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Aims: Type 2 diabetes is a rising problem and a significant risk factor for small and large vessel disease. The present study aims to investigate the effect of a 6-week aerobic exercise program on High-mobility Group Box 1 (HMGB1) gene expression in aortic tissue of diabetic rats. Methods & Materials: In this experimental study, 40 male rats aged 8 weeks were randomly selected. Once familiarized with the exercise protocol, they were divided into four groups of healthy-control (n=10), diabetic-control (n=10), healthy-exercise (n=10), and diabetic-exercise (n=10). Type 2 diabetes was first induced, and then the rats run on a treadmill for 6 weeks, 5 sessions per week. After 12-14 h of fasting and 72 h after the last session, aortic tissue sampling was performed for HMGB1 analysis by quantitative real-time polymerase chain reaction (q-RT PCR) technique. Data analysis was performed using 1-way ANOVA and Tukey post hoc test at the significant level of P

Aims: Type 2 diabetes is a rising problem and a significant risk factor for small and large vessel disease. The present study aims to investigate the effect of a 6-week aerobic exercise program on High-mobility Group Box 1 (HMGB1) gene expression in aortic tissue of diabetic rats. Methods & Materials: In this experimental study, 40 male rats aged 8 weeks were randomly selected. Once familiarized with the exercise protocol, they were divided into four groups of healthy-control (n=10), diabetic-control (n=10), healthy-exercise (n=10), and diabetic-exercise (n=10). Type 2 diabetes was first induced, and then the rats run on a treadmill for 6 weeks, 5 sessions per week. After 12-14 h of fasting and 72 h after the last session, aortic tissue sampling was performed for HMGB1 analysis by quantitative real-time polymerase chain reaction (q-RT PCR) technique. Data analysis was performed using 1-way ANOVA and Tukey post hoc test at the significant level of P

Background: High-mobility group box 1 (HMGB1) protein plays an important pathogenic role in various diseases such as pulmonary fibrosis. However, the relationship between variation of HMGB1 gene an...

The estimation of accurate post mortem interval (PMI) is a crucial question in forensic medicine. Several approaches have been used to determine the PMI including physical, metabolic, autolytic, entomological, physiochemical and biochemical methods over time. For estimation of PMI, RNA degradation after death is reported to be an important tool. This study aimed to analyse the pattern of gene expression by serial estimation of cardiac specific cardiac troponin I (cTnI) gene and autophagy gene HMGB1 for determining PMI at room temperature by using housekeeping gene GAPDH. Right ventricular heart tissue weighing 10 g was collected and harvested from 17 medico-legal autopsies. The tissue was homogenized in phosphate-buffered saline (PBS) on ice. Further, homogenate of cardiac tissue was analysed by quantitative Real time polymerase chain reaction (qRtPCR) for gene amplification and gene expression of cTnI, HMGB1 gene and GAPDH, at different time intervals (0,6,12 hours) at room temperature. The result revealed ∆Ct value of cTnI gene of the cardiac muscle showing almost equal degradation at equal time interval correlated with PMI within 0 to 12 hours at room temperature, and the ∆Ct value of HMGB1 degraded to half in every subsequent 6-hour interval at room temperature. In conclusion, the estimation of PMI by analysis of serial estimation of gene expression is a decent new tool in forensic medicine. The study shows an equal degradation of cTnI gene at equal time interval and HMGB1 degrades to half at six-hour interval. Therefore, these can be useful for estimation for PMI.

