GDF15 is an epithelial-derived biomarker of idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is the most common and devastating of the interstitial lung diseases. Epithelial dysfunction is thought to play a prominent role in disease pathology, and we sought to characterize secreted signals that may contribute to disease pathology. Transcriptional profiling of senescent type II alveolar epithelial cells from mice with epithelial-specific telomere dysfunction identified the transforming growth factor-ß family member, growth and differentiation factor 15 (Gdf15), as the most significantly upregulated secreted protein. Gdf15 expression is induced in response to telomere dysfunction and bleomycin challenge in mice. Gdf15 mRNA is expressed by lung epithelial cells, and protein can be detected in peripheral blood and bronchoalveolar lavage following bleomycin challenge in mice. In patients with IPF, GDF15 mRNA expression in lung tissue is significantly increased and correlates with pulmonary function. Single-cell RNA sequencing of human lungs identifies epithelial cells as the primary source of GDF15, and circulating concentrations of GDF15 are markedly elevated and correlate with disease severity and survival in multiple independent cohorts. Our findings suggest that GDF15 is an epithelial-derived secreted protein that may be a useful biomarker of epithelial stress and identifies IPF patients with poor outcomes.

Loss of Twist1 in the Mesenchymal Compartment Promotes Increased Fibrosis in Experimental Lung Injury by Enhanced Expression of CXCL12.

Idiopathic pulmonary fibrosis (IPF) is a disease characterized by the accumulation of apoptosis-resistant fibroblasts in the lung. We have previously shown that high expression of the transcription factor Twist1 may explain this prosurvival phenotype in vitro. However, this observation has never been tested in vivo. We found that loss of Twist1 in COL1A2+ cells led to increased fibrosis characterized by very significant accumulation of T cells and bone marrow-derived matrix-producing cells. We found that Twist1-null cells expressed high levels of the T cell chemoattractant CXCL12. In vitro, we found that the loss of Twist1 in IPF lung fibroblasts increased expression of CXCL12 downstream of increased expression of the noncanonical NF-κB transcription factor RelB. Finally, blockade of CXCL12 with AMD3100 attenuated the exaggerated fibrosis observed in Twist1-null mice. Transcriptomic analysis of 134 IPF patients revealed that low expression of Twist1 was characterized by enrichment of T cell pathways. In conclusion, loss of Twist1 in collagen-producing cells led to increased bleomycin-induced pulmonary fibrosis, which is mediated by increased expression of CXCL12. Twist1 expression is associated with dysregulation of T cells in IPF patients. Twist1 may shape the IPF phenotype and regulate inflammation in fibrotic lung injury.

Variable Susceptibility to Cigarette Smoke-Induced Emphysema in 34 Inbred Strains of Mice Implicates Abi3bp in Emphysema Susceptibility.

Chronic obstructive pulmonary disease (COPD) is caused by a complex interaction of environmental exposures, most commonly cigarette smoke, and genetic factors. Chronic cigarette smoke exposure in the mouse is a commonly used animal model of COPD. We aimed to expand our knowledge about the variable susceptibility of inbred strains to this model and test for genetic variants associated with this trait. To that end, we sought to measure differential susceptibility to cigarette smoke-induced emphysema in the mouse, identify genetic loci associated with this quantitative trait, and find homologous human genes associated with COPD. Alveolar chord length (CL) in 34 inbred strains of mice was measured after 6 months of exposure to cigarette smoke. After testing for association, we connected a murine candidate locus to a published meta-analysis of moderate-to-severe COPD. We identified deleterious mutations in a candidate gene in silico and measured gene expression in extreme strains. A/J was the most susceptible strain in our survey (Δ CL 7.0 ± 2.2 µm) and CBA/J was the least susceptible (Δ CL -0.3 ± 1.2 µm). By integrating mouse and human genome-wide scans, we identified the candidate gene Abi3bp. CBA/J mice harbor predicted deleterious variants in Abi3bp, and expression of the gene differs significantly between CBA/J and A/J mice. This is the first report of susceptibility to cigarette smoke-induced emphysema in 34 inbred strains of mice, and Abi3bp is identified as a potential contributor to this phenotype.

