Annexin A2 is a discriminative serological candidate in early hepatocellular carcinoma.

To date, the useful markers of hepatocellular carcinoma (HCC) remains incompletely developed. Here, we show that annexin A2 complement alpha-fetoprotein (AFP), a widely used liver cancer marker, in the serologically surveillance and early detection of HCC. First, differentially expressed proteins in HCC were identified using a subcellular proteomic approach. Annexin A2 was then selected for further verification. It was found to be overexpressed in HCC tissues (60.7%, 136/224). Using a self-established sandwich enzyme-linked immunosorbent assay, we found that annexin A2 significantly increased in the sera of HCC (n = 175, median, 24.75 ng/µl) compared with the healthy (n = 49, median, 16.69 ng/µl), benign tumors (n = 19, median, 19.92 ng/µl), hepatitis (n = 23, median, 6.48 ng/µl) and cirrhosis (n = 51, median, 7.39 ng/µl) controls and other malignant tumors (n = 87). Importantly, raised concentrations of annexin A2 were observed in 83.2% (79/95) of early stage (median, 24.32 ng/µl) and 78.4% (58/74) of AFP-negative (median, 24.09 ng/µl) patients. Annexin A2 alone had a better area under the receiver-operating characteristic curve (AUC = 0.79, 95% confidence interval: 0.73-0.85) in comparison with AFP (AUC = 0.73, 95% confidence interval: 0.66-0.80) in detecting of early stage HCC. Combining both markers notably improved the diagnostic efficiency of early HCC with an achieved sensitivity of 87.4%. Additionally, the expression characteristics of annexin A2 during hepatocarcinogenesis were detected in p21-HBx gene knockin transgenic mice model. The results showed that annexin A2 expression was substantially elevated in HCC-bearing mice, in accordance with the finding in human samples. In conclusion, annexin A2 may be an independent serological candidate for hepatitis B virus-related HCC, especially in the early stage cases with normal serum AFP.

XPS revelation of tungsten edges as a potential donor-type catalyst.

We report an efficient yet simple technology of photoelectron spectroscopic purification for identifying the capability of, and direction of charge flow in, a catalyst in a reaction, which has enabled the finding, for the first time, of the similarity of the valence band of tungsten edges to that of Rh adatoms and Ag/Pd alloy and hence suggested that W undercoordinated atoms could be a suitable candidate for replacing the costly Rh adatoms and Ag/Pd alloy as a cheaper, richer, and efficient donor-type catalyst for CO and NO oxidation applications. The new technology and new findings will be stimulating to the community for new catalyst design and identification and provide a better understanding of the electronic process of a catalytic reaction associated with undercoordinated atoms.

Down-regulation of RIP3 potentiates cisplatin chemoresistance by triggering HSP90-ERK pathway mediated DNA repair in esophageal squamous cell carcinoma.

Receptor interacting protein kinase 3 (RIP3) is a critical regulator of programmed necrotic cell death. Here, we observed that RIP3 was significantly down-regulated in esophageal cancer. And its remaining expression was associated with better response to chemotherapy and prolonged survival. Notably, re-expression of kinase-dead RIP3 also restored cisplatin sensitivity, suggesting that some roles of RIP3 beyond necroptosis may be involved in cisplatin-based chemosensitivity. To investigate the mechanisms, a large-scale quantitative proteomics study was performed after cisplatin treatment in RIP3-knockdown cells. In total, approximately 7000 protein groups were confidently identified, with a false discovery rate of 0.21% at the protein level. Of these proteins, 685 displayed RIP3-dependent changes in abundance. Bioinformatics analyses indicated that DNA repair pathway was stimulated after RIP3 depletion. Functional studies showed that deficient RIP3 upregulated FOSL1 and POLD1 through activation of the HSP90/CDC37 complex and ERK phosphorylation in multiple cell lines. Furthermore, via inhibition of the HSP90/CDC37 complex, ERK and FOSL1 reversed the cisplatin resistance phenotype. These results suggest that RIP3 regulates cisplatin sensitivity through both pronecrotic and non-necrotic functions. RIP3 may be a potential marker for predicting chemosensitivity.

