Cationic ribosomal proteins can inhibit pro-inflammatory action stimulated by LPS+HMGB1 and are hindered by advanced glycation end products.

We previously found that ribosomal protein L9 (RPL9) is a novel advanced glycation end product (AGE)-binding protein that can decrease pro-inflammatory TNF-α expression stimulated by lipopolysaccharide (LPS) plus high-mobility group box 1 (HMGB1), suggesting that RPL9 has a role in regulating LPS+HMGB1-stimulated inflammatory reactions. Among the various ribosomal proteins, it was found that RPS5 reproduced the regulatory activity of RPL9 on LPS+HMGB1-stimulated TNF-α expression in macrophage-like RAW264.7 cells. RPL9 and RPS5 share a common feature as cationic proteins. Polylysine, a cationic polypeptide, and a synthetic peptide of the cationic region from RPL9 also exhibited reducing activity on LPS+HMGB1-induced TNF-α expression. By pull-down assay, RPL9 and RPS5 were confirmed to interact with AGEs. When AGEs coexisted with LPS, HMGB1, plus RPL9 or RPS5, the reducing effect of TNF-α expression by these cationic ribosomal proteins was shown to be abrogated. The results suggest that cationic ribosomal proteins have a regulatory role in the pro-inflammatory response induced by LPS+HMGB1, and in the pathophysiological condition of accumulating AGEs, this regulatory effect is abolished, which exacerbates inflammation.

Root canal morphology of mandibular anterior permanent teeth in Turkish sub-population using two classification systems: a cone-beam computed tomography study.

This study examined the root and canal morphology of mandibular anterior teeth (MA) in the Turkish sub-population using cone-beam computed tomography (CBCT), comparing the findings based on Vertucci's and Ahmed et al. classification systems. The CBCT images were acquired using the 3D Accuitomo CBCT device. Images that were deemed suitable for visualizing the roots, canals, and the complete pulp chamber and apex were included in the study. Vertucci and Ahmed et al. classification systems were employed to determine the root canal morphology. 500 CBCT images and 3000 teeth were analyzed. Type I (1MA1) was the most frequent, followed by Type III (1MA1-2-1). 3.8% of teeth could not be classified with Vertucci system. In canine teeth, Vertucci type III (1MA1-2-1) was significantly more prevalent in males than females (p = 0.038) and Type I (1MA1) was less frequent in individuals aged 41-50 (p < 0.05). Canal divergence/merging was the most common at the middle/apical level for central (15.5%) and lateral (10.3%) teeth, and at the coronal/middle level for canine teeth (1.9%). Bilateral similarity was high for all tooth groups (> 78%). One-third of mandibular incisor teeth have two canals, with a significant number exhibiting canal divergence/merging that was separated in the middle region and merged in the apical region. The Vertucci classification was found to be inadequate in some cases, while Ahmed et al. classification was able to classify all mandibular incisors with a single code. Ahmed et al. classification is a more useful system for classifying all MA.

Automatic deep learning detection of overhanging restorations in bitewing radiographs.

OBJECTIVES: This study aimed to assess the effectiveness of deep convolutional neural network (CNN) algorithms for the detecting and segmentation of overhanging dental restorations in bitewing radiographs. METHODS: A total of 1160 anonymized bitewing radiographs were used to progress the artificial intelligence (AI) system for the detection and segmentation of overhanging restorations. The data were then divided into three groups: 80% for training (930 images, 2399 labels), 10% for validation (115 images, 273 labels), and 10% for testing (115 images, 306 labels). A CNN model known as You Only Look Once (YOLOv5) was trained to detect overhanging restorations in bitewing radiographs. After utilizing the remaining 115 radiographs to evaluate the efficacy of the proposed CNN model, the accuracy, sensitivity, precision, F1 score, and area under the receiver operating characteristic curve (AUC) were computed. RESULTS: The model demonstrated a precision of 90.9%, a sensitivity of 85.3%, and an F1 score of 88.0%. Furthermore, the model achieved an AUC of 0.859 on the receiver operating characteristic (ROC) curve. The mean average precision (mAP) at an intersection over a union (IoU) threshold of 0.5 was notably high at 0.87. CONCLUSIONS: The findings suggest that deep CNN algorithms are highly effective in the detection and diagnosis of overhanging dental restorations in bitewing radiographs. The high levels of precision, sensitivity, and F1 score, along with the significant AUC and mAP values, underscore the potential of these advanced deep learning techniques in revolutionizing dental diagnostic procedures.

