Isolation and Characterization of Pseudomonas aeruginosa Phages with a Broad Host Spectrum from Hospital Sewage Systems and Their Therapeutic Effect in a Mouse Model.

This study aimed to isolate and characterize phages as an alternative treatment of multidrug- or pan-drug-resistant Pseudomonas aeruginosa. Phage titers and bacterial densities correlated, with the phages disappearing after bacteria were eliminated. We isolated phages in filtered sewage water by a double-layered agar spot test. Fifty-eight P. aeruginosa strains were used to screen the host spectrum of the 14 phages isolated. Random amplification of polymorphic DNA-typing polymerase chain reaction was used to analyze the genomic homologies of the 58 host bacteria strains and four phages with a broad host spectrum. Transmission electron microscopy was used to observe the morphology of the four phages with a broad host spectrum. Mice with intraabdominal P. aeruginosa infection were used as an in vivo animal model to investigate the therapeutic effect of the selected phage. Four virulent phages with a broad host spectrum specific to P. aeruginosa strains were isolated. They were all double-stranded DNA viruses and belonged to four different genotypes. The test curve showed that phage I had the highest adsorption rate, the shortest latent period, and the largest burst size. The infected mouse model indicated that small doses of phage I could prevent the death of infected mice. Phage titers and bacterial densities correlated, with phages disappearing after bacteria were eliminated. Phage I was the most effective and promising treatment of drug-resistant P. aeruginosa.

Epidemic, risk factors of carbapenem-resistant Klebsiella pneumoniae infection and its effect on the early prognosis of liver transplantation.

Background: Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection remains a major cause of morbidity and mortality in early-stage post-liver transplantation (LT). Methods: We retrospectively analyzed the demographic and clinical infections characteristics of all LT recipients in our hospital between January 2019 and December 2021. Results: Among the 272 LT recipients who received LT between January 2019 and December 2021, sixty-two patients had at least one infection within 3-months post-LT, with a prevalence of 22.8% (62/272). The prevalence of CRKP infections was 7.0% (19/272), and the 3-months post-LT mortality was 19.4% (12/62). The risk factors independently related to 3-months mortality were age (Odds ratio (OR)= 1.126, 95% Confidence interval (CI): 1.009~1.257; P=0.034), mechanical ventilation (MV) (OR=1.206, 95% CI: 1.039~1.401; P =0.014), and CRKP infection (OR=18.240, 95% CI: 2.206~150.842; P =0.007). In CRKP infection, the length of ICU stay (OR=1.067, 95% CI: 1.015~1.122; P=0.011), pre-operation infection (POI) (OR=6.733, 95% CI: 1.160~39.088; P=0.034), and hepatocellular carcinoma (HCC) (OR=26.772, 95% CI: 1.747~410.187; P=0.018) were the independent risk factors. With COX multivariate regression analysis, the 3-months survival rate of CRKP infected patients was significantly lower than that without CRKP infection post-LT. Conclusions: CRKP infection is closely correlated with poor prognosis in 3-months post-LT.

The interplay between TGF-ß/SMAD and BMP/SMAD signaling pathways in the epithelial mesenchymal transition of A549 cells induced by silica.

The epithelial-mesenchymal transition (EMT) is a phenotype transdifferentiation of epithelial into mesenchymal cells and contributes to pulmonary fibrotic disease. SMAD-dependent pathway has been reported to play a key role in the multiple fibrotic diseases. We hypothesized that TGF-ß/SMAD signaling could cross-interact with BMP/SMAD signaling pathways in silica-induced EMT in A549 cells. We investigated that the ability of silica-induced EMT in A549 cells, and this process was significantly inhibited by SB431542 through up-regulation of Vimentin, α-SMA and collagen type I expression and down-regulation of E-cadherin expression. Whereas BMP/SMAD inhibition using LDN193189 enhanced EMT. In addition, we also demonstrated that SB431542 could enhance BMP/SMAD signaling pathways in silica-induced EMT and vice versa. Therefore, our study provides evidence that the TGF-ß/SMAD pathway was a crucial regulator in silica-induced EMT and that SB431542 could prevent the EMT. More importantly, we have identified that the interplay of TGF-ß/SMAD and BMP/SMAD pathways in silica-induced EMT in A549 cells.

