Development and Validation of Ten-RNA Binding Protein Signature Predicts Overall Survival in Osteosarcoma

Osteosarcoma is a malignant tumor that originates in the bones with the characteristics of high malignancy, predisposition to metastasis, and poor prognosis. RNA binding proteins (RBPs) are closely related to various tumors, but their relationship with osteosarcoma remains unclear. Based on GTEx and TARGET RNA sequencing data, we applied differential analysis to obtain RBP genes that are differentially expressed in osteosarcoma, and analyzed the functions of these RBPs. After applying univariate and LASSO Cox regression analysis, 10 key prognostic RBPs (TDRD6, TLR8, NXT2, EIF4E3, RPS27L, CPEB3, RBM34, TERT, RPS29, and ZC3HAV1) were screened, and an RBP prognostic risk assessment model for patients with osteosarcoma was established. The independent cohort GSE21257 was used for external verification, and the results showed that the signature has an excellent ability to predict prognosis. In addition, a nomogram that can be used for clinical evaluation was constructed. Finally, the expression levels of 10 prognostic RBPs in osteosarcoma cells and tissues were confirmed through experiments. Our study identified a ten-gene prognostic marker related to RBP, which is of great significance for adjusting the treatment strategy of patients with osteosarcoma and exploring prognostic markers.

Clustered piperidinium-functionalized poly(terphenylene) anion exchange membranes with well-developed conductive nanochannels

Anion exchange membrane fuel cells (AEMFCs) attract considerable attention owing to their high-power density and potential utilization of cheap non-noble metal catalysts. However, anion exchange membranes (AEMs) still face the problems of low conductivity, poor dimensional and chemical stability. To address these issues, AEMs with clustered piperidinium groups and ether-bond-free poly(terphenylene) backbone (3QPAP-x, x = 0.3, 0.4, and 0.5) were designed. Transmission electron microscope results show that the clustered ionic groups are responsible for fabricating well-developed conductive nanochannels and restraining the swelling behavior of the membranes. 3QPAP-0.4 and 3QPAP-0.5 AEMs exhibit higher conductivity (117.5 mS cm^-1, 80 °C) and lower swelling ratio than that of commercial FAA-3-50 (80.4 mS cm^-1, 80 °C). The conductivity of 3QPAP-0.5 only decreased by 10.4% after treating with 1 M NaOH at 80 °C for 720 h. The Hofmann elimination degradation of the cationic groups is restrained by the long flexible alkyl chain between cations. Based on the high performance of 3QPAP-0.5, an H₂-O₂-type AEMFC reaches 291.2 mW cm^-2 (60 °C), which demonstrates that the as-prepared AEMs are promising for application in fuel cells.

High special surface area and "warm light" responsive ZnO: Synthesis mechanism, application and optimization

In this study, a new series of zinc oxide (ZnO) with high specific surface area and narrow energy band gap are prepared using a facile microwave-induced method. The corresponding formation mechanism is also discussed for the first time. Due to the introduction of C, these ZnO can be excited by long wave temperature light without harmful short wave radiation, and play an efficient photocatalytic activity. This valuable property fundamentally improves the biological safety of its photocatalytic application. Herein, taking teeth whitening as an example, the photocatalytic performance of ZnO is evaluated. The “pure” yellow light-emitting diode (PYLED) with high biological safety is used as the excitation source. It is found that this method could effectively remove pigment on the tooth surface through physical adsorption. In addition, these ZnO could generate active oxygen to degrade the pigment on the tooth surface under the irradiation of yellow light. Some further optimization of these “warm light” responsive ZnO is also discussed in this systematical study, which could open up new opportunities in biomedical field.

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A series of ZnO (PZCs, ZnO-BC) with high specific surface area and low band gap were synthesized by simple microwave-induced synthesis.

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The introduction of C or BC can effectively reduce the band gap of ZnO.

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Long wavelength warm light can effectively stimulate the photocatalytic activity of PZCs and ZnO-BC.

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Under the yellow light, ZnO can effectively decompose the pigment on the tooth surface.

