Serum high mobility group box protein 1 as a clinical marker for ovarian cancer

HMGB2-induced calreticulin translocation required for immunogenic cell death and ferroptosis of cancer cells are controlled by the nuclear exporter XPO1

Cisplatin and oxaliplatin cause the secretion of high mobility group box 1 (HMGB1) protein from cancer cells, which is necessary for initiation of immunogenic cell death (ICD). Calreticulin (CRT) translocation from the endoplasmic reticulum to the plasma membrane is also required; oxaliplatin induces this translocation but cisplatin does not. We have discovered that oxaliplatin causes the secretion of both HMGB1 and HMGB2 from the cell nucleus into the extracellular milieu. We previously showed that cisplatin-mediated secretion of HMGB1 is controlled by the nuclear exporter XPO1 (chromosomal maintenance 1; CRM1). We now find that XPO1 regulates oxaliplatin-mediated secretion of both HMGB1 and HMGB2. XPO1 inhibition causes nuclear accumulation of both proteins, inhibition of oxaliplatin-mediated ferroptosis of colon cancer cells, and inhibition of CRT translocation to the plasma membrane of lung and colon cancer cells. Incubation of cancer cells with cell targeted (CT)-HMGB2 confirmed that HMGB2 is required for the CRT translocation. Furthermore, CT-HMGB2 is three orders of magnitude more potent at inducing CRT translocation than oxaliplatin.

HMGB1 enhances the migratory and invasive abilities of A2780/DDP cells by facilitating epithelial to mesenchymal transition via GSK‑3β

The aim of the present study was to investigate the impact and mechanism of high mobility group box 1 (HMGB1) on the regulation of cell migration and invasion in A2780/DDP cisplatin-resistant ovarian cancer cells. After transfecting small interfering (si)RNA-HMGB1 into A2780/DDP cells, Transwell migration and invasion assays were conducted to assess alterations in the cell migratory and invasive abilities. Additionally, western blotting analyses were performed to examine changes in HMGB1, phosphorylated (p)-GSK-3β, GSK-3β, E-cadherin and vimentin expression levels. The results of the present study demonstrated that the migratory and invasive abilities of A2780/DDP cells were significantly higher compared with those of A2780 cells. Additionally, the expression levels of HMGB1, p-GSK-3β and the mesenchymal phenotype marker, vimentin, in A2780/DDP cells were significantly elevated relative to the levels in A2780 cells. Conversely, the expression level of the epithelial phenotype marker, E-cadherin, was markedly decreased compared with that in A2780 cells. Following transfection of A2780/DDP cells with siRNA-HMGB1, there was a significant reduction in the rate of cell migration and invasion. Simultaneously, the expression levels of HMGB1, p-GSK-3β and vimentin were downregulated while the level of E-cadherin was upregulated. It was therefore concluded that the high expression of HMGB1 in A2780/DDP cells enhanced the cell migration and invasion abilities by facilitating epithelial to mesenchymal transition via GSK-3β.

Immunogenic Biomarkers HMGB1 and sRAGE Are Potential Diagnostic Tools for Ovarian Malignancies

BACKGROUND

High mobility group box 1 (HMGB1), soluble receptor of advanced glycation end products (sRAGE) and programmed cell death markers PD-1 and PD-L1 are immunogenic serum biomarkers that may serve as novel diagnostic tools for cancer diagnosis.

METHODS

We investigated the four markers in sera of 231 women, among them 76 with ovarian cancer, 87 with benign diseases and 68 healthy controls, using enzyme immunoassays. Discrimination between groups was calculated using receiver operating characteristic (ROC) curves and sensitivities at fixed 90% and 95% specificities.

RESULTS

HMGB1 levels were significantly elevated and sRAGE levels were decreased in cancer patients as compared to benign and healthy controls. In consequence, the ratio of HMGB1 and sRAGE discriminated best between diagnostic groups. The areas under the curve (AUCs) of the ROC curves for differentiation of cancer vs. healthy were 0.77 for HMGB1, 0.65 for sRAGE and 0.78 for the HMGB1/sRAGE ratio, and slightly lower for the differentiation of cancer vs. benigns with 0.72 for HMGB1, 0.61 for sRAGE and 0.74 for the ratio of both. The highest sensitivities for cancer detection at 90% specificity versus benign diseases were achieved using HMGB1 with 41.3% and the HMGB1/sRAGE ratio with 39.2%, followed by sRAGE with 18.9%. PD-1 showed only minor and PD-L1 no power for discrimination between ovarian cancer and benign diseases.