High-Content Functional Screening of AEG-1 and AKR1C2 for the Promotion of Metastasis in Liver Cancer.

Liver cancer is one of the most lethal cancer types in humans, but our understanding of the molecular mechanisms underlying this process remains insufficient. Here, we conducted high-content screening of the potential genes involved in liver cancer metastasis, which we selected from the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database, based on the SAMcell method and RNA interference technology. We identified two powerful genes in the liver cancer metastasis process, AEG-1 and AKR1C2, both of which proved to be positive regulators in promoting metastasis in liver cancer. Further clinical results verified their roles in liver cancer. In summary, these findings could provide new insight into the liver cancer mechanism and potentially therapeutic novel targets for liver cancer therapies in the future.

BMP-7 attenuated silica-induced pulmonary fibrosis through modulation of the balance between TGF-ß/Smad and BMP-7/Smad signaling pathway.

OBJECTIVE: To investigate the anti-fibrotic effects and possible mechanisms of bone morphogenetic protein-7 (BMP-7) on silica induced fibrosis in RLE-6TN cells, and compare the preventive treatment of experimental silicosis with BMP-7 with therapeutic treatment of silicosis in vitro models. METHODS: RLE-6TN cells were incubated with the supernatant of RAW264.7, treated by 50 µg/mL silica in either presence or absence of BMP-7 in different phases. Morphological changes and the cellular wound-healing assays were used to evaluate the process of EMT. By using Western Blotting, the epithelial marker E-cadherin (E-cad), and the mesenchymal markers Vimentin (Vim), Snail, and fibronectin (FN) were detected as well as the Smad signaling pathway proteins, including phosphorylated Smad1/5(P-Smad1/5), phosphorylated Smad2/3(P-Smad2/3), and non-phosphorylated Smad1, Smad8, and Smad2. The progress of fibrosis was assessed by the content of hydroxyproline (Hyp) and collagen I and III protein levels. In addition, MTT assay was used to explore the toxic effects of silica as well as BMP-7. RESULTS: The EMT model of RLE-6TN cells was established successfully, the cells had a fibroblast-like morphology with increasing migration activity. The expressions of Vim, Snail, FN, collagen I and collagen III were up-regulated with the increase of silica concentration. BMP-7 could attenuate the decrease of P-Smad1/5 and the increase of P-Smad2/3, collagen I, collagen III, and FN via Smad signaling pathway. BMP-7 inhibited the mesenchymal-like responses in RLE-6TN cells, including cell migration, expression of fibrosis markers, and secretion of Hyp. Furthermore, the anti-fibrotic effects in the prevention group were more effective than treatment group. CONCLUSION: The restoration of BMP signaling with BMP-7 is associated with inhibiting silica-induced fibrosis through the mechanisms of activated BMP-7/Smad and suppressed TGF-ß/Smad pathways. Preventive treatment of pulmonary fibrosis progression with BMP-7 may expect to be the optimized strategy than therapeutic therapy of fibrosis.

Sodium tanshinone IIA sulfonate suppresses pulmonary fibroblast proliferation and activation induced by silica: role of the Nrf2/Trx pathway.

