The Role of Connexin Hemichannels in Inflammatory Diseases.

The connexin protein family consists of approximately 20 members, and is well recognized as the structural unit of the gap junction channels that perforate the plasma membranes of coupled cells and, thereby, mediate intercellular communication. Gap junctions are assembled by two preexisting hemichannels on the membranes of apposing cells. Non-junctional connexin hemichannels (CxHC) provide a conduit between the cell interior and the extracellular milieu, and are believed to be in a protectively closed state under physiological conditions. The development and characterization of the peptide mimetics of the amino acid sequences of connexins have resulted in the development of a panel of blockers with a higher selectivity for CxHC, which have become important tools for defining the role of CxHC in various biological processes. It is increasingly clear that CxHC can be induced to open by pathogen-associated molecular patterns. The opening of CxHC facilitates the release of damage-associated molecular patterns, a class of endogenous molecules that are critical for the pathogenesis of inflammatory diseases. The blockade of CxHC leads to attenuated inflammation, reduced tissue injury and improved organ function in human and animal models of about thirty inflammatory diseases and disorders. These findings demonstrate that CxHC may contribute to the intensification of inflammation, and serve as a common target in the treatments of various inflammatory diseases. In this review, we provide an update on the progress in the understanding of CxHC, with a focus on the role of these channels in inflammatory diseases.

NUT midline carcinoma as a primary lung tumor treated with anlotinib combined with palliative radiotherapy: a case report.

BACKGROUND: NUT (nuclear protein in testis) midline carcinoma (NMC) is a rapidly progressive tumor arising from midline structures. Recent cases have reported that the poor prognosis with a median survival of 6.7 months and a 2 years overall survival of 19% due to limited treatment. Based on the effect of arotinib on inhibiting tumor growth and angiogenesis. We present one patient case treated with anlotinib and radiotherapy. CASE PRESENTATION: Here, we describe a 33-year old patient who complained of cough and chest pain and was diagnosed as a pulmonary NMC through CT scan, FISH and immunohistochemistry. In addition, we initially demonstrated that anlotinib combined with palliative radiotherapy could significantly prevent the tumor growth in a pulmonary NMC. CONCLUSION: The report indicated that anlotinib combined with palliative radiotherapy could inhibit the tumor progression in a pulmonary NMC, which may provide a combined therapy to pulmonary NMC in the future.

A self-matting waterborne polyurethane coating with admirable abrasion-resistance.

Due to the paradox between abrasion-resistance and extinction, the development of a self-matting waterborne polyurethane (SMWPU) coating accompanied by excellent abrasion-resistance is still a challenge. Herein, a kind of hydroxyalkyl-terminated polysiloxane modified SMWPU was prepared and employed for matting leather/synthetic leather finishing. Simultaneously, the influences of hydrophilic chain extender and polysiloxane loadings on the matting effect and abrasion resistance of the coating were investigated in detail. The results indicated that the gloss of the coating was closely related to the hydrophilic chain extender content, and a stable emulsion and optimal matting effect could be achieved when a 1.6 wt% (based on solid content) hydrophilic chain extender was employed. With the introduction of polysiloxane, the silicon element content on the coating surface increased from 0% to 9.26%, just as expected, and an enhanced abrasion resistance of the coating was obtained. Specifically, the coating weight loss ratio was reduced from 2.36 wt% to 0.41 wt%, and obvious surface damage did not occur after 500 abrasions. Although the surface roughness and matting effect of the coating decreased slightly due to the introduction of silicone, the gloss of the modified coating was less than 1.5° (60° incidence angle), still exhibiting an excellent matting effect. Another interesting result was the elevation of anti-hot-pressing, compared with that of the unmodified one, and the gloss of the modified coating showed no changes under a 10 MPa, 150 °C hot-pressing condition.

CD24hiCD38hi B regulatory cells from patients with end plate inflammation presented reduced functional potency.