To explore the potential role of HMGB1 on TDI-induced NLRP3 inflammasome activation, HBE cells were treated with TDI-HSA conjugate to observe the changes of HMGB1, TLR4, NF-κB, Nrf2 and NLRP3 inflammasome related proteins expressions, ROS release and MMP. NAC, TPCA-1 and Resatorvid pre-treatments were applied to explore the effects of ROS, NF-κB and TLR4 on TDI-induced NLRP3 inflammasome activation. The CRISPR/Cas9 system was used to construct HMGB1 gene knockout HBE cell line and then to explore the role of HMGB1 on TDI-HSA induced NLRP3 inflammasome activation. GL pre-treatment was applied to further confirm the role of HMGB1. Results showed that TDI increased HMGB1, TLR4, P-p65, Nrf2 proteins expressions and ROS release, decreased MMP level and activated NLRP3 inflammasome in HBE cells in a dose dependent manner. NAC, TPCA-1 and Resatorvid pre-treatments decreased the expression of P-p65 and inhibited NLRP3 inflammasome activation. Inhibition of HMGB1 decreased Nrf2 expression and ROS release, improved MMP level and reduced NLRP3 inflammasome activation. GL ameliorated NLRP3 inflammasome activation via inhibiting HMGB1 regulated ROS/NF-κB pathway. These results indicated that HMGB1 was involved in TDI-induced NLRP3 inflammasome activation as a positive regulatory mechanism. The study provided a potential target for early prevention and treatment of TDI-OA.

Dysregulation of inflammatory cytokines in keratinocytes promote the pathogenesis of the skin inflammation, such as allergic contact dermatitis (ACD). High-mobility group box 1 protein (HMGB1) has been implicated in the promotion of skin inflammation upon its extracellular release as a damage-associated molecular pattern molecule. However, whether and how HMGB1 in keratinocytes contributes to ACD and other skin disorders remain elusive. In this study, we generated conditional knockout mice in which the Hmgb1 gene is specifically deleted in keratinocytes, and examined its role in ACD models. Interestingly, the mutant mice showed exacerbated skin inflammation, accompanied by increased ear thickening in 2,4-dinitrofluorobenezene-induced ACDs. The mRNA expression of interleukin-24 (IL-24), a cytokine known to critically contribute to ACD pathogenesis, was elevated in skin lesions of the mutant mice. As with constitutively expressed, IL-4-induced Il24 mRNA, expression was also augmented in the Hmgb1-deficient keratinocytes, which would account for the exacerbation of ACD in the mutant mice. Mechanistically, we observed an increased binding of trimethyl histone H3 (lys4) (H3K4me3), a hallmark of transcriptionally active genes, to the promoter region of the Il24 gene in the hmgb1-deficient cells. Thus, the nuclear HMGB1 is a critical "gate keeper" in that the dermal homeostasis is contingent to its function in chromatin remodeling. Our study revealed a facet of nuclear HMGB1, namely its antiinflammatory function in keratinocytes for the skin homeostasis.

Background Non-coding small RNAs are involved in organism development, and their aberrant regulation induces various diseases, including hepatocellular carcinoma (HCC), but their exact mechanisms have not been determined. Objective The aim was to investigate the role of miR-142-3p on HMGB1 expression in hepatocellular carcinoma. Methods Expression levels of miR-142-3p in HCC tissues and cultured cells were measured by RT-PCR. The invasion and metastasis abilities of HepG2 cells according to Transwell migration and invasion assays, and protein expression was measured by western blotting. Results The present study reported that miR-142-3p promotes the invasion and migration of HCC cells. miR-142-3p levels are lower in HCC tissues than in adjacent non-cancerous tissues, suggesting a tumor suppressor role for miR-142-3p. Highmobility group box protein 1 (HMGB1) is an oncogene that promotes the metastasis of HCC. miR-142-3p or HMGB1 knockdown alone inhibits the invasion and migration of HCC cells, and HMGB1 overexpression impedes the effect of miR-142-3p. Further studies showed that HMGB1 is a direct target gene of miR-142-3p in HCC. miR-142-3p represses HMGB1 gene transcription by directly binding to the 3' untranslated region (UTR) of HMGB1, thereby inhibiting cancer cell invasion and migration. Conclusion This study, for the first time, reports that miR-142-3p is a novel tumor suppressor that inhibits the invasion and migration of HCC cells by directly regulating gene transcription of HMGB1. Thus, miR-142-3p may be a potential diagnostic and therapeutic biomarker for HCC patients.

