Twist1 accelerates tumour vasculogenic mimicry by inhibiting Claudin15 expression in triple-negative breast cancer.

The up-regulation of EMT regulator Twist1 has been implicated in vasculogenic mimicry (VM) formation in human triple-negative breast cancer (TNBC). Twist1 targets the Claudin15 promoter in hepatocellular carcinoma cells. Claudin family members are related with TNBC. However, the relationship between Claudin15 and VM formation is not clear. In this study, we first found that Claudin15 expression was frequently down-regulated in human TNBC, and Claudin15 down-regulation was significantly associated with VM and Twist1 nuclear expression. Claudin15 down-regulation correlated with shorter survival compared with high levels. Claudin15 silence significantly enhanced cell motility, invasiveness and VM formation in the non-TNBC MCF-7 cells. Conversely, an up-regulation of Claudin15 remarkably reduced TNBC MDA-MB-231 cell migration, invasion and VM formation. We also showed that down-regulation of Claudin15 was Twist1-dependent, and Twist1 repressed Claudin15 promoter activity. Furthermore, GeneChip analyses of mammary glands of Claudin15-deficient mice indicated that Claudin18 and Jun might be downstream factors of Twist1-Claudin15. Our results suggest that Twist1 induced VM through Claudin15 suppression in TNBC, and Twist1 inhibition of Claudin15 might involve Claudin18 and Jun expression.

Function of BMP4 in the Formation of Vasculogenic Mimicry in Hepatocellular Carcinoma.

Vasculogenic mimicry (VM) is linked to vascular invasion of human hepatocellular carcinoma (HCC). BMP4, one BMP family member, is upregulated in several cancers. The purpose of this report is to identify the function of BMP4 in the formation of VM in HCC and the mechanism underling this regulation. In our report, BMP4 up-regulation resulted in an increase in migration, invasion and channel-like structure formation as well as induced epithelial-mesenchymal transition (EMT) process and stem cell-associated proteins OCT4 and SOX2 expression in HCC cells. In addition, The VM-associated proteins, including EphA2, VE-cadherin and MMP2, also could be effectively enhanced by the overexpression of BMP4. Furthermore, according to the TCGA database, higher expression of BMP4 is seen in HCC in contrast to normal liver samples. Immunohistochemistry revealed that BMP4 was positively associated with VM formation, age, histological differentiation, HCC stage, and shorter survival duration. These data demonstrated that BMP4 could promote VM network formation in HCC through induction of stemness in EMT and modulating the EphA2/VE-cadherin/MMP2 signaling pathway.

[Antiendotoxin effect of Jinhuaqingre capsules].

Objective: To investigate the anti-pyretic and anti-endotoxin effect of Chinese herb medicine Jinhuaqingre capsules. Methods: Thirty healthy male New Zealand rabbits with lipopolysaccharide-induced fever were divided into 5 groups (6 rabbits in each): animals in model group were given normal saline by gavage, animals in positive control group were given aspirin (0.2 g/kg), and animals in Jinhuaqingre groups were given Jinhuaqingre capsules 6.0, 3.0 or 1.5 g/kg, respectively. The changes in body temperature of rabbits were observed. Fifty healthy Kunming mice were divided into 5 groups (10 mice in each): mice in model group were given normal saline by gavage, mice in positive control group were given aspirin (0.2 g/kg), and those in Jinhuaqingre groups were given Jinhuaqingre capsules 6.0, 3.0, 1.5 g/kg, respectively. Matrix coloration method was used to detect the degradation rate of endotoxin in mice. Results: The body temperature in rabbits of high and medium dose Jinhuaqingre capsule groups declined significantly 60 min after drug administration, and the temperature of high-dose group returned to the baseline after 300 min; while the body temperature of low-dose group started to decline at 180 min after drug administration. The endotoxin degradation rates in mice of high, medium and low dose groups was (56.73±3.12)%, (47.23±1.77)% and (21.08±2.30)% at 30 min after drug administration; those were (82.76±1.00)%, (64.75±1.77)% and (38.21±1.57)% at 60 min after drug administration, respectively. Conclusion: Chinese herb medicine Jinhuanigre capsules have anti-pyretic and anti-endotoxin effects, which may provide a new option for the treatment of heat-toxin syndrome.