Expression of RXFP1 Is Decreased in Idiopathic Pulmonary Fibrosis. Implications for Relaxin-based Therapies.

RATIONALE: Relaxin is a hormone that has been considered as a potential therapy for patients with fibrotic diseases. OBJECTIVES: To gauge the potential efficacy of relaxin-based therapies in idiopathic pulmonary fibrosis (IPF), we studied gene expression for relaxin/insulin-like family peptide receptor 1 (RXFP1) in IPF lungs and controls. METHODS: We analyzed gene expression data obtained from the Lung Tissue Research Consortium and correlated RXFP1 gene expression data with cross-sectional clinical and demographic data. We also employed ex vivo donor and IPF lung fibroblasts to test RXFP1 expression in vitro. We tested CGEN25009, a relaxin-like peptide, in lung fibroblasts and in bleomycin injury. MEASUREMENTS AND MAIN RESULTS: We found that RXFP1 is significantly decreased in IPF. In patients with IPF, the magnitude of RXFP1 gene expression correlated directly with diffusing capacity of the lung for carbon monoxide (P < 0.0001). Significantly less RXFP1 was detected in vitro in IPF fibroblasts than in donor controls. Transforming growth factor-ß decreased RXFP1 in both donor and IPF lung fibroblasts. CGEN25009 was effective at decreasing bleomycin-induced, acid-soluble collagen deposition in vivo. The relaxin-like actions of CGEN25009 were abrogated by RXFP1 silencing in vitro, and, in comparison with donor lung fibroblasts, IPF lung fibroblasts exhibited decreased sensitivity to the relaxin-like effects of CGEN25009. CONCLUSIONS: IPF is characterized by the loss of RXFP1 expression. RXFP1 expression is directly associated with pulmonary function in patients with IPF. The relaxin-like effects of CGEN25009 in vitro are dependent on expression of RXFP1. Our data suggest that patients with IPF with the highest RXFP1 expression would be predicted to be most sensitive to relaxin-based therapies.

AP2 suppresses osteoblast differentiation and mineralization through down-regulation of Frizzled-1.

Transcription factor activating protein 2 (AP2) plays an important role in cellular differentiation. Although profound craniofacial and long bone developmental abnormalities have been observed in AP2-knockout mice, the molecular effects of AP2 on osteoblasts are poorly defined. We demonstrated that AP2 regulates the expression of human Frizzled 1 (FZD1), a co-receptor for the Wnt signalling pathway, in human osteoblast cell lines and primary bone marrow stromal cells (BMSCs). We also identified a putative AP2-binding site in the FZD1 proximal promoter in silico and characterized this binding element further in Saos2 in vitro by ChIP, electrophoretic mobility shift and promoter reporter assays. The transcriptional repression of the FZD1 promoter by AP2 was confirmed in normal human fetal osteoblasts (hFOB). Furthermore, overexpression of AP2 resulted in a significant reduction in both differentiation and mineralization of Saos2 cells. Knockdown of FZD1 expression before AP2 up-regulation diminished the AP2-dependent inhibition of Saos2 cell differentiation and mineralization. Similarly, overexpressing FZD1 before AP2 treatment in both Saos2 and BMSCs diminished the inhibitory effect of AP2 on osteoblast differentiation and mineralization. Taken together, these results demonstrate that AP2 is a negative regulator of osteoblast differentiation and mineralization, and its inhibitory effect may be mediated in part through down-regulation of FZD1 expression.

MicroRNA-590 promotes cervical cancer cell growth and invasion by targeting CHL1.

MicroRNAs (miRNAs) may function as oncogenes or tumor suppressors. Here, we identified that miR-590-5p was up-regulated in human cervical cancer. Over-expression of miR-590-5p promoted cervical cancer cell growth, cell cycle and invasion via Growth curve, Colony formation, FACS and Transwell assays in HeLa and C33A cell lines. Subsequently, CHL1 was identified as a potential miR-590-5p target by bioinformatics analysis. Moreover, we showed that CHL1 was negatively regulated by miR-590-5p at the posttranscriptional level, via a specific target site within the 3'UTR by luciferase reporter assay. Furthermore, the mRNA and protein levels of CHL1 in cervical cancer cells were downregulated by miR-590-5p. And we identified the cell phenotype altered by miR-590-5p can be rescued by over-expression of CHL1. Therefore, our findings suggest that miR-590-5p acts as an oncogene by targeting the CHL1 gene and promotes cervical cancer proliferation. The findings of this study contribute to current understanding of the functions of miR-590-5p in cervical cancer.