CONCLUSION

HMGB1 and sRAGE have differential diagnostic potential for ovarian cancer detection and warrant inclusion in further validation studies.

The role of the inflammasome and its related pathways in ovarian cancer

Ovarian cancer (OC) is the most lethal tumor of the female reproductive tract and one of the most prevalent causes of death among female cancer patients. The absence of suitable procedures for early diagnosis, chemoresistance, and limited surgical debulking are all contributing to poor survival in patients. Despite aggressive treatments, the majority of patients have a recurrence within 16-22 months. Inflammasomes are multimeric protein complexes that play a major role in the innate immune system and inflammation. The overexpression of inflammasome-related pathways, including NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3), Absent in melanoma 2 (AIM2), caspase-1, and Interleukin (IL)-1 have been reported in OC patients and in vitro cell lines. Therefore, inflammasome-related genes and protein might have a role in OC pathogenesis. Considering the potential relationship between inflammasome and OC, this study aimed to provide a literature-based review to explain the role of inflammasome and inflammation in cancer progression in OC.

Astragaloside IV antagonizes M2 phenotype macrophage polarization-evoked ovarian cancer cell malignant progression by suppressing the HMGB1-TLR4 axis

Macrophages are the most abundant cells in tumor stroma and their polarization within tumor microenvironment exert the key roles in tumorigenesis. Astragaloside IV is a natural extract from traditional Chinese herbal Radix Astragali, and fulfills pleiotropic function in several cancers. Nevertheless, its function in ovarian cancer microenvironment remains elusive. In the present research, astragaloside IV exhibited little cytotoxicity within a certain dose range in THP-1 cells. Moreover, astragaloside IV suppressed the ratio of CD14⁺CD206⁺ cells in IL-4/IL-13-treated THP-1 macrophages and transcripts of M2 macrophage markers (including CD206, CCL24, PPARγ, Arg-1, IL-10), indicating the inhibitory effects of astragaloside IV on IL-4/IL-13-induced macrophage M2 polarization. Intriguingly, astragaloside IV antagonized M2 macrophages coculture-evoked cell proliferation, invasion and migration in ovarian cancer cells. During this process, administration with astragaloside IV restrained the high expression of high-mobility group box1 (HMGB1) and TLR4 in macrophages co-cultured with ovarian cancer cells, concomitant with decreases in release of M2 marker TGF-β, MMP-9 and IL-10. Moreover, targeting the HMGB1 signaling reversed M2 macrophages-induced ovarian cancer cell proliferation, invasion and migration. Noticeably, exogenous HMGB1 overturned the inhibitory efficacy of astragaloside IV against macrophage M2 polarization-evoked malignant potential in ovarian cancer cells. Together, these findings suggest that astragaloside IV may protect against M2 macrophages-evoked malignancy in ovarian cancer cells by suppressing the HMGB1-TLR4 signaling. Therefore, astragaloside may alleviate the progression of ovarian cancer by regulating macrophage M2 polarization within tumor microenvironment, implying a promising therapeutic strategy against ovarian cancer.

The HMGB1-2 Ovarian Cancer Interactome. The Role of HMGB Proteins and Their Interacting Partners MIEN1 and NOP53 in Ovary Cancer and Drug-Response

High mobility group box B (HMGB) proteins are overexpressed in different types of cancers such as epithelial ovarian cancers (EOC). We have determined the first interactome of HMGB1 and HMGB2 in epithelial ovarian cancer (the EOC-HMGB interactome). Libraries from the SKOV-3 cell line and a primary transitional cell carcinoma (TCC) ovarian tumor were tested by the Yeast Two Hybrid (Y2H) approach. The interactome reveals proteins that are related to cancer hallmarks and their expression is altered in EOC. Moreover, some of these proteins have been associated to survival and prognosis of patients. The interaction of MIEN1 and NOP53 with HMGB2 has been validated by co-immunoprecipitation in SKOV-3 and PEO1 cell lines. SKOV-3 cells were treated with different anti-tumoral drugs to evaluate changes in HMGB1, HMGB2, MIEN1 and NOP53 gene expression. Results show that combined treatment of paclitaxel and carboplatin induces a stronger down-regulation of these genes in comparison to individual treatments. Individual treatment with paclitaxel or olaparib up-regulates NOP53, which is expressed at lower levels in EOC than in non-cancerous cells. On the other hand, bevacizumab diminishes the expression of HMGB2 and NOP53. This study also shows that silencing of these genes affects cell-viability after drug exposure. HMGB1 silencing causes loss of response to paclitaxel, whereas silencing of HMGB2 slightly increases sensitivity to olaparib. Silencing of either HMGB1 or HMGB2 increases sensitivity to carboplatin. Lastly, a moderate loss of response to bevacizumab is observed when NOP53 is silenced.