Twist1-related miR-26b-5p suppresses epithelial-mesenchymal transition, migration and invasion by targeting SMAD1 in hepatocellular carcinoma.

UNLABELLED: Twist1 is well known to induce epithelial-mesenchymal transition (EMT) and promote tumor metastasis. MicroRNAs (miRNAs) are involved in the EMT process and are associated with metastasis in hepatocellular carcinoma (HCC). In the present study, microRNA-26b-5p (miR-26b-5p) expression was consistently and significantly downregulated in HepG2-Twist1 HCC cell lines compared with HepG2-vector cell lines using microarrays (the HepG2-Twist1 cell line can stably express Twist1). miR-26b- 5p downregulation was directly mediated by Twist1 through binding to the promoter region of miR-26b-5p in HepG2-Twist1 cells by ChIP-seq technology. Both gain- and loss-of-function studies showed that miR-26b-5p dramatically suppressed EMT and the invasion ability of HCC cells in vitro. Using mouse models, tumors derived from miR- 26b-5p-overexpressed HCC cells exhibited a significant reduction in tumorigenicity compared with the control group. Subsequent investigation revealed that miR-26b-5p directly inhibited SMAD family member 1 (SMAD1) expression. miR-26b-5p repressed BMP4/Smad1 signaling following SMAD1 inhibition. Overexpression of SMAD1 reversed the function of miR-26b-5p. In human HCC tissues and mouse xenograft tumors, miR-26b-5p levels were inversely correlated with SMAD1 expression as well as metastasis. CONCLUSION: miR-26b-5p suppresses Twist1-induced EMT, invasion, and metastasis of HCC cells by targeting SMAD1 and BMP4/Smad1 signaling. This suggests a promising application for miR-26b-5p in anti-HCC therapy.

Regulation of proliferation, angiogenesis and apoptosis in hepatocellular carcinoma by miR-26b-5p.

MicroRNAs (miRNAs) play vital roles in cell proliferation, differentiation and apoptosis in hepatocellular carcinoma (HCC). miR-26b has been confirmed as an important regulator in carcinogenesis and other pathological processes. miR-26b-5p is one member of the mature miR-26 family, and its functional role in proliferation, angiogenesis and apoptosis in HCC remains unknown. Here, we demonstrate that miR-26b-5p expression was significantly decreased in HCC tissues and HCC cell lines compared with normal liver tissues and liver cells by quantitative real-time polymerase chain reaction (qRT-PCR). The relationships between miR-26b-5p and the clinical characteristics of HCC patients were further analysed, and miR-26b-5p was positively correlated with the differentiation of HCC cells. Computational searches were further used to identify the downstream targets and signalling pathways of miR-26b-5p in HCC cells. Cell viability, proliferation and tube formation abilities were assessed by scrape, 3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and three-dimensional culture assays to confirm that miR-26b-5p inhibited HCC cell growth and impaired the tube formation ability of the HCC cells. Both in vitro and in vivo studies showed that miR-26b-5p could suppress vascular mimicry (VM) and angiogenesis by down-regulating the expression of VE-cadherin, Snail and MMP2 and could inhibit the apoptosis of HCC cells. Using mouse models, we revealed that tumours derived from miR-26b-5p-expressing HCC cells displayed a significant decrease in microvessel density compared with those derived from control cells. Therefore, our data provide further insight into the role of miR-26b-5p as a negative regulator of proliferation, angiogenesis, and apoptosis in HCC.

Linearly Patterned Programmed Cell Necrosis Induced by Chronic Hypoxia Plays a Role in Melanoma Angiogenesis.