[Effects of verapamil on the proliferation and migration of cervical cancer cells].

OBJECTIVE: To investigate the effects of Verapamil, a L-type calcium channel blocker, on the proliferation and migration of human cervical cancer cells. METHODS: Human cervical cancer cell lines (HeLa cells) were incubated with serum-free media for 24 hours. These cells were then treated with Verapamil for different time points. Cell proliferation was evaluated by MTT assay and EdU fluorescent assay. The migration of cells was measured by the wound healing assay. Results MTT assay demonstrated that, Verapamil (1, 5, 10 and 20 microg/mL concentrations) could inhibit the proliferation of HeLa cells after 48 or 72 hours treatment. The inhibition rate for 48 h-treatment was 20.87% +/- 1.71%, 23.55% +/- 4.46%, 28.65% +/- 1.32%, 27.37% +/- 3.05% respectively (P < 0.05). After 5, 10 and 20 microg/mL concentrations of verapamil treatment for 24h, the proportion of HeLa cells in the stage of DNA synthesis was 15.7% +/- 1.2%, 11.7% +/- 0.3%, 2.8% +/- 0.5% as evaluated with EdU fluorescent assay, which was significantly lower than that of control (27.34% +/- 2.1%, P < 0.05). With the increase of drug concentrations, Verapamil could significantly suppressed the DNA synthesis in HeLa cell. Cell migration assay revealed that, treatment with Verapamil (5, 10 and 20 microg/mL) for 24 hours significantly inhibited cells migration distance (P < 0.05). CONCLUSION: Calcium channel blocker Verapamil could inhibit proliferation and migration of the cervical cancer HeLa cells.

Pyrrolidine dithiocarbamate (PDTC) blocks apoptosis and promotes ionizing radiation-induced necrosis of freshly-isolated normal mouse spleen cells.

Ionizing radiation (IR) is a pro-oxidant that kills cells by both apoptotic and necrotic mechanisms. Pyrrolidine dithiocarbamate (PDTC) is a thiol-containing compound that may act either as a pro- or anti-oxidant depending on the experimental conditions. This study was designed to determine whether PDTC would reduce or enhance IR-induced cell death of freshly-isolated normal mouse B6/129 spleen cells (NMSC). We determined the effect of increasing doses of IR, PDTC alone and PDTC followed by IR on the viability of NMSC. Annexin V and propidium iodide (Annexin V/PI) staining demonstrated a dose and time-dependent relationship in which PDTC enhanced the percentage of IR-induced apoptotic/necrotic NMSC. Trypan blue dye inclusion confirmed that a loss of membrane integrity was occurring 1 h after incubation with PDTC plus IR. Reduction in the glutathione (GSH)/glutathione disulfide (GSSG) ratio and GSH demonstrated that both IR (8.5 Gy) and PDTC acted as pro-oxidants, but their mechanisms of action differed: In contrast to IR, which promoted p53 activation and caspase 3/7-mediated apoptosis, PDTC inhibited IR-induced p53 and caspase 3/7 activity. However, PDTC increased H(2)O(2) formation and necrosis, resulting in an overall increase in IR-induced cell death. Catalase prevented the PDTC-induced increase in IR cytotoxicity implicating the generation of H(2)O(2) as a major factor in this mechanism. These results demonstrate that in NMSC PDTC acts as pro-oxidant and enhances IR-induced cell cytotoxicity by increasing H(2)O(2)formation and thiol oxidation. As such, they strongly suggest that the use of PDTC as an adjunct to reduce radiation toxicity should be avoided.

[Relationship between polymorphism of hypoxia inducible factor-1alpha and cervical cancer in Han population in Sichuan Province of China].