Problem due to disc degeneration is frequently found in the aging population. However, severe pain and accompanying end plate inflammation is only found in a small subset of patients, who can be of a younger age than most people with severe disc degeneration, with no apparent cause. We hypothesized that deficiencies in B regulatory (Breg) cells might contribute to the aberrant inflammation in these patients. However, we found that the frequency of CD24hiCD38hi Breg cells was significantly higher in patients than in controls. To investigate Breg function, CD24hiCD38hi Breg cells were stimulated via CD40L/αIg and via Staphylococcus aureus Cowan. Interestingly, the expression of IL-10 and TGF-ß1 was significantly lower in patients than in controls. The expression of PD-L1 was comparable between patient CD24hiCD38hi Bregs and control CD24hiCD38hi Bregs. Control CD24hiCD38hi Bregs, but not patient CD24hiCD38hi Bregs, could suppress the expression of TBX21 and RORC2 in stimulated CD4+ T cells, in a manner that was dependent on IL-10 and PD-L1. The expression of FOXP3, on the other hand, was dependent on TGF-ß. In addition, PD-L1 reduced the viability of CD4+ T cells. Together, we demonstrated that the patients with end plate inflammation did not present a reduction in CD19+CD24hiCD38hi Breg frequency, but presented a reduction in CD19+CD24hiCD38hi Breg function.

Mediastinal follicular dendritic cell sarcoma: a rare, potentially under-recognized, and often misdiagnosed disease.

BACKGROUND: Mediastinal follicular dendritic cell sarcoma (FDCS) is extremely rare. Due to potential under-recognization of this disease, it happens to be misdiagnosed, especially on core needle biopsy. We report 3 cases of mediastinal FDCS and provide a literature review to improve better understanding of the tumor and to reduce misdiagnosis. METHODS: Three cases of mediastinal FDCS in our clinic practice were studied, including their core needle biopsy and resected specimens, and those cases reported previously in English literature were retrieved and analyzed. RESULTS: The core needle biopsy of case 1 showed a tumor reminiscent of classical Hodgkin's lymphoma (CHL), while the resected mass was finally diagnosed with FDCS combined with hyaline-vascular Castleman's disease. Both the biopsy and resected tissue of case 2 were constitutive of the clear epithelioid cells with marked atypia. In both cases, definitive diagnoses were not made on core needle biopsy. In case 3, there were some areas morphologically similar to CHL, and some areas contained ovoid to spindle-shaped tumor cells with fascicular pattern. The analysis of 43 cases of mediastinal FDCS showed the age of patients were from 16 to 76 years old, the male to female ratio was 1.5:1, the maximal tumor diameters were 3-17 cm. 18 cases were underwent preoperative biopsy, whereas 15 (83.3%) of which were misdiagnosed initially, often as lymphoma. 32 patients had available follow-up data, the rates of recurrence, metastasis, and mortality were 12.5, 18.8 and 28.1%, respectively. Current limited data suggested no statistical differences between adverse prognosis and gender, age, tumor size, necrosis, or different therapeutics, respectively. CONCLUSIONS: Mediastinal FDCS is a rare malignancy that has yet not been fully understood and been often misdiagnosed, particularly when making a diagnosis on core needle biopsy. Increased awareness of this enigmatic tumor is crucial to avoid diagnostic pitfalls.

Pregnane X receptor is associated with unfavorable survival and induces chemotherapeutic resistance by transcriptional activating multidrug resistance-related protein 3 in colorectal cancer.

BACKGROUND: Although chemotherapy represents a predominant anti-cancer therapeutic modality, drug treatment efficacy is often limited due to the development of resistant tumor cells. The pregnane X receptor (PXR) affects chemotherapeutic effects by regulating targets involved in drug metabolism and transportation, but the regulatory mechanism is poorly understood. METHODS: Oxaliplatin (L-OHP) content in tumor cells was analyzed by mass cytometry. The roles of PXR on cancer cell proliferation, apoptosis and tumor growth with L-OHP-treated were investigated by MTS, colony formation, flow cytometry and xenograft tumor assays. Luciferase reporter, Chromatin-immunoprecipitation and Site-directed mutagenesis were evaluated the mechanisms. The PXR and multidrug resistance-related protein 3 (MRP3) expressions were examined by western blot, RT-PCR or immunohistochemistry of TMA. Kaplan-Meier and Cox regression were adopted to analyze the prognostic value of PXR in colorectal cancer (CRC). RESULTS: PXR over-expression significantly increased oxaliplatin (L-OHP) transport capacity with a reduction of its content and repressed the effects of L-OHP on tumour cell proliferation and apoptosis. Conversely, PXR knockdown augments L-OHP-mediated cellular proliferation and apoptosis. Moreover, PXR significantly reduced the therapeutic effects of L-OHP on tumor growth in nude mice. Further studies indicated a positive correlation between PXR and MRP3 expression and this finding was confirmed in two independent cohorts. Significantly increased MRP3 expression was also found in PXR over-expressing cell lines. Mechanistically, PXR could directly bind to the MRP3 promoter, activating its transcription. The PXR binding sites were determined to be at -796 to -782bp (CTGAAGCAGAGGGAA) and the key binding sites were the "AGGGA" (-787 to -783bp) on the MRP3 promoter. Accordingly, blockade of MRP3 diminishes the effects on drug resistance of PXR. In addition, PXR expression is significantly associated with poor overall survival and represents an unfavorable and independent factor for male or stage I + II CRC patient prognosis. CONCLUSIONS: PXR is a potential biomarker for predicting outcome and activates MRP3 transcription by directly binding to its promoter resulting in an increased L-OHP efflux capacity, and resistance to L-OHP or platinum drugs in CRC. Our work reveals a novel and unique mechanism of drug resistance in CRC.