MiR-34c acts as a tumor suppressor in non-small cell lung cancer by inducing endoplasmic reticulum stress through targeting HMGB1

Objective

To investigate the role of miR-34c in lung cancer.

Methods

The levels of microRNA-34c (miR-34c) expression in non-small cell lung cancer (NSCLC) tissue and cell lines were examined by the qRT-PCR assay. High mobility group box 1 (HMGB1) expression in NSCLC was assessed by immunohistochemical analysis (IHC), qRT-PCR, and Western blot assays. The effects of miR-34c overexpression or HMGB1 knockdown on cell proliferation and apoptosis were evaluated by CCK-8 and flow cytometry analysis, respectively. Cellular reactive oxygen species (ROS) production in NSCLC cells was detected using a ROS kit. The levels of Bax, p-ERK, eIF2α, GADD153, and IRE1α expression in treated NSCLC cells were measured by Western blot assays. In addition, the interaction between miR-34c and HMGB1 was verified by the dual-luciferase reporter assay.

Results

miR-34c was only slightly expressed, while HMGB1 was highly expressed in NSCLC tissues and cell lines. Overexpression of miR-34c or knockdown of HMGB1 inhibited cell proliferation, promoted cell apoptosis, and induced ER stress in NSCLC cells. In terms of mechanism, miR-34c negatively regulated HMGB1 expression by directly targeting the 3ʹ-untranslated region (UTR) of HMGB1 mRNA. In addition, we proved that HMGB1 overexpression could block the effects of miR-34c on NSCLC cell proliferation, apoptosis, and ER stress.

Conclusion

miR-34c may suppress NSCLC tumors by targeting HMGB1 mRNA, promoting endoplasmic reticulum stress, and increasing ROS levels. Our findings suggest that miR-34c has a role in NSCLC.

Overexpression of high mobility group box 1 (HMGB1) has no correlation with the prognosis in glioma

Aim: We aimed to characterize the role of HMGB1 overexpression in glioma and to evaluate its use as a biomarker. Materials & methods: We used the gene expression datasets and tissue microarray to assess the expression levels of HMGB1 among gliomas of all grades; We then assessed its correlation with the malignancy and outcome of glioma. Results: The increase in HMGB1 mRNA and protein levels was found in glioma, but there was no correlation between HMGB1 expression and glioma malignancy, and overall survival and vital status of glioma patients. Conclusion: Overexpression of HMGB1 is not associated with the malignancy and outcome in glioma. And it is not the valuable biomarker for the early diagnosis of glioma.

The molecular mechanisms of Aloin induce gastric cancer cells apoptosis by targeting High Mobility Group Box 1

Purpose: Aloin (ALO), a bioactive ingredient extracted from aloe vera, has anti-tumor effects. High Mobility Group Box 1 (HMGB1), a highly conserved nuclear DNA-binding protein, has been implicated in various cancer types. Highly expressed HMGB1 is closely associated with tumor cells apoptosis, proliferation and migration. We investigated the specific molecular mechanisms by which ALO-induced apoptosis by targeting HMGB1 in gastric cancer cells.

Materials and methods: Human gastric cancer HGC-27 cells were treated with different doses of ALO (100, 200 and 400 µg/ml) for 24 h, after which DAPI staining was used to observe the nuclear morphology, Annexin V/PI double staining assay was used to determine the rate of apoptosis; Western blotting was used to detect the levels of PARP, pro-caspase3, HMGB1 and RAGE; nuclear translocation of HMGB1 was determined by conducting a nucleoplasm separation experiment. The Enzyme linked immunosorbent assay (ELISA) assay was used to detect release of HMGB1. The HGC-27 cells, transfected with HMGB1 shRNA plasmids, were stimulated with ALO for 24 h, after which a flow cytometry assay was used to detect the rate of apoptosis. HGC-27 cells were pre-treated with or without ALO and then stimulated with rhHMGB1, the phosphorylation of Akt, mTOR, P70S6K, S6, 4EBP1, ERK, P90RSK, cAMP regulatory element binding (CREB) were detected by Western blotting.