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Warm light whitening, from the light source and material two levels to reduce the stimulation of teeth, and no obvious damage to enamel.

MiR-665 inhibits inflammatory response in microglia following spinal cord injury by targeting TREM2

OBJECTIVE

The purpose of this study was to uncover the role of microRNA-665 (miR-665) in protecting inflammatory response in microglia following spinal cord injury (SCI) and the underlying mechanism.

PATIENTS AND METHODS

The serum levels of miR-665 and TREM2 (triggering receptor expressed on myeloid 2) in SCI patients (n=24) and healthy subjects (n=24) were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Then, the serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay (ELISA). After lipopolysaccharide (LPS) induction in BV2 cells, the relative levels of miR-665 and TREM2 were detected by qRT-PCR, and relative levels of IL-6 and TNF-α in the culture medium were examined by ELISA. Next, TREM2, the target gene of miR-665, was determined by Dual-Luciferase reporter assay, and the relationship between the expression levels of TREM2 and miR-665 in SCI patients and BV2 cells was analyzed. Finally, the regulatory effects of miR-665 and TREM2 on IL-6 and TNF-α levels in the culture medium of LPS-induced BV2 cells were assessed.

RESULTS

It was found that miR-665 was downregulated in serum of SCI patients and LPS-induced BV2 cells, while TREM2 was upregulated. Silenced miR-665 or overexpressed TREM2 was involved in protecting inflammatory response following SCI. Besides, rescue experiments showed that miR-665 participated in the regulation of inflammatory response following SCI by targeting TREM2.

CONCLUSIONS

MiR-665 inhibits inflammatory response following SCI by targeting TREM2.

LncRNA MIR497HG inhibits proliferation and migration of retinal endothelial cells under high-level glucose treatment via miRNA-128-3p/SIRT1 axis

OBJECTIVE

The aim of this study was to elucidate the potential influence of MIR497HG on regulating proliferative capacity of human retinal endothelial cells (HRECs).

MATERIALS AND METHODS

Relative expression levels of MIR497HG, microRNA-128-3p (miRNA-128-3p) and SIRT1 in HRECs treated with different doses of glucose and mannitol were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Dual-Luciferase reporter gene assay was conducted to assess the interaction among MIR497HG, miRNA-128-3p, and SIRT1. In addition, the potential effects of MIR497HG/miRNA-128-3p/SIRT1 axis on proliferative and migratory capacities in HRECs were evaluated by Cell Counting Kit-8 (CCK-8), 5-Ethynyl-2'- deoxyuridine (EdU) and transwell assay, respectively.

RESULTS

High-level glucose (HG) treatment significantly downregulated MIR497HG and SIRT1 expression, whereas upregulated miRNA-128-3p expression in HRECs (p<0.05). MiRNA-128-3p was the target gene binding MIR497HG, and SIRT1 was the downstream gene of miRNA-128-3p. Overexpression of MIR497HG significantly attenuated proliferative and migratory abilities of HG-induced HRECs (p<0.05). Furthermore, decreased trends were partially reversed by overexpression of miRNA-128-3p or knockdown of SIRT1.

CONCLUSIONS

MIR497HG is downregulated after HG treatment. In addition, it suppresses the proliferation and migration of HRECs by targeting miRNA-128-3p/SIRT1 axis, thus influencing the progression of diabetic retinopathy.

Trichostatin A alleviates the process of breast carcinoma by downregulating LPAR5

OBJECTIVE

To elucidate the role of histone deacetylase inhibitor Trichostatin A (TSA) in affecting metastasis of breast carcinoma, and its molecular mechanism.

PATIENTS AND METHODS

LPAR5 levels in breast carcinoma tissues and paracancerous tissues were detected by quantitative real-time polymerase chain reaction (qRT-PCR), and its expression pattern was further verified in breast carcinoma cell lines. The relationship between LPAR5 and prognosis of breast carcinoma patients was analyzed. After TSA induction (100-400 nmol/L) for 6-48 h, the proliferative and migratory abilities of SKBR3 and MDA-MB-231 cells in overexpressing LPAR5 were examined by cell counting kit-8 (CCK-8), transwell and wound healing assay. By constructing a xenograft model in nude mice, the influences of TSA and LPAR5 on in vivo growth of breast carcinoma were examined.