Decreased expression of C10orf10 and its prognostic significance in human breast cancer.

Breast cancer is a common malignant tumor, which severely threatens the health of women with an increasing incidence in many countries. Here, we identified C10orf10 as a novel differentially expression gene using expression microarray screening. The expression analysis indicated that C10orf10 was frequently decreased in human breast cancers compared to noncancerous breast tissues (81/95, P = 0.0063). Kaplan-Meier analysis indicated that patients with low C10orf10 expression showed a poorer prognosis both in mRNA (n = 1115, P = 0.0013) and protein (n = 100, P = 0.003) levels. Univariate and multivariate analysis showed that the C10orf10 expression was an independent prognostic factor for overall survival of breast cancer patients. Further analysis revealed that low expression of C10orf10 was an unfavorable factor for the prognosis of the patients who were luminal A, luminal B, Her2+ subtypes, at histological grade 2, lymph node negative and ER positive. Our data provided the first evidence that C10orf10 expression was frequently decreased in breast cancer tissues, and low expression of C10orf10 may be an important prognostic factor for poorer survival time of breast cancer patients.

Identification of ITGB4BP as a new interaction protein of P311.

AIMS: P311 is an 8 kDa protein that has been shown to be of importance in the process of myofibroblast transformation, glioblastoma invasion and nerve regeneration. However, the interaction protein of P311 has yet to be found. The purpose of this study was to find the interactive protein of P311. MAIN METHODS: The yeast two-hybrid system was used for screening the potential interaction proteins of P311. Joint expression of the potential interactive protein and P311 was immunohistochemically stained. The interaction between P311 and the selected protein was further confirmed by fluorescence resonance energy transfer (FRET) in pulmonary adenocarcinoma tissue sections, and by coimmunoprecipitation in HEK293. KEY FINDINGS: Integrin ß4 binding protein (ITGB4BP) was confirmed as the interaction protein of P311. Co-expression and interaction of ITGB4BP and P311 were demonstrated in pulmonary adenocarcinoma by both immunohistochemistry and FRET. Moreover the interaction between P311 and ITGB4BP was demonstrated by coimmunoprecipitation in HEK293. SIGNIFICANCE: The interactions between P311 and ITGB4BP may be very important in the process of tumor cell differentiation and metastasis. ITGB4BP may provide a potential new target for the therapy of tumors.

Human malignant glioma cells expressing functional formylpeptide receptor recruit endothelial progenitor cells for neovascularization.

Endothelial progenitor cells (EPCs) are involved in tumor neovascularization with undefined mechanisms. In this study, we explored the role of formylpeptide receptor, a G protein-coupled receptor, expressed by human malignant glioma cells in neovascularization of malignant glioma. EPCs were isolated from human umbilical cord blood and their migratory capability and tubulogenesis induced by the supernatant of U87 glioblastoma (GBM) cell line were examined. We also assessed the recruitment and incorporation of EPCs into orthotopic intracranial tumors formed by implanted U87 GBM cells. The supernatant of control U87 cells induced high levels of migration and tubule-formation in vitro by EPCs. In contrast, the chemotactic and tubule-stimulating activities on EPCs in the supernatant of U87 cells with FPR knocking down by small interference (si) RNA were significantly attenuated. In addition, the number of EPCs recruited and incorporated into intracranial glioma xenografts was significantly higher in tumors formed by control U87 cells than tumors formed by U87 cells containing FPR-siRNA. Our results suggest that expression of functional FPR in glioma cells plays an important role in regulating vasculogenesis by EPCs, which constitute a novel target for anti-angiogenic therapy in gliomas.