Different modulation of STING/TBK1/IRF3 signaling by advanced glycation end products.

Advanced glycation end products (AGEs) are a heterogeneous group of compounds that are non-enzymatically produced by reactions between carbonyl compounds and proteins. Many types of AGEs are produced according to the type or concentration of the reacting carbonyl compound. We have previously demonstrated that a glycolaldehyde-derived AGE suppresses stimulator of interferon gene (STING)/TANK-binding kinase 1 (TBK1)/interferon regulatory transcription factor 3 (IRF3), which is a component of the innate immune system. In this report, we investigated the effects of AGEs prepared by several carbonyl compounds on STING/TBK1/IRF3 signaling. AGEs used in the present study were numbered based on the carbonyl compound type: AGE1, derived from glucose; AGE2, derived from glyceraldehyde; AGE3, derived from glycolaldehyde; AGE4, derived from methylglyoxal; and AGE5, derived from glyoxal. AGEs derived from aldehyde (AGE2 and AGE3) and dicarbonyl compounds (AGE4 and AGE5) suppressed cyclic GMP-AMP (cGAMP)-induced activation of STING/TBK1/IRF3 signaling, with different suppression efficiencies observed. Lysine modification by carbonyl compounds was related to the efficiency of the suppressive effect on STING/TBK1/IRF3 signaling. Among the AGEs used, only AGE1 enhanced cGAMP-induced activation of STING/TBK1/IRF3 signaling. Enhancing the modulation of STING/TBK1/IRF3 signaling by AGE1 was mediated by toll-like receptor 4. These results indicated that modulation of STING/TBK1/IRF3 signaling by prepared AGEs is dependent on the type and concentration of the carbonyl compound present. Modulating STING/TBK1/IRF3 signaling by AGEs may involve modification of lysine residues in proteins.

Histamine promotes angiogenesis through a histamine H1 receptor-PKC-VEGF-mediated pathway in human endothelial cells.

Histamine is a well-known inflammatory mediator, but how histamine induces angiogenesis remains poorly understood. In the present study, we demonstrated a dose-dependent dynamic tube formation in the human endothelial cell line EA.hy926 in the presence of histamine that was completely blocked by histamine H1 receptor (H1R) and protein kinase C (PKC) inhibitors. However, histamine H2, H3, and H4 receptor inhibitors did not inhibit tube formation, suggesting that H1R-PKC signaling is involved in histamine-induced tube formation. Moreover, we found an H1-specific induction of vascular endothelial growth factor (VEGF) expression. Inhibition of VEGF receptor 2 (VEGFR2) suppressed the histamine-induced tube formation, indicating that VEGF is downstream of histamine signaling. Additionally, we demonstrated that histamine stimulation induces the expression of critical regulators of angiogenesis such as matrix metalloproteinase (MMP)-9 and MMP-14 metalloproteases, as histamine-induced tube formation is blocked by MMP inhibitors. In summary, our study indicates that histamine can activate the H1R in human endothelial cells and thereby promote tube formation through the PKC, MMP, and VEGF signaling pathways.

Glycolaldehyde-derived advanced glycation end products promote macrophage proliferation via the JAK-STAT signaling pathway.

BACKGROUND: Advanced glycation end products (AGEs) are heterogeneous proinflammatory molecules produced by a non-enzymatic glycation reaction between reducing sugars (and their metabolites) and biomolecules with amino groups, such as proteins. Although increases in and the accumulation of AGEs have been implicated in the onset and exacerbation of lifestyle- or age-related diseases, including diabetes, their physiological functions have not yet been elucidated in detail. METHODS AND RESULTS: The present study investigated the cellular responses of the macrophage cell line RAW264.7 stimulated by glycolaldehyde-derived AGEs (Glycol-AGEs) known as representative toxic AGEs. The results obtained showed that Glycol-AGEs significantly promoted the proliferation of RAW264.7 cells at a low concentration range (1-10 µg/mL) in a concentration-dependent manner. On the other hand, neither TNF-α production nor cytotoxicity were induced by the same concentrations of Glycol-AGEs. The increases observed in cell proliferation by low concentrations of Glycol-AGEs were also detected in receptor triple knockout (RAGE-TLR4-TLR2 KO) cells as well as in wild-type cells. Increases in cell proliferation were not affected by various kinase inhibitors, including MAP kinase inhibitors, but were significantly suppressed by JAK2 and STAT5 inhibitors. In addition, the expression of some cell cycle-related genes was up-regulated by the stimulation with Glycol-AGEs. CONCLUSIONS: These results suggest a novel physiological role for AGEs in the promotion of cell proliferation via the JAK-STAT pathway.