BACKGROUND: Highly aggressive tumors are exposed to hypoxia and increased tumor interstitial fluid pressure (IFP) conditions which is resistant to blood supply. Physiological responses of the organism may reduce IFP through induction of orderly cell death. SPECIFIC AIMS: This study demonstrates that orderly cell death provided spatial structure for early angiogenesis in the hypoxic, high-IFP tumor microenvironment and the participation of linearly patterned programmed cell necrosis (LPPCN) in nascent melanoma angiogenesis. METHODS: Animal model, laser capture microdissection, wound healing and transwell assays, three-dimensional cultures, zymography assays, western-blotting analysis, immunohistochemistry and RT-PCR were performed. RESULTS: This study demonstrated a special form of cell death occurring in groups of malignant tumor cells which arrayed in lines. Both features of apoptosis and necrosis can be found in this cell death pattern and were termed as LPPCN. Its role as a stimulus of tumor angiogenesis was investigated using human melanoma samples and an animal model. Computer image analysis showed that LPPCN and tumor microvessels had identical spatial distributions. It can be induced by chronic hypoxia, high IFP and subsequent calcium influx. Higher number of tumor associated macrophages (TAM) and VEGF expression were found in the tumor with LPPCN. Based on the tumor-bearing animal model, it was found that block of caspase pathway inhibited LPPCN, microvessel density and vasculogenic mimicry (VM). CONCLUSIONS: LPPCN formation may play an important role in tumor angiogenesis due to stimulation of macrophage infiltration and HIF-1α regulation, and that inhibition of LPPCN may be a novel therapeutic strategy against tumor angiogenesis and metastasis.

USP44+ Cancer Stem Cell Subclones Contribute to Breast Cancer Aggressiveness by Promoting Vasculogenic Mimicry.

Vasculogenic mimicry (VM), a newly defined pattern of tumor blood supply, describes the functional plasticity of aggressive cancer cells that form vascular networks. In our previous study, breast cancer stem cells (CSC) were shown to potentially participate in VM formation. In this study, breast CSCs presented centrosome amplification (CA) phenotype and ubiquitin-specific protease 44 (USP44) upregulation. USP44 expression contributed to the establishment of bipolar spindles in breast CSCs with supernumerary centrosomes by localizing at pole-associated centrosomes. The bipolar spindle patterns of breast CSCs with CA, including planar-like and apico-basal-like, functioned differently during the VM process of CSCs. Moreover, the ability of transendothelial migration in VM-forming cells was increased. In vivo experiment results showed that CSC xenografts presented linearly patterned programmed cell necrosis, which provided a spatial foundation for VM formation as well as angiogenesis. Breast CSCs further showed increased levels of IL6 and IL8. However, USP44 silencing induced spindle multipolarity, abated VM, reduced transendothelial migration, and consequently decreased IL6 and IL8 levels in breast CSCs. Finally, USP44(+) CSC subclones (ALDH1(+)/USP44(+)/IL6(+)/IL8(+)) were identified in breast cancer specimens through consecutive sections scanning. The subclones were related not only to CA, but also to VM. Statistical analysis suggested that USP44(+) CSC subclones could be used as an independent prognostic biomarker of poor clinical outcomes in patients with breast cancer. Collectively, the identification of USP44(+) CSC subclones may contribute to the prediction of VM formation and aggressive behavior. This study provides novel insights into the therapy for advanced breast cancer.

Erythropoietin and erythropoietin receptor in hepatocellular carcinoma: correlation with vasculogenic mimicry and poor prognosis.

