Transgene-mediated expression of tumor necrosis factor soluble receptor attenuates morphine tolerance in rats

Opiate/narcotic analgesics are the most effective treatments for chronic severe pain, but their clinical utility is often hampered by the development of analgesic tolerance. Recent evidence suggests chronic morphine may activate glial cells to release proinflammatory cytokines. In this study, we used herpes simplex virus (HSV) vectors-based gene transfer to dorsal root ganglion to produce a local release of p55 TNF soluble receptor in the spinal cord in rats with morphine tolerance. Subcutaneous inoculation of HSV vectors expressing p55 TNF soluble receptor into the plantar surface of the hindpaws, enhanced the antinociceptive effect of acute morphine in rats. Subcutaneous inoculation of those vectors into hindpaws also delayed the development of chronic morphine tolerance in rats. TNF soluble receptor expressed by HSV vector reduced gene transcription of mRNA of spinal TNFα and IL-1β induced by repeated morphine. Furthermore, we found that TNF soluble receptor mediated by HSV, reversed the upregulation of TNFα, IL-1β and phosphorylation of p38 mitogen-activated protein kinase (MAPK) induced by repeated morphine. These results support the concept that proinflammatory cytokines may play an important role in the pathogenesis induced by morphine. This study provides a novel approach to treating morphine tolerance.

Mithramycin reduces expression of fibro-proliferative mRNAs in human gingival fibroblasts

Fibrosis is characterized by loss of normal structure and function of a tissue or organ resulting from excessive fibroblast proliferation and extracellular matrix production. Currently, there is no efficient treatment for fibrosis. Herein, we test effects of the drug mithramycin, which targets the Sp1 family of transcription factors, on mRNA expression by human gingival fibroblasts. Mithramycin reduced expression of connective tissue growth factor and type I collagen mRNAs. Microarray profiling revealed that mithramycin selectively blocked expression of cell proliferation and transforming growth factor-beta (TGF-β) signalling clusters. These microarray data were validated using real-time polymerase chain reaction and western blot analyses. Mithramycin suppressed expression of key profibrotic TGF-β signalling mediators, Smad3 and p300, as well as cell proliferation. Taken together, these data suggest that the Sp1 family of transcription factors may contribute to expression of fibrogenic genes in human gingival fibroblasts; drugs targeting the Sp1 family may be beneficial in treatment of fibro-proliferative diseases.

IKKα represses a network of inflammation and proliferation pathways and elevates c-Myc antagonists and differentiation in a dose-dependent manner in the skin

Inhibitor of nuclear factor κB kinase-α (IKKα) is required for maintaining skin homeostasis and preventing skin tumorigenesis. However, its signaling has not been extensively investigated. In the present study, we generated two mouse lines that expressed different levels of transgenic IKKα in the basal epidermis under the control of keratin-5 promoter and further evaluated their effects on the major pathways of inflammation, proliferation, and differentiation in the skin. Regardless of the transgenic IKKα levels, the mice develop normally. Because IKKα deletion in keratinocytes blocks terminal differentiation and induces epidermal hyperplasia and skin inflammation, we depleted the endogenous IKKα in these transgenic mice and found that the transgenic IKKα represses epidermal thickness and induces terminal differentiation in a dose-dependent manner. Also, transgenic IKKα was found to elevate expression of Max dimer protein 1 (Mad1) and ovo-like 1, c-Myc antagonists, but repress activities of epidermal growth factor receptor (EGFR), extracellular signal-regulated kinase (ERK), Jun-amino-terminal kinases, c-Jun, signal transducer and activator of transcription 3 (Stat3), and growth factor levels in a dose-dependent fashion in the skin. Moreover, EGFR reduction represses IKKα deletion-induced excessive ERK, Stat3 and c-Jun activities, and skin inflammation. These new findings indicate that elevated IKKα expression not only represses epidermal thickness and induces terminal differentiation, but also suppresses skin inflammation by an integrated loop. Thus, IKKα maintains skin homeostasis through a broad range of signaling pathways.

Dual-color fluorescence cross-correlation spectroscopy on a planar optofluidic chip

Fluorescence cross-correlation spectroscopy (FCCS) is a highly sensitive fluorescence technique with distinct advantages in many bioanalytical applications involving interaction and binding of multiple components. Due to the use of multiple beams, bulk optical FCCS setups require delicate and complex alignment procedures. We demonstrate the first implementation of dual-color FCCS on a planar, integrated optofluidic chip based on liquid-core waveguides that can guide liquid and light simultaneously. In this configuration, the excitation beams are delivered in predefined locations and automatically aligned within the excitation waveguides. We implement two canonical applications of FCCS in the optofluidic lab-on-chip environment: particle colocalization and binding/dissociation dynamics. Colocalization is demonstrated in the detection and discrimination of single-color and double-color fluorescently labeled nanobeads. FCCS in combination with fluorescence resonance energy transfer (FRET) is used to detect the denaturation process of double-stranded DNA at nanomolar concentration.

