulin expression in the presence of DPP-IV were evaluated in vitro after delivery of ABP/TSTA-SP-exendin-4. Blood glucose levels in diabetic mice were decreased dramatically from the third day for experimental period after single intravenous administration with ABP/TSTA-SP-exendin-4. The highest insulinotropic effect of exendin-4 was also observed in the ABP/TSTA/SP-exendin-4-treated mice groups, compared with the others groups from the 3rd day after injection. TSTA exendin-4 expression system with SP and ABP polymer has a potential gene therapy for the treatment of type 2 diabetes.

Polymer-based delivery of glucagon-like Peptide-1 for the treatment of diabetes

The incretin hormones, glucagon-like peptide-1 (GLP-1) and its receptor agonist (exendin-4), are well known for glucose homeostasis, insulinotropic effect, and effects on weight loss and food intake. However, due to the rapid degradation of GLP-1 by dipeptidylpeptidase-IV (DPP-IV) enzyme and renal elimination of exendin-4, their clinical applications have been restricted. Although exendin-4 has longer half-life than GLP-1, it still requires frequent injections to maintain efficacy for the treatment of diabetes. In recent decades, various polymeric delivery systems have been developed for the delivery of GLP-1 and exendin-4 genes or peptides for their long-term action and the extra production in ectopic tissues. Herein, we discuss the modification of the expression cassettes and peptides for long-term production and secretion of the native peptides. In addition, the characteristics of nonviral or viral system used for a delivery of a modified GLP-1 or exendin-4 are described. Furthermore, recent efforts to improve the biological half-life of GLP-1 or exendin-4 peptide via chemical conjugation with various smart polymers via chemical conjugation compared with native peptide are discussed.

Linearized oncolytic adenoviral plasmid DNA delivered by bioreducible polymers

As an effort to overcome limits of adenovirus (Ad) as a systemic delivery vector for cancer therapy, we developed a novel system using oncolytic Ad plasmid DNA with two bioreducible polymers: arginine-grafted bioreducible poly(disulfide amine)polymer (ABP) and PEG5k-conjugated ABP (ABP5k) in expectation of oncolytic effect caused by progeny viral production followed by replication. The linearized Ad DNAs for active viral replication polyplexed with each polymer were able to replicate only in human cancer cells and produce progeny viruses. The non-immunogenic polymers delivering the DNAs markedly elicited to evade the innate and adaptive immune response. The biodistribution ratio of the polyplexes administered systemically was approximately 99% decreased in liver when compared with naked Ad. Moreover, tumor-to-liver ratio of the Ad DNA delivered by ABP or ABP5k was significantly elevated at 229- or 419-fold greater than that of naked Ad, respectively. The ABP5k improved the chance of the DNA to localize within tumor versus liver with 1.8-fold increased ratio. In conclusion, the innovative and simple system for delivering oncolytic Ad plasmid DNA with the bioreducible polymers, skipping time-consuming steps such as generation and characterization of oncolytic Ad vectors, can be utilized as an alternative approach for cancer therapy.

Enhancing the therapeutic efficacy of adenovirus in combination with biomaterials

With the reason that systemically administered adenovirus (Ad) is rapidly extinguished by innate/adaptive immune responses and accumulation in liver, in vivo application of the Ad vector is strictly restricted. For achieving to develop successful Ad vector systems for cancer therapy, the chemical or physical modification of Ad vectors with polymers has been generally used as a promising strategy to overcome the obstacles. With polyethylene glycol (PEG) first in order, a variety of polymers have been developed to shield the surface of therapeutic Ad vectors and well accomplished to extend circulation time in blood and reduce liver toxicity. However, although polymer-coated Ads can successfully evacuate from a series of guarding systems in vivo and locate within tumors by enhanced permeability and retention (EPR) effect, the possibility to entering into the target cell is few and far between. To endow targeting moiety to polymer-coated Ad vectors, a diversity of ligands such as tumor-homing peptides, growth factors or antibodies, have been introduced with avoiding unwanted transduction and enhancing therapeutic efficacy. Here, we will describe and classify the characteristics of the published polymers with respect to Ad vectors. Furthermore, we will also compare the properties of variable targeting ligands, which are being utilized for addressing polymer-coated Ad vectors actively.