RESULTS

LPAR5 was upregulated in breast carcinoma samples. High level of LPAR5 predicted higher rates of lymphatic metastasis and distant metastasis, as well as lower overall survival and progression-free survival in breast carcinoma patients. LPAR5 level was dose-dependently downregulated in TSA-induced SKBR3 and MDA-MB-231 cells. In addition, TSA induction dose-dependently declined proliferative ability, and time-dependently attenuated migratory ability in breast carcinoma cells. In vivo overexpression of LPAR5 in nude mice reversed the inhibitory effect of TSA on breast carcinoma growth.

CONCLUSIONS

TSA induction can suppress proliferative and migratory abilities in breast carcinoma by downregulating LPAR5.

Development and verification of an immune-related gene pairs prognostic signature in ovarian cancer

Ovarian cancer (OV) is the most common gynaecological cancer worldwide. Immunotherapy has recently been proven to be an effective treatment strategy. The work here attempts to produce a prognostic immune-related gene pair (IRGP) signature to estimate OV patient survival. The Gene Expression Omnibus (GEO) and Cancer Genome Atlas (TCGA) databases provided the genetic expression profiles and clinical data of OV patients. Based on the InnateDB database and the least absolute shrinkage and selection operator (LASSO) regression model, we first identified a 17-IRGP signature associated with survival. The average area under the curve (AUC) values of the training, validation, and all TCGA sets were 0.869, 0.712, and 0.778, respectively. The 17-IRGP signature noticeably split patients into high- and low-risk groups with different prognostic outcomes. As suggested by a functional study, some biological pathways, including the Toll-like receptor and chemokine signalling pathways, were significantly negatively correlated with risk scores; however, pathways such as the p53 and apoptosis signalling pathways had a positive correlation. Moreover, tumour stage III, IV, grade G1/G2, and G3/G4 samples had significant differences in risk scores. In conclusion, an effective 17-IRGP signature was produced to predict prognostic outcomes in OV, providing new insights into immunological biomarkers.

Comparing the Performance of Different Instruments for Diagnosing Frailty and Predicting Adverse Outcomes among Elderly Patients with Gastric Cancer

OBJECTIVES

To examine the diagnostic performance of the Tilburg Frailty Indicator (TFI), 11-factor modified frailty index (mFI-11), and 5-factor modified frailty index (mFI-5) for frailty defined by Frailty Phenotype (FP), as well as to compare the predictive ability of TFI, mFI-11, and mFI-5 for adverse outcomes in hospital among elderly patients undergoing gastric cancer surgery.

DESIGN

A prospective cohort study.

SETTING

Hospitalization setting, Nanjing, China.

PARTICIPANTS

We recruited 259 elderly patients undergoing gastric cancer surgery from a tertiary hospital.

MEASUREMENTS

Frailty was assessed by the FP, TFI, mFI-11, and mFI-5 before surgery, respectively. The receiver operating characteristic (ROC) curves were plotted to compared the diagnostic performance of TFI, mFI-11, and mFI-5 using FP as the reference. ROC curves were used to examine the performance of TFI, mFI-11, and mFI-5 in predicting adverse outcomes. The area under the curve (AUC)>0.70 was regarded as an indicator of good performance.

RESULTS

The prevalence of frailty ranged from 8.5% (mFI-11) to 45.9% (TFI). The AUCs of TFI (AUC: 0.764, p<0.001) was significantly greater than that of mFI-11 (AUC: 0.600, p=0.033) and mFI-5 (AUC: 0.600, p=0.0311) in the detection of frailty defined by FP, with quite different sensitivity and specificity at their original cutoffs. TFI and mFI-11 both had statistically significant but similarly inadequate predictive accuracy for adverse outcomes in hospital, including total complications (AUCs: 0.618; 0.621), PLOS (AUCs: 0.593; 0.639), increased hospital costs (AUCs: 0.594; 0.624), and hypoproteinemia (AUCs: 0.573; 0.600). For the mFI-5, only the predictive ability for hypoproteinemia was statistically significant, with poor accuracy (AUC: 0.592, p<0.0055).