Attitude and practice of regenerative endodontic procedures among endodontists and paediatric dentists: A multinational survey from 13 countries.

BACKGROUND: Regenerative endodontics (RET) refers to biologically based procedures that aim to restore damaged tooth structures and reinstate the pulp-dentine complex to its normal physiological state. AIM: The purpose of this study was to examine the attitudes and practices of endodontists and paediatric dentists regarding RET. DESIGN: A survey was conducted among endodontists and paediatric dentists from 13 countries. A number of factors were evaluated, including frequency of RET application, followed guidelines, disinfection techniques, intracanal medication type, scaffold type, preferred coronal seal material, and follow-up period. RESULTS: Among the 1394 respondents, 853 (61.2%) and 541 (38.8%) were endodontists and paediatric dentists, respectively. Almost half (43%) of participants have not performed RET yet. The American Association of Endodontics guideline (47.3%) was selected as the primary source for the clinical protocol. The most frequently selected irrigant solution was 1.5%-3% NaOCl at the first (26.1%) and second (13.6%) sessions. A blood clot (68.7%) and MTA (61.9%) were the most frequently selected scaffold type and coronal barrier. Most participants preferred a 6-month follow-up period. CONCLUSION: According to this survey, deviations exist from current RET guidelines regarding all aspects evaluated. Standardizing clinical protocols and adhering to available guidelines would help to ensure more predictable outcomes.

Caries-related salivary parameters and oral microbial flora in patients with type 1 diabetes: A meta-analysis.

OBJECTIVES: This study aimed to conduct a meta-analysis by synthesising the outcomes of studies that investigated the relationship between type 1 diabetes (T1D) and salivary flow rate (SFR), salivary pH (SpH), salivary buffer capacity (SBC), streptococcus Mutans (SM), and lactobacillus (LB) counts. MATERIAL AND METHODS: The PRISMA statement guide was followed for the meta-analysis. Electronic databases were searched, and study selection and data collection processes were performed. The risks of bias in individual studies and across studies were assessed. Mean differences (MD) and Odds Ratio (OR) were used to measure the effect estimates in the comparisons. RESULTS: 29 studies were included in the qualitative and quantitative syntheses. Significantly higher SFR (MD = -0.22, CI: -0.26, -0.18; p < 0.001) and SpH (MD = -0.59, CI: -0.81, -0.36; p < 0.001) were observed in the healthy individuals than T1D individuals. No significant difference was observed among groups in terms of SBC (MD = 0.10, CI: -0.46,0.66; p = 0.73). An increased odds ratio of SM counts were observed regarding the T1D (OR = 3.09, 95% CI: 1.16, 8.20; p = 0.02). No association was found between LB counts and T1D (OR = 2.15, 95% CI: 0.38, 11.98; p = 0.38). CONCLUSIONS: Subjects with T1D have a significantly lesser SFR and SpH than healthy individuals. But no significant difference is available in terms of SBC. Lower SM counts were observed in individuals with T1D, while no association was observed regarding LB counts. The tendency to dental caries is more likely in subjects with T1D due to lower SFR, SpH, and higher SM.

Identification of ribosomal protein L9 as a novel regulator of proinflammatory damage-associated molecular pattern molecules.

