Increased HMGB1 expression correlates with higher expression of c-IAP2 and pERK in colorectal cancer

Intestinal Epithelia and Myeloid Immune Cells Shape Colitis Severity and Colorectal Carcinogenesis via High-mobility Group Box Protein 1

BACKGROUND

High-mobility group box protein 1 [HMGB1] is a ubiquitous nucleoprotein with immune-regulatory properties following cellular secretion or release in sterile and in infectious inflammation. Stool and serum HMGB1 levels correlate with colitis severity and colorectal cancer [CRC] progression, yet recent reports indicate that HMGB1 mainly operates as an intracellular determinant of enterocyte fate during colitis, and investigations into the roles of HMGB1 in CRC are lacking.

METHODS

Using mice with conditional HMGB1-knockout in enterocytes [Hmgb1ΔIEC] and myeloid cells [Hmgb1ΔLysM], respectively, we explored functions of HMGB1 in pathogenetically diverse contexts of colitis and colitis-associated CRC.

RESULTS

HMGB1 is overexpressed in human inflammatory bowel disease and gastrointestinal cancers, and HMGB1 protein localises in enterocytes and stromal cells in colitis and CRC specimens from humans and rodents. As previously described, enterocyte HMGB1 deficiency aggravates severe chemical-induced intestinal injury, but not Citrobacter rodentium or T cell transfer colitis in mice. HMGB1-deficient enterocytes and organoids do not exhibit deviant apoptotic or autophagic activity, altered proliferative or migratory capacity, abnormal intestinal permeability, or aberrant DSS-induced organoid inflammation in vitro. Instead, we observed altered in vivo reprogramming of both intestinal epithelia and infiltrating myeloid cells in Hmgb1ΔIEC early during colitis, suggesting HMGB1-mediated paracrine injury signalling. Hmgb1ΔIEC had higher CRC burden than wild types in the Apc+/min model, whereas inflammatory CRC was attenuated in Hmgb1ΔLysM. Cellular and molecular phenotyping of Hmgb1ΔIEC and Hmgb1ΔLysM cancers indicates context-dependent transcriptional modulation of immune signalling and extracellular matrix remodelling via HMGB1.

CONCLUSION

Enterocytes and myeloid cells context-dependently regulate host responses to severe colitis and maladaptive intestinal wound healing via HMGB1.

The Role of High Mobility Group Box B-1 in the Prognosis of Colorectal Cancer Based on the Changes in the Intestinal Mucosal Barrier

Background: To investigate the expression of high mobility group box B-1 (HMGB-1) in patients with colorectal cancer (CRC) and its association with clinicopathological features and prognosis in colorectal carcinoma by combining bioinformatics and clinical data analysis, and to clarify the role of HMGB-1. To examine whether HMGB-1 expression is related to the damage of the intestinal mucosal barrier, and then explore the potential HMGB-1-dependent mechanisms affecting the progression of CRC. Methods: CRC datasets of GSE12945, GSE17536, and GSE17537 from the public gene chip database were screened and downloaded. Clinical information and CRC tissue samples from patients with stage I-III CRC from the hospital were collected. Serum samples of patients were applied by enzyme-linked immunosorbent assay on HMGB-1, and were divided into high and low HMGB-1 expression, which was examined by 16S rDNA sequencing. Immunohistochemistry was performed to examine the relationship between the expression of HMGB-1 and tight junction protein, occludin, tumor necrosis factor-α, and interferon-γ. Results: Based on the Cutoff value of 10.24 ng/mL, the CRC patients were divided into high and low expression groups. In the HMGB-1H patient group, the TNM staging, overall survival, disease-free survival, recurrence, and metastasis were inferior to the HMGB-1L group. The results of 16S rDNA sequencing demonstrated that the Providencia genus was found to be enriched in the HMGB-1L group. Immunohistochemical results showed that HMGB-1 expression was negatively correlated with the expression of ZO-1 and occludin (R = 0.035, R = 0.003, P < .05), but was positively correlated with the expression of TNF-α and IFN-γ (R = 0.016, R = 0.001, P < .05). Conclusion: The survival of CRC patients with positive HMGB-1 expression was significantly shortened, which may be related to the decrease of Rovitensis content, the decreased expression of ZO-1 and occludin, and the increased levels of TNF-α and IFN-γ, which in turn damage the intestinal mucosal barrier, leading to the development of CRC.