OBJECTIVE: To investigate the relationship between single nucleotide polymorphism (SNP) of hypoxia inducible factor-1alpha (HIF-1alpha) C1772T and genetic susceptibility to and clinical-pathological features of cervical cancers in Han population in Sichuan province of China. METHODS: A case control study was undertaken in Sichuan province of China, with 97 patients with uterine cervical cancer as case group and 117 negative for intraepithelial lesion or malignancy (NILM) patients as control group. Their gene types in HIF-1alpha C1772T were identified with a combination of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: The distribution of the frequencies of T/T, T/C and C/C genotypes in the two groups differed significantly (P < 0.01); T allele frequency in the patients with cervical cancer was much higher than that in the controls (P < 0.01). There were no significant differences in the distributions of T/T, T/C and C/C genotypes among cervical cancer patients at different FIGO stages, pathological grading, stromal invasive depth, lymph node metastasis and vascular invasions (P > 0.05). CONCLUSION: T/C and T/T genotypes of HIF-1alpha C1772T are genetic susceptibility factors for cervical cancer in Han population in Sichuan province of China. HIF-1alpha C1772T SNP probably has no relationship with clinical-pathological features of cervical cancer.

[Influences of human beta-defensin 1 on the replication and expression of HPV18 in Hela cell].

OBJECTIVE: Investigate the influences of human beta-defensinl (hbetaD1) on the replication and expression of HPV18 in Hela cell. METHODS: Gene transfection: mediated by Fugen HD, hbetaD1/psectag plasmid was transfected to Hela cell [hbetaD1/psectag : liposome complexes (hbetaD1/psectag : lip)group], and control groups [psectag : liposome complexes(psectag : lip) group and blank group) were also established. After transfection, the expression of the target gene in Hela cell was investigated by the method of immunocytochemistry. 48 h and 72 h after the transfection, the change of the copy number of HPV18 DNA in Hela cell was investigated respectively by the quantitative fluorescent PCR method, and the change of the HPV18 E6 mRNA in Hela cell was evaluated by the semiquantitative RT-PCR. RESULTS: 48 h and 72 h after the transfection of hbetaD1/psectag plasmid to Hela cell, hbetaD1 was expressed in both of the two groups, and the latter showed a tendency of stronger expression. Compared with the control groups, the copy number of HPV18 DNA in Hela cell in the hbetaD1/psectag : lip group increased at 48 h and decreased at 72 h after the transfection, but the change was not statistically significant. 48 h after the transfection, compared with the control groups, the expression of HPV18 E6 mRNA in Hela cell in the hbetaD1/psectag : lip group changed a little; and 72 h after the transfection, the expression level of HPV18 E6 mRNA decreased significantly (P < 0.05). CONCLUSION: hbetaD1 displayed an inhibitory effect to the expression of HPV18 mRNA in Hela cell in a concentration-dependent pattern, but no significant effect on the duplication of HPV18 DNA.

Hepatic insulin sensitivity is improved in high-fat diet-fed Park2 knockout mice in association with increased hepatic AMPK activation and reduced steatosis.

Park2 is an E3 ubiquitin ligase known for its role in mitochondrial quality control via the mitophagy pathway. Park2 KO mice are protected from diet-induced obesity and hepatic insulin sensitivity is improved in high-fat diet (HFD)-fed Park2 KO mice even under body weight-matched conditions. In order to better understand the cellular mechanism by which Park2 KO mice are protected from diet-induced hepatic insulin resistance, we determined changes in multiple pathways commonly associated with the pathogenesis of insulin resistance, namely levels of bioactive lipid species, activation of the endoplasmic reticulum (ER) stress response and changes in cytokine levels and signaling. We report for the first time that whole-body insulin sensitivity is unchanged in regular chow (RC)-fed Park2 KO mice, and that liver diacylglycerol levels are reduced and very-long-chain ceramides are increased in Park2 KO mice fed HFD for 1 week. Hepatic transcriptional markers of the ER stress response were reduced and plasma tumor necrosis factor-α (TNFα), interleukin-6 and -10 (IL6, IL10) were significantly increased in HFD-fed Park2 KO mice; however, there were no detectable differences in hepatic inflammatory signaling pathways between groups. Interestingly, hepatic adenylate charge was reduced in HFD-fed Park2 KO liver and was associated increased activation of AMPK. These data suggest that negative energy balance that contributed to protection from obesity during chronic HFD manifested at the level of the hepatocyte during short-term HFD feeding and contributed to the improved hepatic insulin sensitivity.