Alveolar macrophages are believed to induce oxidative stress via reactive oxygen species (ROS) when silica particles are inhaled. This process can contribute to the pathogenesis of silicosis, but the mechanism is unclear. A traditional Chinese herbal derivative, sodium tanshinone IIA sulfonate (STS), displays significant antioxidant effects. Here, we determine whether STS can attenuate the oxidative stress induced by silica. Traditionally, studies on the toxic effects of silica have focused on monocultures of macrophages or fibroblasts. A coculture model of macrophages (Raw 264.7) and pulmonary fibroblasts (MRC-5) was used in this study to mimic a more in vivo-like environment. We investigated the protective effects of STS on the abnormal proliferation of MRC-5 fibroblasts in an in vitro model. The results showed that fibroblast viability increased with the accumulation of intracellular ROS induced by cocultured Raw 264.7 cells after silica exposure. Treatment with STS markedly ameliorated the silica-induced cell proliferation and oxidative stress. Western blotting and immunofluorescence analysis of the Nrf2 and thioredoxin (Trx) system were conducted, and the results confirmed that treatment with STS enhanced nuclear Nrf2 accumulation and mediated antioxidant Trx system expression. These findings suggest that silica exposure might induce some level of oxidative stress in fibroblasts and that STS might augment antioxidant activities via up-regulation of the Nrf2 and Trx system pathways in MRC-5 cells in vitro.

A Huaier polysaccharide reduced metastasis of human hepatocellular carcinoma SMMC-7721 cells via modulating AUF-1 signaling pathway.

TP-1 is a polysaccharide from one famous fungus Huaier. Treatment with TP-1 significantly inhibited the cell growth, adhesion, migration, and motility of SMMC-7721 cells in a dose-dependent manner. Real-time quantitative RT-PCR revealed a dose-dependent decrease in RNA-binding factor 1 (AUF-1) and astrocyte elevated gene-1 (AEG-1) messenger RNA (mRNA) levels in TP-1-treated SMMC-7721 cells, which is consistent with their protein expression detected by Western blotting. On the contrary, microRNA-122 (miR-122) expression increased in SMMC-7721 cells following TP-1 treatment. Moreover, TP-1 treatment at three doses apparently increased epithelial marker E-cadherin protein expression but decreased the mesenchymal marker N-cadherin protein level. In addition, the hematoxylin-eosin (H & E) staining showed that the TP-1 significantly inhibited the lung metastasis of liver cancer in mice orthotopic implanted with SMMC-7721 tumor tissue. Taken together, these findings proved the inhibitory effect of TP-1 on the growth and metastasis of SMMC-7721 cells, and TP-1 might be offered for future application as a powerful chemopreventive agent against hepatocellular carcinoma (HCC) metastasis.

Effect of bone morphogenic protein-7 on the expression of epithelial-mesenchymal transition markers in silicosis model.

This study presented the effect of bone morphogenic protein-7 (BMP-7) inhibiting epithelial-mesenchymal transition (EMT) in silicosis model. In vivo, Wistar rats were exposed to silica by intratracheal instillation. Seven days later rats were treated with BMP-7. Rats were sacrificed at 15 and 30days after exposure of silica. The results demonstrated vimentin expression was down-regulated; and E-cadherin was up-regulated after intervention with BMP-7. The TGF-ß expression and phosphorylation-p38 were lower in BMP-7 treated group than in silica group. In vitro, p38 MAPK/Snail signaling pathway was involved in the occurrence of EMT in A549 cells treated by silica. EMT was inhibited by BMP-7. The data showed BMP-7 inhibited EMT induced by silica associated with inhibition of p38 MAPK/Snail pathway.

A Huaier polysaccharide restrains hepatocellular carcinoma growth and metastasis by suppression angiogenesis.

Hepatocellular carcinoma (HCC) is a highly metastatic cancer. Huaier polysaccharide (TP-1) is a naturally occurring bioactive macromolecule, found in Huaier fungus and has been shown to exert in vitro antitumor and antimetastasis for HCC, but no study has addressed in vivo efficacy and mechanisms of action. Presently, we found that TP-1 at doses of 0.5, 1 and 2mg/kg significantly inhibited tumor growth and metastasis to the lung in mice bearing HCC SMMC-7721 tumors without toxicity. The analysis of tumors by immunohistochemistry demonstrated that TP-1 inhibited PCNA expression, increased the number of TUNEL-positive cells and reduced microvessel density (MVD) to achieve this effect. Furthermore, TP-1 administration reduced the protein expression of hypoxia-inducible factor (HIF)-1alpha, vascular endothelial growth factor (VEGF), AUF-1 and AEG-1, in tumor tissues. Taken together, our data suggested that the antitumor and anti-metastatic activities of TP-1 might be at least partially through down-regulation of HIF-1alpha/VEGF and AUF-1/AEG-1 signaling pathways.