BACKGROUND: We previously reported that advanced glycation endproducts (AGEs) increase the proinflammatory activity of high mobility group box-1 (HMGB1), a representative damage-associated molecular pattern molecule (DAMP), through their direct interaction. This suggested that AGEs activate other DAMPs and led us to search for novel DAMPs capable of interacting with AGEs. METHODS AND RESULTS: The chromatographic analysis using AGE-immobilized gel revealed the ribosomal protein family to be a factor with binding activity to AGEs. Ribosomal protein L9 (RPL9), a member of the ribosomal protein family, was found in the centrifugal supernatant of ruptured cells and in the serum of lipopolysaccharide (LPS)-stimulated sepsis model mice, exhibiting similar characteristic properties to HMGB1. Although HMGB1 potentiated LPS-stimulated TNF-α expression in macrophage-like RAW264.7 cells, RPL9 hardly exhibited this activity. Of note, RPL9 significantly suppressed the potentiated mRNA expression and protein production of TNF-α by HMGB1 plus LPS stimulation, suggesting its regulatory roles in DAMP-induced proinflammatory activity. Based on the differential scanning fluorimetric analysis, the direct interaction between RPL9 and HMGB1 may play a role in the suppressive effects of RPL9. CONCLUSIONS: This study suggested that RPL9 is a novel type of DAMP with a regulatory role in the proinflammatory response and provided insight into the pathophysiology of inflammatory diseases.

Nordihydroguaiaretic acid inhibits glyoxalase I, and causes the accumulation of methylglyoxal followed by cell-growth inhibition.

BACKGROUND: Methylglyoxal (MGO) is a known toxic byproduct of glycolysis, with MGO-induced cytotoxicity believed to contribute to the pathogenesis of several diseases. Glyoxalase I (GLO1) is a key enzyme for eliminating MGO in mammalian cells, therefore, compounds affecting GLO1 activity are potential therapeutic agents for MGO-induced disorders. Previously, we found nordihydroguaiaretic acid (NDGA) as a potent GLO1 inhibitor. METHODS: The inhibitory characteristics of NDGA were determined spectrophotometrically with recombinant GLO1. NDGA-induced growth-inhibition and accumulation of MGO-derived advanced glycation end products (AGEs) were examined in EA.hy926 cells. RESULTS: NDGA showed significant inhibition of GLO1 enzymatic activity in a dose-dependent manner. Its Ki value was estimated to be 146-fold lower than that of myricetin, a known GLO1 inhibitor. The co-addition of MGO with NDGA to the cells resulted in significant growth inhibition, suggesting that MGO accumulation, sufficient to affect cell growth, was caused by NDGA inhibiting GLO1. These findings were supported by the observations that the addition of aminoguanidine, a typical MGO scavenger, significantly reversed cell-growth inhibition by co-addition of MGO with NDGA, and that an increase in intracellular MGO-derived AGEs was observed during incubation with the co-addition of MGO with NDGA. CONCLUSION: NDGA was found to be a novel and potent inhibitor of GLO1. The co-addition of NDGA with MGO to the cells resulted in increased intracellular MGO accumulation followed by enhanced cell-growth inhibition.

Association between asthma and caries-related salivary factors: a meta-analysis.

OBJECTIVES: This meta-analysis aimed to examine the comprehensive conclusive evidence of association between asthma and caries-related salivary factors including salivary pH (SpH), salivary flow rate (SFR), salivary buffer capacity (SBC), and other salivary components. METHODS: Electronic databases (Web of Science, PubMed, Scopus, Cochrane Library, and Open Gray databases) were searched for relevant studies. After screening, studies were selected and data were collected from each study. The risk of bias in individual studies and across studies was evaluated. Mean differences (MD) were used to measure the effect estimates in the comparisons of SFR, SpH, SBC, and other salivary components. Additional analyses, namely sensitivity, subgroup, and Grades of Recommendation, Assessment, Development, and Evaluation analyses, were also conducted. RESULTS: Eighteen and fourteen studies were included in the qualitative and quantitative synthesis, respectively. Significantly higher SFR (MD = -0.3, 95% CI [-0.39, -0.2], p < 0.001) and SpH (MD = -0.25, 95% CI [-0.45, -0.05], p = 0.01) were found in the reference group compared to the group with asthma. A significant difference in SBC was found only for unstimulated saliva (MD = -0.20, 95% CI [-0.24, -0.15], p < 0.001). No significant associations were found between asthma and other salivary components (p > 0.05). CONCLUSIONS: Notwithstanding the limitations of this study, the evidence showed that SFR whether stimulated or unstimulated was significantly reduced in asthma patients. SBC and SpH were significantly reduced in asthma patients only when saliva was unstimulated. No evidence was found regarding the association between asthma and other salivary components.

Involvement of multiple scavenger receptors in advanced glycation end product-induced vessel tube formation in endothelial cells.