Petite Integration Factor 1 (PIF1) helicase deficiency increases weight gain in Western diet-fed female mice without increased inflammatory markers or decreased glucose clearance.

Petite Integration Factor 1 (PIF1) is a multifunctional helicase present in nuclei and mitochondria. PIF1 knock out (KO) mice exhibit accelerated weight gain and decreased wheel running on a normal chow diet. In the current study, we investigated whether Pif1 ablation alters whole body metabolism in response to weight gain. PIF1 KO and wild type (WT) C57BL/6J mice were fed a Western diet (WD) rich in fat and carbohydrates before evaluation of their metabolic phenotype. Compared with weight gain-resistant WT female mice, WD-fed PIF1 KO females, but not males, showed accelerated adipose deposition, decreased locomotor activity, and reduced whole-body energy expenditure without increased dietary intake. Surprisingly, PIF1 KO females did not show obesity-induced alterations in fasting blood glucose and glucose clearance. WD-fed PIF1 KO females developed mild hepatic steatosis and associated changes in liver gene expression that were absent in weight-matched, WD-fed female controls, linking hepatic steatosis to Pif1 ablation rather than increased body weight. WD-fed PIF1 KO females also showed decreased expression of inflammation-associated genes in adipose tissue. Collectively, these data separated weight gain from inflammation and impaired glucose homeostasis. They also support a role for Pif1 in weight gain resistance and liver metabolic dysregulation during nutrient stress.

[An exploration of the expression of MK and MVD in cervical cancer tissues before and after NACT].

OBJECTIVE: To investigate the clinical effect of neoadjuvant chemotherapy (NACT) and its influence on the expressions of MK and MVD in cervical cancer cells. METHODS: The expressions of MK, CD34 were determined by immunohistochemistry in 35 cases of cervical cancer before and after NACT. RESULTS: Among the 35 cases treated with NACT, 4 (11.43%) were complete remission (CR), 25 (71.43%) partial remission (PR). The total effective rate of NACT (CR+PR) was 82.86%. The expressions of MK and MVD decreased dramatically after NACT. In cases who reacted positively to NACT, the expression of MK and the level of MVD decreased significantly after the treatment (P<0.05). While in cases who reacted poorly to NACT no such changes were observed in the expression of MK (P>0.05); but the level of MVD also decreased in those cases. CONCLUSION: NACT is an effective treatment for cervical cancer. The expressions of MK and MVD decreased after NACT treatment. It implied that one of the mechanisms of NACT may be the suppression of angiogenesis, and the expression of MK may serve as an indicator for predicting the therapeutic effect of NACT.

Association of genetic variation in COMT gene with pain related to sickle cell disease in patients from the walk-PHaSST study.

BACKGROUND: Vaso-occlusive pain episodes (VOEs) are the hallmark of sickle cell disease (SCD), and our current understanding of disease biology, treatment, and psychological covariates does not adequately explain the variability of pain in SCD. Functional variants in catechol-O-methyltransferase (COMT) gene contribute to variability in pain perception, but their impact on pain perception in African American SCD patients is not well known. METHODS: We studied COMT single-nucleotide polymorphisms (SNPs) rs6269, rs4633, rs4818, rs4680, and rs165599 to determine their relationship to patient self-reported pain, the number of acute VOEs, and their impact on daily life and health care utilization in 438 hemoglobin SS patients who participated in the walk-PHaSST study. RESULTS: In women, two risk SNPs (rs4633 and rs165599) and the corresponding haplotype (ATCAA) were associated with increased frequency of pain-related emergency room visit. CONCLUSION: COMT functional variants may predispose SCD patients to worse acute pain in women. The association of COMT variants with the intensity of self-reported acute pain warrants further genetic study of pain perception in SCD.

[Relationship between the expression of fragile histidine (FHIT) and the development of vulvar carcinoma].