To evaluate erythropoietin (Epo) and erythropoietin receptor (EpoR) expression, its relationship with vasculogenic mimicry (VM) and its prognostic value in human hepatocellular carcinoma (HCC), we examined Epo/EpoR expression and VM formation using immunohistochemistry and CD31/PAS (periodic acid-Schiff) double staining on 92 HCC specimens. The correlation between Epo/EpoR expression and VM formation was analyzed using two-tailed Chi-square test and Spearman correlation analysis. Survival curves were generated using Kaplan-Meier method. Multivariate analysis was performed using Cox regression model to assess the prognostic values. Results showed positive correlation between Epo/EpoR expression and VM formation (P < 0.05). Patients with Epo or EpoR expression exhibited poorer overall survival (OS) than Epo-negative or EpoR-negative patients (P < 0.05). Epo-positive/VM-positive and EpoR-positive/VM-positive patients had the worst OS (P < 0.05). In multivariate survival analysis, age, Epo and EpoR were independent prognostic factors related to OS. These results will provide evidence for further research on HCC microcirculation patterns and also will provide new possible targets for HCC diagnosis and treatment.

ZEB2 promotes vasculogenic mimicry by TGF-ß1 induced epithelial-to-mesenchymal transition in hepatocellular carcinoma.

AIMS: Zinc finger E-box binding homeobox 2 (ZEB2), an epithelial-mesenchymal transition (EMT) regulator, has been involved in invasion and metastasis of human tumor. Although EMT may be involved in vasculogenic mimicry (VM) formation, no reports describing the relation between ZEB2 and VM are available. We hypothesize that ZEB2 may promote VM formation in hepatocellular carcinoma (HCC). METHODS AND RESULTS: Paraffin-embedded tumor tissue samples from 92 patients were immunostained with anti-ZEB2 antibody. We found that the ZEB2 nuclear expression was significantly associated with VM formation and metastasis. Patients with VM and ZEB2 nuclear expression had a shorter survival period than those without expression. In vitro, ZEB2 overexpression significantly enhanced cell motility, invasiveness, and VM formation of HepG2 cells. ZEB2 upregulation also increased VE-cadherin, Flt-1, and Flk-1 expression and activated MMPs. ZEB2 knockdown inhibited cell motility, invasiveness, and VM formation in Bel7402 cells. ZEB2 knockdown also decreased VE-cadherin, Flt-1, and Flk-1 expression and MMP activity. In addition, EMT in HepG2 cells was induced by TGF-ß1 treatment, and the kinetics of expression of EMT markers and regulators were assessed by Western blot analysis. The expression of ZEB2 increased significantly, and VM formation was promoted. CONCLUSION: ZEB2 can promote VM formation through the EMT pathway. Our findings may represent a novel therapeutic target in HCC.

Overexpression of Wnt5a promotes angiogenesis in NSCLC.

To evaluate Wnt5a expression and its role in angiogenesis of non-small-cell lung cancer (NSCLC), immunohistochemistry and CD31/PAS double staining were performed to examine the Wnt5a expression and we analyze the relationships between Wnt5a and microvessel density (MVD), vasculogenic mimicry (VM), and some related proteins. About 61.95% of cases of 205 NSCLC specimens exhibited high expression of Wnt5a. Wnt5a expression level was upregulated in the majority of NSCLC tissues, especially in squamous cell carcinoma, while its expression level in adenocarcinoma was the lowest. Wnt5a was also found more frequently expressed in male patients than in female patients. Except for histological classification and gender, little association was found between Wnt5a and clinicopathological features. Moreover, Wnt5a was significantly correlated with prognosis. Overall, Wnt5a-positive expression in patients with NSCLC indicated shorter survival time. As for vascularization in NSCLC, Wnt5a showed close association with VM and MVD. In addition, Wnt5a was positively related with ß -catenin-nu, VE-cadherin, MMP2, and MMP9. The results demonstrated that overexpression of Wnt5a may play an important role in NSCLC angiogenesis and it may function via canonical Wnt signal pathway. This study will provide evidence for further research on NSCLC and also will provide new possible target for NSCLC diagnosis and therapeutic strategies.

A dynamic interplay between alternative polyadenylation and microRNA regulation: implications for cancer (Review).

