This study investigated the potential application of a zirconium oxide (ZrO2) ceramic foam culturing system to the production of glial cell line-derived neurotrophic factor (GDNF). Three sets of ZrO2 ceramic foams with different pore densities of 10, 20, and 30 pores per linear inch (PPI) were prepared to support a 3D culturing system. After primary astrocytes were cultured in these systems, production yields of GDNF were evaluated. The biomaterial biocompatibility, cell proliferation and activation of cellular signaling pathways in GDNF synthesis and secretion in the culturing systems were also assessed and compared with a conventional culturing system. In this study, we found that the ZrO2 ceramic foam culturing system was biocompatible, using which the GDNF yields were elevated and sustained by stimulated cell proliferation and activation of signaling pathways in astrocytes cultured in the system. In conclusion, the ZrO2 ceramic foam is promising for the development of a GDNF mass production device for Parkinson’s disease treatment.
Zirconium oxide; Ceramic foam; Glial cell line-derived neurotrophic factor (GDNF); Parkinson’s disease
The IL-33/ST2 signaling pathway plays an important role in coronary artery disease (CHD); however, few studies have explored how variants in IL-33/ST2 genes influence CHD risk. Here, we examined the association between genetic variants in IL-33, ST2, and IL-1RAcP of the IL-33/ST2 axis and the risk of CHD. We conducted a case-controlled study with 1146 CHD cases and 1146 age- and sex-frequency-matched controls. Twenty-eight single nucleotide polymorphisms (SNPs) in IL-33, ST2, and IL-1RAcP were genotyped by Sequenom MassArray and TaqMan assay. Logistic regression was used to analyze these associations. The SNP rs4624606 in IL-1RAcP was nominally associated with CHD risk. The AA genotype was associated with a 1.85-fold increased risk of CHD (95% confidence interval (CI) = 1.01–3.36; p = 0.045) compared to the TT genotype. Further analysis showed that AA carriers also had a higher risk of CHD than TT + TA carriers (odds ratio (OR) = 1.85; 95% CI = 1.85–3.35; p = 0.043). However, no significant association was observed between variants in IL-33/ST2 genes and CHD risk. Further studies are needed to replicate our results in other ethnic groups with larger sample size.
coronary artery disease; ST2; IL-33; IL-1RAcP; signaling pathway; gene
Bacteria affect oral health, but few studies have systematically examined the role of bacterial communities in oral diseases. We examined this relationship in a large population-based Chinese cancer screening cohort.
Human Oral Microbe Identification Microarrays were used to test for the presence of 272 human oral bacterial species (97 genera) in upper digestive tract (UDT) samples collected from 659 participants. Oral health was assessed using US NHANES (National Health and Nutrition Examination Survey) protocols. We assessed both dental health (total teeth missing; tooth decay; and the decayed, missing, and filled teeth (DMFT) score) and periodontal health (bleeding on probing (BoP) extent score, loss of attachment extent score, and a periodontitis summary estimate).
Microbial richness, estimated by number of genera per sample, was positively correlated with BoP score (P = 0.015), but negatively correlated with tooth decay and DMFT score (P = 0.008 and 0.022 respectively). Regarding β-diversity, as estimated by the UniFrac distance matrix for pairwise differences among samples, at least one of the first three principal components of the UniFrac distance matrix was correlated with the number of missing teeth, tooth decay, DMFT, BoP, or periodontitis. Of the examined genera, Parvimonas was positively associated with BoP and periodontitis. Veillonellacease [G-1] was associated with a high DMFT score, and Filifactor and Peptostreptococcus were associated with a low DMFT score.
Our results suggest distinct relationships between UDT microbiota and dental and periodontal health. Poor dental health was associated with a less microbial diversity, whereas poor periodontal health was associated with more diversity and the presence of potentially pathogenic species.
Electronic supplementary material
The online version of this article (doi:10.1186/1471-2458-14-1110) contains supplementary material, which is available to authorized users.
Microbiota; Oral health; Dental caries; Periodontitis; Bleeding on probe; Attachment loss
To compare the potential application of 99mTc-3P-Arg-Gly-Asp (99mTc-3P4-RGD2) scintimammography (SMM) and 99mTc-methoxyisobutylisonitrile (99mTc-MIBI) SMM for the differentiation of malignant from benign breast lesions.