Results: After different doses of ALO treatment, the nuclei showed morphological changes characteristic of apoptosis. Apoptotic rates were enhanced in a dose dependent manner. The level of cleaved PARP was enhanced and pro-caspase3, HMGB1 and RAGE levels were reduced, HMGB1 nuclear translocation and release were inhibited. The activation of rhHMGB1-induced Akt-mTOR-P70S6K and ERK-CREB signalling pathways was inhibited by ALO. Blocking these signalling pathways by special inhibitors and HMGB1 knockdown could enhance ALO-induced HGC-27 cell apoptosis.

Conclusion: ALO- induced HGC-27 cell apoptosis by down-regulating expressions of HMGB1 and RAGE, inhibiting HMGB1 release and then suppressing rhHMGB1-induced activation of Akt-mTOR-P70S6K and ERK-P90RSK-CREB signalling pathways.

MiR-1284 enhances sensitivity of cervical cancer cells to cisplatin via downregulating HMGB1

BACKGROUND

Chemotherapy is one of the commonest therapeutic method for cervical cancer. There are some common chemotherapy drugs, such as cisplatin, docetaxel, paclitaxel and selenium nanoparticle. microRNAs (miRNAs) have been verified to be regulators in various human cancers. This study aims to investigate the effects of miR-1284 on the cisplatin sensitivity of cervical cancer cells.

METHODS

The levels of miR-1284 in different tissues and cell lines were detected through using qRT-PCR analysis. Kaplan Meier analysis was utilized to analyze the influence of miR-1284 expression on the overall survival rate of cervical cancer patients. The biological effects of miR-1284 on the progression and chemosensitivity of cervical cancer were tested through conducting functional assays. Mechanism investigations were used to prove the binding relation between miR-1284 and HMGB1. Rescue assays were applied to demonstrate the effects of miR-1284-HMGB1 axis on chemosensitivity of cervical cancer cells.

RESULTS

miR-1284 was down-expressed in cervical cancer tissues and cell lines. Patients with low level of miR-1284 had low overall survival rate. Upregulation of miR-1284 suppressed proliferation and invasion, while promoted apoptosis. Moreover, upregulated miR-1284 enhanced sensitivity of cervical cancer cells to cisplatin. HMGB1 was a target gene of miR-1284. HMGB1 reversed the effects of miR-1284 on the progression and chemosensitivity of cervical cancer cells.

CONCLUSION

miR-1284 enhances sensitivity of cervical cancer cells to cisplatin via targeting HMGB1.

Association between the HMGB1/TLR4 signaling pathway and the clinicopathological features of ovarian cancer

In the present study, the expression levels of high‑mobility group protein B1 (HMGB1), Toll‑like receptor 4 (TLR4), nuclear factor (NF)‑κB and tumor necrosis factor (TNF)‑α in malignant epithelial ovarian cancer (MEOC) were investigated in regards to several clinicopathological characteristics. A total of 20 patients with MEOC who underwent surgery were recruited in the present study. The mRNA and protein expression of HMGB1, TLR4, NF‑κB and TNF‑α was determined in patients with MEOC and compared with expression levels in 20 patients diagnosed with benign ovarian cysts (BOC). It was demonstrated that the mRNA and protein expression of HMGB1, TLR4, NF‑κB and TNF‑α in MEOC was significantly increased, compared with the BOC group (P<0.01). The gene and protein expression of HMGB1, TLR4, NF‑κB and TNF‑α was significantly increased in the advanced tumor stage and poorly differentiated group (P<0.01). The present study suggested that the HMGB1/TLR4 signaling pathway was overactive in MEOC, and was associated with MEOC tumor cell proliferation, invasion and metastasis. Furthermore, this may have been mediated via NF‑κB signaling.