CONCLUSION

The TFI performed slightly better than mFI-11 and mFI-5 in our study. Moreover, future studies are needed to further determine an optimal frailty instrument with great diagnostic and predictive accuracy.

A polymorphic MYC response element in KBTBD11 influences colorectal cancer risk, especially in interaction with an MYC-regulated SNP rs6983267

Background

MYC is a well-established cancer driver gene regulating the expression of numerous genes, indicating that polymorphisms in MYC response elements could affect tumorigenesis through altering MYC regulation. We performed integrative multistage study to evaluate the effects of variants in MYC response elements and colorectal cancer (CRC) risk.

Patients and methods

We systematically integrated ChIP-Seq, DNase-Seq and transcription factor motif data to screen variants with potential ability to affect the MYC binding affinity. Then, we conducted a two-stage case-control study, totally consisting of 4830 CRC cases and 4759 controls in Chinese population to identify risk polymorphisms and interactions. The effects of risk variants were confirmed by functional assays in CRC LoVo, SW480 and HCT15 cells.

Results

We identified a novel polymorphism rs11777210 in KBTBD11 significantly associated with CRC susceptibility (P = 2.43 × 10-12). Notably, we observed a significant interaction between rs11777210 and MYC nearby rs6983267 (P-multi = 0.003, P-add = 0.005), subjects carrying rs6983267 GG and rs11777210 CC genotypes showing higher susceptibility to CRC (2.83-fold) than those carrying rs6983267 TT and rs11777210 TT genotypes. We further demonstrated that rs6983267 T > G increased MYC expression, and MYC bound to and negatively regulated KBTBD11 expression when the rs11777210 C risk allele was present. KBTBD11 was downregulated in tumor tissues, and KBTBD11 knockdown promoted cell proliferation and inhibited cell apoptosis.

Conclusion

The rs11777210 is a potential predictive biomarker of CRC susceptibility, and KBTBD11 functions as a putative tumor suppressor in tumorigenesis. Our study highlighted the high CRC risk of people carrying rs6983267 G and rs11777210 C alleles, and provided possible biological mechanism of the interaction.

Localized Light-Au-Hyperthermia Treatment for Precise, Rapid, and Drug-Free Blood Clot Lysis

Thrombus diseases, induced by blood stasis or vascular embolization normally, frequently occur with high disability and mortalities worldwide. At present, drug thrombolysis, a primary clinical therapy for blood clot lysis, could increase the lethal risk for hemorrhage when thrombolysis agents are overused in the whole body. Therefore, a novel and advanced therapy for blood clot lysis, based on remote physical signals, is helpful for assisting clinical therapy. Here, we used the localized light-Au-hyperthermia (LAH) treatment, induced by gold nanorods (Au NRs) irradiated with near-infrared light (808 nm), for precise, rapid, and drug-free blood clot lysis. The LAH technology was first introduced in the murine hematoma model and the murine myocardial infarction model for blood clot lysis. Compared with traditional therapy, LAH was assured to shorten the time of detumescence in the murine hematoma model owing to their precise and localized hyperthermia. Meanwhile, we also discovered that LAH was a benefit to vascular recanalization in the murine myocardial infarction model. In addition, the Au NRs used in LAH present ideal biocompatibility in the murine model, which endows it to be suitable for blood clot lysis in vivo.

Thrombin-reduced miR-27b attenuates platelet angiogenic activities in vitro via enhancing platelet synthesis of anti-angiogenic thrombospondin-1

Essentials It is unclear if platelet micro-RNAs can regulate de novo protein synthesis of platelets. Platelet de novo protein synthesis of thrombospondin-1 (TSP-1) was induced by thrombin. Thrombin stimulation in vitro altered platelet microRNA profiles, including decreased miR-27b. Decreased miR-27b hampers platelet angiogenic activities via enhancing de novo TSP-1 synthesis.