Thirty-six patients with breast masses on physical examination and/or suspicious mammography results that required fine needle aspiration cytology biopsy (FNAB) were included in the study. 99mTc-3P4-RGD2 and 99mTc-MIBI SMM were performed with single photon emission computed tomography (SPECT) at 60 min and 20 min respectively after intravenous injection of 738±86 MBq radiotracers on a separate day. Images were evaluated by the tumor to non-tumor localization ratios (T/NT). Receiver operating characteristic (ROC) curve analysis was performed on each radiotracer to calculate the cut-off values of quantitative indices and to compare the diagnostic performance for the ability to differentiate malignant from benign diseases.
The mean T/NT ratio of 99mTc-3P4-RGD2 in malignant lesions was significantly higher than that in benign lesions (3.54±1.51 vs. 1.83±0.98, p<0.001). The sensitivity, specificity, and accuracy of 99mTc-3P4-RGD2 SMM were 89.3%, 90.9% and 89.7%, respectively, with a T/NT cut-off value of 2.40. The mean T/NT ratio of 99mTc-MIBI in malignant lesions was also significantly higher than that in benign lesions (2.86±0.99 vs. 1.51±0.61, p<0.001). The sensitivity, specificity and accuracy of 99mTc-MIBI SMM were 87.5%, 72.7% and 82.1%, respectively, with a T/NT cut-off value of 1.45. According to the ROC analysis, the area under the curve for 99mTc-3P4-RGD2 SMM (area = 0.851) was higher than that for 99mTc-MIBI SMM (area = 0.781), but the statistical difference was not significant.
99mTc-3P4-RGD2 SMM does not provide any significant advantage over the established 99mTc-MIBI SMM for the detection of primary breast cancer. The T/NT ratio of 99mTc-3P4-RGD2 SMM was significantly higher than that of 99mTc-MIBI SMM. Both tracers could offer an alternative method for elucidating non-diagnostic mammograms.
Wolbachia is the most prevalent symbiont described in arthropods to date. Wolbachia can manipulate host reproduction, provide nutrition to insect hosts and protect insect hosts from pathogenic viruses. So far, 13 supergroups of Wolbachia have been identified. The whitefly Bemisia tabaci is a complex containing more than 28 morphologically indistinguishable cryptic species. Some cryptic species of this complex are invasive. In this study, we report a comprehensive survey of Wolbachia in B. tabaci and its relative B. afer from 1658 insects representing 54 populations across 13 provinces of China and one state of Australia. Based on the results of PCR or sequencing of the 16S rRNA gene, the overall rates of Wolbachia infection were 79.6% and 0.96% in the indigenous and invasive Bemisia whiteflies, respectively. We detected a new Wolbachia supergroup by sequencing five molecular marker genes including 16S rRNA, groEL, gltA, hcpA, and fbpA genes. Data showed that many protein-coding genes have limitations in detecting and classifying newly identified Wolbachia supergroups and thus raise a challenge to the known Wolbachia MLST standard analysis system. Besides, the other Wolbachia strains detected from whiteflies were clustered into supergroup B. Phylogenetic trees of whitefly mitochondrial cytochrome oxidase subunit I and Wolbachia multiple sequencing typing genes were not congruent. In addition, Wolbachia was also detected outside the special bacteriocytes in two cryptic species by fluorescence in situ hybridization, indicating the horizontal transmission of Wolbachia. Our results indicate that members of Wolbachia are far from well explored.
Bemisia tabaci; FISH; horizontal transmission; multilocus sequence typing; vertical transmission; whiteflies; Wolbachia
NAD(H) kinase (NADK) is the key enzyme that catalyzes de novo synthesis of NADP(H) from NAD(H) for NADP(H)-based metabolic pathways. In plants, NADKs form functional subfamilies. Studies of these families in Arabidopsis thaliana indicate that they have undergone considerable evolutionary selection; however, the detailed evolutionary history and functions of the various NADKs in plants are not clearly understood.