High Mobility Group Box Protein 1 Serves as a Potential Prognostic Marker of Lung Cancer and Promotes Its Invasion and Metastasis by Matrix Metalloproteinase-2 in a Nuclear Factor-κB-Dependent Manner

Several studies have reported a significant role of high mobility group box protein 1 (HMGB1) in lung cancer. Nevertheless, there is a lack of knowledge regarding the expression of HMGB1 and its correlation with the clinicopathological features of lung cancer. In addition, the potential molecular mechanisms underlying the role of HMGB1 in lung cancer are still unknown. We therefore investigated the clinicopathological and prognostic significance as well as the potential role of HMGB1 in the development and progression of lung cancer. HMGB1 expression in the tumor tissues of the cohort correlated with clinicopathological features. Moreover, lung cell migration and invasion were significantly increased after treatment with HMGB1. The matrix metalloproteinase-2 (MMP-2) expression and activity were upregulated after treatment with HMGB1, while the upregulated expression of MMP-2 stimulated by HMGB1 in lung cancer cells was significantly reduced with the blockage of si-p65. These results indicated that HMGB1 expression was significantly associated with lung cancer progression. We also showed that HMGB1 promoted lung cancer invasion and metastasis by upregulating the expression and activity of MMP-2 in an NF-κB-dependent manner. Taken together, these data suggested that HMGB1 may be a potential prognosis and therapeutic marker for lung cancer.

The effect of HMGB1 on the clinicopathological and prognostic features of non-small cell lung cancer

Several studies have assessed the diagnostic and prognostic values of high mobility group protein box 1 (HMGB1) expression in non-small cell lung cancer (NSCLC), but these results remain controversial. The purpose of this study was to perform a meta-analysis of the gene microarray analyses of datasets from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) to evaluate the association of HMGB1 expression with the clinicopathological and prognostic features of patients with NSCLC. Furthermore, we investigated the underlying molecular mechanisms by bioinformatics analysis. Twenty relevant articles involving 2651 patients were included in this meta-analysis; the HMGB1 expression in NSCLC tissues was significantly higher than that in the healthy non-cancer control tissues. We also found an indication by microarray analysis and meta-analysis that HMGB1 expression was associated with the cancer TNM Staging System. In terms of prognostic features, a survival analysis from KM-Plotter tool revealed that the high HMGB1 expression group exhibited poorer survival in lung adenocarcinoma (ADC) and overall NSCLC patients. The survival and disease-free analyses from TCGA datasets also showed that HMGB1 mainly affected the development of patients with ADC. Therefore, we focused on how HMGB1 affected the prognosis and development of ADC using bioinformatics analyses and detected that the mitogen-activated protein kinases (MAPK), apoptosis and cell cycle signaling pathways were the key pathways that varied during HMGB1 up-regulation in ADC. Moreover, various genes such as PLCG2, the phosphatidylinositol-4, 5-bisphosphate 3-kinase superfamily (PI3Ks), protein kinase C (PKC) and DGKZ were selected as hub genes in the gene regulatory network. Our results indicated that HMGB1 is a potential biomarker to predict progression and survival of NSCLC, especially of ADC types.

Glycyrrhizin Suppresses the Growth of Human NSCLC Cell Line HCC827 by Downregulating HMGB1 Level

Lung cancer has very high mortality and glycyrrhizin was found to significantly inhibit the growth of lung cancer cells in vitro and tissues in mice. However, the detailed inhibitory role of glycyrrhizin in the growth of lung cancer is still unclear. In this study, we first found that glycyrrhizin inhibited the growth of lung tumor in PDX mice. And high level of HMGB1 promoted the migration and invasion of lung cancer cells, which was suppressed by glycyrrhizin. Moreover, glycyrrhizin reduced the activity of JAK/STAT signaling pathway, which is the upstream regulator of HMGB1. Therefore, this study revealed a potential mechanism by which glycyrrhizin can inhibit the progression of lung cancer.

