No abstract available.
HMGB1 Protein* ; Pemphigus*

Humans ; Asthma/diagnosis* ; HMGB1 Protein

HMGB1 is a widely existing DNA-binding nuclear protein, participating in gene transcription, damage repair, recombination and stabilizing nucleosome construction. Under injury, infection and chemotherapy, HMGB1 can be released by nature immunocyte and necrosis cells as a DAMP, exerting pleiotropic biological effects by binding to RAGE, TLR and CXCL12, which lead to activation of CDC42, mitogen-activated protein kinases (MAPKs), c-IAP and NF-κB, thereby promoting angiogenesis, unlimited replicative potential, tissue invasion and metastasis. And it also involves in immune response by regulating immunocyte function as a immunocyte warning signal. Scholars have detected that HMGB1 is over expressed and released following chemotherapy and radiation therapy in cells of hematological malignancies, promoting malignant cell replication, decreasing therapeutic effect. Recently, endogenous HMGB1 has been implied to be an intrinsic modulator of autophagy and referenced to resistant to apoptosis in malignant hematosis cells. In contrast, through suppression of HMGB1 expression, tumor cell apoptosis and chemotherapeutic drug sensitivity were increased, which will be a new strategy for the treatment of hematological malignancies. In this article, the basic characteristics of HMGB1, including structure and biological features, and HMGB1 and tumors such as lymphoma, myeloproliferative neoplasms and acute myeloid leukemia are reviewed.
Animals ; HMGB1 Protein ; Hematologic Neoplasms ; therapy ; Humans

Endotoxemia ; metabolism ; pathology ; HMGB1 Protein ; Humans ; Liver ; metabolism ; pathology

High mobility group box-1 protein (HMGB1), which is a nuclear protein, participates in chromatin architecture and transcriptional regulation. When released from cells, HMGB1 also plays a well-established role as a pro-inflammatory mediator during innate immune responses to injury. In the initial stage of injury, there is a release of large quantities of early pro-inflammatory mediators to initiate or perpetuate immune responses against pathogens, but this pro-inflammatory period is transient, and it is followed by a prolonged period of immune suppression. At present, several lines of evidences have suggested that HMGB1 is a late cytokine provoking delayed endotoxin morbidity, which may enhance the production of early proinflammatory mediators, and it can contribute potently to the activation of different immune cells and play a role in the development of host cell-mediated immunity. The biology of HMGB1 has been extensively studied as a pro-inflammatory cytokine of systemic inflammation, however, this review will attempt to provide a summary of the effects of HMGB1 on different immune cells and its regulatory mechanism in acute insults.
Cytokines ; immunology ; HMGB1 Protein ; immunology ; Humans ; Immunity, Cellular ; Inflammation ; immunology

OBJECTIVETo investigate the effect of decreased expression of high mobility group Box-1 on the proliferation and apoptosis of HepG2 cells.

METHODSThree specific siRNAs of HMGB1 were designed and synthesized, and were transiently transfected into HepG2 cells by Lipofectamine 2000. The HMGB1 expression in HepG2 cells was detected by RT-PCR and Western blotting respectively. The proliferation activity in vitro was assessed by MTT assay. In situ apoptosis was evaluated by terminal deoxynucleotidyl transferase-deoxyuridine triphosphate nick end labeling (TUNEL) assay.

RESULTSAll of these specific HMGB1-siRNAs (1, 2, 3) efficiently and specifically inhibited the expression of the HMGB1 gene, and the levels of HMGB1 mRNA were 1.147+/-0.024, 1.014+/-0.042, 0.435+/-0.055, respectively, in HMGB1-siRNAs transfection group, which were significantly lower than that in Lipofectamine 2000 alone group (1.411+/-0.065, P < 0.01). Correspondingly, all of these specific HMGB1-siRNAs (1, 2, 3) could efficiently and specifically inhibit the expression of the HMGB1 protein, and the levels of HMGB1 protein were 0.369+/-0.035, 0.340+/-0.028, 0.097+/-0.020, respectively, in HMGB1-siRNAs transfection group, which were significantly lower than that in Lipofectamine 2000 alone group (0.553+/-0.051, P < 0.01). Of the 3 specific HMGB1-siRNAs, HMGB1-siRNA-3 (siRNAH3) had the highest inhibition rate (80%). The proliferation of HepG2 cells was markedly inhibited by siRNAH3 transfection. Compared to mock-transfection, siRNAH3 transfection dramatically suppressed the proliferation of HepG2 cells (P < 0.01). Moreover, siRNAH3 can induce apoptosis (P < 0.01).

CONCLUSIONsiRNA targeting HMGB1 mRNA can specifically reduce HMGB1 gene and protein expression. siRNAH3 can effectively suppress the proliferation and induce apoptosis of HepG2 cells.