We performed a comparative genomic analysis that identified 74 NADK gene homologs from 24 species representing the eight major plant lineages within the supergroup Plantae: glaucophytes, rhodophytes, chlorophytes, bryophytes, lycophytes, gymnosperms, monocots and eudicots. Phylogenetic and structural analysis classified these NADK genes into four well-conserved subfamilies with considerable variety in the domain organization and gene structure among subfamily members. In addition to the typical NAD_kinase domain, additional domains, such as adenylate kinase, dual-specificity phosphatase, and protein tyrosine phosphatase catalytic domains, were found in subfamily II. Interestingly, NADKs in subfamily III exhibited low sequence similarity (∼30%) in the kinase domain within the subfamily and with the other subfamilies. These observations suggest that gene fusion and exon shuffling may have occurred after gene duplication, leading to specific domain organization seen in subfamilies II and III, respectively. Further analysis of the exon/intron structures showed that single intron loss and gain had occurred, yielding the diversified gene structures, during the process of structural evolution of NADK family genes. Finally, both available global microarray data analysis and qRT-RCR experiments revealed that the NADK genes in Arabidopsis and Oryza sativa show different expression patterns in different developmental stages and under several different abiotic/biotic stresses and hormone treatments, underscoring the functional diversity and functional divergence of the NADK family in plants.
These findings will facilitate further studies of the NADK family and provide valuable information for functional validation of this family in plants.
For the study of information propagation, one fundamental problem is uncovering universal laws governing the dynamics of information propagation. This problem, from the microscopic perspective, is formulated as estimating the propagation probability that a piece of information propagates from one individual to another. Such a propagation probability generally depends on two major classes of factors: the intrinsic attractiveness of information and the interactions between individuals. Despite the fact that the temporal effect of attractiveness is widely studied, temporal laws underlying individual interactions remain unclear, causing inaccurate prediction of information propagation on evolving social networks. In this report, we empirically study the dynamics of information propagation, using the dataset from a population-scale social media website. We discover a temporal scaling in information propagation: the probability a message propagates between two individuals decays with the length of time latency since their latest interaction, obeying a power-law rule. Leveraging the scaling law, we further propose a temporal model to estimate future propagation probabilities between individuals, reducing the error rate of information propagation prediction from 6.7% to 2.6% and improving viral marketing with 9.7% incremental customers.
Hypertonic saline (HS) has been successfully used clinically for treatment of various forms of cerebral edema. Up-regulated expression of Na-K-Cl Cotransporter 1 (NKCC1) and inflammatory mediators such as tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) has been demonstrated to be closely associated with the pathogenesis of cerebral edema resulting from a variety of brain injuries. This study aimed to explore if alleviation of cerebral edema by 10% HS might be effected through down-regulation of inflammatory mediator expression in the microglia, and thus result in decreased NKCC1 expression in astrocytes in the cerebral cortex bordering the ischemic core.
The Sprague-Dawley (SD) rats that underwent right-sided middle cerebral artery occlusion (MCAO) were used for assessment of NKCC1, TNF-α and IL-1β expression using Western blotting, double immunofluorescence and real time RT-PCR, and the model also was used for evaluation of brain water content (BWC) and infarct size. SB203580 and SP600125, specific inhibitors of the p38 and JNK signaling pathways, were used to treat primary microglia cultures to determine whether the two signaling pathways were required for the inhibition of HS on microglia expressing and secreting TNF-α and IL-1β using Western blotting, double immunofluorescence and enzyme-linked immunosorbent assay (ELISA). The effect of TNF-α and IL-1β on NKCC1 expression in primary astrocyte cultures was determined. In addition, the direct inhibitory effect of HS on NKCC1 expression in primary astrocytes was also investigated by Western blotting, double immunofluorescence and real time RT-PCR.
BWC and infarct size decreased significantly after 10% HS treatment. TNF-α and IL-1β immunoexpression in microglia was noticeably decreased. Concomitantly, NKCC1 expression in astrocytes was down-regulated. TNF-α and IL-1β released from the primary microglia subjected to hypoxic exposure and treatment with 100 mM HS were decreased. NKCC1 expression in primary astrocytes was concurrently and progressively down-regulated with decreasing concentration of exogenous TNF-α and IL-1β. Additionally, 100 mM HS directly inhibited NKCC1 up-regulation in astrocytes under hypoxic condition.
The results suggest that 10% HS alleviates cerebral edema through inhibition of the NKCC1 Cotransporter, which is mediated by attenuation of TNF-α and IL-1β stimulation on NKCC1.