// Chiao-Wen Lin 1, 2 , Ying-Erh Chou 3, 4 , Chia-Ming Yeh 4, 5 , Shun-Fa Yang 4, 5 , Chun-Yi Chuang 3, 6 and Yu-Fan Liu 7, 8 1 Institute of Oral Sciences, Chung Shan Medical University, Taichung, Taiwan 2 Department of Dentistry, Chung Shan Medical University Hospital, Taichung, Taiwan 3 School of Medicine, Chung Shan Medical University, Taichung, Taiwan 4 Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan 5 Institute of Medicine, Chung Shan Medical University, Taichung, Taiwan 6 Department of Otolaryngology, Chung Shan Medical University Hospital, Taichung, Taiwan 7 Department of Biomedical Sciences, College of Medicine Sciences and Technology, Chung Shan Medical University, Taichung, Taiwan 8 Division of Allergy, Department of Pediatrics, Chung Shan Medical University Hospital, Taichung, Taiwan Correspondence to: Yu-Fan Liu, email: yfliu@csmu.edu.tw Keywords: HMGB1, polymorphism, OSCC, bioinformatics analysis, haplotypes Received: January 04, 2017 Accepted: February 15, 2017 Published: March 11, 2017 ABSTRACT Oral squamous cell carcinoma (OSCC) is a common malignancy that has been causally associated with both hereditary and acquired factors. The high mobility group box 1 ( HMGB1 ) gene plays an important role as a DNA chaperone to help maintain nuclear homeostasis. Altered expression of HMGB1 has been implicated in a wide range of pathological processes, including inflammation and cancer. The present study explores the impact of HMGB1 gene polymorphisms, combined with environmental risks regarding susceptibility to oral tumorigenesis. Four single-nucleotide polymorphisms (SNPs) of the HMGB1 gene, rs1412125, rs2249825, rs1045411, and rs1360485, were evaluated in 1,200 normal controls and 772 patients with OSCC. We found an association between the wild-type allele of rs1045411 and genotypes CT and CT/TT (AOR=0.754, 95% CI=0.582-0.978 and AOR=0.778, 95% CI=0.609-0.995, respectively). Additionally, bioinformatics analysis was used to characterize the functional relevance of these variants for the miRNA-505-5p binding site and transcriptional regulation by the HMGB1 3’-UTR and promoter regions. Moreover, in considering behavioral exposure to environmental carcinogens, the presence of the four HMGB1 SNPs, combined with/without betel quid chewing and smoking showed, profoundly synergistic effects on the risk of OSCC. In conclusion, we present a potential clinical relevance for HMGB1 variants in OSCC, as well as associations between HMGB1 polymorphisms, haplotypes and environmental risk factors. The finding may help in development of optimal therapeutic approaches for OSCC patients.

BACKGROUND High-mobility group box 1 (HMGB1) plays a crucial role in a variety of diseases, including neonatal necrotizing enterocolitis (NEC). The purpose of this study was to investigate the association of HMGB1 gene single-nucleotide polymorphisms (SNPs) with susceptibility and survival prognosis in Chinese Han neonates with NEC. MATERIAL AND METHODS The HMGB1 gene rs1360485, rs1045411, and rs2249825 site SNPs were genotyped in all participants. The mRNA expression of serum HMGB1 was examined using quantitative reverse transcription-polymerase chain reaction. The correlation of the HMGB1 rs1360485 SNP with NEC neonatal survival prognosis was evaluated by univariate analysis and logistic multivariate regression analysis. RESULTS The TC and CC genotype and C allele distribution frequencies of the rs1360485 SNP were lower in the NEC group, and the differences were statistically significant (all P0.05). Individuals carrying the TC and CC genotype or C allele had a low risk of being affected by NEC. However, the genotype and allele distributions of rs1045411 and rs2249825 were not significantly different between the patient and control groups (P0.05). NEC neonates with HMGB1 gene rs1360485 site mutations had lower mRNA levels of serum HMGB1 than those with rs1360485 site wild-type, and the rs1360485 genotypes TC and CC could independently predict better survival outcomes in NEC neonates. CONCLUSIONS This study demonstrated that the rs1360485 SNP of the HMGB1 gene is associated with susceptibility of NEC in neonates, and the rs1360485 genotypes TC and CC may affect HMGB1 expression and are associated with the survival prognosis of neonates with NEC.