Upregulation of HMGB1 in tumor-associated macrophages induced by tumor cell-derived lactate further promotes colorectal cancer progression

BACKGROUND

Lactate accumulation leads to an acidic tumor microenvironment (TME), in turn promoting colorectal cancer (CRC) progression. Tumor-associated macrophages (TAMs) are the predominant cells in TME. This study aimed to reveal the regulation mechanism of CRC cell-derived lactate on TAMs and explore the mechanism underlying lactate accumulation-induced aggravation in CRC.

METHODS

Cell growth and metastasis were evaluated by colony formation, Transwell, and wound healing assays. Western blot and RT-qPCR were applied to determine the protein and mRNA expression. Flow cytometry was used to analyze the polarization state and apoptotic rate of macrophages induced in THP-1 cells. The lactate in the cell supernatant was quantified using an ELISA kit. Immunofluorescence was performed to visualize the location of High Mobility Group Box 1 (HMGB1). H&E and Ki67 staining assays were used to assess tumorigenesis in nude mice bearing ectopic tumors.

RESULTS

Cell growth and metastasis were promoted in the hypoxic CRC cells. The hypoxic cell supernatant stimulated the M2-type polarization of macrophages. The lactate level increased in hypoxic cancer cells. However, the inhibition of lactate using 3-hydroxy-butyrate (3-OBA) reversed the effects of hypoxia. Also, macrophages showed no promoting effect on cancer cell growth and migration in the presence of 3-OBA. HMGB1 was secreted into the extracellular space of lactate-induced macrophages, further enhancing the malignant behaviors of cancer cells. ERK, EMT, and Wnt signaling pathways were activated in cancer cells due to HMGB1 upregulation.

CONCLUSIONS

The lactate metabolized by cancer cells stimulated M2 polarization and HMGB1 secretion by macrophages, aggravating the carcinogenic behaviors of cancer cells.

Co-expression of High-mobility group box 1 protein (HMGB1) and receptor for advanced glycation end products (RAGE) in the prognosis of esophageal squamous cell carcinoma

Esophageal cancer is a malignant type of cancer with a high mortality rate. The aim of this study is to determine co-expression patterns of High-mobility group box 1 protein (HMGB1) and receptor for advanced glycation end products (RAGE) in ESCC (esophageal squamous cell carcinoma) conditions and their prognostic role in cancer progression. The expression of HMGB1 and RAGE in ESCC tissues has been analyzed using qRT-PCR and Western blotting. Co-localized expression patterns of HMGB1 and RAGE in ESCC tissues were determined using immunohistochemistry and analyzed for clinical-pathological parameters. Overall survival was performed based on co-expression of HMGB1 and RAGE proteins. A higher expression pattern of HMGB1, and RAGE was observed at mRNA and protein level in the ESCC group compared to the adjacent tissue group. Expression of HMGB1 was significantly correlated with lymph node, metastasis, lymphatic invasion, and venous invasion (p < 0.05). RAGE expression exhibited a significant correlation with venous invasion. Overall survival was significantly shorter (P < 0.05) in the patients with co-expression of HMGB1 and RAGE compared to the patients without co-expression. A significant difference in the overall survival was evident between the patients with co-expression of HMGB1 and RAGE and the patients without coexpression. HMGB1 and RAGE expression patterns were associated with aggressive metastatic characteristics of ESCC. The co-expression of HMGB1 and RAGE was correlated with shorter survival times. Results concluded the co-expression patterns of HMGB1 and RAGE exhibited a prognostic relevance in ESCC conditions.