The efficacy of gastrodin in combination with folate and vitamin B12 on patients with epilepsy after stroke and its effect on HMGB-1, IL-2 and IL-6 serum levels

This study evaluated the efficacy of gastrodin in combination with folate (FOL) and vitamin-B12 (V-B12) on patients with epilepsy after stroke (EAS) and its effect on high-mobility group protein B1 (HMGB-1), interleukin-1 (IL-1), and IL-6 serum levels. The clinical data of 92 EAS patients admitted for treatment between April, 2014 and March, 2016 were collected. These patients were randomly divided into control and observation groups (n=46 each) using computer software. Patients in the control group were administered only regular antiepileptic drugs, whereas observation group patients also received a combination of gastrodin, FOL and V-B12. After treatment, we compared efficacy, frequency of epileptic seizure, and Montreal cognitive assessment (MoCA) scores. Serum homocysteine (HCY), FOL and V-B12 levels were detected 3 months later. Enzyme-linked immunosorbent assay (ELISA) was used to detect changes in serum HMGB-1, IL-2 and IL-6 levels at one day before treatment and on the 7th, 21st, 30th and 90th days after treatment. Pearson's correlation coefficient was utilized to analyze the correlations of HMGB-1 with IL-2 and IL-6. The total treatment effectiveness rate was 95.65% in the observation group, which was significantly higher than the control group (73.91%, p<0.05). Epileptic seizure frequency and MoCA scores significantly improved in the observation group (p<0.05). Serum HCY levels were significantly lower, whereas FOL and V-B12 serum levels were significantly higher, at 3 months post-treatment start in the observation group relative to control group (p<0.05). After treatment, serum HMGB-1, IL-2 and IL-6 levels progressively decreased over time in both groups, but observation group levels were significantly lower than in control group (p<0.05). Pearson's correlation coefficient analysis showed that HMGB-1 levels were positively correlated with IL-2 and IL-6 levels. A combination of gastrodin, FOL and V-B12 for EAS can significantly improve inflammatory response symptoms, decrease HCY levels, and increase FOL and V-B12 levels in serum while effectively controlling epileptic seizures, thus exhibiting relatively better clinical efficacy. Therefore, this combination treatment is worthy of being promoted in clinical practice.

High mobility group protein B1 is a predictor of poor survival in ovarian cancer

High-mobility group protein B1 (HMGB1) has been implicated in numerous tumour types where expression regulates tumour cell growth and survival. We hypothesised that high HMGB1 expression in ovarian tumours would predict poor patient survival.

Using tissue microarrays of primary ovarian cancers combined with a comprehensive database of clinicopathological variables, the expression of HMGB1 was assessed by immunohistochemistry in two independent cohorts (n=194 and n=360) using a monoclonal antibody specific for HMGB1.

Kaplan-Meier analysis showed an association of HMGB1 expression with progression free survival in the primary cohort (p=0.023). In the validation cohort, expression was associated with overall survival (p=0.002). Low expression of HMGB1 was protective and in a multivariate model HMGB1 expression was shown to be an independent predictor of poor survival in ovarian cancer (p=0.006).

The role of HMGB1 in cancer is complex. As high levels of HMGB1 expression are likely to render ovarian cancer cells resistant to chemotherapy, therapies targeting the HMGB1 axis may be appropriate in the treatment of ovarian cancer patients.

MicroRNA-200c inhibits epithelial-mesenchymal transition, invasion, and migration of lung cancer by targeting HMGB1

MicroRNAs (miRs) play critical roles in cancer development, proliferation, epithelial-mesenchymal transition (EMT), invasion, and migration through regulating the expression of oncogenes and tumour suppressor genes. Previous studies have indicated that miR-200c acts as a tumour suppressor in various cancers by downregulating high-mobility group box 1 (HMGB1) and thereby suppressing EMT and metastasis. In addition, miR-200c was reported to be downregulated and correlated with poor outcomes in non-small cell lung cancer (NSCLC). However, its functional role in HMGB1 regulation in NSCLC is still unclear. This study aimed to clarify whether miR-200c acts as a tumour suppressor in NSCLC by downregulating HMGB1, which is associated with EMT, invasion, cytoskeleton rearrangement, and migration in vitro and in vivo. In order to demonstrate HMGB1 downregulation by miR-200c, the NSCLC cell line A549 was transfected with miR-200c mimic or inhibitor. The mimic significantly reduced HMGB1 expression and suppressed EMT, invasion, and migration, while the inhibitor generated the opposite effects. Additionally, using xenograft mouse models, we confirmed that HMGB1 overexpression increased tumour EMT. In summary, our results demonstrated that miR-200c could suppress EMT, invasion, and migration of NSCLC cells by downregulating HMGB1.