The majority of patients with BCR-ABL1-negative myeloproliferative neoplasms (MPN) harbor mutations in JAK2 or MPL, which lead to constitutive activation of the JAK/STAT, PI3K, and ERK signaling pathways. JAK inhibitors by themselves are inadequate in producing selective clonal suppression in MPN and are associated with hematopoietic toxicities. MK-2206 is a potent allosteric AKT inhibitor that was well tolerated, including no evidence of myelosuppression, in a phase I study of solid tumors. Herein, we show that inhibition of PI3K/AKT signaling by MK-2206 affected the growth of both JAK2V617F or MPLW515L-expressing cells via reduced phosphorylation of AKT and inhibition of its downstream signaling molecules. Moreover, we demonstrate that MK-2206 synergizes with Ruxolitinib in suppressing the growth of JAK2V617F mutant SET2 cells. Importantly MK-2206 suppressed colony formation from hematopoietic progenitor cells in patients with primary myelofibrosis (PMF) and alleviated hepatosplenomegaly and reduced megakaryocyte burden in the bone marrows, livers and spleens of mice with MPLW515L-induced MPN. Together, these findings establish AKT as a rational therapeutic target in the MPNs.
Myelofibrosis; PI3K; MPL; JAK2
The gut of phloem feeding insects is critical for nutrition uptake and xenobiotics degradation. However, partly due to its tiny size, genomic information for the gut of phloem feeding insects is limited.
In this study, the gut transcriptomes of two species of invasive whiteflies in the Bemisia tabaci complex, Middle East Asia Minor 1 (MEAM1) and Mediterranean (MED), were analyzed using the Illumina sequencing. A total of 12,879 MEAM1 transcripts and 11,246 MED transcripts were annotated with a significant Blastx hit. In addition, 7,000 and 5,771 gut specific genes were respectively identified for MEAM1 and MED. Functional analyses on these gut specific genes demonstrated the important roles of gut in metabolism of insecticides and secondary plant chemicals. To reveal the molecular difference between guts of MEAM1 and MED, a comparison between gut transcriptomes of the two species was conducted and 3,910 pairs of orthologous genes were identified. Based on the ratio of nonsynonymous and synonymous substitutions, 15 genes were found evolving under positive selection. Many of those genes are predicted to be involved in metabolism and insecticide resistance. Furthermore, many genes related to detoxification were expressed at an elevated level in the gut of MED compared to MEAM1, which might be responsible for the MED’s higher resistance to insecticides and environmental stresses.
The sequencing of MED and MEAM1 gut transcriptomes and extensive comparisons of MEAM1 and MED gut transcripts provide substantial sequence information for revealing the role of gut in whiteflies.
Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-370) contains supplementary material, which is available to authorized users.
Gene expression; Genetic divergence; Gut; Transcriptome; Whitefly
AIM: To explore whether routine biopsies at the high incidence spot of esophagogastric junction (EGJ) cancer are justified in endoscopic screening.
METHODS: This was a multicenter population-based study conducted in eight high-risk areas in China. A total of 37396 participants underwent endoscopic examination. Biopsies were obtained from visible mucosal abnormalities or from normal-appearing mucosa at the high incidence spot of esophagogastric junction cancer when no abnormality was detected. Specimens showing high-grade intraepithelial neoplasia (HIN) or higher grade lesions were deemed as pathologically “positive”. The ratios of positive pathologic diagnosis between participants with abnormal and normal-appearing mucosa were compared using the Pearson χ2 test. Odds ratios and 95% confidence intervals, adjusted for potential confounders, were calculated using logistic regression.
RESULTS: A total of 37520 individuals participated in this study and 37396 (99.7%) participants had full information and were suitable for analysis. During endoscopic examinations, 9.11% (3405/37396) participants were found to have visible mucosal lesions. Of the participants who had normal-appearing mucosa at the EGJ, only 0.28% (94/33991) were diagnosed with HIN or higher grade lesions, whereas 6.05% (206/3405) of participants with abnormalities at the EGJ had a positive pathologic result. After controlling for other variables, visible abnormal mucosa detected under endoscopy strongly predicted a positive pathologic result (OR = 32.51, 95%CI: 23.96-44.09). The proportion of participants with “positive” pathologic diagnoses increased as the total number of endoscopic examinations performed by the doctors increased (< 5000 cases vs 5000-10000 cases vs > 10000 cases, Z = -2.7207, P = 0.0065, Cochran Armiger trend test). The same trend was found between the proportion of participants with positive pathologic diagnoses and the total number of years the doctors performed endoscopy (< 5 years vs 5-10 years vs > 10 years, Z = -10.3222, P < 0.001, Cochran Armiger trend test).
