Metformin is a widely used biguanide drug for the treatment of type 2 diabetes. It has been revaluated as a potential anti-cancer drug with promising activity in various tumors. However, the precise mechanisms underlying the suppression of cancer cells by metformin remain not well understood.
In this study, human renal cell carcinoma cell line ACHN was used to investigate the anti-proliferation effect of metformin. A cell counting kit-8 assay was used to detect the cell viability. The cell cycle distribution and apoptosis were analyzed by flow cytometry. The expression of cyclin D1 and p27KIP1 was detected by Western blot. The underlying mechanism involving miRNA34a was further investigated by quantitative RT-PCR and transfection with miRNA inhibitor specific for miRNA34a in ACHN, 769-P, and A498 cells.
Metformin could significantly inhibit the proliferation of ACHN cells in a dose- and time-dependent manner. In addition, the results showed that metformin induced G0/G1 phase arrest and delayed entry into S phase in ACHN cells. It was shown that metformin downregulates the expression of cyclin D1 and increases the p27KIP1 level. Furthermore, metformin increased ACHN cell death. Lastly, miRNA34a was found to be upregulated by metformin in ACHN, 769-P, and A498 cells. Subsequently, it was demonstrated that inhibition of miRNA34a could partially attenuate the suppressive effect of metformin on renal cancer cell proliferation.
The study data revealed that metformin induced cell growth inhibition and cell cycle arrest partially by upregulating miRNA34a in renal cancer cells.
Cell Cycle; Cell Proliferation; Kidney Neoplasms; Metformin; MicroRNAs
Tea, a popular beverage made from leaves of the plant Camellia sinensis, has been shown to reduce body weight, alleviate metabolic syndrome, and prevent diabetes and cardiovascular diseases in animal models and humans. Such beneficial effects have generally been observed in most human studies when the level of tea consumption was 3 to 4 cups (600–900 mg tea catechins) or more per day. Green tea is more effective than black tea. In spite of numerous studies, the fundamental mechanisms for these actions still remain unclear. From a review of the literature, we propose that the two major mechanisms are: 1) decreasing absorption of lipids and proteins by tea constituents in the intestine, thus reducing calorie intake; and 2) activating AMPK by tea polyphenols that are bioavailable in the liver, skeletal muscle, and adipose tissues. The relative importance of these two mechanisms depends on the types of tea and diet consumed by individuals. The activated AMPK would decrease gluconeogenesis and fatty acid synthesis and increase catabolism, leading to body weight reduction and MetS alleviation. Other mechanisms and the health relevance of these beneficial effects of tea consumption remain to be further investigated.
AMPK; diabetes; EGCG; obesity; tea
Angiopoietin-1 (Ang1) is a critical factor for vascular stabilization and endothelial survival via inhibition of endothelial permeability and leukocyte- endothelium interactions. Hence, we hypothesized that treatment with umbilical cord mesenchymal stem cells (UCMSCs) carrying the Ang1 gene (UCMSCs-Ang1) might be a potential approach for acute lung injury (ALI) induced by lipopolysaccharide (LPS).
Materials and Methods
UCMSCs with or without transfection with the human Ang1 gene were delivered intravenously into rats one hour after intra-abdominal instillation of LPS to induce ALI. After the rats were sacrificed at 6 hours, 24 hours, 48 hours, 8 days, and 15 days post-injection of LPS, the serum, the lung tissues, and bronchoalveolar lavage fluid (BALF) were harvested for analysis, respectively.
Administration of fluorescence microscope confirmed the increased presence of UCMSCs in the injured lungs. The evaluation of UCMSCs and UCMSCs-Ang1 actions revealed that Ang1 overexpression further decreased the levels of the pro-inflammatory cytokines TNF-α, TGF-β1, and IL-6 and increased the expression of the anti-inflammatory cytokine IL-10 in the injured lungs. This synergy caused a substantial decrease in lung airspace inflammation and vascular leakage, characterized by significant reductions in wet/dry ratio, differential neutrophil counts, myeloperoxidase activity, and BALF. The rats treated by UCMSCs-Ang1 showed improved survival and lower ALI scores.