Toxic advanced glycation end products (toxic AGEs) derived from glycolaldehyde (AGE3) have been implicated in the development of diabetic vascular complications such as retinopathy characterised by excessive angiogenesis. Different receptor types, such as receptor for AGEs (RAGE), Toll like receptor-4 and scavenger receptors, are expressed in endothelial cells and contribute to AGE-elicited alteration of cell function. In the present study, we examined the involvement of AGE-related receptors on AGE-induced angiogenesis in endothelial cells. The effects of pharmacological inhibitors or receptor neutralizing antibodies on AGE3-induced tube formation were investigated using the in vitro Matrigel tube formation assay in b.End5 cells (mouse endothelial cells). AGE3-induced signalling pathways and receptor expression changes were analysed by Western blot analysis and flow cytometry, respectively. Both FPS-ZM1, a RAGE inhibitor, and fucoidan, a ligand for scavenger receptors, suppressed AGE3-induced tube formation. Cocktails of neutralizing antibodies against the scavenger receptors CD36, CD163 and LOX-1 prevented AGE3-induced tube formation. AGE3 activated mTOR signalling, resulting in facilitation of tube formation. Activation of the AGE-RAGE pathway also led to the upregulation of scavenger receptors. Taken together, our findings suggest that the scavenger receptors CD36, CD163 and LOX-1 in conjunction with the RAGE receptor work together to mediate toxic AGE-induced facilitation of angiogenesis.

Potential of a Novel Chemical Compound Targeting Matrix Metalloprotease-13 for Early Osteoarthritis: An In Vitro Study.

Osteoarthritis is a progressive disease characterized by cartilage destruction in the joints. Matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTSs) play key roles in osteoarthritis progression. In this study, we screened a chemical compound library to identify new drug candidates that target MMP and ADAMTS using a cytokine-stimulated OUMS-27 chondrosarcoma cells. By screening PCR-based mRNA expression, we selected 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide as a potential candidate. We found that 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide attenuated IL-1ß-induced MMP13 mRNA expression in a dose-dependent manner, without causing serious cytotoxicity. Signaling pathway analysis revealed that 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide attenuated ERK- and p-38-phosphorylation as well as JNK phosphorylation. We then examined the additive effect of 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide in combination with low-dose betamethasone on IL-1ß-stimulated cells. Combined treatment with 2-(8-methoxy-2-methyl-4-oxoquinolin-1(4H)-yl)-N-(3-methoxyphenyl) acetamide and betamethasone significantly attenuated MMP13 and ADAMTS9 mRNA expression. In conclusion, we identified a potential compound of interest that may help attenuate matrix-degrading enzymes in the early osteoarthritis-affected joints.

NF-Ä¸ß upregulates ADAMTS5 expression by direct binding after TNF-α treatment in OUMS-27 chondrosarcoma cell line.

Inflammation caused-aggrecan degradation is a critical event in the pathogenesis of osteoarthritis (OA). The aggrecanases like a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5) are assumed to be key players in the aggrecan destruction. To develop the comprehensive therapy method for OA, it is essential to elucidate the activation mechanism of ADAMTS5 gene after stimulation of inflammatory cytokines like tumor necrosis factor-α (TNF-α). The cell lines of human chondrosarcoma (OUMS-27) and embryonic kidney (HEK293T) were incubated with tumor necrosis factor-α (TNF-α) for certain time periods, and the expression level of ADAMTS5 was measured in both mRNA and protein levels. Tissue-specific ADAMTS5 activation was founded to be induced after TNF-α treatment. Then, the constructs for the promoter region of ADAMTS5 were prepared and luciferase assay was conducted to understand the involvement mechanism of nuclear factor-kappa beta (NF-ĸß) in ADAMTS5 activation. It was demonstrated that NF-Ä¸ß induces the ADAMTS5 expression level by directly binding the promoter region of ADAMTS5. Although the TNF-α blocker is used for OA treatment, the development of a more comprehensive treatment strategy is an urgent need. Our experimental data contributes in terms of selecting NF-Ä¸ß as a target molecule. Up to date, NF-Ä¸ß has been proven to involve in the ADAMTS5 up-regulation after several pro-inflammatory cytokines stimulation. In conclusion, our findings make important contributions to the knowledge about the roles of NF-Ä¸ß in ADAMTS5 activation under inflammatory conditions. So, NF-Ä¸ß could be considered to be a potential target for OA treatment.