CONCLUSION: Additional routine biopsies from the high incidence spot of EGJ cancer are of limited value and are unjustified.
Esophagogastric junction cancer; High incidence spot; Screening; Endoscopy; Biopsy
The whitefly, Bemisia tabaci, a notorious agricultural pest, has complex relationships with diverse microbes. The interactions of the whitefly with entomopathogens as well as its endosymbionts have received great attention, because of their potential importance in developing novel whitefly control technologies. To this end, a comprehensive understanding on the whitefly defense system is needed to further decipher those interactions.
We conducted a comprehensive investigation of the whitefly's defense responses to infection, via oral ingestion, of the pathogen, Pseudomonas aeruginosa, using RNA-seq technology. Compared to uninfected whiteflies, 6 and 24 hours post-infected whiteflies showed 1,348 and 1,888 differentially expressed genes, respectively. Functional analysis of the differentially expressed genes revealed that the mitogen associated protein kinase (MAPK) pathway was activated after P. aeruginosa infection. Three knottin-like antimicrobial peptide genes and several components of the humoral and cellular immune responses were also activated, indicating that key immune elements recognized in other insect species are also important for the response of B. tabaci to pathogens. Our data also suggest that intestinal stem cell mediated epithelium renewal might be an important component of the whitefly's defense against oral bacterial infection. In addition, we show stress responses to be an essential component of the defense system.
We identified for the first time the key immune-response elements utilized by B. tabaci against bacterial infection. This study provides a framework for future research into the complex interactions between whiteflies and microbes.
Aims. To evaluate the effects of globular adiponectin (gAd) on treatment of type 2 diabetic rats combined with NAFLD. Materials and Methods. Twenty-one male wistar rats were fed with normal diet (7 rats) or high fat diet (HFD) (14 rats) for 4 weeks, and then HFD-fed rats were injected with streptozotocin (STZ) to induce type 2 diabetes mellitus (T2DM). Half of T2DM rats were randomly injected with gAd intraperitoneally for 7 days. The expressions of adiponectin receptors (adipoR1/R2) in liver and skeletal muscle tissues were detected through western blotting or RT-qPCR, respectively. Results. Globular adiponectin alleviated the hepatic steatosis and increased insulin secretion. In liver, both the protein and mRNA expressions of adipoR2 in T2DM group decreased (P < 0.05, resp.) in contrast to NC group and increased (P < 0.05 and P < 0.001, resp.) after gAd treatment. But the protein and mRNA expressions of adipoR1 increased (P < 0.05, resp.) in T2DM group and no change was found in the gAd-treated group. In skeletal muscle, the protein and mRNA expressions of adipoR1 and adipoR2 were upregulated in T2DM group and were downregulated after gAd treatment. Conclusions. Globular adiponectin could ameliorate the hepatic steatosis and vary the expressions of adiponectin receptors in liver and skeletal muscle by stimulating insulin secretion.
Esophageal cancer is the sixth leading cause of cancer death worldwide; current early detection screening tests are inadequate. Esophageal balloon cytology successfully retrieves exfoliated and scraped superficial esophageal epithelial cells, but cytologic reading of these cells has poor sensitivity and specificity for detecting esophageal squamous dysplasia (ESD), the precursor lesion of esophageal squamous cell carcinoma (ESCC). Measuring telomere length, a marker for chromosomal instability, may improve the utility of balloon cytology for detecting ESD and early ESCC.
We examined balloon cytology specimens from 89 asymptomatic cases of ESD (37 low-grade and 52 high-grade) and 92 age- and sex-matched normal controls from an esophageal cancer early detection screening study. All subjects also underwent endoscopy and biopsy, and ESD was diagnosed histopathologically. DNA was extracted from the balloon cytology cells, and telomere length was measured by quantitative PCR. A receiver operating characteristic (ROC) curve was plotted for telomere length as a diagnostic marker for high-grade dysplasia.
Telomere lengths were comparable among the low- and high-grade dysplasia cases and controls, with means of 0.96, 0.96, and 0.92, respectively. The area under the ROC curve was 0.55 for telomere length as a diagnostic marker for high-grade dysplasia. Further adjustment for subject characteristics, including sex, age, smoking, drinking, hypertension, and body mass index did not improve the use of telomere length as a marker for ESD.
Telomere length of esophageal balloon cytology cells was not associated with ESCC precursor lesions. Therefore, telomere length shows little promise as an early detection marker for ESCC in esophageal balloon samples.