Long non-coding RNA DCST1-AS1/hsa-miR-582-5p/HMGB1 axis regulates colorectal cancer progression

Long non-coding RNAs (lncRNAs) are related to the initiation and progression of tumor and regulate various cellular processes including growth, invasion, migration, and apoptosis. Understanding the roles and mechanisms of lncRNAs in regulating cancer progression is crucial for formulating novel therapeutic strategies. Although lncRNA DCST1-antisense RNA 1(AS1) has been implicated in several cancers, its role in the progression of colorectal cancer (CRC) remains to be explored. This study focuses on elucidating the function of lncRNA DCST1-AS1 in CRC development and its underlying mechanism. We found that the expression of lncRNA DCST1-AS1 was up-regulated in CRC tissues and cell lines, and CRC patients with high lncRNA DCST1-AS1 expression were associated with a poor prognosis. Loss-of-function and gain-of-function experiment in CRC cell lines confirmed that lncRNA DCST1-AS1 promoted the malignant phenotype of CRC cells, including cell proliferation, colony formation, migration, and invasion. In addition, we identified the binding sites between lncRNA DCST1-AS1 and hsa-miR-582-5p, and between hsa-miR-582-5p and High Mobility Group Box 1 (HMGB1) through DIANA Tools and TargetScan database, which was further confirmed by dual-luciferase reporter assay. Functional assay further confirmed the crucial role of lncRNA DCST1-AS1/hsa-miR-582-5p/HMGB1 axis in modulating the malignant phenotype of CRC cells. Collectively, our data suggest that lncRNA DCST1-AS1 regulates the aggressiveness of CRC cells through hsa-miR-582-5p/HMGB1 axis. Our study provides novel insight into the mechanism of lncRNA DCST1-AS1 in CRC cells for targeted therapy.

Pharmacological Inhibition of HMGB1 Prevents Muscle Wasting

Background: Cachexia is a multifactorial disorder characterized by weight loss and muscle wasting, making up for about 20% of cancer-related death. However, there are no effective drugs to combat cachexia at present.

Methods: In this study, the effect of CT26 exosomes on C2C12 myotubes was observed. We compared serum HMGB1 level in cachexia and non-cachexia colon cancer patients. We further explored HMGB1 expression level in CT26 exosome. We added recombinant HMGB1 to C2C12 myotubes to observe the effects of HMGB1 on C2C12 myotubes and detected the expression level of the muscle atrophy-related proteins. Then, we used the HMGB1 inhibitor glycyrrhizin to reverse the effects of HMGB1 on C2C12 myotubes. Finally, HMGB1 inhibitor glycyrrhizin was utilized to relieve cachexia in CT26 cachexia mouse model.

Results: Exosomes containing HMGB1 led to muscle atrophy with significantly decreased myotube diameter and increased expression of muscle atrophy-related proteins Atrogin1 and MuRF1. Further, we detected that HMGB1 induced the muscle atrophy mainly via TLR4/NF-κB pathway. Administration of the HMGB1 inhibitor glycyrrhizin could relieve muscle wasting in vitro and attenuate the progression of cachexia in vivo.

Conclusion: These findings demonstrate the cachectic role of HMGB1, whether it is soluble form of HMGB1 or secreted from tumor cells as part of exosomes. HMGB1 inhibitor glycyrrhizin might be a promising drug in colon cancer cachexia.

The role of miR-129-5p in cancer: a novel therapeutic target

MiRNA-129-5p belongs to the microRNA-129 (miRNA-129) family. MiRNA-129-5p is expressed in many tissues and organs of the human body, and it regulates a wide range of biological functions. The abnormal expression of miRNA-129-5p is related to the occurrence and development of a variety of malignant tumors. MiRNA-129-5p plays an important role in the tumorigenesis process and functions by promoting or inhibiting tumors. However, the role of miRNA-129-5p in cancer remains controversial. This article reviews the different biological functions of miRNA-129-5p in cancer and provides ideas for research in this field to guide the development of targeted therapies and drugs for malignant tumors.