Active targeting of RGD-conjugated bioreducible polymer for delivery of oncolytic adenovirus expressing shRNA against IL-8 mRNA

Even though oncolytic adenovirus (Ad) has been highlighted in the field of cancer gene therapy, transductional targeting and immune privilege still remain difficult challenges. The recent reports have noted the increasing tendency of adenoviral surface shielding with polymer to overcome the limits of its practical application. We previously reported the potential of the biodegradable polymer, poly(CBA-DAH) (CD) as a promising candidate for efficient gene delivery. To endow the selective-targeting moiety of tumor vasculature to CD, cRGDfC well-known as a ligand for cell-surface integrins on tumor endothelium was conjugated to CD using hetero-bifunctional cross-linker SM (PEG)(n). The cytopathic effects of oncolytic Ad coated with the polymers were much more enhanced dose-dependently when compared with that of naked Ad in cancer cells selectively. Above all, the most potent oncolytic effect was assessed with the treatment of Ad/CD-PEG(500)-RGD in all cancer cells. The enhanced cytopathic effect of Ad/RGD-conjugated polymer was specifically inhibited by blocking antibodies to integrins, but not by blocking antibody to CAR. HT1080 cells treated with Ad/CD-PEG(500)-RGD showed strong induction of apoptosis and suppression of IL-8 and VEGF expression as well. These results suggest that RGD-conjugated bioreducible polymer might be used to deliver oncolytic Ad safely and efficiently for tumor therapy.

A hypoxia- and {alpha}-fetoprotein-dependent oncolytic adenovirus exhibits specific killing of hepatocellular carcinomas

PURPOSE

Oncolytic adenoviruses (Ad) constitute a new promising modality of cancer gene therapy that displays improved efficacy over nonreplicating Ads. We have previously shown that an E1B 19-kDa-deleted oncolytic Ad exhibits a strong cell-killing effect but lacks tumor selectivity. To achieve hepatoma-restricted cytotoxicity and enhance replication of Ad within the context of tumor microenvironment, we used a modified human α-fetoprotein (hAFP) promoter to control the replication of Ad with a hypoxia response element (HRE).

EXPERIMENTAL DESIGN

We constructed Ad-HRE(6)/hAFPΔ19 and Ad-HRE(12)/hAFPΔ19 that incorporated either 6 or 12 copies of HRE upstream of promoter. The promoter activity and specificity to hepatoma were examined by luciferase assay and fluorescence-activated cell sorting analysis. In addition, the AFP expression- and hypoxia-dependent in vitro cytotoxicity of Ad-HRE(6)/hAFPΔ19 and Ad-HRE(12)/hAFPΔ19 was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and cytopathic effect assay. In vivo tumoricidal activity on subcutaneous and liver orthotopic model was monitored by noninvasive molecular imaging.

RESULTS

Ad-HRE(12)/hAFPΔ19 exhibited enhanced tumor selectivity and cell-killing activity when compared with Ad-hAFPΔ19. The tumoricidal activity of Ad-HRE(12)/hAFPΔ19 resulted in significant inhibition of tumor growth in both subcutaneous and orthotopic models. Histologic examination of the primary tumor after treatment confirmed accumulation of viral particles near hypoxic areas. Furthermore, Ad-HRE(12)/hAFPΔ19 did not cause severe inflammatory immune response and toxicity after systemic injection.

CONCLUSIONS

The results presented here show the advantages of incorporating HREs into a hAFP promoter-driven oncolytic virus. This system is unique in that it acts in both a tissue-specific and tumor environment-selective manner. The greatly enhanced selectivity and tumoricidal activity of Ad-HRE(12)/hAFPΔ19 make it a promising therapeutic agent in the treatment of liver cancers.