SUMMARY

Background Platelets can synthesize proteins upon activation. Platelets contain a number of microRNAs (miRNA) and a fully functional miRNA effector machinery. It is, however, unclear if platelet miRNAs can regulate protein synthesis of platelets, and whether the regulation may produce a physiological impact. Objectives To investigate if and how platelet miRNAs regulate de novo syntheses of angiogenic regulators and subsequently modulate platelet angiogenic activities. Methods and Results Microarray-based miRNA profiling showed that thrombin stimulation in vitro down- or up-regulated a number of platelet miRNAs, both in the total platelet miRNAs and in Ago2-associated miRNAs. Among those altered miRNAs, miR-27b was down-regulated in both the total and Ago2-immunoprecipitated miRNA profiles of platelets, which was confirmed by reverse transcription-quantitative PCR (RT-qPCR). Using western blotting assays, we showed that thrombin induced platelet de novo synthesis of thrombospondin-1, and that the level of thrombospondin-1 synthesis could reach a level of 3-5-fold higher than that before thrombin stimulation. With either the platelet precursor megakaryocyte cell line MEG-01 cells or mature platelets, we demonstrated that transfection of miR-27b mimic, but not the negative control of miRNA mimic, markedly reduced thrombospondin-1 protein levels. The latter subsequently enhanced platelet-dependent endothelial tube formation on matrigel. Conclusions Thrombin stimulation in vitro reduces platelet miR-27b levels that may markedly enhance thrombin-evoked platelet de novo synthesis of thrombospondin-1. Elevation of platelet miR-27b by transfection inhibits thrombospondin-1 synthesis, and subsequently enhances platelet pro-angiogenic activities. Hence, platelet activation-dependent reduction of miR-27b levels may represent a novel negative regulatory mechanism of platelet angiogenic activities.

Percutaneous Endoscopic Spine Minimally Invasive Technique for Decompression Therapy of Thoracic Myelopathy Caused by Ossification of the Ligamentum Flavum

BACKGROUND

The percutaneous endoscopic technique through an interlaminar approach is a commonly used minimally invasive procedure in the treatment of lumbar disc herniation, even lumbar spinal stenosis. This report describes complete decompression with the percutaneous endoscopic technique for patients with thoracic ossification of the ligamentum flavum (OLF).

CASE DESCRIPTION

We performed surgical decompression in of 2 patients with thoracic myelopathy caused by OLF using percutaneous endoscopic surgery through an interlaminar approach. After surgery, the patients described significant improvement in their preoperative neurologic symptoms. Postoperative thoracic computed tomography showed that the ossification of ligaments was completely removed.

CONCLUSION

We applied the percutaneous endoscopic technique for the treatment of thoracic OLF accomplished direct decompression of the ossified ligaments with minimal trauma and instability. This technique could be used as an alternative choice. However, the fused types should be performed prudently because of the difficulties of the operation.

Inverse association between plasma homocysteine concentrations and type 2 diabetes mellitus among a middle-aged and elderly Chinese population

BACKGROUND AND AIMS

Plasma homocysteine concentrations have been reported to be associated with type 2 diabetes mellitus (T2DM) with controversial findings. The aim of the present study was to investigate the association between plasma homocysteine concentrations and T2DM.

METHODS AND RESULTS

A cross-sectional study including 19,085 eligible participants derived from the Dongfeng-Tongji cohort was conducted. Plasma homocysteine concentrations were measured by Abbott Architect i2000 Automatic analyzer and T2DM was defined according to American Diabetes Association criteria. Logistic regression model was used to explore the association between plasma homocysteine concentrations and T2DM. The prevalence of T2DM was 19.0% in the whole population (mean age 62.9 years), 21.8% in males, and 17.1% in females. In the multivariable logistic regression analyses, compared with those in the lowest quintile, the OR (95% CI) of T2DM was 1.05 (0.92-1.21), 0.99 (0.86-1.14), 0.90 (0.78-1.05), and 0.77 (0.66-0.90) for quintile 2 to quintile 5 of homocysteine concentrations after adjustment for potential confounders (P for trend < 0.0001). Homocysteine concentrations were associated with decreased T2DM prevalence risk (OR = 0.88 per SD increase of homocysteine concentration; 95% CI: 0.84-0.93). A significant interaction between homocysteine concentrations and drinking status on T2DM prevalence risk was observed (P for interaction = 0.03). The inverse association of plasma homocysteine concentrations with T2DM prevalence risk was observed in non-drinkers but not in current drinkers.