Plasma Levels of High-Mobility Group Box 1 during Peptide Vaccination in Patients with Recurrent Ovarian Cancer

High-mobility group box 1 (HMGB1) is a nuclear protein that is known to be secreted into extracellular fluids from injured cells, activated macrophages, and tumor cells. The clinical correlation of circulating HMGB1 levels with various diseases including cancer has been reported. However, there is no information on HMGB1 levels in cancer patients treated with peptide vaccination. In the present study, we investigated the plasma levels of HMGB1 during personalized peptide vaccination in patients with recurrent ovarian cancer. Frozen plasma samples of 39 patients from previously conducted clinical trials were used in this study. HMGB1 levels were decreased after the 1st cycle of vaccination from their prevaccination levels. However, no correlation was observed between HMGB1 and overall survival (OS). The correlation between plasma HMGB1 levels and other biomarker levels was further analyzed by scatter plot, revealing that HMGB1 levels after the 1st cycle of vaccination were significantly correlated with myeloid-derived suppressor cell (MDSC) frequency after the 1st cycle of vaccination (r = 0.357, p = 0.032). Chi-square test showed that epitope spreading was significantly related with changes of HMGB1 (p = 0.030). These results suggest that plasma HMGB1 is a possible biomarker for cancer vaccine therapy, although direct correlation with OS has not been obtained. This trial is registered with Clinical Trial Registry under trial numbers UMIN000003083 and UMIN000001482.

Serum HMGB1 as a Potential Biomarker for Patients with Asbestos-Related Diseases

High-mobility group box 1 (HMGB1) functions as a proinflammatory cytokine and is one of the most intriguing molecules in inflammatory disorders and cancers. Notably, HMGB1 is a potential therapeutic target and novel biomarker in related diseases. However, the diagnostic value of HMGB1 for benign and malignant asbestos-related diseases (ARDs) remains unclear. In this work, we detected preoperative serum HMGB1 levels in Chinese asbestos-exposed (AE) and ARDs populations and further evaluated the diagnostic value of HMGB1 in patients with certain types of ARDs, including those with pleural plaques, asbestosis, or malignant mesothelioma (MM). The experimental data presented that the serum level of HMGB1 was significantly elevated in AE and ARDs subjects. Our findings indicated that serum HMGB1 is a sensitive and specific biomarker for discriminating asbestosis- and MM-affected individuals from healthy or AE individuals. In addition, serum matrix metalloproteinases 2 and 9 are not correlated with HMGB1 in ARDs. Thus, our study provides supporting evidence for HMGB1 as a potential biomarker either for the clinical diagnosis of high-risk AE cohorts or for evaluating ARDs.

Relationship between high-mobility group box 1 overexpression in ovarian cancer tissue and serum: a meta-analysis

OBJECTIVE

To implement a meta-analysis to investigate the relationship between high-mobility group box 1 (HMGB1) overexpression in the tissue and serum of ovarian cancer patients, and to evaluate its prognostic significance.

METHODS

Searches were made of China National Knowledge Infrastructure, EMBASE, WanFang, PubMed, MEDLINE, and Web of Science databases up to August 2015, with no language or style restrictions. Reference lists of related studies were also carefully reviewed to identify additional articles.

RESULTS

The literature search identified a total of 12 relevant studies on HMGB1 expression for inclusion in the meta-analysis: seven in ovarian tumor tissue, four in ovarian tumor patient serum, and one in both tissue and serum. HMGB1 protein levels in ovarian cancer tissues were notably higher than those in normal ovarian tissues with no evidence of heterogeneity between studies (RD=0.64, 95% confidence interval (CI): 0.57-0.70, Z=18.70, P<0.00001, I (2)=15%), and also higher than those in benign tumor tissues with no evidence of heterogeneity between studies (RD=0.52, 95% CI: 0.43-0.61, Z=11.14, P<0.00001, I (2)=0). Serum HMGB1 levels were similarly significantly higher in ovarian cancer patients than those with benign tumors or normal ovaries. Pooled mean differences of HMGB1 in ovarian cancer patients compared with patients with benign tumors or normal ovaries were 99.32 with 95% CI: 67.82-130.81, Z=6.18, P<0.00001, and 95.34 with 95% CI: 62.11-128.57, Z=5.62, P<0.0001. The pooled relative risk of ovarian cancer with high vs low HMGB1 expression levels was 1.40 with 95% CI: 1.09-1.79, Z=2.66, P=0.008, heterogeneity I (2)=50%.