Overexpression and gender-specific differences of SRC-3 (SRC-3/AIB1) immunoreactivity in human non-small cell lung cancer: an in vivo study.

Steroid receptor coactivator-3 (SRC-3) has been reported to be overexpressed in the development and progression of many tumor types. SRC-3 has been detected in several lung cancer cell lines, but its expression and clinical significance in non-small cell lung cancer (NSCLC) remain unclear. In this study, 48 NSCLC tissues were collected and tissue microarrays were performed. The expression of SRC-3 was examined using nickel-intensified IHC. The results showed that of these 48 cases, 18 (37.5%) exhibited high levels of SRC-3 immunoreactivity, 23 (47.9%) exhibited moderate levels of SRC-3 immunoreactivity, and 7 (14.6%) were negative; thus, the total frequency of SRC-3 overexpression was 85.4% (41/48). This SRC-3 overexpression frequency was similar to the overexpression frequency observed for squamous cell carcinoma and adenocarcinoma (82.1% vs 90%) and for metastasis and non-metastasis patients (84.6% vs 85.7%). Data analysis demonstrated a significantly higher overexpression frequency in male patients compared with that in female patients (88.6% vs 76.9%). However, female patients tended to have higher expression levels of SRC-3, as measured by immunoreactivity, than male patients. These results demonstrate a high frequency of SRC-3 overexpression in NSCLC with a gender difference, suggesting that there is a specific role for SRC-3 in the pathogenesis of NSCLC.

[Vasculogenic potential of endothelial progenitor cells derived from human umbilical cord blood and their roles in neovascularization of malignant glioma].

OBJECTIVE: To investigate vasculogenic potential of endothelial progenitor cells (EPCs) derived from human umbilical cord blood and their contribution to the neovascularization of malignant glioma in vivo. METHODS: EPCs were isolated from human umbilical cord blood by density gradient centrifugation. After 7-10 days of culture, EPCs were investigated for CD34 and VEGFR-2 expression by direct immunofluoresent staining. The proliferative activity, migratory capability and forming capillary-like tubules were also monitored after stimulation with VEGF(50 mg/L) in vitro. Moreover, EPCs were administered into tumor-bearing mice, and the tumor and mouse organs were examined under confocal laser scanning microscope to visualize the distribution and localization of transplanted EPCs. In order to quantity the incorporation of EPCs into tumor vessels, cryosections of the tumor tissue were double-labelled with antihuman CD31 and anti-mouse CD31. RESULTS: After 7 to 10 days of culture, EPCs assumed cobblestone-like monolayer growth pattern with nearly complete confluence, and expressed CD34 and VEGFR-2. Significant proliferative activity, increased migratory capability and forming capillary-like tubules were observed when stimulated with VEGF. The transplanted EPCs in vivo specifically homed to solid tumor tissue and incorporated into the tumor's endothelium. Quantitative analysis revealed that human EPCs contributed significantly to tumor neovascularization by incorporation into tumor vasculature (18.68 +/- 1.32)% of the total vessels. CONCLUSION: EPCs possess the potential to form neovascular network in tumor and play a role in the phenotypical heterogeneity of tumor microvascular architecture.

[Effect of nordy on the function of endothelial progenitor cells from human umbilical cord blood induced by vascular endothelial growth factor].

This study is to investigate whether the synthesized chiral compound Nordy has influence on the function of endothelial progenitor cells (EPCs) from human umbilical cord blood induced by vascular endothelial growth factor (VEGF). EPCs were isolated from human umbilical cord blood by density gradient centrifugation. After cultured for 7 -10 days, EPCs were prepared for detecting effect of Nordy on proliferation, migration and tubule-forming activity in Matrigel induced by VEGF. Incubation of EPCs with 100 micromol L(-1) Nordy for 24 h initially inhibited the proliferative capacity of EPCs induced by VEGF (P <0.05). Moreover, 25 -50 micromol L(-1) Nordy also exhibited inhibitory effect at 48 -72 h. In addition, 25 - 100 micromol L(-1) Nordy impaired EPCs migratory and tubule-forming capacity in vitro (P < 0.05). Nordy could inhibit in EPCs the functions of proliferation, migration and tubulogenesis induced by VEGF in vitro, which might be a possible mechanism of its anti-EPCs effects.