Alternative polyadenylation and microRNA regulation are both mechanisms of post-transcriptional regulation of gene expression. Alternative polyadenylation often results in mRNA isoforms with the same coding sequence but different lengths of 3' UTRs, while microRNAs regulate gene expression by binding to specific mRNA 3' UTRs. In this sense, different isoforms of an mRNA may be differentially regulated by microRNAs, sometimes resulting in cellular proliferation and this mechanism is being speculated on as a potential cause for cancer development.

A study on the association between C1GALT1 polymorphisms and the risk of Henoch-Schönlein purpura in a Chinese population.

Henoch-Schönlein purpura (HSP) is the most common systemic vasculitis of childhood. The molecular etiology of HSP is not well understood. The purpose of this study is to investigate the association between polymorphisms in C1GALT1 gene and the risk of HSP in a Chinese population. A total of unrelated 542 northern Chinese were enrolled in this study. PCR-RFLP method was used to genotype the five tagging SNPs in the C1GALT1 gene. Chi-squared test and logistic regression analysis were used for the comparison of genotype distribution between cases and controls. The five tagging SNPs were all in Hardy-Weinberg equilibrium in controls. SNP7 was significantly associated with HSP risk, P = 0.005. The DI genotype, compared with the DD genotype, was associated with a significantly higher risk of developing HSP (OR 1.72; 95 % CI 1.11-2.67). The II genotype, compared with the DD genotype, was associated with a significantly higher risk of developing HSP (OR 3.39; 95 % CI 1.16-9.30). Other SNPs were not associated with HSP risk. Variations in the C1GALT1 gene were found to be associated with HSP risk. Further studies are warranted to validate our findings and to investigate into its underlining mechanism.

PDGFRß triggered by bFGF promotes the proliferation and migration of endothelial progenitor cells via p-ERK signalling.

We have examined the effects of bFGF (basic fibroblast growth factor) on p-ERK (phosphorylated extracellular signal-regulated kinase) through PDGFRß (platelet-derived growth factor receptor ß) in the proliferation and migration of EPCs (endothelial progenitor cells). EPC migration was detected using the Transwell system. The expression of PDGFRß mRNA and protein, total ERK and p-ERK proteins was respectively assessed by real-time PCR and Western blottings. bFGF promote the proliferation and migration of EPCs, the effects of bFGF being implemented by activating ERK signalling through the expression of PDGFRß, whereas an anti-bFGF antibody and inhibitor of PDGF (platelet-derived growth factor) receptor kinase (AG1296) could respectively decrease the expression of PDGFRß mRNA and protein and p-ERK protein. Total ERK protein did not change under the same experimental conditions, and an inhibitor of p-ERK (PD98059) inhibited the proliferation and migration of EPCs. The findings strongly suggest that a PDGFRß/p-ERK signalling pathway triggered by bFGF plays an important role in the proliferation and migration of EPCs.

Association between the eNOS gene polymorphisms and rheumatoid arthritis risk in a northern Chinese population.

BACKGROUND: Several genetic polymorphisms in the endothelial nitric oxide synthase (eNOS) gene are associated with the pathogenesis of rheumatoid arthritis (RA). The objective of the present study was to investigate whether the two SNPs (T-786C and G894T) of the eNOS gene are associated with rheumatoid arthritis risk in a northern Chinese population. METHODS: In this study, the eNOS genes T-786C and G894T were studied in 196 cases with rheumatoid arthritis and 201 healthy controls with gender, age and ethnicity matched. The two SNPs were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The analyses of association were statistically compared using the chi-square test with SPSS software for Windows. RESULTS: The frequency of the -786C allele was significantly higher in the rheumatoid arthritis patients than in the healthy controls (19.64% vs. 14.18%, P < 0.05). However, the 894T allele of the eNOS gene was not increased in the rheumatoid arthritis patients compared to the healthy controls. CONCLUSIONS: Individuals with the -786CC genotype have an increased risk of rheumatoid arthritis. Further study with an increased sample size is necessary for the study of the role of this SNP in rheumatoid arthritis.