A Huaier polysaccharide inhibits hepatocellular carcinoma growth and metastasis.

This study was carried out to evaluate the effects of a Huaier polysaccharide (TP-1) on the tumor growth and immune function in hepatocellular carcinoma (HCC) H22-based mouse in vivo. Results showed that TP-1 was capable of repressing transplanted H22 solid hepatic tumor cell growth in vivo, prolonging the live time of mice bearing ascetic H22 tumors, and repressing the pulmonary metastasis of H22-bearing mice. Moreover, the relative weight of immune organ (spleen and thymus) and lymphocyte proliferation were improved after TP-1 treatment. Furthermore, the treatment with TP-1 could promote immune-stimulating serum cytokines, such as IL-2 and IFN-γ, but inhibit immune-suppressing serum cytokines IL-10 secretion in H22-bearing mice. Besides, the percentage of CD4+ T cells and NK cells was increased, whereas the number of CD8+ T cells decreased in tumor-bearing mice following TP-1 administration. In addition, this compound displayed little toxic effects to major organ of tumor-bearing mice at the therapeutic dose, such as the liver and kidney. This experimental finding suggested that TP-1 exhibited prominent antitumor activities in vivo via enhancement of host immune system function in H22 tumor-bearing mice. This product could be developed individually as a safe and potent biological response modifier for HCC therapy.

Long non-coding RNA NR_045623 and NR_028291 involved in benzene hematotoxicity in occupationally benzene-exposed workers.

Benzene is an established human hematotoxicant and leukemogen. New insights into the pathogenesis of benzene hematotoxicity are urgently needed. Long non-coding RNA (lncRNA) widely participate in various physiological and pathological processes. It has been shown that lncRNA plays an important role in hematologic malignancy tumorigenesis. However, the expression and biological function of lncRNA during benzene hematotoxicity progress remain largely unknown. An integrated analysis of differentially expressed lncRNA and mRNA was performed to identify genes which were likely to be critical for benzene hematotoxicity through Microarray analysis. Dynamic gene network analysis of the differentially expressed lncRNA and mRNA was constructed and two main lncRNA (NR_045623 and NR_028291) were discovered and two key lncRNA subnets were involved in immune responses, hematopoiesis, B cell receptor signaling pathway and chronic myeloid leukemia. These findings suggested that NR_045623 and NR_028291 might be the key genes associated with benzene hematotoxicity.

AEG-1 Promotes Metastasis Through Downstream AKR1C2 and NF1 in Liver Cancer.

Liver cancer is one of the most lethal cancers, but our knowledge of the molecular mechanism underlying this process remains insufficient. Through deep sequencing and expression regulation analysis in liver cancer cells, we identified two novel factors, AKR1C2 (positive factor) and NF1 (negative factor), as the AEG-1 downstream players in the process of metastasis in liver cancer. They were experimentally validated to have the capacities of regulating cell migration, cell invasion, cell proliferation, and EMT. Further clinic expression and animal model evidence confirmed their functions. Together, our findings provide a new insight into the pharmaceutical and therapeutic use of AEG-1 and downstream AKR1C2 and NF1.

Differential gene expression profiling analysis in workers occupationally exposed to benzene.