RNA sequencing identified novel target genes for Adansonia digitata in breast and colon cancer cells

Adansonia digitata exhibits numerous beneficial effects. In the current study, we investigated the anti-cancer effects of four different extracts of A. digitata (polar and non-polar extracts of fruit powder and fibers) on the proliferation of human colon cancer (HCT116), human breast cancer (MCF-7), and human ovarian cancer (OVCAR-3 and OVCAR-4) cell lines. RNA sequencing revealed the influence of the effective A. digitata fraction on the gene expression profiles of responsive cells. The results indicated that only the polar extract of the A. digitata fibers exhibited anti-proliferative activities against HCT116 and MCF-7 cells, but not ovarian cancer cells. Moreover, the polar extract of the fibers resulted in the modulation of the expression of multiple genes in HCT116 and MCF-7 cells. We propose that casein kinase 2 alpha 3 (CSNK2A3) is a novel casein kinase 2 (CSNK2) isoform in HCT116 cells and report, for the first time, the potential involvement of FYVE, RhoGEF, and PH domain-containing 3 (FGD3) in colon cancer. Together, these findings provide evidence supporting the anti-cancer potential of the polar extract of A. digitata fibers in this experimental model of breast and colon cancers.

Long Non-Coding RNA PITPNA-AS1 Accelerates the Progression of Colorectal Cancer Through miR-129-5p/HMGB1 Axis

Background

Long non-coding RNAs (lncRNAs) are essential regulators in colorectal cancer (CRC) progression. This work aimed to delve into the characteristics of lncRNA PITPNA-AS1 in CRC.

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) was adopted to examine PITPNA-AS1, miR-129-5p, high-mobility group box-1 (HMGB1) mRNA expressions in CRC tissues and cell lines. Functionally, cell counting kit-8 (CCK-8) and 5-ethynyl-2-deoxyuridine (EdU) incorporation assays were employed to examine cell proliferation; wound healing assay was utilized to detect cell migration; and flow cytometry was used to detect the cell apoptosis. Luciferase reporter assay, RNA immunoprecipitation assay and Western blot were conducted to detect the regulatory relationships among PITPNA-AS1, miR-129-5p and HMGB1.

Results

PITPNA-AS1 and HMGB1 mRNA expressions were observably elevated in CRC tissues and cell lines. Knocking down PITPNA-AS1 could significantly inhibit cell proliferation and migration, and promote apoptosis of CRC cells. PITPNA-AS1 could serve as a competitive endogenous RNA, and up-regulate HMGB1 expression by adsorbing miR-129-5p.

Conclusion

PITPNA-AS1 can expedite CRC cell proliferation and migration, and inhibit apoptosis through miR-129-5p/HMGB1 axis.

Subcellular localization of HMGB1 in colorectal cancer impacts on tumor grade and survival prognosis

The high-mobility group box-1 (HMGB1) protein is implicated in the development of various cancers and their proliferation. According to its function, HMGB1 shuttles between the cell nucleus and cytoplasm, assisting with nucleosome stabilization and gene transcription, or localizing in the cell membrane for outgrowth. The clinicopathologic and prognostic significance of these different subcellular locations and their correlation has been unclear in colorectal cancer (CRC). We found significantly higher rates of nuclear HMGB1 expression in CRC and colorectal adenoma tissue samples (84.0% and 92.6%, respectively) than in normal colorectal tissue (15.0%) and a significantly higher rate of positive cytoplasmic HMGB1 expression in CRC tissue (25.2%) compared with colorectal adenoma (11.8%) and normal colorectal tissue (0.0%). Positive cytoplasmic HMGB1 expression was associated with high-grade CRC, a poor prognosis, and was negatively correlated with strongly positive nuclear HMGB1 expression in CRC tissue specimens (r = – 0.377, P = 0.000). CRC patients with strongly positive nuclear HMGB1 expression had a better survival prognosis than other CRC patients. Preventing nuclear plasma translocation of HMGB1 may be a new strategy for CRC management.