AIMS High mobility group box 1 (HMGB1) is a chromatin structural protein, expressed ubiquitously in the nuclei of mammalian cells. When transported extracellularly, it acts as a tumour suppressor and oncogenic protein. In malignant pleural mesothelioma (MPM), high serum levels of HMGB1 have been related to a poor prognosis. Conversely, the significance of HMGB1 expression in MPM tissues is still unclear. METHODS AND RESULTS Biopsy samples from 170 patients with MPM were assessed by immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) to evaluate HMGB1 protein and gene expression. The expression level of HMGB1 protein was scored using a semiquantitative system that sums the intensity (0-3) and the percentage (from 0 to 4) of positively stained cells in nuclei, cytoplasm and in both. The final score was considered as high (>3) or low (

Chromatin is the template for the basic processes of replication and transcription, making the maintenance of chromosomal integrity critical for cell viability. To elucidate how dividing cells respond to alterations in chromatin structure, here we analyse the replication programme of primary cells with altered chromatin configuration caused by the genetic ablation of the HMGB1 gene, or three histone H1 genes. We find that loss of chromatin compaction in H1-depleted cells triggers the accumulation of stalled forks and DNA damage as a consequence of transcription-replication conflicts. In contrast, reductions in nucleosome occupancy due to the lack of HMGB1 cause faster fork progression without impacting the initiation landscape or fork stability. Thus, perturbations in chromatin integrity elicit a range of responses in the dynamics of DNA replication and transcription, with different consequences on replicative stress. These findings have broad implications for our understanding of how defects in chromatin structure contribute to genomic instability., Spanish Ministry of Economy and Competitiveness, MINECO (BFU2013-45276-P and BFU2016-78849-P, co-financed by The European Union FEDER funds) to M.G., and by ANR grant (ANR-14-CE10-0008-02) and Ligue Contre le Cancer Comité de Paris (RS16/75-108) to J.-C.C., R.A. and J.M.F.-J. were supported by grants from the Portuguese Foundation for Science and Technology (SFRH/BD/81027/11) and MINECO FPI (BES-2014-070050)

High-mobility group box 1 (HMGB1) was first described as an architectural chromatin-binding protein. Today, a wealth of evidence indicates that this protein is very versatile and serves an amazing assortment of roles in the nucleus, cytoplasm and extracellular milieu. As a result, HMGB1 is fast becoming recognized as a key regulator of protective and pathological immune responses. Whilst acknowledging the many functions of HMGB1 and its family members, we focus this review on their role as broad effectors of immune responses mediated by nucleic acids. In addition, we touch upon the recent progress in determining the in vivo role of HMGB1 as revealed by the study of mice conditionally null for the Hmgb1 gene.

The study was carried out to investigate changes in gene expression of innate antibacterial signaling pathways in patients with pancreatic cancer. Expression of the following genes was measured in peripheral blood leukocytes of 55 patients with pancreatic adenocarcinoma using real-time polymerase chain reaction (RT-PCR): TLR4, NOD1, MyD88, TRAF6 and HMGB1. The levels of expression of TLR4, NOD1 and TRAF6 genes were significantly elevated (p = 0.007; p = 0.001 and p = 0.01, respectively), while MyD88 expression was markedly reduced (p = 0.0002), as compared to controls. Expression of TLR4 and NOD1 exceeded the normal level more than 3.5-fold and there was a significant correlation found between the expression of these genes (r = 0.558, p < 0.001). TLR4, NOD1 and MyD88 genes were expressed at a similar level both before and after surgery. No significant changes in the expression of HMGB1 gene were observed. The results of the study clearly indicate abnormal expression of genes belonging to innate antibacterial signaling pathways in peripheral blood leukocytes of patients with pancreatic cancer, which may lead to leukocyte dysfunction. Overexpression of TLR4, NOD1 and TRAF6 genes, and decreased MyD88 gene expression may contribute to chronic inflammation and tumor progression by up-regulation of the innate antibacterial response. The parameters tested are useful for monitoring innate immunity gene disorders and pancreatic cancer progression.