UNLABELLED: Benzene is an important industrial chemical and an environmental contaminant, but the pathogenesis of hematotoxicity induced by chronic occupational benzene exposure remains to be elucidated. To gain an insight into the molecular mechanisms and new biomarkers, microarray analysis was used to identify the differentially expressed mRNA critical for benzene hematotoxicity. RNA was extracted from four chronic benzene poisoning patients occupationally exposed to benzene, three benzene-exposed workers without clinical symptoms and three health controls without benzene exposure and mRNA expression profiling was performed using Gene Chip Human Gene 2.0ST Arrays. Analysis of mRNA expression profiles were conducted to identify key genes, biological processes and pathways by the series test of cluster (STC), STC-Gene Ontology analysis (STC-GO), pathway analysis and Signal-net. PRINCIPAL FINDINGS: 1) 1661 differentially expressed mRNAs were identified and assigned to sixteen model profiles. 2) Profiles 14, 10, 11, 1 and 15 are the predominant expression profiles which were involved in immune response, inflammatory response, chemotaxis, defense response, anti-apoptosis and signal transduction. 3) The importance of immune response at benzene hematotoxicity is highlighted by several immune-related signaling pathways such as B/T cell receptor signaling pathway, acute myeloid leukemia, hematopoietic cell lineage and natural killer cell mediated cytotoxicity. 4) Signet analysis showed that PIK3R1, PIK3CG, PIK3R2, GNAI3, KRAS, NRAS, NFKB1, HLA-DMA, and HLA-DMB were key genes involved in benzene hematotoxicity. These genes might be new biomarkers for the prevention and early diagnosis of benzene poisoning. This is a preliminary study that paves the way to further functional study to understand the underlying regulatory mechanisms.

Suppression of thioredoxin system contributes to silica-induced oxidative stress and pulmonary fibrogenesis in rats.

Silicosis is one of the most prevalent occupational lung diseases worldwide. This study aimed to investigate the possible mechanism that silica affected thioredoxin (Trx) system during the development of silicosis in vivo. Male Wistar rats were randomly divided into saline group and silica group in which rats were intratracheally instilled with a single dose of silica suspension (50mg in 1ml saline/rat). After 7, 15 or 30 days instillation, rats were sacrificed. Biochemical parameters and histopathology were assessed. Our results demonstrated that silica could significantly cause the accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA) as well as activate antioxidative protein Nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream protein Trx in the early exposure to silica. The inhibition of Trx activity and the down-regulated expression of thioredoxin reductase (TrxR), suggesting that the function of Trx system may be suppressive induced by silica. Content of lung hydroxyproline and histopathological results showed significant fibrosis development with time. In conclusion, our study demonstrated that silica could suppress the Trx system to perturb the redox balance, elicit oxidative stress, and eventually induce pulmonary fibrosis.

Bone morphogenetic protein-7 inhibits silica-induced pulmonary fibrosis in rats.

Bone morphogenetic protein-7 (BMP-7) has been shown to inhibit liver and renal fibrosis in in vivo and vitro studies. There is no study to investigate BMP-7's role in the development of pulmonary fibrosis induced by silica. In the current study, we used the rat model to explore the potential antifibrotic role of BMP-7 and its underlying mechanism in silica-induced pulmonary fibrosis. Sixty Wistar rats were randomly assigned into three groups. Control group received saline, silica group received silica and BMP-7 treated group received silica and BMP-7. BMP-7 was administered to silica-treated rats intraperitoneally at a dose of 300µg/kg/injection from day 8 to day 30 every other day. After the animals were sacrificed on day 15 and 30, hydroxyproline levels, the protein expressions of BMP/Smad and TGF-ß/Smad signaling, and histopathology in lung tissues were analyzed. The hydroxyproline contents in BMP-7 treated groups were significantly lower than the silica groups (P<0.05). Histopathological results showed BMP-7 could reduce the progression of silica induced fibrosis. Furthermore, the expression of p-Smad1/5/8, a marker of BMP/Smad signaling, was significantly up-regulated in BMP-7 treated groups (P<0.05) compared with the silica groups. On the contrary, the expression of p-Smad2/3, a marker for TGF-ß/Smad signaling, reduced significantly in BMP-7-treated groups compared with silica groups (P<0.05). In conclusion, the pulmonary fibrosis induced by silica in rats was significantly reduced with the therapeutic treatment of BMP-7. The antifibrotic effect of BMP-7 could be related to the activation of BMP/Smad signaling and inhibition of TGF-ß/Smad pathways.