Esophageal squamous cell carcinoma; Esophageal squamous dysplasia; Early detection; Screening; Balloon cytology; Telomeres
Merkel cell carcinoma (MCC) is an aggressive cutaneous malignancy, but little is known about the presence or characteristics of MCC in mainland China. A retrospective chart review was conducted to describe the clinical profile of Merkel cell carcinoma in China.
At 18 cancer or dermatology hospitals in metropolitan centers from the six geographical regions of mainland China, approximately 3,100,000 pathology database and medical records were searched for cases that had a pathological diagnosis of MCC between 1970 and 2009. A case series was compiled from retrospective chart reviews of identified MCC patients.
Eight out of 18 participating hospitals reported at least one record of a patient with a pathological diagnosis of MCC, and a total of 22 cases were identified. The median age of patients was 65.5, and 59% were female. The median time from the appearance of a lesion to the time of biopsy was 6 months, and the most common location of lesions was the head and neck. The most common treatment used was surgery alone.
MCC appears to be uncommon in mainland China. Patients in this series are elderly, often had lesions on the head/neck region, and most commonly received surgery alone as treatment. In contrast with MCC in Western countries, the current series' patients were all of Asian ethnicity, had larger lesions at presentation, and none were documented as having HIV or other forms of immunosuppression.
Merkel cell carcinoma; China; skin cancer; case-series
The mechanism by which cells decide to skip mitosis to become polyploid is largely undefined. Here we used a high-content image-based screen to identify small-molecule probes that induce polyploidization of megakaryocytic leukemia cells and serve as perturbagens to help understand this process. We found that dimethylfasudil (diMF, H-1152P) selectively increased polyploidization, mature cell-surface marker expression, and apoptosis of malignant megakaryocytes. A broadly applicable, highly integrated target identification approach employing proteomic and shRNA screening revealed that a major target of diMF is Aurora A kinase (AURKA), which has not been studied extensively in megakaryocytes. Moreover, we discovered that MLN8237 (Alisertib), a selective inhibitor of AURKA, induced polyploidization and expression of mature megakaryocyte markers in AMKL blasts and displayed potent anti-AMKL activity in vivo. This research provides the rationale to support clinical trials of MLN8237 and other inducers of polyploidization in AMKL. Finally, we have identified five networks of kinases that regulate the switch to polyploidy.
Linzhou, China has one of the highest rates of esophageal squamous cell carcinoma in the world. Exposure to carcinogenic polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene (BaP), may play a role in this increased risk. To better understand PAH sources, we measured PAHs in the air and food of 20 non-smokers over multiple days and compared the concentrations to a urinary PAH biomarker, 1-hydroxypyrene glucuronide (1-OHPG). Sampling occurred over four consecutive days. Kitchen air samples (days 2–3) and duplicate diet samples (days 1–4) were analyzed for 14 or more unique PAHs, including BaP. Daily urine samples (days 1–3) were analyzed for 1-OHPG. Mixed-effects models were used to evaluate the associations between air or food PAH concentrations and urine 1-OHPG concentrations. The median kitchen air BaP concentration was 10.2 ng/m3 (inter-quartile range (IQR): 5.1–20.2 ng/m3). The median daily food BaP concentration and intake were 0.08 ng/g (IQR=0.04–0.16 ng/g) and 86 ng/day (IQR=41–142 ng/day), respectively. The median 1-OHPG concentration was 3.36 pmol/mL (IQR=2.09–6.98 pmol/mL). In mixed-effects models, 1-OHPG concentration increased with same-day concentration of food BaP (p=0.07). Though PAH concentrations in air were not associated with 1-OHPG concentrations, the high concentrations of PAHs in both air and food suggest that they are both important routes of exposure to PAHs in this population. Further evaluation of the role of PAH exposure from air and food in the elevated rates of esophageal cancer in this region is warranted.