CONCLUSION

Plasma homocysteine concentrations were inversely correlated with T2DM among a middle-aged and elderly Chinese population.

Associations between daily cooking duration and the prevalence of diabetes and prediabetes in a middle-aged and elderly Chinese population: A cross-sectional study

Experimental and epidemiological studies indicated that ambient air pollution was positively associated with diabetes. Few studies investigated the associations between household air pollution, for example, daily cooking duration and diabetes or prediabetes. We conducted a cross-sectional study to investigate the associations of daily cooking duration with the prevalence of diabetes and prediabetes among a middle-aged and elderly population. A total of 26 089 individuals (11 250 males and 14 839 females) derived from the Dongfeng-Tongji cohort study were included. Daily cooking duration was assessed by questionnaire. Diabetes and prediabetes were identified according to the criterion of American Diabetes Association. No significant association was observed between daily cooking duration and the prevalence risk of diabetes (odds ratio[OR] = 0.97, 95% confidence interval[CI]: [0.81-1.16], P for trend = .74); however, longer daily cooking duration was associated with higher prevalence risk of prediabetes (OR = 1.26, 95% CI: 1.07-1.47; P for trend = .003) and hyperglycemia (OR = 1.21, 95% CI: 1.05-1.41; P for trend = .005). Our study suggested that daily cooking duration was not associated with diabetes but with higher prevalence risk of prediabetes/hyperglycemia in a middle-aged and elderly Chinese population.

Silver nanowire net knitted anisotropic aerogel as an ultralight and sensitive physiological activity monitor

A versatile and ultralight physiological activity monitor using celery derived inherent anisotropic aerogels with silver nanowire knitted net decoration.

BMI, Waist Circumference and All-Cause Mortality in a Middle-Aged and Elderly Chinese Population

OBJECTIVE

To investigate the association of obesity and all-cause mortality in a sample of middle-aged and elderly population.

DESIGN AND SETTING

Information of participants was collected in the Dongfeng-Tongji study, a perspective cohort study of Chinese occupational population. The main outcome was risk of death after 8.5 years of follow-up.

PARTICIPANTS AND MEASUREMENTS

We examined the association of BMI, waist circumference (WC, and waist-height ratio (WHtR) with all-cause mortality in the Dongfeng-Tongji cohort study (n=26,143). Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CI) for all-cause mortality. Area under the receiver operating characteristic curves and net reclassification improvement (NRI) were used to calculate the power of prediction models.

RESULTS

During a mean of 8.5 years of follow-up, 2,246 deaths were identified. There is a U-shaped association of BMI with all-cause mortality in the middle-aged and elderly Chinese population. Compared with individuals with normal BMI, underweight was positively (HR=2.16, 95% CI: 1.73, 2.69) while overweight (HR=0.75, 95% CI: 0.67, 0.84) and obesity (HR=0.67, 95% CI: 0.56, 0.79) were negatively associated with all-cause mortality after adjustment for potential confounders including WC. In contrast, WC (Q5 vs. Q1, HR=1.55, 95% CI: 1.29, 1.86) and WHtR (Q5 vs.Q1, HR=1.69, 95% CI: 1.40, 2.04) were positively associated with mortality after further adjustment for BMI (P trend < 0.001). Addition of both BMI and WC into the all-cause mortality predictive model significantly increased AUC (P =0.0002) and NRI (NRI = 2.57%, P = 0.0007).