Abstract 4109: A 5-gene signature (sig) predicts clinical benefit from erlotinib in non-small cell lung cancer (NSCLC) patients (pts) harboring wild-type (wt) EGFR & KRAS

Background: Despite a low response rate, erlotinib (E) improves survival in a subset of NSCLC pts with wt EGFR but there are no established markers for identifying pts likely to have clinical benefit. We hypothesized that a gene expression sig could be used for this purpose. Material and Methods: We used pretreatment gene expression profiles (Affymetrix HG1.0ST) from 101 chemo-refractory pts in our Biomarkers-Integrated Approaches of Targeted Therapy for Lung Cancer Elimination (BATTLE) treated with E, E+bexarotene (EB), sorafenib (S), or vandetanib (V). 24 cases of wt EGFR & KRAS tumors treated with E or EB were compared to train the signature (two-sided t-test), using the primary end-point of the trial [8-week disease control (8wDC)]. Principal component (PC) analysis and a logistic regression model were used to develop the sig. Gene expression profiles from 108 NSCLC cell lines (Illumina), with available E IC50 (N=94) and DNA methylation profiling (N=66, Illumina), were used for in vitro studies. Results: 113 genes were differentially expressed between pts with or without 8wDC (false discovery rate 30%; P=0.004). Leave-one-out cross validation with various gene list lengths produced a 5-gene sig, including lipocalin 2 (LCN2), with a specificity, sensitivity and accuracy of 80% to predict 8wDC. In pts treated with E or EB, using the median sig score, the 8wDC rate in the sig-positive group was 83% compared with 0% in the sig-negative group; the sig did not predict 8wDC in pts treated with S or V (Mantel-Haenszel chi-squared test P=0.023). The improvement in 8wDC in the sig-positive group translated to an increased progression-free survival (PFS) (hazard ratio=0.12, 95% confidence interval: 0.03-0.46, P=0.001; log-rank P=0.0004; median PFS: 12.5 weeks vs. 7.2 weeks). We tested the sig in an independent set of 47 wt EGFR&KRAS cell lines. It predicted E sensitivity with an area under the curve of 78% (P=0.002). The first PC of the sig and the IC50 for E were correlated (r=−0.47, P=0.0009). In 108 NSCLC cell lines, LCN2 gene expression was bimodal and correlated with the IC50 for E (r=−0.46, P=0.001). Degree of methylation and expression level of LCN2 were inversely in wt EGFR & KRAS NSCLC cells (r=−0.79, P<0.0001, N=33). Cell lines with completely unmethylated LCN2 were more sensitive to E compared to those with LCN2 full methylation (N=36) (P=0.006); the difference remained significant in wt EGFR & KRAS cell lines (P=0.014). Conclusion: We identified a 5-gene sig predictive of PFS benefit in NSCLC pts with wt EGFR & KRAS treated with E, but not S or V The sig was also predictive of E sensitivity in vitro. LCN2 was the strongest individual marker of sensitivity and may be epigenetically regulated.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4109. doi:10.1158/1538-7445.AM2011-4109

Results from a low-energy analysis of the CDMS II germanium data

We report results from a reanalysis of data from the Cryogenic Dark Matter Search (CDMS II) experiment at the Soudan Underground Laboratory. Data taken between October 2006 and September 2008 using eight germanium detectors are reanalyzed with a lowered, 2 keV recoil-energy threshold, to give increased sensitivity to interactions from weakly interacting massive particles (WIMPs) with masses below ∼10  GeV/c(2). This analysis provides stronger constraints than previous CDMS II results for WIMP masses below 9  GeV/c(2) and excludes parameter space associated with possible low-mass WIMP signals from the DAMA/LIBRA and CoGeNT experiments.

A Bayesian response-adaptive covariate-balanced randomization design with application to a leukemia clinical trial

We propose a Bayesian response-adaptive covariate-balanced (RC) randomization design for multiple-arm comparative clinical trials. The goal of the design is to skew the allocation probability to more efficacious treatment arms, while also balancing the distribution of the covariates across the arms. In particular, we first propose a new covariate-adaptive randomization (CA) method based on a prognostic score that naturally accommodates continuous and categorical prognostic factors and automatically assigns imbalance weights to covariates according to their importance in response prediction. We then incorporate this CA design into a group sequential response-adaptive randomization (RA) scheme. The resulting RC randomization design combines the advantages of both CA and RA randomizations and meets the design goal. We illustrate the proposed design through its application to a phase II leukemia clinical trial, and evaluate its operating characteristics through simulation studies.