Mechanical strain attenuates cytokine-induced ADAMTS9 expression via transient receptor potential vanilloid type 1.

The synovial fluids of patients with osteoarthritis (OA) contain elevated levels of inflammatory cytokines, which induce the expression of a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) and of the matrix metalloproteinase (MMP) in chondrocytes. Mechanical strain has varying effects on organisms depending on the strength, cycle, and duration of the stressor; however, it is unclear under inflammatory stimulation how mechanical strain act on. Here, we show that mechanical strain attenuates inflammatory cytokine-induced expression of matrix-degrading enzymes. Cyclic tensile strain (CTS), as a mechanical stressor, attenuated interleukin (IL)-1ß and tumor necrosis factor (TNF)-α-induced mRNA expression of ADAMTS4, ADAMTS9, and MMP-13 in normal chondrocytes (NHAC-kn) and in a chondrocytic cell line (OUMS-27). This effect was abolished by treating cells with mechano-gated channel inhibitors, such as gadolinium, transient receptor potential (TRP) family inhibitor, ruthenium red, and with pharmacological and small interfering RNA-mediated TRPV1 inhibition. Furthermore, nuclear factor κB (NF-κB) translocation from the cytoplasm to the nucleus resulting from cytokine stimulation was also abolished by CTS. These findings suggest that mechanosensors such as the TRPV protein are potential therapeutic targets in treating OA.

Induction of CEMIP in Chondrocytes by Inflammatory Cytokines: Underlying Mechanisms and Potential Involvement in Osteoarthritis.

In patients with osteoarthritis (OA), there is a decrease in both the concentration and molecular size of hyaluronan (HA) in the synovial fluid and cartilage. Cell migration-inducing hyaluronidase 1 (CEMIP), also known as hyaluronan (HA)-binding protein involved in HA depolymerization (HYBID), was recently reported as an HA depolymerization-related molecule expressed in the cartilage of patients with OA. However, the underlying mechanism of CEMIP regulation is not well understood. We found that CEMIP expression was transiently increased by interleukine-1ß (IL-1ß) stimulation in chondrocytic cells. We also observed that ERK activation and NF-κB nuclear translocation were involved in the induction of CEMIP by IL-1ß. In addition, both administration of HA and mechanical strain attenuated the CEMIP induction in IL-1ß-stimulated chondrocytes. In conclusion, we clarified the regulatory mechanism of CEMIP in chondrocytes by inflammatory cytokines and suggested the potential involvement in osteoarthritis development.

Functional analysis of ESM1 by siRNA knockdown in primary and metastatic head and neck cancer cells.

BACKGROUND: Genetic factors play a large role in cancer, and thus, there is a great desire to understand the effects of different genes in cancer and to also develop gene therapy for better treatments. Therefore, the development of alternative diagnosis and therapy modalities is of utmost importance. The aim of our study was to illuminate the role of ESM1 (endothelial cell-specific molecule-1, also known as Endocan) in proliferation and migration of head and neck cancer, thus helping to pave the way for new treatment modalities and predictive biomarkers. METHODS: ESM1 expression was shown with immunofluorescence assay using confocal laser scanning microscope in primary and metastatic head and neck cancer cells. ESM1 expression was knocked down by RNA interference in head and neck cancer cells. Knockdown efficiency was evaluated by quantitative real-time RT-PCR and Western blot. Cell proliferation and migration assays were performed by xCELLigence real-time cell analysis system. RESULTS: Immunofluorescence assay showed nuclear localization and high expression of ESM1 in primary and metastatic head and neck cancer cells. ESM1 mRNA and protein levels were significantly decreased in ESM1-knockdown cells compared to control. ESM1-knockdown cells showed reduced proliferation and migration activity when compared to control cells. CONCLUSION: These findings suggest that ESM1 has roles on proliferation and migration of head and neck cancer cells.

Host-produced ADAMTS4 Inhibits Early-Stage Tumor Growth.