High-mobility group box 1 (HMGB1), a highly conserved DNA-binding protein, is involved in nucleosome formation and transcriptional regulation, and can also act as an extracellular cytokine to trigger inflammation and immune responses. In this study, we identified a HMGB1 gene (hereafter designated as CgHMGB1) in the Pacific oyster Crassostrea gigas. The full-length CgHMGB1 cDNA is 833 bp including 5' and 3'-untranslated regions (UTRs) of 145 and 79 bp, respectively, and an open reading frame (ORF) of 609 bp. The gene encodes a 202 amino acid polypeptide with an estimated molecular mass of 23.3 kDa. Sequence alignment shows that CgHMGB1 contains two basic HMG boxes and a highly acidic C-terminal domain. Recombinant CgHMGB1 proteins can enhance the mRNA level of various inflammatory cytokines in vivo. Typically, CgHMGB1 is localized in the nucleus, though lipopolysaccharide can induce its release to cytoplasm. Moreover, luciferase reporter assays reveal that CgHMGB1 cannot stimulate Nuclear Factor-kappa B reporter activity alone, but it can enhance Rel-dependent NF-kappa B activation in a dose-dependent manner. CgHMGB1 is highly expressed in hemocytes and its transcripts are significantly more abundant following bacterial challenge. Our results suggest that CgHMGB1 plays an essential role in innate defense by enhancing Rel-activated NF-kappa B activity and inducing the expression of inflammatory cytokines. (c) 2013 Elsevier Ltd. All rights reserved.

High mobility group box 1 protein is primarily a nuclear protein that acts as an architectural transcription factor to facilitate transcription, replication, recombination, repair, nucleosome remod...

High-mobility group box 1 protein (HMGB1) is a nuclear DNA-binding protein, which also functions as a pleiotropic cytokine, implicated in the pathology of several different immune-mediated diseases. The purpose of this study was to examine the HMGB1 gene for putative polymorphisms in 103 healthy Caucasian Danish blood donors. A total of six polymorphisms and four mutations were identified in the HMGB1 gene. Subsequent MatInspector estimation revealed that several polymorphisms might have a potential regulatory impact on HMGB1 transcription. This study has characterized genetic variations in the HMGB1 gene locus, which may have a regulating role in the expression of HMGB1, providing the basis for molecular investigations of the HMGB1 gene in different disease settings.

The high mobility group box 1 protein has been identified as a key player in chromatin homeostasis including transcription regulation, recombination, repair, and chromatin remodeling. Emerging findings indicate HMGB1 protein over expression in nearly all types of human cancers and inflammatory disorders. Thus it is considered as a potential therapeutic target for treating various malignancies. We screened the promoter region of hmgb1 gene and selected a positive regulatory element of 25 base pair duplex (25RY) (-165 to -183) as a potential target for chemotherapeutic intervention. The molecular interaction of actinomycin (ACT) with the regulatory region of hmgb1 gene was characterized by spectroscopic, calorimetric and molecular docking studies. The hypochromic and bathochromic shift in the absorption spectrum, stabilization of 25RY duplex against thermal denaturation, perturbation of CD spectrum of duplex and enhancement of fluorescence intensity of actinomycin indicate strong binding of actinomycin to the hmgb1 promoter region (25RY).The energetics was characterized to be endothermic and entropy driven. All these results are in good agreement with in silico investigation that suggest minor groove binding with effective intercalation at GC bases of actinomycin to 25RY. This study identifies hmgb1 gene promoter region a potential target for the anticancer therapautiucs.