UCMSCs-Ang1 could improve both systemic inflammation and alveolar permeability in ALI. UC-derived MSCs-based Ang1 gene therapy may be developed as a potential novel strategy for the treatment of ALI.
Angiopoietin-1; human umbilical cord mesenchymal stem cell; acute lung injury
Atherosclerosis is an immune-mediated inflammatory process, which acts as the main cause of acute coronary syndrome (ACS). Regulatory CD4+CD25+FOXP3+T cells (Tregs) are thought to play a major role in inhibiting the formation and progression of atherosclerosis. However, the exact role played by Tregs in the pathogenesis of ACS is yet remained unclear. FOXP3 is a key regulator of Treg formation and function. Demethylation at the CpG-rich island of FOXP3 upstream enhancers can alter FOXP3 expression, and may affect Treg function during the development of ACS. This study investigated the immunosuppressive function and methylation status of a FOXP3 upstream enhancer in Tregs in ACS patients. Notably, Tregs from ACS patients exhibited a significantly lower immunosuppressive effect on Teffs. Furthermore, the methylation status of the FOXP3 upstream enhancer was significantly increased in ACS patients. Consistent with these observations, Tregs originated from ACS patients manifested significantly lower levels of FOXP3 mRNA. The immunosuppressive effect of Tregs on Teffs was compromised in ACS patients. Together, our data suggest that examination of the methylation status of the FOXP3 upstream enhancer might be a novel approach to diagnose ACS and to differentiate ACS subtypes.
Acute coronary syndrome; regulatory T cells; effector T cells; forkhead box P3; DNA methylation; immunosuppressive function
Nuclear factor E2-related factor 2 (NRF2) is a well-known master controller of the cellular adaptive antioxidant and detoxification response. Recent studies demonstrated altered glucose, lipid and energy metabolism in mice with a global Nrf2 knockout. In the present study, we aim to determine the effects of an adipose-specific ablation of Nrf2 (ASAN) on diet-induced obesity (DIO) in male mice. The 6-week-old adipose-specific Nrf2 knockout (NK) and its Nrf2 control (NC) mice were fed with either control diet (CD) or high-fat diet (HFD) for 14 weeks. NK mice exhibited transiently delayed body weight (BW) growth from week 5 to week 11 of HFD feeding, higher daily physical activity levels and preferential use of fat over carbohydrates as a source of energy at week 8 of the CD-feeding period. After 14 weeks of feeding, NK mice showed comparable results with NC mice with respect to the overall BW and body fat content, but exhibited reduced blood glucose, reduced number but increased size of adipocytes, accompanied with elevated expression of many genes and proteins in the visceral fat related to glucose, lipid and energy metabolism (e.g. Fgf21, Pgc1a). These results indicated that NRF2 is an important mediator for glucose, lipid and energy metabolism in adipose tissue, and ASAN could have beneficial effect for prevention of DIO during the early development of mice.
Adipose tissue; nuclear factor E2-related factor 2 (NRF2); glucose and lipid and energy metabolism; adipose-specific ablation of Nrf2; diet-induced obesity
Staphylococcus hyicus has caused great losses in the swine industry by inducing piglet exudative epidermitis (EE), sow mastitis, metritis, and other diseases and is a threat to human health. The pathogenesis of EE, sow mastitis, and metritis involves the interaction between the host and virulent protein factors of S. hyicus, however, the proteins that interact with the host, especially the host immune system, are unclear. In the present study, immunoproteomics was used to screen the immunogenic proteins of S. hyicus strain ZC-4. The cellular and secreted proteins of S. hyicus strain ZC-4 were obtained, separated by 2D gel electrophoresis, and further analyzed by western blot with S. hyicus strain ZC-4-infected swine serum. Finally, 28 specific immunogenic proteins including 15 cellular proteins and 13 secreted proteins, 26 of which were novel immunogenic proteins from S. hyicus, were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. To further verify their immunogenicity, two representative proteins (acetate kinase [cellular] and enolase [secreted]) were chosen for expression, and the resultant recombinant proteins could react with S. hyicus ZC-4-infected swine serum. In mice, both acetate kinase and enolase activated the immune response by increasing G-CSF and MCP-5 expression, and acetate kinase further activated the immune response by increasing IL-12 expression. Enolase can confer better protection against S.hycius than acetate kinase in mice. For the first time to our knowledge, our results provide detailed descriptions of the cellular and secreted proteins of S. hyicus strain ZC-4. These immunogenic proteins may contribute to investigation and elucidation of the pathogenesis of S. hyicus and provide new candidates for subunit vaccines in the future.