CONCLUSION

This meta-analysis suggested that HMGB1 levels in both tissue and serum of ovarian cancer patients were significantly higher than those of benign tumor and normal ovarian samples. High serum or tissue HMGB1 expression may therefore be an effective molecular marker for ovarian benign or malignant tumor diagnosis and patient prognosis.

High Mobility Group B Proteins, Their Partners, and Other Redox Sensors in Ovarian and Prostate Cancer

Cancer cells try to avoid the overproduction of reactive oxygen species by metabolic rearrangements. These cells also develop specific strategies to increase ROS resistance and to express the enzymatic activities necessary for ROS detoxification. Oxidative stress produces DNA damage and also induces responses, which could help the cell to restore the initial equilibrium. But if this is not possible, oxidative stress finally activates signals that will lead to cell death. High mobility group B (HMGB) proteins have been previously related to the onset and progressions of cancers of different origins. The protein HMGB1 behaves as a redox sensor and its structural changes, which are conditioned by the oxidative environment, are associated with different functions of the protein. This review describes recent advances in the role of human HMGB proteins and other proteins interacting with them, in cancerous processes related to oxidative stress, with special reference to ovarian and prostate cancer. Their participation in the molecular mechanisms of resistance to cisplatin, a drug commonly used in chemotherapy, is also revised.

Clinical impact of high mobility group box 1 protein in epithelial ovarian cancer

PURPOSE

The aim of this study was to confirm the expression of high mobility group box 1 (HMGB1) in patients with epithelial ovarian cancer (EOC) and to evaluate the prognostic significance of HMGB1.

METHODS

A total of 74 patients with EOC comprised our cohort. Retrospectively collected tissue microarray from EOC patients treated with debulking surgery followed by taxane and platinum chemotherapy were analyzed for evaluation of the prognostic significance of HMGB1. Expression of HMGB1 was assessed by immunohistochemistry.

RESULTS

The positive staining was detected in 80% of EOC patients and the rate of high HMGB1 expression was 42%. In advanced stage, patients with high HMGB1 expression showed a poorer prognosis than low HMGB1 expression group [median progression-free survival (PFS), 10.8 vs. 21.7 months, P = 0.005]. High HMGB1 expression was an independent predictor for PFS (P = 0.024).

CONCLUSIONS

HMGB1 expression is expected as a promising biomarker for EOC and further studies are needed to assess potential roles in EOC.

High-mobility group nucleosome-binding protein 1 is a novel clinical biomarker in non-small cell lung cancer

The involvement of alarmin high-mobility group nucleosome-binding protein 1 (HMGN1) in non-small cell lung cancer (NSCLC) is unknown. To address the presence of HMGN1 in the serum of different stages of NSCLC patients and healthy controls, we enrolled a consecutive sample of adult serum at diagnosis and correlated it with clinicopathologic outcomes. A total of 100 NSCLC patients and 23 healthy volunteers were enrolled from January 2012 through December 2013. Serum HMGN1 levels were determined by enzyme-linked immunosorbent assay (ELISA). Additionally, HMGN1 levels in 50 NSCLC patients with early-stage disease who received curative pneumonectomy were correlated with survivals. Kaplan-Meier plots were used to analyze the data. The patients with NSCLC were characterized by significantly higher serum levels of HMGN1 (0.4585 ± 0.0640 ng/ml) compared to those in healthy controls (0.3578 ± 0.0304 ng/ml). The serum HMGN1 levels were 0.4027 ± 0.0271 ng/ml, 0.4604 ± 0.0328 ng/ml, 0.5408 ± 0.0459 ng/ml, and 0.4213 ± 0.0341 ng/ml in patients with TNM stages I, II, IV, and IV, respectively (p < 0.001). There were significant differences among four groups (p < 0.001). Additionally, a positive correlation between serum HMGN1 and tumor stage was found in local disease, while serum HMGN1 level in metastatic NSCLC patients was significantly decreased. The Kaplan-Meier plots showed that patients with high serum HMGN1 had a poorer overall survival (OS) after curative pneumonectomy than those with low serum HMGN1 (p = 0.019). Inflammation triggered by alarmins plays a role in NSCLC pathogenesis. HMGN1 can serve as a useful clinical parameter for evaluating disease progression and predicting the outcomes for early-stage patients with NSCLC undergoing pneumonectomy.