KPNA2 is a promising biomarker candidate for esophageal squamous cell carcinoma and correlates with cell proliferation.

Esophageal squamous cell carcinoma (ESCC) is one of the most lethal malignant cancers worldwide, with a poor 5-year prognosis. Karyopherin α 2 (KPNA2) is a nuclear membrane protein that mediates nucleus-to-cytoplasm shuttling. Its expression is elevated in multiple forms of cancer, and it can be secreted into the serum. However, the concentration of KPNA2 in serum from ESCC patients and the role of KPNA2 in ESCC cells remains unclear. The aim of the present study was to determine the concentration of KPNA2 in serum from ESCC patients and to investigate the effect of KPNA2 silencing on ESCC cell proliferation. KPNA2 protein expression was detected at the tissue level by immunohistochemistry, in cell lines by western blotting and at the serum level by enzyme linked immunosorbent assay (ELISA). Cell proliferation was determined by cell growth curve and colony formation assay. Stages of the cell cycle were analyzed by flow cytometry. The effect of KPNA2 knockdown on E2F1 translocation was determined by subcellular fractionation. KPNA2 was overexpressed in both ESCC tissues and cell lines compared with controls. The concentration of KPNA2 in serum from ESCC patients was significantly higher than that from healthy controls. The AUC was determined to be 0.804. The sensitivity and specificity of the assay were 76.7 and 75.0%, respectively. To determine the significance of KPNA2 function, small interfering RNA (siRNA) against KPNA2 was used to knock down KPNA2 levels in the ESCC using siRNA in the Kyse510 cell line. KPNA2 siRNA inhibited Kyse510 cell proliferation and colony formation ability and induced a G2/M phase arrest. The nuclear translocation of E2F1 was also reduced in siRNA-treated Kyse510 cells. The KPNA2 protein levels were high in ESCC tumors, and siRNA against KPNA2 could inhibit the growth of ESCC cells, suggesting it may be a new potent marker and therapeutic target for ESCC.

[Recent advance in high accuracy iTRAQ for quantitative proteomics].

Nowadays, proteomics focuses on quantitative analysis rather than qualitative. In the field of quantitative proteomics, Isobaric tags for relative and absolute quantitation (iTRAQ) is one of the most widely used techniques. The advantage of iTRAQ is high throughput, high stability and free of the restriction of sample property. iTRAQ is suitable for almost all kinds of samples, and up to 8 samples can be analyzed simultaneously by commercially available kit. Along with the development of techniques, more and more mass spectrometry (MS) platforms are used in iTRAQ experiments and the accuracy of iTRAQ has been improved. iTRAQ has been applied to studies of microorganism, animal, plant, medical and protein post-translational modification. Here we review the recent progress in the development of iTRAQ and its applications in quantitative proteomics.

Interleukin-10 inhibits bone resorption: a potential therapeutic strategy in periodontitis and other bone loss diseases.

Periodontitis and other bone loss diseases, decreasing bone volume and strength, have a significant impact on millions of people with the risk of tooth loss and bone fracture. The integrity and strength of bone are maintained through the balance between bone resorption and bone formation by osteoclasts and osteoblasts, respectively, so the loss of bone results from the disruption of such balance due to increased resorption or/and decreased formation of bone. The goal of therapies for diseases of bone loss is to reduce bone loss, improve bone formation, and then keep healthy bone density. Current therapies have mostly relied on long-term medication, exercise, anti-inflammatory therapies, and changing of the life style. However there are some limitations for some patients in the effective treatments for bone loss diseases because of the complexity of bone loss. Interleukin-10 (IL-10) is a potent anti-inflammatory cytokine, and recent studies have indicated that IL-10 can contribute to the maintenance of bone mass through inhibition of osteoclastic bone resorption and regulation of osteoblastic bone formation. This paper will provide a brief overview of the role of IL-10 in bone loss diseases and discuss the possibility of IL-10 adoption in therapy of bone loss diseases therapy.

[Short gel method for pretreatment of protein samples with high concentration of detergent].

