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MMP9 Processing of HSPB1 Regulates Tumor Progression
Matrix metalloproteinases regulate pathophysiological events by processing matrix proteins and secreted proteins. Previously, we demonstrated that soluble heat shock protein B1 (HSPB1) is released primarily from endothelial cells (ECs) and regulates angiogenesis via direct interaction with vascular endothelial growth factor (VEGF). Here we report that MMP9 can cleave HSPB1 and release anti-angiogenic fragments, which play a key role in tumorprogression. We mapped the cleavage sites and explored their physiological relevance during these processing events. HSPB1 cleavage by MMP9 inhibited VEGF-induced ECs activation and the C-terminal HSPB1 fragment exhibited more interaction with VEGF than did full-length HSPB1. HSPB1 cleavage occurs during B16F10 lung progression in wild-type mice. Also, intact HSPB1 was more detected on tumor endothelium of MMP9 null mice than wild type mice. Finally, we confirmed that secretion of C-terminal HSPB1 fragment was significantly inhibited lung and liver tumor progression of B16F10 melanoma cells and lung tumor progression of CT26 colon carcinoma cells, compared to full-length HSPB1. These data suggest that in vivo MMP9-mediated processing of HSPB1 acts to regulate VEGF-induced ECs activation for tumor progression, releasing anti-angiogenic HSPB1 fragments. Moreover, these findings potentially explain an anti-target effect for the failure of MMP inhibitors in clinical trials, suggesting that MMP inhibitors may have pro-tumorigenic effects by reducing HSPB1 fragmentation
Performance of the tuberculin skin test and interferon-γ release assay for detection of tuberculosis infection in immunocompromised patients in a BCG-vaccinated population
<p>Abstract</p> <p>Background</p> <p>Interferon-γ release assay (IGRA) may improve diagnostic accuracy for latent tuberculosis infection (LTBI). This study compared the performance of the tuberculin skin test (TST) with that of IGRA for the diagnosis of LTBI in immunocompromised patients in an intermediate TB burden country where BCG vaccination is mandatory.</p> <p>Methods</p> <p>We conducted a retrospective observational study of patients given the TST and an IGRA, the QuantiFERON-TB Gold In-Tube (QFT-IT), at Severance Hospital, a tertiary hospital in South Korea, from December 2006 to May 2009.</p> <p>Results</p> <p>Of 211 patients who underwent TST and QFT-IT testing, 117 (55%) were classified as immunocompromised. Significantly fewer immunocompromised than immunocompetent patients had positive TST results (10.3% vs. 27.7%, p 0.001), whereas the percentage of positive QFT-IT results was comparable for both groups (21.4% vs. 25.5%). However, indeterminate QFT-IT results were more frequent in immunocompromised than immunocompetent patients (21.4% vs. 9.6%, p 0.021). Agreement between the TST and QFT-IT was fair for the immunocompromised group (κ = 0.38), but moderate agreement was observed for the immunocompetent group (κ = 0.57). Indeterminate QFT-IT results were associated with anaemia, lymphocytopenia, hypoproteinemia, and hypoalbuminemia.</p> <p>Conclusion</p> <p>In immunocompromised patients, the QFT-IT may be more sensitive than the TST for detection of LTBI, but it resulted in a considerable proportion of indeterminate results. Therefore, both tests may maximise the efficacy of screening for LTBI in immunocompromised patients.</p
Systematic identification of an integrative network module during senescence from time-series gene expression
Background: Cellular senescence irreversibly arrests growth of human diploid cells. In addition, recent studies have indicated that senescence is a multi-step evolving process related to important complex biological processes. Most studies analyzed only the genes and their functions representing each senescence phase without considering gene-level interactions and continuously perturbed genes. It is necessary to reveal the genotypic mechanism inferred by affected genes and their interaction underlying the senescence process. Results: We suggested a novel computational approach to identify an integrative network which profiles an underlying genotypic signature from time-series gene expression data. The relatively perturbed genes were selected for each time point based on the proposed scoring measure denominated as perturbation scores. Then, the selected genes were integrated with protein-protein interactions to construct time point specific network. From these constructed networks, the conserved edges across time point were extracted for the common network and statistical test was performed to demonstrate that the network could explain the phenotypic alteration. As a result, it was confirmed that the difference of average perturbation scores of common networks at both two time points could explain the phenotypic alteration. We also performed functional enrichment on the common network and identified high association with phenotypic alteration. Remarkably, we observed that the identified cell cycle specific common network played an important role in replicative senescence as a key regulator. Conclusions: Heretofore, the network analysis from time series gene expression data has been focused on what topological structure was changed over time point. Conversely, we focused on the conserved structure but its context was changed in course of time and showed it was available to explain the phenotypic changes. We expect that the proposed method will help to elucidate the biological mechanism unrevealed by the existing approaches.1
High dose therapy followed by autologous peripheral blood stem cell transplantation as a first line treatment for multiple myeloma: a Korean Multicenter Study.
