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Thousands of resting state functional magnetic resonance imaging (RS-fMRI) articles have been published on brain disorders. For precise localization of abnormal brain activity, a voxel-level comparison is needed. Because of the large number of voxels in the brain, multiple comparison correction (MCC) must be performed to reduce false positive rates, and a smaller P value (usually including either liberal or stringent MCC) is widely recommended. The study suggests that a stringent MCC may reduce the number of false positive results and that the brain regions surviving MCC are true positive results and thus can improve the reproducibility between studies. However, determining the clusters that represent true positives is difficult because ground truths have not been established for many brain disorders that do not present visible structural abnormalities, e.g., Parkinson's disease (PD) and many psychiatric disorders. Meta-analysis provides robust results that can be used to investigate reproducibility across studies. However, most existing neuroimaging meta-analytic articles are based on only a few peak coordinates reported in the original articles, namely coordinate-based meta-analysis (CB-meta). The current REST-meta-PD study included raw RS-fMRI data from 15 cohorts of PD patients and performed a meta-analysis of the amplitude of low frequency fluctuations (ALFF). We used the robustness results of the meta-analysis to test whether liberal or stringent MCC could increase reproducibility and reduce false positive rates.

Objective CareHPV is a human papillomavirus (HPV) DNA test for low-resource settings (LRS). This study assesses optimum triage strategies for careHPV-positive women in LRS. Methods A total of 2,530 Chinese women were concurrently screened for cervical cancer with visual inspection with acetic acid (VIA), liquid-based cytology and HPV testing by physician- and self-collected careHPV, and physician-collected Hybrid Capture 2 (HC2). Screen-positive women were referred to colposcopy with biopsy and endocervical curettage as necessary. HPV-positivity was defined as ≥1.0 relative light units/cutoff (RLU/CO) for both careHPV and HC2. Primary physician-HC2, physician-careHPV and self-careHPV and in sequential screening with cytology, VIA, or increased HPV test-positivity performance, stratified by age, were assessed for cervical intraepithelial neoplasia (CIN) grade 2/3 or worse (CIN2/3+) detection. Results The sensitivities and specificities of primary HPV testing for CIN2+ were: 83.8%, 88.1% for physician-careHPV; 72.1%, 88.2% for self-careHPV; and 97.1%, 86.0% for HC2. Physician-careHPV test-positive women with VIA triage had a sensitivity of 30.9% for CIN2+ versus 80.9% with cytology triage. Self-careHPV test-positive women with VIA triage was 26.5% versus 66.2% with cytology triage. The sensitivity of HC2 test-positive women with VIA triage was 38.2% versus 92.6% with cytology triage. The sensitivity of physician-careHPV testing for CIN2+ decreased from 83.8% at ≥1.0 RLU/CO to 72.1% at ≥10.00 RLU/CO, while the sensitivity of self-careHPV testing decreased from 72.1% at ≥1.0 RLU/CO to 32.4% at ≥10.00 RLU/CO; similar trends were seen with age-stratification. Conclusions VIA and cytology triage improved specificity for CIN2/3 than no triage. Sensitivity with VIA triage was unsuitable for a mass-screening program. VIA provider training might improve this strategy. Cytology triage could be feasible where a high-quality cytology program exists. Triage of HPV test-positive women by increased test positivity cutoff adds another LRS triage option.