polycyclic aromatic hydrocarbons; cancer; China; dietary exposure; inhalation exposure; biomonitoring; multimedia exposure assessment
We used large samples of expressed sequence tags to characterize the patterns of codon usage bias (CUB) in seven different Citrus species and to analyze their evolutionary effect on selection and base composition. We found that A- and T-ending codons are predominant in Citrus species. Next, we identified 21 codons for 18 different amino acids that were considered preferred codons in all seven species. We then performed correspondence analysis and constructed plots for the effective number of codons (ENCs) to analyze synonymous codon usage. Multiple regression analysis showed that gene expression in each species had a constant influence on the frequency of optional codons (FOP). Base composition differences between the proportions were large. Finally, positive selection was detected during the evolutionary process of the different Citrus species. Overall, our results suggest that codon usages were the result of positive selection. Codon usage variation among Citrus genes is influenced by translational selection, mutational bias, and gene length. CUB is strongly affected by selection pressure at the translational level, and gene length plays only a minor role. One possible explanation for this is that the selection-mediated codon bias is consistently strong in Citrus, which is one of the most widely cultivated fruit trees.
citrus; codon usage; evolution
Plasma membrane NADPH oxidases (Noxs) are key producers of reactive oxygen species under both normal and stress conditions in plants. We demonstrate that at least eleven genes in the genome of rice (Oryza sativa L.) were predicted to encode Nox proteins, including nine genes (OsNox1–9) that encode typical Noxs and two that encode ancient Nox forms (ferric reduction oxidase 1 and 7, OsFRO1 and OsFRO7). Phylogenetic analysis divided the Noxs from nine plant species into six subfamilies, with rice Nox genes distributed among subfamilies I to V. Gene expression analysis using semi-quantitative RT-PCR and real-time qRT-PCR indicated that the expression of rice Nox genes depends on organs and environmental conditions. Exogenous calcium strongly stimulated the expression of OsNox3, OsNox5, OsNox7, and OsNox8, but depressed the expression of OsFRO1. Drought stress substantially upregulated the expression of OsNox1–3, OsNox5, OsNox9, and OsFRO1, but downregulated OsNox6. High temperature upregulated OsNox5–9, but significantly downregulated OsNox1–3 and OsFRO1. NaCl treatment increased the expression of OsNox2, OsNox8, OsFRO1, and OsFRO7, but decreased that of OsNox1, OsNox3, OsNox5, and OsNox6. These results suggest that the expression profiles of rice Nox genes have unique stress-response characteristics, reflecting their related but distinct functions in response to different environmental stresses.
NADPH oxidase (Nox); phylogenetic analysis; gene expression; environmental stress; rice (Oryza sativa)
A CBFA2T3-GLIS2 fusion gene was identified in 31% of non–Down syndrome AMKL.
Acute megakaryoblastic leukemia (AMKL) is a heterogeneous disease generally associated with poor prognosis. Gene expression profiles indicate the existence of distinct molecular subgroups, and several genetic alterations have been characterized in the past years, including the t(1;22)(p13;q13) and the trisomy 21 associated with GATA1 mutations. However, the majority of patients do not present with known mutations, and the limited access to primary patient leukemic cells impedes the efficient development of novel therapeutic strategies. In this study, using a xenotransplantation approach, we have modeled human pediatric AMKL in immunodeficient mice. Analysis of high-throughput RNA sequencing identified recurrent fusion genes defining new molecular subgroups. One subgroup of patients presented with MLL or NUP98 fusion genes leading to up-regulation of the HOX A cluster genes. A novel CBFA2T3-GLIS2 fusion gene resulting from a cryptic inversion of chromosome 16 was identified in another subgroup of 31% of non–Down syndrome AMKL and strongly associated with a gene expression signature of Hedgehog pathway activation. These molecular data provide useful markers for the diagnosis and follow up of patients. Finally, we show that AMKL xenograft models constitute a relevant in vivo preclinical screening platform to validate the efficacy of novel therapies such as Aurora A kinase inhibitors.