Background and Purpose
β‐Arrestins function as signal transducers linking GPCRs to ERK1/2 signalling either by scaffolding members of ERK1/2s cascades or by transactivating receptor tyrosine kinases through Src‐mediated release of transactivating factor. Recruitment of β‐arrestins to the activated GPCRs is required for ERK1/2 activation. Our previous studies showed that δ receptors activate ERK1/2 through a β‐arrestin‐dependent mechanism without inducing β‐arrestin binding to the δ receptors. However, the precise mechanisms involved remain to be established.
ERK1/2 activation by δ receptor ligands was assessed using HEK293 cells in vitro and male Sprague Dawley rats in vivo. Immunoprecipitation, immunoblotting, siRNA transfection, intracerebroventricular injection and immunohistochemistry were used to elucidate the underlying mechanism.
We identified a new signalling pathway in which recruitment of β‐arrestin2 to the EGFR rather than δ receptor was required for its role in δ receptor‐mediated ERK1/2 activation in response to H‐Tyr–Tic–Phe–Phe–OH (TIPP) or morphine stimulation. Stimulation of the δ receptor with ligands leads to the phosphorylation of PKCδ, which acts upstream of EGFR transactivation and is needed for the release of the EGFR‐activating factor, whereas β‐arrestin2 was found to act downstream of the EGFR transactivation. Moreover, we demonstrated that coupling of the PKCδ/EGFR/β‐arrestin2 transactivation pathway to δ receptor‐mediated ERK1/2 activation was ligand‐specific and the Ser363 of δ receptors was crucial for ligand‐specific implementation of this ERK1/2 activation pathway.
Conclusions and Implications
The δ receptor‐mediated activation of ERK1/2 is via ligand‐specific transactivation of EGFR. This study adds new insights into the mechanism by which δ receptors activate ERK1/2.
Multidrug resistance (MDR) is one of the most important contributors to the high mortality of cancer and remains a major concern. We previously found that zinc finger protein 32 (ZNF32), an important transcription factor associated with cancer in Homo sapiens, protects tumor cells against cell death induced by oxidative stress and other stimuli. We thus hypothesized that ZNF32 might enable the tolerance of cancer cells to anti-tumor drugs because higher ZNF32 expression has been found in cancer tissues and in drug-resistant lung adenocarcinoma (AC) cells. In this study, we found that ZNF32 is upregulated by Sp1 (specificity protein 1) in response to drug treatment and that ZNF32 promotes drug resistance and protects AC cells against cisplatin or gefitinib treatment. ZNF32 overexpression in AC cells conferred resistance to EGFR (epidermal growth factor receptor) inhibitors by enhancing MEK/ERK activation. Moreover, ZNF32 was found to directly bind to the TGF-βR2 (transforming growth factor-beta receptor 2) promoter to promote its expression, and ZNF32-induced resistance was mediated by enhancing TGF-βR2 expression and activating the TGF-βR2/SMAD2 pathway. In both a mouse model and ex vivo cultured patient samples, a high level of ZNF32 expression was closely associated with worse overall survival and cisplatin resistance. ZNF32 appears to be a potential inducer of drug resistance that could increase the expression of the drug resistance-associated gene TGF-βR2 and subsequently facilitate the induction of drug resistance during both conventional chemotherapy and novel target therapy. Thus, ZNF32-associated target therapy is a potential novel adjuvant therapy that might effectively prevent the occurrence of multidrug resistance (MDR) during chemotherapy and improve the survival of patients with AC.
After years of periconceptional folic acid supplementation, the prevalence of neural tube defects (NTDs) remains stable following the remarkable reduction observed immediately after the fortification practice. There is accumulating evidence that folate receptor (FR) autoimmunity may play a role in the etiology of folate-sensitive NTDs.