OBJECTIVE: To explore the relationship between the reduction of FHIT expression of fragile histidine (FHIT) and the development of vulvar carcinoma. METHODS: The expression of the FHIT product was detected by immunochemistry in the tissue samples of 20 normal vulvas, 22 vulvar intraepithelial neoplasias (VINs), and 60 primary vulvar carcinomas. RESULTS: The expressive rates of FHIT protein in the squamous epithelium of normal vulvas, VIN I - II, VIN II, and noninvasive and invasive vulvar carcinoma were 100% (20/20), 72.7% (8/11), 45.5% (5/11), and 21.7% (13/60) respectively (P<0.05). The expressive rates of FHIT protein in the well differentiated, intermediately differentiated and poorly differentiated invasive vulav carcinoma were 60.0% (9/15), 20.0% (3/15), and 3.3% (1/30) respectively (P<0.05). The expressive rate of the impaired FHIT protein in the invasive vulva carcinoma with lymphnode metastasis (10%) was lower than that without lymphnode metastasis (27.5%). CONCLUSION: Abnormal FHIT expression may play an important role in the progression of vulvar carcinoma. The expression of FHIT may provide important information for the prognosis of vulva carcinoma.

Transcriptional Regulation of Frizzled-1 in Human Osteoblasts by Sp1.

The wingless pathway has a powerful influence on bone metabolism and is a therapeutic target in skeletal disorders. Wingless signaling is mediated in part through the Frizzled (FZD) receptor family. FZD transcriptional regulation is poorly understood. Herein we tested the hypothesis that Sp1 plays an important role in the transcriptional regulation of FZD1 expression in osteoblasts and osteoblast mineralization. To test this hypothesis, we conducted FZD1 promoter assays in Saos2 cells with and without Sp1 overexpression. We found that Sp1 significantly up-regulates FZD1 promoter activity in Saos2 cells. Chromatin immunoprecipitation (ChIP) and electrophoretic mobility shift (EMSA) assays identified a novel and functional Sp1 binding site at -44 to -40 from the translation start site in the FZD1 promoter. The Sp1-dependent activation of the FZD1 promoter was abolished by mithramycin A (MMA), an antibiotic affecting both Sp1 binding and Sp1 protein levels in Saos2 cells. Similarly, down-regulation of Sp1 in hFOB cells resulted in less FZD1 expression and lower alkaline phosphatase activity. Moreover, over-expression of Sp1 increased FZD1 expression and Saos2 cell mineralization while MMA decreased Sp1 and FZD1 expression and Saos2 cell mineralization. Knockdown of FZD1 prior to Sp1 overexpression partially abolished Sp1 stimulation of osteoblast differentiation markers. Taken together, our results suggest that Sp1 plays a role in human osteoblast differentiation and mineralization, which is at least partially mediated by Sp1-dependent transactivation of FZD1.

Elevated NT-pro-brain natriuretic peptide level is independently associated with all-cause mortality in HIV-infected women in the early and recent HAART eras in the Women's Interagency HIV Study cohort.

BACKGROUND: HIV-infected individuals are at increased risk of right and left heart dysfunction. N-terminal-pro-brain natriuretic peptide (NT-proBNP), a marker of cardiac ventricular strain and systolic dysfunction, may be associated with all-cause mortality in HIV-infected women. The aim of this study was to determine if elevated levels of NT-proBNP is associated with increased mortality in HIV-infected women. DESIGN: Prospective cohort study. METHODS AND RESULTS: We measured NT-proBNP in 936 HIV-infected and 387 age-matched HIV-uninfected women early (10/11/94 to 7/17/97) and 1082 HIV-infected and 448 HIV-uninfected women late (4/1/08 to 10/7/08) in the highly active antiretroviral therapy (HAART) periods in the Women's Interagency HIV Study. An NT-proBNP >75th percentile was more likely in HIV-infected persons, but only statistically significant in the late period (27% vs. 21%, unadjusted p = 0.03). In HIV-infected participants, NT-proBNP>75th percentile was independently associated with worse 5-year survival in the early HAART period (HR 1.8, 95% CI 1.3-2.4, p<0.001) and remained a predictor of mortality in the late HAART period (HR 2.8, 95% CI 1.4-5.5, p = 0.002) independent of other established risk covariates (age, race/ethnicity, body mass index, smoking, hepatitis C serostatus, hypertension, renal function, and hemoglobin). NT-proBNP level was not associated with mortality in HIV-uninfected women. CONCLUSION: NT-proBNP is a novel independent marker of mortality in HIV-infected women both when HAART was first introduced and currently. As NT-proBNP is often associated with both pulmonary hypertension and left ventricular dysfunction, these findings suggest that these conditions may contribute significantly to adverse outcomes in this population, requiring further definition of causes and treatments of elevated NT-proBNP in HIV-infected women.