Several research groups demonstrated that 'a disintegrin-like and metalloproteinase with thrombospondin type 1 motifs (ADAMTS)'-family proteases play roles in cancer progression. However, the origins and contributions of these proteases are not known. Here, we demonstrate an association between host-produced ADAMTS4 and early-stage tumor growth. Murine Lewis lung carcinoma (LLC) tumors showed marked expressions of Adamts4 and Adamts5. We examined the contributions and distributions of host-derived Adamts4 and Adamts5 on tumor growth, using Adamts4LacZ/LacZ and Adamts5LacZ/LacZ knockout mice. Interestingly, the Adamts4LacZ/LacZ mice showed enhanced tumor growth compared to wild-type mice at 5-, 10- and 12-days post-inoculation, whereas the Adamts5LacZ/LacZ mice did not show significant differences in tumor growth. We next examined LacZ distribution in LLC tumor-bearing Adamts4LacZ/LacZ mice by ß-galactosidase (ß-gal) staining. We found that the ß-gal-positive signals were strictly localized at the interior areas of the tumor at 10 days post-inoculation. Multiple staining demonstrated that most of the ß-gal-positive cells were localized at the tumor vasculature in Adamts4LacZ/LacZ mice. Interestingly, ß-gal-positive signals were not co-localized with biglycan after 10 days post-inoculation, excluding the biglycan cleavage by host-derived ADAMTS4. Taken together, these findings illustrate that host-derived ADAMTS4 was expressed at the tumor vessels and was associated with early-stage tumor growth.

Leptin induces ADAMTS-4, ADAMTS-5, and ADAMTS-9 genes expression by mitogen-activated protein kinases and NF-ĸB signaling pathways in human chondrocytes.

Elucidation of the causes of inflammation has vital importance in the development of new approaches for the treatment of arthritic diseases. The degradation of aggrecan by upregulated disintegrin and metalloproteinase with trombospondin motifs (ADAMTSs) is the key event in the development of both rheumatoid arthritis (RA) and osteoarthritis (OA). Increased levels of leptin in both RA and OA have been demonstrated, thus linking leptin to arthritic diseases, but the mechanism has not been clarified. This study investigated the putative role of signaling pathways (p38, JNK, MEK1, NF-ĸB, and PI3) involved in leptin-induced cartilage destruction. Normal human articular chondrocytes were cultured with recombinant human leptin at 100, 250, 500, and 1000 ng/mL doses for 6, 12, 24, and 48 h, after which ADAMTS-4, -5, and -9 genes expression were determined by real time-polymerase chain reaction (RT-PCR) and Western Blot methods. The signaling pathways involved in leptin-induced ADAMTSs upregulation were also investigated by using inhibitors of signaling pathways. It was demonstrated that ADAMTSs expression level was peaked at 1000 ng/mL doses for 48 hours, and MAPKs (p38, JNK, and MEK) and NF-ĸB signaling pathways involving in leptin triggered ADAMTSs upregulation. Obesity as a risk for RA and OA may contribute to the inflammation of both RA and OA diseases by secreting adipokines like leptin. We hypothesize that leptin is involved in the development of RA and OA accompanied with obesity by increasing ADAMTS-4, -5, and -9 genes expression via MAPKs and NF-ĸB signaling pathways.

ADAMTS1 inhibits lymphangiogenesis by attenuating phosphorylation of the lymphatic endothelial cell-specific VEGF receptor.

Angiogenesis and lymphangiogenesis play roles in malignant tumor progression, dissemination, and metastasis. ADAMTS1, a member of the matrix metalloproteinase family, is known to inhibit angiogenesis. Recombinant ADAMTS1 was shown to strongly inhibit angiogenesis. We investigated whether ADAMTS1 inhibited lymphangiogenesis in the present study. We examined cell proliferation and cell migration in normal human dermal lymphatic microvascular endothelial cells (HMVEC-dLy) transduced with or without adenoviral human ADAMTS1 gene therapy. We then examined the VEGFC/VEGFR3 signal transduction pathway in ADAMTS1-transduced HMVEC-dLy. Cell proliferation and tube formation in Matrigel were significantly lower with transduced ADAMTS1 than with control (non-transduced HMVEC-dLy). The phosphorylation of VEGFR3 was also attenuated by ADAMTS1 gene therapy in HMVEC-dLy. Immunoprecipitation assays revealed that ADAMTS1 formed a complex with VEGFC. Our results demonstrated that ADAMTS1 inhibited lymphangiogenesis in vitro. The data highlight the new function of ADAMTS1 in the regulation of lymphangiogenesis and the therapeutic potential of ADAMTS1 in cancer therapy.