In proteomic research, to improve protein solubility of membrane proteins and nuclear proteins, buffers containing high concentration of detergent, such as 4% SDS, were widely used. However, high concentration of detergent might severely interfere with the downstream proteomic analysis, including protein quantitation and trypsin digestion. To improve the proteomic compatibility of buffers with high concentration of detergent, we used short gel method to pretreat buffers containing detergent. Protein samples were first separated by a short (2-2.5 mm) SDS-PAGE electrophoresis, and proteins were quantitated by comparing with bovine serum albumin standards via optical density analysis. The gel was then cut and peptides were recovered using in-gel digestion. The quantitative linearity range of this method was 1 to 8 µg. The quantitation was accurate and reproducible. After short gel analysis, recovered peptides generated high mass spectrometry signals. In conclusion, short gel method eliminated the interference of high concentration detergent in the proteomics analysis, and it was suitable for protein samples' pretreatment, and was worth to apply in proteomic research.

Expressions of interleukin-1ß and interleukin-6 within aortas and uteri of rats with various severities of ligature-induced periodontitis.

To investigate the associations of periodontitis with histological lesions in some other organs, various severities of periodontitis were induced in rats by 3/0 silk ligatures tied around different numbers of their molar necks. Six weeks after the initial placement of ligatures, all rats were sacrificed by an anaesthetic overdose. The distances from the cemento-enamel junction to the alveolar bone crest within the placement zone of the ligature and their contralateral zone in groups L(2) and L(3) were measured. The levels of interleukin (IL)-1ß and IL-6 in serum were assayed by enzyme-linked immunosorbent assay techniques, and those within aortas and uteri were measured by real-time polymerase chain reaction and by immunohistochemistry. We divided the ligature-induced periodontitis models into mild, moderate and severe rat periodontitis and observed that although no association between periodontitis and the serum concentrations of IL-1ß was detected, the differences in the severity of rat periodontitis led to varying degrees of elevated expressions of IL-1ß and IL-6 within aortas and uteri.

[Effect of desensitizer on shear bond strength of adhesive system].

OBJECTIVE: To evaluate the effect of desensitizer on shear bond strength of adhesive system. METHODS: Twenty specimens were made and divided randomly into an experiment group and a control group. In the experiment group, the dentin bonding surface was applied with Green Or and in the control, the dentin bonding surface was untreated. The IPS-Empress specimens were bonded to the dentin bonding specimens using Variolink II adhesive system. The shear bond strength of all testing samples was determined with Instron testing machine. The surfaces of the drawing sections were observed using the scanning electron microscope (SEM). RESULTS: The shear bond strength of the experimental group and the control group was (5.53 +/- 0.96) MPa and (7.32 +/- 1.34) MPa respectively and there was statistically significant difference between two groups (P = 0.003). In the experimental group, adhesive failure was the most prevalent type of failure, while in the control group, cohesive failure was the most prevalent type. CONCLUSIONS: The application of Green Or on the dentin bonding surface decreased the shear bond strength between dentin and IPS-Empress specimens when using Variolink II adhesive system.

[Quantitative study on occlusal balance of normal occlusion in intercuspal position].

OBJECTIVE: To assess occlusal balance of normal occlusion in intercuspal position with maximal bite force. METHODS: Maximal bite force was recorded in intercuspal position by use of T-Scan II system from 123 subjects with normal intact dentitions. Occlusal balance of normal occlusion was quantitatively analyzed from center of force, percentage of bite force, and occlusal contacts. RESULTS: The relative position of the center of bite force, the difference in bilateral force percentage, and unsymmetrical coefficient followed normal distributions. The 95% reference ranges for corresponding testing items were -6.60 to 6.68 mm, -15.50% to 12.10%, and 0.65 to 1.39. There was no statistic difference (P = 0.915) in occlusal contacts between left and right sides. The 98.4% of normal occlusion subjects had the center of bite force locating in posterior region of dentition when biting with maximal force in intercuspal position. CONCLUSIONS: Occlusal balance could be evaluated by T-Scan II system. Occlusion of normal subjects biting with maximal force was stable and bilaterally balanced in intercuspal position.