Active targeting and safety profile of PEG-modified adenovirus conjugated with herceptin

PEGylation of adenovirus (Ad) increases plasma retention and reduces immunogenicity, but decreases the accessibility of virus particles to target cells. We tested whether PEGylated Ad conjugated to Herceptin (Ad-PEG-HER) can be used to treat Her2/neu-positive cells in vitro and in vivo to demonstrate the therapeutic feasibility of this Ad formulation. Ad-PEG-HER transduced Her2/neu-overexpressing cancer cells through a specific interaction between Herceptin and Her2/neu. Ad-PEG-HER treatment resulted in higher plasma retention and lower neutralizing antibody and IL-6 production than naked Ad. This formulation was extended to generate a Her2/neu-targeted, PEGylated oncolytic Ad (DWP418-PEG-HER). DWP418-PEG-HER specifically killed Her2/neu-positive cells and performed better than non-targeted and naked Ad in vivo. DWP418-PEG-HER showed a 10(10)-fold increase in the liver to tumor biodistribution compared with naked Ad. Immunohistochemical staining confirmed accumulation of Ad E1A in tumors. These data suggest that targeted gene therapy with the PEGylated Ad conjugated with Herceptin might shed a light on its therapeutic application for metastatic cancer in the future.

Primary cardiomyocyte-targeted bioreducible polymer for efficient gene delivery to the myocardium

A cardiomyocyte-targeted Fas siRNA delivery system was developed using primary cardiomyocyte (PCM) specific peptide-modified polymers with high transfection efficiency and low cytotoxicity. Primary cardiomyocyte (PCM) specific peptide, selected by phage display, was conjugated to bioreducible poly(cystamine bisacrylamide-diaminohexane, CBA-DAH) (PCD). The specificity of the PCM-modified polymer to cardiomyocytes was confirmed by competition study with free PCM ligand and by delivery to non-cardiomyocyte NIH 3T3 fibroblasts. The cellular binding and uptake of the PCM-polymer/pDNA polyplex was inhibited by addition of free PCM peptide. The impact of PCM conjugation on cellular uptake and transfection efficiency was greater in H9C2 rat cardiomyocytes than in NIH 3T3 cells. Fas siRNA/PCM-polymer polyplexes exhibited significant Fas gene silencing in rat cardiomyocytes under hypoxic conditions, leading to inhibition of cardiomyocyte apoptosis. These findings demonstrate the utility of the addition of a primary cardiomyocyte (PCM) specific peptide modification to a bioreducible polymer for targeted delivery of Fas siRNA to inhibit cardiomyocyte apoptosis.

The effect of surface modification of adenovirus with an arginine-grafted bioreducible polymer on transduction efficiency and immunogenicity in cancer gene therapy

Adenoviral vectors offer many advantages for cancer gene therapy, including high transduction efficiency, but safety concerns related to severe immunogenicity and other side effects have led to careful reconsideration of their use in human clinical trials. To overcome these issues, a strategy of generating hybrid vectors that combine viral and non-viral elements as more intelligent gene carriers has been employed. Here, we coated adenovirus (Ad) with an arginine-grafted bioreducible polymer (ABP) via electrostatic interaction. We examined the effect of ABP-coated Ad complex at various ABP molecules/Ad particle ratios. Enhanced transduction efficiency was observed in cells treated with cationic ABP polymer-coated Ad complex compared to naked Ad. We also examined the coating of Ad with ABP polymers at the optimal polymer ratio using dynamic light scattering and transmission electron microscopy. In both high and low coxsackie virus and adenovirus receptor (CAR)-expressing cells, ABP-coated Ad complex produced higher levels of transgene expression than cationic polymer 25K PEI. Notably, high cytotoxicity was observed with 25K PEI-coated Ad complex treatment, but not with ABP-coated Ad complex treatment. In addition, ABP-coated Ad complex was not significantly inhibited by serum, in contrast to naked Ad. Moreover, ABP-coated Ad complex significantly reduced the innate immune response relative to naked Ad, as assessed by interleukin-6 (IL-6) cytokine release from macrophage cells. Overall, our studies demonstrate that Ad complex formed with ABP cationic polymer may improve the efficiency of Ad and be a promising tool for cancer gene therapy.