From 2011 to 2013, 118 NTD cases and 242 healthy controls were recruited from a population-based birth defects surveillance system in Northern China. Enzyme-linked immunosorbent assay was used to measure FR autoantibodies in maternal and cord blood. Logistic regression models were used to estimate the odds ratios (OR) and 95% confidence intervals (95% CI).
Plasma FR autoantibodies levels were significantly elevated in mothers of infants with NTDs compared with mothers of healthy controls. Using the lowest tertile as the referent group, 2.20-fold (95% CI, 0.71–6.80) and 5.53-fold increased odds (95% CI, 1.90–16.08) of NTDs were observed for the second and third tertile of immunoglobulin G (IgG), respectively, and the odds of NTDs for each successive tertile of IgM was 0.98 (95% CI, 0.35–2.75) and 3.49 (95% CI, 1.45–8.39), respectively. A dose–response relationship was found between FR autoantibodies levels and risk of NTDs (P < 0.001 for IgG, P = 0.002 for IgM). The same pattern was observed in both subtypes of spina bifida and anencephaly. No significant difference in levels of cord blood FR autoantibodies was observed.
Higher levels of FR autoimmunity in maternal plasma are associated with elevated risk of NTDs in a dose–response manner.
folate receptor; autoantibody; neural tube defects; IgG; IgM
In the present study we demonstrate for the first time that aging increases the levels of ubiquitinated protein in the spleen, and that dietary restriction (DR) significantly reduces these age-related increases in ubiquitinated protein. Sumoylated protein, proteasome subunits, and a protein essential for proteasome biogenesis (POMP1) were also increased with age in the spleen but were not significantly affected by DR. Chymotrypsin-like proteasome activity was elevated in the aged spleen, and was not significantly altered by DR. Together, these data demonstrate for the first time the multiple effects of aging and DR on ubiquitination, sumoylation, and the proteasome in the spleen.
Aging; POMP1; Proteasome; Spleen; Sumo; Ubiquitin
Biomedical big data, as a whole, covers numerous features, while each dataset specifically delineates part of them. “Full feature spectrum” knowledge discovery across heterogeneous data sources remains a major challenge. We developed a method called bootstrapping for unified feature association measurement (BUFAM) for pairwise association analysis, and relational dependency network (RDN) modeling for global module detection on features across breast cancer cohorts. Discovered knowledge was cross-validated using data from Wake Forest Baptist Medical Center’s electronic medical records and annotated with BioCarta signaling signatures. The clinical potential of the discovered modules was exhibited by stratifying patients for drug responses. A series of discovered associations provided new insights into breast cancer, such as the effects of patient’s cultural background on preferences for surgical procedure. We also discovered two groups of highly associated features, the HER2 and the ER modules, each of which described how phenotypes were associated with molecular signatures, diagnostic features, and clinical decisions. The discovered “ER module”, which was dominated by cancer immunity, was used as an example for patient stratification and prediction of drug responses to tamoxifen and chemotherapy. BUFAM-derived RDN modeling demonstrated unique ability to discover clinically meaningful and actionable knowledge across highly heterogeneous biomedical big data sets.
MicroRNAs (miRNAs) have been proved to play crucial roles in tumorigenesis. TGFβ signal pathway abnormality is found in various cancers and correlates with tumor proliferation and metastasis. However, the mechanisms underlying the dys-regulation of TGFβR2 expression in GC have not been investigated yet. In this study, we found that the TGFβR2 protein was clearly repressed in tumor tissues, while miR-130 expression level was dramatically increased in GC tissues. Firefly luciferase activity assay revealed that miR-130 could directly bind to 3′UTR of TGFβR2 mRNA. Meanwhile, miR-130 mimics lead to the decreased TGFβR2 protein levels, while miR-130 inhibitors enhanced TGFβR2 expression in SGC7901 cells. Subsequent functional experiments showed that overexpressed miR-130 could promote proliferation and migration of SGC7901 cells. And siRNA-mediated TGFβR2 down-regulation could simulate the effects of miR-130 mimics on phenotypes of SGC7901 cells. Furthermore, there existed intense relationship between the expression level of miR-130 and epithelial-mesenchymal markers. Our results demonstrated that miR-130 was an oncogene by directly targeting TGFβR2 in GC.