Conditional β1-integrin-deficient mice display impaired pancreatic β cell function

β1-Integrin, a critical regulator of β cell survival and function, has been shown to protect against cell death and promote insulin expression and secretion in rat and human islet cells in vitro. The aim of the present study was to examine whether the knockout of β1-integrin in collagen I-producing cells would have physiological and functional implications in pancreatic endocrine cells in vivo. Using adult mice with a conditional knockout of β1-integrin in collagen I-producing cells, the effects of β1-integrin deficiency on glucose metabolism and pancreatic endocrine cells were examined. Male β1-integrin-deficient mice display impaired glucose tolerance, with a significant reduction in pancreatic insulin content (p < 0.01). Morphometric analysis revealed a significant reduction in β cell mass (p < 0.001) in β1-integrin-deficient mice, along with a significant decrease in β cell proliferation, Pdx-1 and Nkx6.1 expression when compared with controls. Interestingly, these physiological and morphometric alterations in female β1-integrin-deficient mice were less significant. Furthermore, β1-integrin-deficient mice displayed decreased FAK (p < 0.05) and ERK1/2 (p < 0.001) phosphorylation, reduced cyclin D1 levels (p < 0.001) and increased caspase 3 cleavage (p < 0.01), while no changes in Akt phosphorylation were observed, indicating that the β1-integrin signals through the FAK-MAPK-ERK pathway in vivo. Our results demonstrate that β1-integrin is involved in the regulation of glucose metabolism and contributes to the maintenance of β cell survival and function in vivo.

Prostate cancer outcomes and polymorphism in LHRH and LH receptors and SHBG

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Background: The hypothalamic-pituitary-gonadal axis is integral to androgen synthesis and the management of prostate cancer (PC). Genetic variation in the receptors of this pathway may impact the efficiency of signal transduction and overall clinical course. We examined polymorphisms in four receptors central to this pathway: luteinizing hormone-releasing hormone receptor (LHRHR), luteinizing hormone receptor (LHR), androgen receptor (AR) and steroid hormone binding globulin (SHBG). We examined the association between these genotypes and survival.

Methods: Patients diagnosed with PC between 1999 and 2004 in Los Angeles County were identified using the Los Angeles County Cancer Registry as part of the California Collaborative Prostate Cancer study, a multiethnic, population based case-control study. Included in this analysis were 1232 men with PC: 631 with advanced stage PC at diagnosis and 430 with high-grade PC. The ethnic breakdown was 376 African-American, 355 Hispanic and 501 Caucasian. DNA was extracted from blood and genotypes for LHR, LHRHR, AR and SHBG were assayed using TaqMan or GeneScan methods. Vital status and cause of death was obtained by linking to the Cancer Registry records. Hazard ratios were estimated by fitting Cox proportional hazards models.

Results: As of September 2010, 396 (32%) had died and 122 (10%) had died of PC. In the multivariate model, there was a significant association between disease specific survival and genetic variation in LHRHR, LHR and SHBG. Hazard ratios (HR) for carriers (vs. non-carriers) of the LHR312 minor allele were 1.63 (95% CI: 1.08-2.45) among all cases and 2.04 (1.23-3.39) for high- grade cases. The LHRHR16 minor allele was rare among African Americans; the HR among Caucasians was 1.90 (1.15-3.13) and did not vary by disease grade. The SHGB356 minor allele was associated with survival only among high-grade cases with a HR of 2.38 (1.18-4.81). In addition, when comparing cases to controls, the LHR312 minor allele was inversely associated with PC incidence.

Conclusions: Genetic variation in the LHRHR, LHR and SHGB genes are associated with PC survival and warrant further analysis to define their role as prognostic and predictive markers.

No significant financial relationships to disclose.

Hollow waveguides with low intrinsic photoluminescence fabricated with Ta(2)O(5) and SiO(2) films

A type of integrated hollow core waveguide with low intrinsic photoluminescence fabricated with Ta(2)O(5) and SiO(2) films is demonstrated. Hollow core waveguides made with a combination of plasma-enhanced chemical vapor deposition SiO(2) and sputtered Ta(2)O(5) provide a nearly optimal structure for optofluidic biofluorescence measurements with low optical loss, high fabrication yield, and low background photoluminescence. Compared to earlier structures made using Si(3)N(4), the photoluminescence background of Ta(2)O(5) based hollow core waveguides is decreased by a factor of 10 and the signal-to-noise ratio for fluorescent nanobead detection is improved by a factor of 12.

High dose human insulin and insulin glargine promote T24 bladder cancer cell proliferation via PI3K-independent activation of Akt

BACKGROUND

This study was to investigate the effects of human insulin and insulin glargine on proliferation of T24 human bladder cancer cells and the implication of the PI3K/Akt and MEK/ERK1/2 pathways.

METHODS

After exposure to insulin or glargine at the indicated concentrations for certain time courses, in the absence or presence of inhibitor for MEK (PD98059) or PI3K (LY294002), T24 cell proliferation was evaluated by CCK-8 assay. Phosphorylation of Akt and ERK1/2 was analyzed by Western blot.

RESULTS

Insulin and glargine similarly induced phosphorylation of Akt and slight increases in T24 cell proliferation at 10-100IU/L. LY294002 remarkably reduced T24 cell proliferation in all groups. However, in the presence of LY294002, cell growth was still promoted by insulin and glargine relative to LY294002-treated group. Accordingly, LY294002 profoundly reduced protein levels of pAkt, while insulin and glargine increased pAkt in T24 cells pretreated with LY294002 as compared with cells treated with LY294002 alone. PD98059 reduced pERK while enhanced T24 cell proliferation. Insulin and glargine increased pERK at 15, 30, 60 min, not at 24h.

CONCLUSIONS

High dose human insulin and insulin glargine similarly promoted T24 bladder cancer cell proliferation via PI3K-independent activation of Akt.