HMGB1 as a therapeutic target in disease

High-mobility group box 1 (HMGB1) was initially recognized as a ubiquitous nuclear protein involved in maintaining the nucleosome integrity and facilitating gene transcription. HMGB1 has since been reevaluated to be a prototypical damage-associated molecular pattern (DAMP) protein, and together with its exogenous counterpart, pathogen-associated molecular pattern (PAMP), completes the body's alarmin system against disturbances in homeostasis. HMGB1 can be released into the extracellular matrix (ECM) by either granulocytes or necrotic cells to serve as a chemotaxis/cytokine during infection, endotoxemia, hypoxia, ischemia-reperfusion events, and cancer. Different isoforms of HMGB1 present with distinctive physiological functions in ECM-fully-reduced HMGB1 (all thiol) acts as the initial damage signal to recruit circulating myeloid cells, disulfide HMGB1 behaves as a cytokine to activate macrophages and neutrophils, and both signals are turned off when HMGB1 is terminally oxidized into the final sulfonate form. Targeting HMGB1 constitutes a favorable therapeutic strategy for inflammation and inflammatory diseases. Antagonists such as ethyl pyruvate inhibit HMGB1 by interfering with its cytoplasmic exportation, while others such as glycyrrhizin directly bind to HMGB1 and render it unavailable for its receptors. The fact that a mixture of different HMGB1 isoforms is present in the ECM poses a challenge in pinpointing the exact role of an individual antagonist. A more discriminative probe for HMGB1 may be necessary to advance our knowledge of HMGB1, HMGB1 antagonists, and inflammatory-related diseases.

Upregulation of microRNA-204 improves insulin resistance of polycystic ovarian syndrome via inhibition of HMGB1 and the inactivation of the TLR4/NF-κB pathway

There is growing evidence of the position of microRNAs (miRs) in polycystic ovarian syndrome (PCOS), thus our objective was to discuss the impact of miR-204 on insulin resistance (IR) in PCOS by targeting highmobility group box protein 1(HMGB1)-mediated toll-like receptor 4(TLR4)/nuclear factor-kappa B (NF-κB) pathway.PCOS-IR patients and PCOS non-insulin resistance (PCOS-NIR) patients were included. The levels of serum sex hormones and related insulin were measured, the expression of miR-204, HMGB1, TLR4 and NF-κB p65 was detected, the diagnostic efficacy of miR-204 in PCOS-IR was analyzed, and the correlation between the expression of miR-204 in PCOS-IR and fasting blood glucose (FPG), fasting insulin (FINS), homeostasis model of assessment for insulin resistance index (HOMA-IR) was analyzed. Both in vitro and in vivo experiments were performed to elucidate the capabilities of miR-204 and HMGB1 in proliferation and apoptosis of PCOS-IR granulosa cells.MiR-204 was lowly expressed as well as HMGB1, TLR4 and NF-κB p65 were highly expressed in PCOS-IR patients. Follicule-stimulating hormone was downregulated, while luteinizing hormone, estrogen, progesterone, FPG, FINS and HOMA-IR were elevated in PCOS-IR. Upregulation of miR-204 and downregulation of HMGB1 could repress TLR4/NF-κB pathway activation, degraded insulin release and testosterone (T) leveland ascended ovarian coefficient, boosted cell proliferation and restrained apoptosis of granulosa cells. Overexpression of HMGB1 reverses the effect of upregulation of miR-204 on IR of PCOS.Our study presents that high expression of miR-204 or inhibition of HMGB1 can improve IR of PCOS via the inactivation of TLR4/NF-κB pathway.

The Use of Murine Models for Studying Mechanistic Insights of Genomic Instability in Multiple Myeloma

Multiple myeloma (MM) is a B-cell malignancy characterized by the accumulation of clonal plasma cells in the bone marrow. In normal plasma cell development, cells undergo programmed DNA breaks and translocations, a process necessary for generation of a wide repertoire of antigen-specific antibodies. This process also makes them vulnerable for the acquisition of chromosomal defects. Well-known examples of these aberrations, already seen at time of MM diagnosis, are hyperdiploidy or the translocations involving the immunoglobulin heavy chain. Over the recent years, however, novel aspects concerning genomic instability and its role in tumor development, disease progression and nascence of refractory disease were identified. As such, genomic instability is becoming a very relevant research topic with the potential identification of novel disease pathways. In this review, we aim to describe recent studies involving murine MM models focusing on the deregulation of processes implicated in genomic instability and their clinical impact. More specifically, we will discuss chromosomal instability, DNA damage and repair responses, development of drug resistance, and recent insights into the study of clonal hierarchy using different murine MM models. Lastly, we will discuss the importance and the use of murine MM models in the pre-clinical evaluation of promising novel therapeutic agents.