Alternative farnesoid structures induce different conformational outcomes upon the Drosophila ortholog of the retinoid X receptor, ultraspiracle.

In view of recent studies that the ligand-binding pocket of the Drosophila melanogaster nuclear hormone receptor, ultraspiracle (dUSP), is a necessary component of dUSP-dependent transcriptional activation by methyl epoxyfarnesoate, we have assessed qualitative differences in the effect of farnesoid and dodecanoid compounds on receptor conformation and transcriptional activation. Farnesoids possessing terminal alcohol, aldehyde, acid, ester and/or epoxide moieties induced different changes in the local environment of the ligand-binding pocket, as monitored by the change each induced in the fluorescence of the two tryptophan residues existing in dUSP (that are situated 10 residues apart on the alpha-helix 5 that forms one lining of ligand-binding pocket). Similarly, each compound differed in the extent that it promoted an increase in anisotropy (dimerization state) of the receptor. Dodecanoid derivatives were much weaker in causing such effects. Methyl expoxyfarnesoate (insect juvenile hormone III) exhibited the greatest biological activity to increase transcription of a DR12JHECore reporter construct in transfected Sf9 cells, even though it did not exert the most suppression of USP fluorescence nor exert the greatest increase in USP anisotropy. In a comparison of farnesoid derivatives possessing the three side branches either as all methyl groups (JH III), or one of the side branches as ethyl (JH II), or two of the side branches as ethyl (JH I), the JH III and JH I were more similar to each other in the fluorescence suppression and in vivo morphogenetic activity than either was to JH II, evidencing that dUSP does not sense JH II as a structural 'intermediate' between JH III and JH I. Ligand-binding domains of vertebrate retinoid X receptors respond to agonists by repositioning alpha-helix 12 to the edge of a hydrophobic groove, and there with the groove jointly forms a coactivator binding surface. When alpha-helix 12 in dUSP was mutated to place two signaling tryptophan residues its C-terminus, fluorescence signaling indicated that upon dUSP binding of methyl epoxyfarnesoate, the alpha-helix 12 was repositioned differently than what occurred upon binding of non-JH farnesoids. These leads on alternative ligand-induced conformations that dUSP can adopt provide a foundation for commercial development of synthetic molecules that induce specific dUSP conformations, and for identification of in vivo conditions under which endogenous molecules may exert these conformational outcomes to this receptor.

Diagnostic value of 18F-FDG-PET or PET-CT in recurrent cervical cancer: a systematic review and meta-analysis.

OBJECTIVES: Accurate detection of recurrent cervical cancer remains a clinical difficulty. This study aims to assess the diagnostic value of PET or PET-computed tomography (PET-CT) using F-fluorodeoxyglucose (F-FDG) in recurrent cervical cancer using a meta-analysis. STUDY DESIGN: All published studies in English evaluating the diagnostic value of PET or PET-CT in detecting recurrent cervical cancer were collected. The methodological quality of the included studies was evaluated. Pooled sensitivity, specificity, diagnostic odds ratio, and summary receiver-operating characteristic curves were obtained using statistical software. Twenty studies were included in the meta-analysis. RESULTS: The meta-analysis showed that the pooled sensitivity and specificity of PET and PET-CT to detect distant metastasis in recurrent cervical cancer were 0.87 [95% confidence interval (CI): 0.80-0.92] and 0.97 (95% CI: 0.96-0.98), respectively. The pooled sensitivity and specificity for local regional recurrence were 0.82 (95% CI: 0.72-0.90) and 0.98 (95% CI: 0.96-0.99), respectively. CONCLUSION: F-FDG-PET and PET-CT are valuable methods for the assessment of recurrent cervical cancer.