TGFβR2; miR-130; gastric cancer; proliferation; migration
Nowadays, the philosophy of treating metastatic breast cancer (MBC) is slowly evolving. Especially for the anthracycline- and taxane-pretreated MBC patients, no standard therapy exists in this setting. Whether to choose doublet agents or single agent as salvage treatment remains fiercely debated. Thus, we conducted a meta-analysis to resolve this problem. Databases including PubMed, EMBASE, and Cochrane library were searched for Phase III randomized clinical trials (published before August 2015) comparing the efficacy and adverse effects between the combination therapy and single-agent therapy in anthracycline- and taxane-pretreated MBC patients. The primary end point was the overall survival (OS), and the secondary end points were the progression-free survival (PFS), overall response rate (ORR), and grade 3 or 4 toxicities. The pooled hazard ratio (HR) and pooled risk ratio (RR) were used to evaluate the efficacy. Analyses were also performed to estimate the side effects and safety of both groups. In all, nine eligible randomized clinical trials were included in this meta-analysis. Improvements were proven in the doublet agents group on OS (HR 0.90, 95% confidence interval [CI] 0.84–0.96, P=0.002), PFS (HR 0.81, 95% CI 0.76–0.88, P<0.001), and ORR (RR 1.72, 95% CI 1.34–2.21, P<0.001). Notably, subgroup analysis failed to favor the targeted agent-based combination in terms of OS (HR 1.08, 95% CI 0.89–1.31, P=0.365), PFS (HR 1.09, 95% CI 0.88–1.35, P=0.433), and ORR (RR 1.60, 95% CI 0.69–3.71, P=0.278) compared with single agent. In addition, although more hematological and gastrointestinal toxicities were observed in the doublet agents group, they were acceptable and manageable. Taken together, when compared with single-agent therapy, doublet agents should be considered a treatment option because of the superior efficacy and the manageable safety profile for the prior anthracycline- and taxane-treated MBC patients.
breast cancer; anthracyclines; chemotherapy; combination therapy; toxicity
Most of the existing node depth-adjustment deployment algorithms for underwater wireless sensor networks (UWSNs) just consider how to optimize network coverage and connectivity rate. However, these literatures don’t discuss full network connectivity, while optimization of network energy efficiency and network reliability are vital topics for UWSN deployment. Therefore, in this study, a depth-adjustment deployment algorithm based on two-dimensional (2D) convex hull and spanning tree (NDACS) for UWSNs is proposed. First, the proposed algorithm uses the geometric characteristics of a 2D convex hull and empty circle to find the optimal location of a sleep node and activate it, minimizes the network coverage overlaps of the 2D plane, and then increases the coverage rate until the first layer coverage threshold is reached. Second, the sink node acts as a root node of all active nodes on the 2D convex hull and then forms a small spanning tree gradually. Finally, the depth-adjustment strategy based on time marker is used to achieve the three-dimensional overall network deployment. Compared with existing depth-adjustment deployment algorithms, the simulation results show that the NDACS algorithm can maintain full network connectivity with high network coverage rate, as well as improved network average node degree, thus increasing network reliability.
underwater wireless sensor networks (UWSNs); two-dimensional convex hull; spanning tree; time marker; network reliability; full network connectivity
Pathogenic bacteria could adjust gene expression to enable their survival in the distinct host environment. However, the mechanism by which bacteria adapt to the host environment is not well described. In this study, we demonstrated that nucleoside diphosphate kinase (Ndk) of Pseudomonas aeruginosa is critical for adjusting the bacterial virulence determinants during infection. Ndk expression was down-regulated in the pulmonary alveoli of a mouse model of acute pneumonia. Knockout of ndk up-regulated transcription factor ExsA-mediated T3S regulon expression and decreased exoproduct-related gene expression through the inhibition of the quorum sensing hierarchy. Moreover, in vitro and in vivo studies demonstrated that the ndk mutant exhibits enhanced cytotoxicity and host pathogenicity by increasing T3SS proteins. Taken together, our data reveal that ndk is a critical novel host-responsive gene required for coordinating P. aeruginosa virulence upon acute infection.