Metastasis is one of the major problems when dealing with malignant neoplasias. Accordingly, the finding of molecular targets, which can be addressed to reduce tumour metastasising, will have significant impact on the development of new therapeutic approaches. Recently, the receptor for advanced glycation end products (RAGE)–high mobility group B1 (HMGB1) protein complex has been shown to have significant influence on invasiveness, growth and motility of tumour cells, which are essential characteristics required for metastatic behaviour. A set of in vitro and in vivo approaches showed that blocking of this complex resulted in drastic suppression of tumour cell growth. Due to the similarities of human and canine cancer the dog has joined the common rodent animal model for therapeutic and preclinical studies. However, complete characterisation of the protein complex is a precondition to a therapeutic approach based on the blocking of the RAGE–HMGB1 complex to spontaneously occurring tumours in dogs. We recently characterised the canine HMGB1 gene and protein completely. Here we present the complete characterisation of the canine RAGE gene including its 1384 bp mRNA, the 1215 bp protein coding sequence, the 2835 bp genomic structure, chromosomal localisation, gene expression pattern, and its 404 amino acid protein. Furthermore we compared the CDS of six different canine breeds and screened them for single nucleotide polymorphisms.

High mobility group box protein 1 (HMGB1) has been considered as a ubiquitous nuclear protein with an architectural function, but even early reports have described its presence outside of the nucleus. Today, we have only started to understand the extranuclear and extracellular functions of HMGB1: we know that it participates in developmental and differentiation processes, triggers and modulates many of the inflammatory cascades in the body, and may even be involved in the metastatic invasion programme of cancer cells. Given such diverse roles, it is important to know which cells express HMGB1, where, and how much. The present review deals with the expression pattern of HMGB1 and provides evidence that, far from being housekeeping, the HMGB1 gene is tightly regulated. This can have implications for therapeutic intervention on inflammatory diseases as well as cancer.

Due to the close similarities of numerous canine diseases to their human counterparts, the dog could join the mouse as the species of choice to unravel the genetic background of complex diseases as e.g. cancer and metabolic diseases. Accordingly, the role of the dog as a model for therapeutic approaches is strongly increasing. However, prerequisite for such studies is the characterization of the corresponding canine genes. Recently, the human high mobility group protein B1 (HMGB1) has attracted considerable interest of oncologists because of what is called its “double life”. Besides its function as an architectural transcription factor HMGB1 can also be secreted by certain cells and then acts as a ligand for the receptor for advanced glycation end products (RAGE). The binding of HMGB1 to RAGE can activate key cell signaling pathways, such as p38MAPK, JNK, and p42/p44MAPK emphasizing the important role of HMGB1 in inflammation and tumor metastasis. These results make HMGB1 a very interesting target for therapeutic studies done in model organisms like the dog. In this study we characterized the molecular structure of the canine HMGB1 gene on genomic and cDNA levels, its predicted protein, the gene locus and a basic expression pattern.

The highly conserved, ubiquitous high mobility group protein HMGB1 (formerly named as HMG1) is an architectural transcription factor encoded by a single functional gene in human. HMGB1 is expressed in almost all cell or tissue types studied. In general, it is expressed at a basal level in most cells but at a slightly elevated level of 2--3-fold in actively proliferating tissues or estrogen stimulated breast cancer cells. To understand the regulatory mechanism controlling expression of the human HMGB1 gene, we cloned and analyzed the upstream region as well as the first intron of this gene. We found that transcription of the human HMGB1 gene in the breast cancer MCF-7 cells starts at one major site 57 nucleotides upstream from the first exon-intron boundary. Expression of the human HMGB1 gene is under the control of a very strong TATA-less promoter, which has an activity more than 18-fold that of the SV40 promoter. Immediately upstream, a silencer element is present. This silencer can repress the activity of the HMGB1 promoter down to just one-sixth. The first intron of the human HMGB1 gene contains enhancer elements, which can increase the human HMGB1 promoter activity by 2--3-fold. We postulate that the human HMGB1 gene is capable of being expressed at a very high level. The basal level of expression observed in most cells is probably a result of the strong promoter being held in check by the silencer. The 2--3-fold increase in HMGB1 expression observed in proliferating cells or breast cancer cells stimulated by estrogen may probably result from the action of the enhancer elements in intron 1.