Tumor-associated macrophages have been shown to promote tumor growth. They may have an obligatory function in angiogenesis, invasion, and metastasis through release of inflammatory mediators. Their presence in ovarian cancer has been correlated with poor prognosis in these patients. The human cationic antimicrobial protein-18 (hCAP18)/LL-37 was originally identified as an effector molecule of the innate immune system. It is released by innate immune cells, such as macrophages, to combat microorganisms. Previous studies have characterized the hCAP18/LL-37 as a growth factor that has been shown to promote ovarian tumor progression. However, the role hCAP18/LL-37 has in macrophage-promoted ovarian tumor development and how its expression is controlled in this context remains poorly understood. Here, we demonstrate in co-culture experiments of macrophages and ovarian cancer cells a significant increase in the in vitro proliferation and invasiveness of the tumor cells is observed. These enhanced growth and invasion properties correlated with hCAP18/LL-37 induction. HCAP18/LL-37 expression was diminished by addition of two neutralizing antibodies, TLR2 or TLR6, as well as Cyp27B1 or VDR inhibitors. Furthermore, either the TLR2 or TLR6 antibody reduced vitamin D3 signaling and tumor cell progression in vitro. Addition of Cyp27B1 or VDR inhibitors abrogated TLR2/6 activation-induced expression of hCAP18/LL-37 in macrophages. Knockdown of tumor-produced versican V1 by RNAi in these tumor cells led to a decreased induction of hCAP18/LL-37 in macrophages. Versican V1 knockdown also inhibited TLR2 and vitamin D3 signaling, as well as growth and invasiveness of these tumor cells in the in vitro co-culture. In summary, we have found that versican V1 enhances hCAP18/LL-37 expression in macrophages through activation of TLR2 and subsequent vitamin D-dependent mechanisms which promote ovarian tumor progression in vitro.
Uncovering factors underlying the network formation is a long-standing challenge for data mining and network analysis. In particular, the microscopic organizing principles of directed networks are less understood than those of undirected networks. This article proposes a hypothesis named potential theory, which assumes that every directed link corresponds to a decrease of a unit potential and subgraphs with definable potential values for all nodes are preferred. Combining the potential theory with the clustering and homophily mechanisms, it is deduced that the Bi-fan structure consisting of 4 nodes and 4 directed links is the most favored local structure in directed networks. Our hypothesis receives strongly positive supports from extensive experiments on 15 directed networks drawn from disparate fields, as indicated by the most accurate and robust performance of Bi-fan predictor within the link prediction framework. In summary, our main contribution is twofold: (i) We propose a new mechanism for the local organization of directed networks; (ii) We design the corresponding link prediction algorithm, which can not only testify our hypothesis, but also find out direct applications in missing link prediction and friendship recommendation.
CDA-2 (cell differentiation agent 2), a urinary preparation, has potent anti- proliferative and pro-apoptotic properties in cancer cells. However, the mechanisms of tumor inhibitory action of CDA-2 are far from clear, and especially there was no report on lung cancer. Here we demonstrate that CDA-2 and its main component phenylacetylglutamine (PG) reduce the metastatic lung tumor growth, and increases survival time after inoculation with Lewis lung carcinoma (LLC) cells in a dose-dependent manner in C57BL6 mice. Proliferative program analysis in cancer cells revealed a fundamental impact of CDA-2 and PG on proliferation and apoptosis, including Bcl-2, Bcl-XL, cIAP1, Survivin, PCNA, Ki-67 proteins and TUNEL assays. CDA-2 and PG significantly reduced NF-κB DNA-binding activity in lung cancer cells and in alveolar macrophages of tumor bearing mice and especially decreased the release of inflammatory factors including TNFα, IL-6, and KC. Furthermore, CDA-2 and PG decrease the expressions of TLR2, TLR6, and CD14, but not TLR1, TLR3, TLR4, and TLR9 in bone-marrow-derived macrophages (BMDM) of mice stimulated by LLC-conditioned medium (LLC-CM). Over-expressing TLR2 in BMDM prevented CDA-2 and PG from inhibiting NF-κB activation, as well as induction of TNFα and IL-6. TLR2:TLR6 complexes mediate the effect of NF-κB inactivation by CDA-2. In conclusion, CDA-2 potently inhibits lung tumor development by reduction of the inflammation in lung through suppression of NF-κB activation in myeloid cells, associating with modulation of TLR2 signaling.
We show constitutive activation of Rho kinase (ROCK) in cells bearing oncogenic forms of KIT, FLT3 and BCR-ABL, which is dependent on PI3K and Rho GTPase. Genetic or pharmacologic inhibition of ROCK in oncogene bearing cells impaired their growth as well as the growth of acute myeloid leukemia patient derived blasts and prolonged the life span of mice bearing myeloproliferative disease. Downstream from ROCK, rapid dephosphorylation or loss of expression of myosin light chain resulted in enhanced apoptosis, reduced growth and loss of actin polymerization in oncogene bearing cells leading to significantly prolonged life span of leukemic mice. In summary, we describe a pathway involving PI3K/Rho/ROCK/MLC which may contribute to myeloproliferative disease and/or acute myeloid leukemia in humans.