The correlation between impedance cardiography (ICG) and 6 min walk distance (6MWD) in atrial fibrillation (AF) patients remains unknown.
We recruited 49 subjects in the study (21 AF patients and 28 patients without AF) and estimated hemodynamic parameters: cardiac output (CO), stroke volume (SV), stroke volume index (SVI), left stroke work (LSW), left stroke work index (LSWI), stroke systemic vascular resistance (SSVR), stroke systemic vascular resistance index (SSVRI); 6MWD, left ventricle ejection fraction (LVEF), NT-pro brain natriuretic peptide (NT-pro BNP) for the two groups.
The AF group have apparently lower CO (2.26 ± 0.14 VS 4.11 ± 0.20 L/min, p = 0.039) and distinctly higher SVR (677.60 ± 69.10 VS 344.41 ± 22.98 dynes/cm5, p = 0.001), SSVRI (396.97 ± 36.80 VS 199.01 ± 11.72 dynes/cm5/m2, p < 0.001) than the control group. NT-pro BNP (1409.48 ± 239.90 VS 332.59 ± 68.85 pg/ml, p = 0.001) in the AF group was significantly higher than the control group and 6MWD (264.33 ± 14.55 VS 428.79 ± 29.98 m, p < 0.001) in the AF group was lower than the control group. There was no significant difference in LVEF between the two groups (62.67 ± 7.62 % VS 63.93 ± 5.03 %, p = 0.470). Pearson correlation analysis revealed that CO (R = 0.494, p = 0.023), SV (R = 0.633, p = 0.002), LSW (R = 0.615, p = 0.003) and LSWI (R = 0.491, p = 0.024) significantly correlated positively with 6MWD in AF patients.
AF patients had lower cardiac output, shorter 6MWD and higher NT-pro BNP than patients with sinus rhythm. The cardiac output measured by impedance cardiography significantly correlated positively with 6MWD in AF patients.
Impedance cardiography; 6 min walk distance; Atrial fibrillation
TGFBR2 serves as an initial regulator of the TGF-β signaling pathway, and loss or reduction of its expression leads to uncontrolled cell growth and invasion. TGFBR2 plays a crucial role in the carcinogenesis and malignant process of gastric cancer, but the mechanism remains unclear. In this study, we found that TGFBR2 protein levels were consistently upregulated in gastric cancer tissues, whereas TGFBR2 mRNA levels varied among these tissues, indicating that a post-transcriptional mechanism is involved in the regulation of TGFBR2. MiRNAs are known to regulate gene expression at the post-transcriptional level. Therefore, we performed bioinformatics analyses to search for miRNAs potentially targeting TGFBR2. MiR-17-5p was found to bind to the 3′UTR of TGFBR2 mRNA, and further validation of this specific binding was performed through a reporter assay. An inverse correlation between miR-17-5p and TGFBR2 protein was observed in gastric cancer tissues. Cell studies revealed that miR-17-5p negatively regulated TGFBR2 expression by directly binding to the 3′UTR of TGFBR2 mRNA, thereby promoting cell growth and migration. We also validated the role of TGFBR2 using siRNA and an overexpression plasmid. The results of our study suggest a novel regulatory network in gastric cancer mediated by miR-17-5p and TGFBR2 and may indicate that TGFBR2 could serve as a new therapeutic target in gastric cancer.
gastric cancer; TGFBR2; miR-17-5p; cell proliferation; migration
Agarwood, is a resinous portion derived from Aquilaria sinensis, has been widely used in traditional medicine and incense. 2-(2-phenylethyl)chromones are principal components responsible for the quality of agarwood. However, the molecular basis of 2-(2-phenylethyl)chromones biosynthesis and regulation remains almost unknown. Our research indicated that salt stress induced production of several of 2-(2-phenylethyl)chromones in A. sinensis calli. Transcriptome analysis of A. sinensis calli treated with NaCl is required to further facilitate the multiple signal pathways in response to salt stress and to understand the mechanism of 2-(2-phenylethyl)chromones biosynthesis.