Proto-oncogene FBI-1 represses transcription of p21CIP1 by inhibition of transcription activation by p53 and Sp1

Aberrant transcriptional repression through chromatin remodeling and histone deacetylation has been postulated as the driving force for tumorigenesis. FBI-1 (formerly called Pokemon) is a member of the POK family of transcriptional repressors. Recently, FBI-1 was characterized as a critical oncogenic factor that specifically represses transcription of the tumor suppressor gene ARF, potentially leading indirectly to p53 inactivation. Our investigations on transcriptional repression of the p53 pathway revealed that FBI-1 represses transcription of ARF, Hdm2 (human analogue of mouse double minute oncogene), and p21CIP1 (hereafter indicated as p21) but not of p53. FBI-1 showed a more potent repressive effect on p21 than on p53. Our data suggested that FBI-1 is a master controller of the ARF-Hdm2-p53-p21 pathway, ultimately impinging on cell cycle arrest factor p21, by inhibiting upstream regulators at the transcriptional and protein levels. FBI-1 acted as a competitive transcriptional repressor of p53 and Sp1 and was shown to bind the proximal Sp1-3 GC-box and the distal p53-responsive elements of p21. Repression involved direct binding competition of FBI-1 with Sp1 and p53. FBI-1 also interacted with corepressors, such as mSin3A, NCoR, and SMRT, thereby deacetylating Ac-H3 and Ac-H4 histones at the promoter. FBI-1 caused cellular transformation, promoted cell cycle proliferation, and significantly increased the number of cells in S phase. FBI-1 is aberrantly overexpressed in many human solid tumors, particularly in adenocarcinomas and squamous carcinomas. The role of FBI-1 as a master controller of the p53 pathway therefore makes it an attractive therapeutic target.

A cyclic RGD-coated peptide nanoribbon as a selective intracellular nanocarrier

We have synthesized a peptide-based supramolecular building block consisting of a cyclic Arg-Gly-Asp (cRGD) peptide segment and a beta-sheet-forming peptide segment. The block peptide was shown to self-assemble into a cRGD-coated nanoribbon structure, as revealed by circular dichroism (CD), dynamic light scattering (DLS), and transmission electron microscopy (TEM) studies. We have shown that this cRGD-coated nanoribbon can encapsulate hydrophobic guest molecules and deliver them into cells. Colocalization of the nanoribbon with LysoTracker and the selective intracellular delivery results suggests that the cRGD-coated nanoribbon is likely to be internalized into the cells through integrin receptors.

E1A- and E1B-Double mutant replicating adenovirus elicits enhanced oncolytic and antitumor effects

Gene-modified replication-competent adenoviruses (Ads) are emerging as a promising new modality for the treatment of cancer. We have previously shown that E1B 19kDa and E1B 55kDa gene-deleted Ad (Ad-DeltaE1B19/55) exhibits improved tumor-specific replication and cell lysis, leading to an enhanced antitumor effect. In an effort to increase cancer cell selectivity of a replicating adenovirus, we first generated 11 E1A mutant Ads (Ad-E1mt1 to Ad-E1mt11) with deletion or substitution in retinoblastoma (pRb)-binding sites of E1A. Of these, Ad-E1mt7 demonstrated significant improvement in cytopathic effect (CPE) and viral replication in a cancer cell-specific manner. To further enhance the cancer cell specificity of Ad-E1mt7, Ad-DeltaE1Bmt7 was generated, in which both the E1B 19kDa and E1B 55kDa genes were deleted. As assessed in CPE assay and immunoblot analysis for Ad fiber expression, Ad-DeltaE1Bmt7 exerted marked enhancement in cancer cell-specific killing as well as viral replication in comparison with its comparative controls (Ad-E1mt7, Ad-DeltaE1B55). Furthermore, the growth of established human cervical carcinoma in nude mice was significantly suppressed by intratumoral injection of Ad-DeltaE1Bmt7. In summary, we have developed an oncolytic adenovirus with a significantly improved therapeutic profile for cancer treatment.