Unique proteomic features induced by a potential antiglioma agent, Nordy (dl-nordihydroguaiaretic acid), in glioma cells.

Nordy is a chirally synthesized compound of a natural lipoxygenase inhibitor nordihydroguaiaretic acid. In this study, we found that Nordy inhibited the growth of human glioma cell lines in vitro and their tumorigenicity in mice. In addition, Nordy promoted differentiation of highly malignant human glioma cells. Investigation into the mechanistic basis of Nordy activities revealed that it altered the pattern of protein expression profiles in tumor cells. By using 2-DE, we found that in human glioma cell lines, at least six proteins were down-regulated after Nordy treatment, while four proteins were elevated in the same cells. Among the six down-regulated proteins, microsequencing with MALDI TOF MS confirmed the identity of five: proliferation-associated gene A (PAG-A), alternative splicing factor-3 (ASF-3), beta-galactoside binding lectin, eukaryotic translation initiation factor 5A (eIF-5A), and coffilin-1 (nonmuscle). Four up-regulated proteins were GST-pi, glyceraldehyde-3-phosphate dehydrogenase, alpha-enolase, and cyclophilin. All these proteins have been reported to participate in key cellular functions including proliferation, metabolism, differentiation, apoptosis, and gene transcription. Our results suggest that Nordy may constitute a promising drug lead for the development of novel antitumor agents targeting proteins that control tumor cell function at multiple levels.

Production of angiogenic factors by human glioblastoma cells following activation of the G-protein coupled formylpeptide receptor FPR.

Activation of the formylpeptide receptor (FPR), a G-protein-coupled receptor, by its chemotactic peptide ligand N-formylmethionyl-leucyl-phenylalanine (fMLF) promotes the directional migration and survival of human glioblastoma cells. fMLF also stimulates glioblastoma cells to produce biologically active VEGF, an important angiogenic factor involved in tumor progression. In this study, we examined the capacity of FPR to regulate the production of another angiogenic factor, the chemokine IL-8 (CXCL8), in addition to its demonstrated ability to induce VEGF secretion by malignant glioma cells. We showed that the human glioblastoma cell line U87 secreted considerable levels of IL-8 (CXCL8) upon stimulation by the FPR agonist peptide fMLF. Tumor cells transfected with small interference (si)RNA targeting FPR failed to produce IL-8 as well as VEGF in response to fMLF. Glioblastoma cells bearing FPR siRNA exhibited reduced rate of tumorigenicity in nude mice and tumors formed by such tumor cells showed less active angiogenesis and lower level expression of both IL-8 and VEGF. These results suggest that FPR plays an important role in the angiogenesis of human malignant gliomas through increasing the production of angiogenic factors by FPR positive tumor cells.

[Detection of interleukin-8 on tissue array of non-small cell lung cancer and its clinicopathological significance].

BACKGROUND: Interleukin-8 (IL-8) is a member of the CXC chemokine family, which involved in tumor growth, metastasis and angiogenesis. The aim of this study is to investigate the expression of IL-8 in non-small cell lung cancer (NSCLC) and its clinicopathologic significance. METHODS: The expression of IL-8 protein and the intratumoral microvessel density (MVD) were detected in 114 cases of NSCLC on tissue array by immunohistochemical method (EnVisionTM method). RESULTS: The positive rate of IL-8 expression was 81.6% (93/114) in 114 cases of the primary lung cancer and 79.1% (34/43) in metastatic lymph nodes respectively. And it was remarkably higher in NSCLC with lymph node metastasis (93.0%, 40/43)) than in those without lymph node metastasis (74.6%, 53/71) (P < 0.05). IL-8 protein expression in primary lung cancer tissues was positively related to TNM stages (P < 0.05), but not to histological type, differentiation degree, age and sex of patients (P > 0.05). In addition, there was significant difference in MVD between IL-8 positive NSCLC tissues (22.1±13.6) and negative ones (14.8±11.2) (P < 0.05). CONCLUSIONS: The present study suggests that there is overexpression of IL-8 in NSCLC, which is closely related to angiogenesis, TNM stages and lymph node metastasis. Detection of IL-8 protein may be helpful to evaluate biological characteristics and therapy for NSCLC.