Forty one 2-(2-phenylethyl)chromones were identified from NaCl-treated A. sinensis calli. 93 041 unigenes with an average length of 1562 nt were generated from the control and salt-treated calli by Illmunina sequencing after assembly, and the unigenes were annotated by comparing with the public databases including NR, Swiss-Prot, KEGG, COG, and GO database. In total, 18 069 differentially expressed transcripts were identified by the transcriptome comparisons on the control calli and calli induced by 24 h or 120 h salinity stress. Numerous genes involved in signal transduction pathways including the genes responsible for hormone signal transduction, receptor-like kinases, MAPK cascades, Ca2+ signal transduction, and transcription factors showed clear differences between the control calli and NaCl-treated calli. Furthermore, our data suggested that the genes annotated as chalcone synthases and O-methyltransferases may contribute to the biosynthesis of 2-(2-phenylethyl)chromones.
Salinity stress could induce the production of 41 2-(2-phenylethyl)chromones in A. sinensis calli. We conducted the first deep-sequencing transcriptome profiling of A. sinensis under salt stress and observed a large number of differentially expressed genes in response to salinity stress. Moreover, salt stress induced dynamic changes in transcript abundance for novel classes of responsive genes involved in signal transduction, including the genes responsible for hormone signal transduction, receptor-like kinases, MAPK cascades, Ca2+ signal transduction, and transcription factors. This study will aid in selecting the target genes to genetically regulate A. sinensis salt-stress signal transduction and elucidating the biosynthesis of 2-(2-phenylethyl)chromones under salinity stress.
Electronic supplementary material
The online version of this article (doi:10.1186/s12870-016-0803-7) contains supplementary material, which is available to authorized users.
Aquilaria sinensis; 2-(2-phenylethyl)chromones; Salinity stress; Transcriptome Differentially expressed gene; Signal transduction
Autophagy has been shown to be involved in the pathophysiology of developmental seizure-induced brain damage. The present study aimed to examine whether E-64d, an autophagy inhibitor, was able to facilitate developmental seizure-induced hippocampal mossy fiber sprouting, in particular sprouting-associated zinc transporter signals. Recurrent seizures were induced by penicillin every other day in Sprague-Dawley rats from postnatal day 21 (P21). Rats were randomly assigned into the control group (CONT), recurrent seizure group (RS) and the seizure plus E-64d group (E64D). The expression levels of beclin-1 and B-cell lymphoma 2 were analyzed at 1.5, 3, 6 and 24 h after the last seizures using western blot analysis. At P51, mossy fiber sprouting and the mRNA expression levels of zinc transporter 2 (ZnT-2), ZnT-4, ZnT-5, ZnT-6, ZnT-7, divalent cation transporter 1, Zrt-Irt-like protein 6 (ZIP-6), ZIP-7, cathepsin D and cathepsin L in the rat hippocampus were assessed using Timm staining and reverse transcription-quantitative polymerase chain reaction analysis, respectively. Reduced hippocampal mossy fiber sprouting were detected in the E-64d-treated rats compared with the non-treated control. In parallel with these observations, there was a marked reduction in the mRNA expression levels of ZnT-4 at P51 in the E-64d-treated rat hippocampus compared with the non-treated seizure group. Linear correlation analysis showed significant inter-relationship among ZIP-7, ZnT-4, ZnT-5, ZnT-7, cathepsin D and cathepsin L. These results indicate that the ZnT-4/ZIP-7/cathepsin signaling pathway serves a crucial function in the neuroprotective effects of E-64d. Thus, E-64d may offer a novel strategy for the development of therapeutic interventions for developmental seizure-induced brain damage.
zinc transporter; mossy fiber spouting; E-64d; developmental; seizure
We employed a high-throughput drug library screening platform to identify novel agents affecting thyroid cancer cells. We used human thyroid cancer cell lines to screen a collection of approximately 5200 small molecules with biological and/or pharmacologial properties. Parallel primary screens yielded a number of hits differentially active between thyroid and melanoma cells. Amongst compounds specifically targeting thyroid cancer cells, colchicine emerged as an effective candidate. Colchicine inhibited cell growth which correlated with G2 cell cycle arrest and apoptosis. These effects were hampered through inhibition of MEK1/2 and JNK. In contrast, inhibition of p38-MAPK had little effect, and AKT had no impact on colchicine action. Systemic colchicine inhibited thyroid cancer progression in xenografted mice. These findings demonstrate that our screening platform is an effective vehicle for drug reposition and show that colchicine warrants further attention in well-defined clinical niches such as thyroid cancer.