Thousands of papers using resting-state functional magnetic resonance imaging (RS-fMRI) have been published on brain disorders. Results in each paper may have survived correction for multiple comparison. However, since there have been no robust results from large scale meta-analysis, we do not know how many of published results are truly positives. The present meta-analytic work included 60 original studies, with 57 studies (4 datasets, 2266 participants) that used a between-group design and 3 studies (1 dataset, 107 participants) that employed a within-group design. To evaluate the effect size of brain disorders, a very large neuroimaging dataset ranging from neurological to psychiatric isorders together with healthy individuals have been analyzed. Parkinson’s disease off levodopa (PD-off) included 687 participants from 15 studies. PD on levodopa (PD-on) included 261 participants from 9 studies. Autism spectrum disorder (ASD) included 958 participants from 27 studies. The meta-analyses of a metric named amplitude of low frequency fluctuation (ALFF) showed that the effect size (Hedges’ g) was 0.19 - 0.39 for the 4 datasets using between-group design and 0.46 for the dataset using within-group design. The effect size of PD-off, PD-on and ASD were 0.23, 0.39, and 0.19, respectively. Using the meta-analysis results as the robust results, the between-group design results of each study showed high false negative rates (median 99%), high false discovery rates (median 86%), and low accuracy (median 1%), regardless of whether stringent or liberal multiple comparison correction was used. The findings were similar for 4 RS-fMRI metrics including ALFF, regional homogeneity, and degree centrality, as well as for another widely used RS-fMRI metric namely seed-based functional connectivity. These observations suggest that multiple comparison correction does not control for false discoveries across multiple studies when the effect sizes are relatively small. Meta-analysis on un-thresholded t-maps is critical for the recovery of ground truth. We recommend that to achieve high reproducibility through meta-analysis, the neuroimaging research field should share raw data or, at minimum, provide un-thresholded statistical images.

International collaborative training programs for graduate students are widespread, but studies on their educational impact are limited. As an advanced cancer institute in China, Cancer Hospital Chinese Academy of Medical Science (CHCAMS) attaches great importance to international exchanges and cooperation within graduate education. The Department of Epidemiology of CHCAMS has been involved in several existing international training programs and has also launched a short-term training program in cooperation with foreign universities and institutes from 2008. Fogarty International Clinical Research Scholars and Fellows (FICRS-F) Program and the Fulbright-Fogarty Fellowship Program are the most typical examples of our practice in international cooperation on graduate education over these years. Our department has gained substantial experience in graduate-level international collaborative training, focused on cancer epidemiology. This paper is a brief introduction to the practice of different programs in our department and students’ achievements during and after training. Moreover, we attempt to serve as a reference and help promote the training of graduate students pursuing careers in cancer research or global health by other universities or research institutes.

Phage PhiC31 integrase-mediated gene delivery is believed to be safer than using retroviral vectors since the protein confines its insertion of the target gene to a limited number of sites in mammalian genomes. To evaluate its safety in human cells, it is important to understand the interactions between this integrase and cellular proteins. Here we show that PhiC31 integrase interacts with TTRAP as presented by yeast two-hybrid and co-immunoprecipitation assays. Reducing the expression of endogenous TTRAP can increase the efficiency of PhiC31 integrase-mediated integration. A possible effect of interaction between PhiC31 integrase and TTRAP was highlighted by the fact that PhiC31 integrase inhibited the NFkappaB activation mediated by IL-1 in a dose-dependent manner. Because low dose of PhiC31 integrase can mediate considerable recombination events, we suggest that low dose of PhiC31 integrase be used when this integrase is applied in human cells.

TTRAP is a multi-functional protein that is involved in multiple aspects of cellular functions including cell proliferation, apoptosis and the repair of DNA damage. Here, we demonstrated that the lentivirus-mediated overexpression of TTRAP significantly inhibited cell growth and induced apoptosis in osteosarcoma cells. The ectopic TTRAP suppressed the growth and colony formation capacity of two osteosarcoma cell lines, U2OS and Saos-2. Cell apoptosis was induced in U2OS cells and the cell cycle was arrested at G2/M phase in Saos-2 cells. Exogenous expression of TTRAP in serum-starved U2OS and Saos-2 cells induced an increase in caspase-3/-7 activity and a decrease in cyclin B1 expression. In comparison with wild-type TTRAP, mutations in the 5'-tyrosyl-DNA phosphodiesterase activity of TTRAP, in particular TTRAPE152A, showed decreased inhibitory activity on cell growth. These results may aid in clarifying the physiological functions of TTRAP, especially its roles in the regulation of cell growth and tumorigenesis. [BMB Reports 2013; 46(2): 113-118]