Retargeting of adenoviral gene delivery via Herceptin–PEG–adenovirus conjugates to breast cancer cells

Targeted adenoviral gene delivery using human epidermal growth factor receptor 2 (HER2/neu) is one of the promising strategies for enhancing the transduction efficacy of PEGylated adenovirus (PEG-ADV). The viral capsid of adenovirus carrying the green fluorescent protein (GFP) was conjugated with bifunctional polyethylene glycol (PEG). The surface of PEG-ADV was then further conjugated with anti-HER2/neu monoclonal antibody (MAb), Herceptin (Trastuzumab; HER) to grant HER2/neu over-expressed breast cancer cells specific targeting. The PEG-ADV and Herceptin immobilized PEG-ADV (HER-PEG-ADV) extents of retargeting were evaluated, as compared to those of naked ADV. In summary, HER-PEG-ADV exhibited more enhanced level of GFP expression than PEG-ADV did for MDA-MB-435 and MDA-MB-468 cells (a HER2/neu positive cell line), but not for a HER2/neu deficient U251N cells. PEGylated ADV significantly reduced innate immune response likewise, as judged from the amount of interleukin 6 released from macrophage cells. Consequently, this study suggests that HER-PEG-ADV conjugates enable ADV to become more potential therapeutic tools through overcoming the limitation of ADV against immune system and non-specificity.

Ameroid rings for gradual chronic constriction of the sciatic nerve in rats: contribution of different nerves to neuropathic pain

Mononeuropathy was induced by placing an ameroid ring around the sciatic nerve and was compared with chronic constriction injury (CCI) of the sciatic nerve [Pain 33 (1988) 87] in rats. Mechanical allodynia was assessed and the role of sciatic and saphenous afferents (Adelta and C) in thermal hyperalgesia investigated. A shorter duration of mechanical allodynia in ameroid rats as compared to CCI rats was observed. Thermal hyperalgesia was observed in the saphenous innervated skin of the hindpaw for Adelta and C nociceptors in ameroid and for Adelta nociceptors only in CCI rats, respectively. The sciatic innervated skin showed a thermal hypoalgesia with a fast onset for Adelta afferents and a slower onset for C afferents in CCI and ameroid rats. The duration of both thermal hypo- and hyperalgesia was longer in ameroid rats. We conclude that ameroid rings are a useful tool for the investigation of long-duration hyperalgesic effects of nerve injury, as the effects were more stable and seen for a longer time (>8 weeks) as compared to the CCI model. The uninjured saphenous afferents, in particular C fibers, mediate thermal hyperalgesia after chronic constriction of the sciatic nerve using an ameroid ring.

Risk factors for failure of 5-fluorouracil needling revision for failed conjunctival filtration blebs

PURPOSE

To investigate the risk factors for failure of 5-fluorouracil (5-FU) needling revision, a useful procedure for restoring a failed filtration bleb.

DESIGN

Interventional case series.

METHODS

Retrospectively conducted study.

SETTING

Institutional.

STUDY POPULATION

Sixty-four eyes of 64 consecutive glaucoma patients that underwent 5-FU needling revisions for failed filtering bleb following either trabeculectomy or phaco-trabeculectomy with or without adjunctive mitomycin C (MMC).

OBSERVATION PROCEDURES

Goldmann applanation tonometry, Kaplan-Meier survival analysis, and Cox proportional hazards regression analysis.