Apoptosis ; Cell Proliferation ; HMGB1 Protein ; genetics ; Hep G2 Cells ; Humans ; RNA, Small Interfering

Atrial fibrillation (AF) is the most common sustained dysrhythmia in clinical practice. The bulk of evidence suggests that inflammatory processes, oxidative stress and matrix metalloproteinase are associated with development of AF. However, these agents may be involved in high mobility group box 1 protein (HMGB1). We hypothesized that HMGB1 may be a possible pathogenic link to AF. A growing body of evidence supports these hypotheses. First, the level of serum HMGB1 is significantly increased in patients with AF including paroxysmal and persistent AF. Second, HMGB1 has been identified as a new pro-inflammatory cytokine in cardiovascular diseases, along with tumor necrosis factor (TNF)-α, interleukin (IL)-6, and C-reactive protein, and there is cross-talk between HMGB1 and inflammatory cytokines. Third, oxidative stress is involved in the release of the pro-inflammatory cytokine, HMGB1, indicating there is cross-talk between oxidative stress and inflammation, and oxidative stress may reinforce the effect of inflammation on the pathogenesis of AF and inflammation may play a more important role in the pathogenesis of AF. Fourth, HMGB1 can promote matrix metalloproteinase-9 upregulation and activation. Fifth, HMGB1 receptors (receptor for advanced glycation end products, Toll-like receptor-2,4) may mediate the atrial structural remodeling or be up-regulated in patients with non-valvular AF. These results suggest that HMGB1 may participate in the pathogenesis of AF and provide a potential target for pharmacological interruption of AF.
Atrial Fibrillation ; metabolism ; HMGB1 Protein ; metabolism ; Humans ; Metalloendopeptidases ; metabolism ; Oxidative Stress ; physiology

This study was aimed to establish a stable subline of K562 cells (K562-HMGB1) overexpressing HMGB1 protein and K562-HMGB1 sublines served as control, so as to provide a basis for exploring the role of hmgb1 gene in occurrence and development of leukemia and their mechanism. Protein-coding gene of hmgb1 was amplified by PCR with cDNA as template, which was synthesized by reverse transcription from total RNA extracted from U937 cells. The PCR-amplified hmgb1 gene was ligated into PMD18-T vector (PMD18-T-HMGB1 vector), and then transformed into E. coli strain DH5α. DH5α containing PMD18-T-HMGB1 vector were grown on LB agar plate supplemented with 100 µg/ml ampicillin overnight. The single ampicillin-selected DH5α clone was picked for culturing overnight and then harvested for plasmid extraction. The extracted plasmid was characterized to contain hmgb1 gene digested with the desired restriction enzymes of KpnI/XhoI. The correctness of hmgb1 sequence was confirmed with DNA sequencing. The insert of hmgb1 gene contained in PMD18-T-HMGB1 vector was cut out with restriction enzymes of KpnI/XhoI and then ligated into eukaryotic expression vector pcDNA3.1 to form pcDNA3.1-HMGB1 vector. 10µg of pcDNA3.1-HMGB1 or pcDNA3.1 plasmid was separately electroporated into K562 cells. At 48 hours after electroporation the cells were cultured with G418 at a final concentration of 800 µg/ml for over 2 weeks. Finally stably transfected sublines of K562 cells containing hmgb1 gene (K562-HMGB1), and of K562 containing pcDNA3.1 vector (K562-pcDNA3.1) served as a control, were obtained. The transcriptional or translational expression of hmgb1 gene was detected with RT-PCR or Western blot, respectively, to testify transfected efficiency and validity of stable subline of K562-HMGB1. The results indicated that the eukaryotic expression vector pcDNA3.1-HMGB1 plasmid was successfully constructed and was electroporated into K562 cells. The transcriptional or translational expression of hmgb1 gene in the stable subline of K562 cells containing hmgb1 gene was overexpressed. It indicated that stable subline of K562-HMGB1 cells was successfully established. It is concluded that the stable sublines of K562-HMGB1 cells or K562-pcDNA3.1 cells are successfully established, which provides a basis for exploring the roles and mechanisms of hmgb1 gene in leukemogenesis and development of leukemia.
Gene Expression ; Genes, Regulator ; Genetic Vectors ; HMGB1 Protein ; genetics ; Humans ; K562 Cells ; metabolism ; Plasmids ; Transformation, Genetic

Animals ; Endotoxins ; Female ; HMGB1 Protein ; biosynthesis ; Liver Failure, Acute ; chemically induced ; metabolism ; Male ; Rats ; Rats, Wistar

OBJECTIVETo study the association between serum level of high-mobility group box 1(HMGB1) and neonatal respiratory distress syndrome (NRDS).

METHODSA total of 35 infants with NRDS and 35 normal neonates (control group) were enrolled. Peripheral venous blood samples were collected with 12-24 hours after birth. ELISA was used to measure the serum level of HMGB1.

RESULTSThe infants with mild and severe NRDS had a significantly higher serum level of HMGB1 than the control group (P<0.05). The infants with severe NRDS had a significantly higher serum level of HMGB1 than those with mild NRDS (P<0.05). The infants with NRDS who died had a significantly higher serum level of HMGB1 than those who survived (P<0.05). The receiver operating characteristic (ROC) curve showed that the optimal cut-off value for serum level of HMGB1 to predict NRDS was 625.3 pg/mL with an area under the ROC curve (AUC) of 0.846 (95%CI: 0.755-0.936), and the optimal cut-off value for serum level of HMGB1 to predict the death of infants with NRDS was 772.2 pg/mL with an AUC of 0.916 (95%CI: 0.813-1.000).

CONCLUSIONSInfants with NRDS have a significant increase in the serum level of HMGB1, and the serum level of HMGB1 can well predict the development and prognosis of NRDS.

Female ; HMGB1 Protein ; blood ; Humans ; Infant, Newborn ; Male ; Prognosis ; Respiratory Distress Syndrome, Newborn ; blood ; diagnosis