thyroid cancer; colchicine; BRAF; BRAF resistance; high throughput drug screening
Carcinosarcoma is a rare tumor consisting of epithelial and mesenchymal components, both of which are histologically malignant. It usually runs an aggressive clinical course, with higher metastatic potential than other kinds of carcinomas or sarcomas.
Here, we present an extremely uncommon case of carcinosarcoma occurred in the lesser omental bursa in a 65-year-old Chinese man. Metastasis was observed 2 months after operation and disappeared completely after chemotherapy. Until now, 3 years after surgery, the patient is still alive without any signs or symptoms of recurrence.
To our knowledge, this is the first case of carcinosarcoma originated from lesser omentum. Surgical resection and the ifosfamide-based combination chemotherapy may be effective to carcinosarcoma in the lesser omentum.
Bacterial cell division is a highly complex process that requires tight coordination between septum formation and chromosome replication and segregation. In bacteria that divide by binary fission a single septum is formed at mid-cell, a process that is coordinated by the conserved cell division scaffold protein FtsZ. In contrast, during sporulation-specific cell division in streptomycetes, up to a hundred rings of FtsZ (Z rings) are produced almost simultaneously, dividing the multinucleoid aerial hyphae into long chains of unigenomic spores. This involves the active recruitment of FtsZ by the SsgB protein, and at the same time requires sophisticated systems to regulate chromosome dynamics. Here, we show that SepG is required for the onset of sporulation and acts by ensuring that SsgB is localized to future septum sites. Förster resonance energy transfer imaging suggests direct interaction between SepG and SsgB. The beta-lactamase reporter system showed that SepG is a transmembrane protein with its central domain oriented towards the cytoplasm. Without SepG, SsgB fails to localize properly, consistent with a crucial role for SepG in the membrane localization of the SsgB–FtsZ complex. While SsgB remains associated with FtsZ, SepG re-localizes to the (pre)spore periphery. Expanded doughnut-shaped nucleoids are formed in sepG null mutants, suggesting that SepG is required for nucleoid compaction. Taken together, our work shows that SepG, encoded by one of the last genes in the conserved dcw cluster of cell division and cell-wall-related genes in Gram-positive bacteria whose function was still largely unresolved, coordinates septum synthesis and chromosome organization in Streptomyces.
cell division control; development; FtsZ; SsgA-like proteins
The aim of this study was to investigate the repair function of exogenous Endothelial progenitor cells (EPCs) for brain microvascular damage of the APP/PS1 transgenic mouse model of Alzheimer’s disease (AD). This study used a density-gradient centrifugation method to isolate mononuclear cells (MNCs) from mouse bone marrow, which were subsequently seeded and cultured. Cells were characterized by morphology and detection of the surface markers CD34 and CD133 at different time points by immunofluorescence (IF) and flow cytometry (FCM). Then, EPCs were transfected with GFP adenoviral vectors (GFP-EPCs). Wild-type (WT) and APP/PS1 transgenic mice both received GFP-EPCs injection through the tail vein, and using a PBS buffer injection as the control. Seven days later, the animals’ brain tissue was isolated. Expression of GFP was detected by quantitative polymerase chain reaction (qPCR) and western-blot (WB), while the fluorescence of GFP within the brains of mice was observed under a fluorescence microscope. Higher mRNA and protein expression of GFP, accompanied with increased green fluorescence, were detected in the brain of GFP-EPCs-injected APP/PS1 mice, as compared with GFP-EPCs-injected WT mice. The results show that the APP/PS1 transgenic mouse model of AD exhibited enhanced penetration of exogenous EPCs into brains than the WT mice.
APP/PS1 transgenic mouse model of AD; endothelial progenitor cells; penetration