MAIN OUTCOME MEASURES

Successful outcome of the initial 5-FU needling revision, arbitrarily defined as target intraocular pressure (IOP) control with not more than two topical glaucoma medications and no additional 5-FU needling or other surgical procedures, was analyzed by Kaplan-Meier survival analysis, and risk factors for failure of the initial 5-FU needling revision were analyzed by Cox proportional hazards regression analysis.

RESULTS

The cumulative success rate of the initial 5-FU needling revision was 45% at 1 year, 33% at 2 years, and 28% at 4 years. Failure of the initial 5-FU revision correlated significantly with preneedling IOP > 30 mm Hg (P =.0003), lack of MMC use during the previous filtration surgery (P =.013), and IOP >10 mm Hg immediately following needling revision (P =.0012) according to Cox's proportional hazards regression analysis.

CONCLUSIONS

Pre-needling IOP > 30 mm Hg, lack of MMC use during the previous filtration surgery, and IOP > 10 mm Hg immediately after needling were found to be significant risk factors for failure of the initial 5-FU needling procedure. Therefore, it is important to monitor IOP closely following needling revision in those patients with such risk factors. They are more likely to require additional therapeutic interventions, including repeat needling revisions.

Capillary gel electrophoresis with sinusoidal voltammetric detection: a strategy to allow four-"color" DNA sequencing

A novel detection strategy for DNA sequencing applications that utilizes a frequency-based electrochemical method is reported. Sinusoidal voltammetry is used to selectively identify four unique redox molecules that are covalently attached to the 5'-end of a 20-base sequencing primer. The tags used in this work are ferrocene derivatives with different substituents attached to the ferrocene ring, where the electron-donating or -withdrawing character of the substituent alters the half-wave potential of the modified ferrocene. Therefore, each tag has a unique SV frequency spectrum that can be easily identified in the frequency domain. In this work, the discrimination of one tag versus all others is accomplished through a "phase-nulling" technique. The signal for each tag is selectively eliminated while the other three responses remain virtually unchanged. This analysis scheme allows for the selective identification of each tagged oligonucleotide eluting in sieving polymer capillary gel electrophoresis with a separation efficiency of 2 x 10(6) theoretical plates per meter. This separation efficiency is sufficient to perform "low-resolution" DNA sequencing; the conditions used in this work have not yet been optimized for high-resolution sequencing applications.

Roles of Ets proteins, NF-kappa B and nocodazole in regulating induction of transcription of mouse germline Ig alpha RNA by transforming growth factor-beta 1

Antibody class switch recombination (CSR) occurs after antigen activation of B cells. CSR is directed to specific heavy chain isotypes by cytokines and B cell activators that induce transcription from the unrearranged, or germline (GL), C(H) region genes. Transforming growth factor (TGF)-beta1 is essential for switch recombination to IgA due to its ability to induce transcription from GL Ig alpha genes. It has been shown that the promoters which regulate transcription of mouse and human GL alpha RNAs contain a TGF-beta1-responsive element that binds Smad and core binding factor (CBFalpha)/AML/PEBPalpha/RUNX: They also contain other elements which bind the transcription factors CREB, BSAP and Ets family proteins. In this manuscript we demonstrate that two tandem Ets sites in the mouse GL alpha promoter bind the transcription factors Elf-1 and PU.1, and that the 3' site is essential for expression of a luciferase reporter gene driven by the GL alpha promoter. Binding of Elf-1 to the GL alpha promoter is inducible by lipopolysaccharide in nuclear extracts from splenic B cells. An NF-kappaB site is identified, although it does not contribute to expression of the promoter in reporter gene assays. Since CSR to IgA is greatly reduced in NF-kappaB/p50-deficient mice, these data support the hypothesis that NF-kappaB has roles in switching in addition to regulation of GL transcription. Finally, we demonstrate that nocodazole, which disrupts microtubules that sequester Smad proteins in the cytoplasm, stimulates transcription from the GL alpha promoter.