We conducted a phase II multicenter trial to estimate the response and survival of patients with newly diagnosed multiple myeloma to high dose melphalan therapy followed by autologous peripheral blood stem cell transplantation. Eligible patients who had undergone induction with vincristine, adriamycin and dexamethasone (VAD) should have adequate cardiac, pulmonary and renal function (creatinine <2 mg/dL). Melphalan at 200 mg/m2 was used as a conditioning regimen. Eighty patients were enrolled from 13 centers. The median age of the patients was 53 yr (range; 20 to 68 yr). The initial stage was IA/IIA/IIB/IIIA/IIIB in 3/8/1/54/14 patients, respectively. Beta2-microglobulin, CRP and LDH were increased in 74, 42 and 34% of the patients examined. Cytogenetic data were available in 30 patients, and 6 patients showed numeric or structural abnormalities. Two therapy-related mortalities occurred from infection. Among the 78 evaluable patients, CR/PR/MR/NC/PD were achieved in 48/26/2/1/1 patients, respectively. After a median follow-up of 30 months, the median overall and event-free survivals were 66 months (95% CI: 20-112) and 24 months (95% CI: 18-29), respectively. This study verifies the efficacy and feasibility of high dose melphalan therapy with autologous stem cell transplantation in newly diagnosed multiple myeloma
Comparison of sampling methods in assessing the microbiome from patients with ulcerative colitis
Background
Dysbiosis of ulcerative colitis (UC) has been frequently investigated using readily accessible stool samples. However, stool samples might insufficiently represent the mucosa-associated microbiome status. We hypothesized that luminal contents including loosely adherent luminal bacteria after bowel preparation may be suitable for diagnosing the dysbiosis of UC.
Methods
This study included 16 patients with UC (9 men and 7 women, mean age: 52.13 ± 14.09 years) and 15 sex- and age-matched healthy individuals (8 men and 7 women, mean age: 50.93 ± 14.11 years). They donated stool samples before colonoscopy and underwent luminal content aspiration and endoscopic biopsy during the colonoscopy. Then, the composition of each microbiome sample was analyzed by 16S rRNA-based next-generation sequencing.
Results
The microbiome between stool, luminal contents, and biopsy was significantly different in alpha and beta diversities. However, a correlation existed between stool and luminal contents in the Procrustes test (p = 0.001) and Mantel test (p = 0.0001). The stool microbiome was different between patients with UC and the healthy controls. Conversely, no difference was found in the microbiome of luminal content and biopsy samples between the two subject groups. The microbiome of stool and lavage predicted UC, with AUC values of 0.85 and 0.81, respectively.
Conclusion
The microbiome of stool, luminal contents, and biopsy was significantly different. However, the microbiome of luminal contents during colonoscopy can predict UC, with AUC values of 0.81. Colonoscopic luminal content aspiration analysis could determine microbiome differences between patients with UC and the healthy control, thereby beneficial in screening dysbiosis via endoscopy.
Trial registration: This trial was registered at
http://cris.nih.go.kr
. Registration No.: KCT0003352), Date: 2018–11-13.This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT) (No. 2020R1G1A100923411)
Liver transplantation for acute-on-chronic liver failure from erythropoietic protoporphyria
Erythropoietic protoporphyria (EPP) is an inherited disorder of the heme metabolic pathway that is characterized by accumulation of protoporphyrin in the blood, erythrocytes, and tissues, and cutaneous manifestations of photosensitivity, all resulting from abnormalities in ferrochelatase (FECH) activity due to mutations in the FECH gene. Protoporphyrin is excreted by the liver, and excess protoporphyrin leads to cholelithiasis with obstructive episodes and chronic liver disease, finally progressing to liver cirrhosis. Patients with end-stage EPP-associated liver disease require liver transplantation. We describe here a 31-year-old male patient with EPP who experienced acute-on-chronic liver failure and underwent deceased-donor liver transplantation. Surgical and postoperative care included specific shielding from exposure to ultraviolet radiation to prevent photosensitivity-associated adverse effects. The patient recovered uneventfully and was doing well 24 months after transplantation. Future prevention and treatment of liver disease are discussed in detail
Inhibitory effects of Enteromorpha prolifera on the production of nitric oxide, prostaglandin E2, and pro-inflammatory cytokines in RAW 264.7 cells
Inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 have been used as tools for the screening of anti-inflammatory agents. In a search for inhibitors of COX-2 and iNOS, we found that extracts of Enteromorpha prolifera inhibit the production of nitric oxide (NO) and prostaglandin (PG)E2 in LPS-stimulated RAW 264.7 macrophage cells. We first extracted E. prolifera with 80% ethanol and the extract was partitioned with hexane, dichloromethane, ethyl acetate, butanol, and water, successively. The results indicate that the hexane and ethyl acetate fractions effective inhibited LPS-induced NO and PGE2 production in RAW 264.7 cells. To test the inhibition effects of the E. prolifera fractions on other cytokines, we also performed an ELISA assay on tumor necrosis factor (TNF)-α, IL-1β, and IL-6 in LPS-stimulated RAW 264.7 macrophage cells. The expression of TNF-α, IL-1β, and IL-6 was also decreased following treatment with the hexane and ethyl acetate fractions. To test the potential application of the E. prolifera extract as a cosmetic material, we also performed MTT assays on keratinocyte HaCaT cells as well as primary skin irritation tests. In these assays, the E. prolifera extracts did not induce any adverse reactions. Based on these results, we suggest that E. prolifera extracts may be considered potential anti-inflammatory candidates for skin health.Colegio de Farmacéuticos de la Provincia de Buenos Aire
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