CONCLUSIONS

BMI and WC/WHtR were independently associated with all-cause mortality after mutual adjustment. Combination of BMI and WC/WHtR improved the predictive ability of all-cause mortality risk in the middle-aged and elderly population.

Falling Leaves Inspired ZnO Nanorods-Nanoslices Hierarchical Structure for Implant Surface Modification with Two Stage Releasing Features

Inspired from falling leaves, ZnO nanorods-nanoslices hierarchical structure (NHS) was constructed to modify the surfaces of two widely used implant materials: titanium (Ti) and tantalum (Ta), respectively. By which means, two-stage release of antibacterial active substances were realized to address the clinical importance of long-term broad-spectrum antibacterial activity. At early stages (within 48 h), the NHS exhibited a rapid releasing to kill the bacteria around the implant immediately. At a second stage (over 2 weeks), the NHS exhibited a slow releasing to realize long-term inhibition. The excellent antibacterial activity of ZnO NHS was confirmed once again by animal test in vivo. According to the subsequent experiments, the ZnO NHS coating exhibited the great advantage of high efficiency, low toxicity, and long-term durability, which could be a feasible manner to prevent the abuse of antibiotics on implant-related surgery.

Isolation and characterization of microsatellite markers for Dendranthema morifolium (Asteraceae) using next-generation sequencing

Dendranthema morifolium (Asteraceae) is a perennial herbaceous plant native to China. A long history of artificial crossings may have resulted in complex genetic background and decreased genetic diversity. To protect the genetic diversity of D. morifolium and enabling breeding of new D. morifolium cultivars, we developed a set of molecular markers. We used pyrosequencing of an enriched microsatellite library by Roche 454 FLX+ platform, to isolate D. morifolium simple sequence repeats (SSRs). A total of 32,863 raw reads containing 2251 SSRs were obtained. To test the effectiveness of these SSR markers, we designed primers by randomly selecting 100 novel SSRs, and amplified them across 60 cultivars representing five different petal shape groups. Sixteen SSRs were polymorphic with the number of alleles ranging from 6 to 19, and their expected and observed heterozygosities ranging from 0.477 to 0.848, and 0.250 to 0.804, respectively. The polymorphism information content ranged from 0.459 to 0.854 and the inbreeding coefficient ranged from -0.119 to 0.759. An unweighted pair-group method arithmetic average analysis was performed to survey the phylogenetic relationships of these 60 cultivars and five clusters were identified. These markers can be used for investigating genetic relationships and identifying elite alleles through linkage and association analyses.

Comparison of ILK and ERP29 expressions in benign and malignant pancreatic lesions and their clinicopathological significances in pancreatic ductal adenocarcinomas

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant tumor of the pancreas with poor prognosis. The lack of understanding of the molecular mechanisms of PDAC and biomarkers for early diagnosis might be two of the reasons for the poor prognosis of PDAC.

MATERIALS AND METHODS

ILK and ERP29 protein expressions in PDAC, peritumoral tissues, benign pancreatic lesions, and normal pancreatic tissues were measured by immunohistochemistry and the clinical and pathological significances of ILK and ERP29 in PDAC were analyzed.

RESULTS

The percentages of positive ILK and negative ERP29 expressions were significantly higher in PDAC tumors than in peritumoral tissues, benign pancreatic tissues, and normal pancreatic tissues (P < 0.01). Benign pancreatic lesions with positive ILK and negative ERP29 expressions exhibited dysplasia or intraepithelial neoplasia. The percentage of cases with positive ILK and negative ERP29 expressions was significantly lower in PDAC patients without lymph node metastasis and invasion, and having TNM stage I/II disease than in patients with lymph node metastasis, invasion, and TNM stage III/IV disease (P < 0.05 or P < 0.01). Kaplan-Meier survival analysis showed that positive ILK and negative ERP29 expressions were significantly associated with survival in PDAC patients (P < 0.001). Cox multivariate analysis revealed that positive ILK and negative ERP29 expressions were independent poor prognosis factors in PDAC patients.