Cdc20 is a co-activator of the anaphase-promoting complex/cyclosome (APC/C complex), which recruits substrates at particular phases of the cell cycle and mediates their degradation. Sp100 is a PML-NB scaffold protein, which localizes to nuclear particles during interphase and disperses from them during mitosis, participates in viral resistance, transcriptional regulation, and apoptosis. However, its metabolism during the cell cycle has not yet been fully characterized. We found a putative D-box in Sp100 using the Eukaryotic Linear Motif (ELM) predictor database. The putative D-box of Sp100 was verified by mutational analysis. Overexpression of Cdc20 resulted in decreased levels of both endogenous Sp100 protein and overexpressed Sp100 mRNA in HEK 293 cells. Only an overexpressed D-box deletion mutant of Sp100 accumulated in HEK293 cells that also overexpressed Cdc20. Cdc20 knockdown by cdc20 specific siRNA resulted in increased Sp100 protein levels in cells. Furthermore, we discovered that the Cdc20 mediated degradation of Sp100 is diminished by the proteasome inhibitor MG132, which suggests that the ubiquitination pathway is involved in this process. However, unlike the other Cdc20 substrates, which display oscillating protein levels, the level of Sp100 protein remains constant throughout the cell cycle. Additionally, both overexpression and knockdown of endogenous Sp100 had no effect on the cell cycle. Our results suggested that sp100 is a novel substrate of Cdc20 and it is degraded by the ubiquitination pathway. The intact D-box of Sp100 was necessary for this process. These findings expand our knowledge of both Sp100 and Cdc20 as well as their role in ubiquitination.

To characterize the in vitro bioactivities of rhodanine derivatives as novel peroxisome proliferator-activated receptor (PPAR) gamma modulators, based on a hit (SH00012671) identified during high-throughput screening (HTS) of a diverse synthetic compound library, and to preliminarily elucidate the structure-activity relationship of this class of PPARgamma agonists.Full-length PPARgamma and retinoid X receptor alpha (RXRalpha), biotinylated PPAR response element (PPRE), [3H]BRL49653 (rosiglitazone), and streptavidin-coated FlashPlate or microbeads were used to measure the receptor-binding properties of various compounds based on the scintillation proximity assay (SPA) technology. A recombinant PPRE vector was transiently cotransfected with PPARgamma and RXRalpha plasmids into the African green monkey kidney (CV-1) cells, and the effects of BRL49653 and test compounds on transcription mediated by PPARgamma were determined by examining luciferase (reporter) responses. 3T3-L1 cells were employed to determine whether the compounds facilitated adipogenesis upon PPARgamma activation.Of the 16,000 samples screened with the SPA method, only 1 compound (SH00012671) displayed a similar binding affinity (Ki=186.7 nmol/L) to PPARgamma as BRL49653, but it was inactive in the cell-based assays. A series of rhodanine derivatives were synthesized based on the core structure of SH00012671 and 8 of them showed agonist activities in both cotransfection and pre-adipocyte differentiation assays. To reduce intrinsic cytotoxicities, the sulphur on the rhodanine was changed to oxygen. This alteration led to a decrease in receptor-binding affinities while modified analogues generally maintained agonist efficacies in the cell-based assays. Of the analogues studied, compound 31 exhibited about 70% the efficacy exerted by BRL49653 in both cotransfection and pre-adipocyte differentiation assays.Through minor chemical modifications on the core structure of the initial HTS hit, SH00012671 was transformed to possess both molecular (PPARgamma binding) and cellular (adipogenesis) activities. The rhodanine derivatives reported here may represent a new scaffold in further understanding the molecular mechanism of agonism at PPARgamma.

To establish a 96-well plate based kinase assay using a recombinant vascular endothelial growth factor (VEGF) receptor 1 kinase domain protein.A human VEGF receptor 1 kinase domain protein was expressed in E coli, and its activity was monitored by its ability of phosphorylating the polyE4Y substrate coated on the walls of 96-well plates with antibody recognition and a colorimetric readout. A random screening of a sample organic compound library was carried out, and the hits were characterized with a transformed cell line stably expressing VEGF receptor 1 protein.An efficient E coli expression system for human VEGF receptor 1 kinase domain protein was constructed, and the purified recombinant protein was used to establish a practical screening assay for kinase inhibitors in vitro. Two thousand eight hundred organic compounds were screened, and two disubstituted furans (A1 and A5) with new structure showed inhibition of VEGF receptor 1 kinase. Compound A1 inhibited only phosphorylation of substrate, while compound A5 inhibited both autophosphorylation and substrate phosphorylation. Both inhibitors affected phosphorylation in the transformed cells.The recombinant receptor kinase based assay is simple and effective in identifying kinase inhibitors.