CONCLUSIONS

Positive ILK and negative ERP29 expressions are associated with the progression of PDAC and poor prognosis in patients with PDAC.

Hypoxia stimulates the proliferation of rat neural stem cells by regulating the expression of metabotropic glutamate receptors: an in vitro study

Neural stem cells (NSCs) reside in not only developing, but also adult brain with specialized microenvironments that regulate their function. In vitro and in vivo studies have revealed strong regulatory links between hypoxic/ischemic insults and activation of NSCs. However, the underlying mechanisms remain unclear. Here, we show that proliferating NSCs isolated from rat E15.5 cortex expressed functional metabotropic glutamate receptor (mGluR) subtype 3-7. Hypoxic exposure regulated their expression in NSCs in mRNA and protein levels. Activation of mGluRs by glutamate or Trans-ACPD (a non subtype-selective mGluRs agonist) sensitized NSCs to the growth effects of hypoxia. Pharmacological blockade of ionotropic glutamate receptor (iGluR) using MK-801 did not attenuate the action of glutamate in NSCs. Furthemore, we used the group specific mGluR agonists DHPG, LY 379268 and L-AP4 to explore which mGluR subtypes are responsible for stimulating NSCs proliferation after hypoxia. The results suggested that hypoxia increased expression of group I mGluR5 and significantly enhanced the NSCs proliferation. We conclude that hypoxia regulates the expression of mGluRs in proliferating NSCs and the dynamic expression of mGluRs induced by hypoxia may be one of the mechanisms of hypoxia stimulated NSCs activation. Regulation of mGluRs in NSCs might be a useful tool in the experimental cell therapy of hypoxic/ischemic injuries of CNS.

Tetraspanin CD151 and integrin α6β1 mediate platelet-enhanced endothelial colony forming cell angiogenesis

ESSENTIALS: Platelet releasates (PRs) enhance endothelial colony forming cell (ECFC) angiogenesis. The impact of platelet membrane components on ECFC angiogenesis was studied by a tube formation assay. Platelets enhanced ECFC angiogenesis more potently than PR, via tetraspanin CD151 and integrin α6β1. Optimal enhancement of ECFC angiogenesis by platelets requires both membrane proteins and PR.

SUMMARY

BACKGROUND

Platelets promote angiogenesis of endothelial colony forming cells (ECFCs), with the underlying mechanisms not being fully understood.

OBJECTIVE

To investigate if platelets regulate the angiogenic property of ECFCs via mechanisms beyond platelet-released angiogenic regulators.

METHODS AND RESULTS

Endothelial colony forming cells were generated by ECFC-directed cell culture of peripheral blood mononuclear cells. Capillary-like tube formation of ECFCs was assessed using a Matrigel assay. Platelets promoted ECFC tube formation in both basic and complete ECFC medium. Importantly, the ECFC angiogenic responses induced by platelets were stronger than those induced by platelet releasates. Thus, the branching points of ECFC tube formation (30.5 ± 9.0/field, ECFC alone) were increased by platelet releasates (58.2 ± 8.3/field) and even more profoundly by platelets (95.5 ± 17.6/field), indicating that platelet membrane components also promoted ECFC tube formation. The latter was further supported by evidence that fixed platelets did enhance ECFC tube formation. Subsequent experiments revealed that the promotion was dependent on platelet-surface glycoproteins, as removal of sialic acid from platelet glycoproteins by neuraminidase abolished the enhancement. Furthermore, platelet-expressed, but not ECFC-expressed, CD151 was important for the enhancement, as pretreatment of platelets, but not ECFCs, with a CD151-blocking antibody attenuated the effect. Integrin α6β1 on both ECFCs and platelets also participated in platelet-promoted tube formation, as integrin α6 or β1 blockade of either cell type markedly or totally inhibited the phenomenon. Moreover, platelets exerted the enhancement via the Src-PI3K signaling pathway of ECFCs.

CONCLUSION

Platelet-enhanced ECFC angiogenesis requires platelet tetraspanin CD151 and α6β1 integrin, as well as ECFC α6β1 integrin and Src-PI3K signaling.