p38-mediated FOXN3 phosphorylation modulates lung inflammation and injury through the NF-κB signaling pathway.

NF-κB activates the primary inflammatory response pathway responsible for methicillin-resistant Staphylococcus aureus (MRSA)-induced lung inflammation and injury. Here, we report that the Forkhead box transcription factor FOXN3 ameliorates MRSA-induced pulmonary inflammatory injury by inactivating NF-κB signaling. FOXN3 competes with IκBα for binding to heterogeneous ribonucleoprotein-U (hnRNPU), thereby blocking ß-TrCP-mediated IκBα degradation and leading to NF-κB inactivation. FOXN3 is directly phosphorylated by p38 at S83 and S85 residues, which induces its dissociation from hnRNPU, thus promoting NF-κB activation. After dissociation, the phosphorylated FOXN3 becomes unstable and undergoes proteasomal degradation. Additionally, hnRNPU is essential for p38-mediated FOXN3 phosphorylation and subsequent phosphorylation-dependent degradation. Functionally, genetic ablation of FOXN3 phosphorylation results in strong resistance to MRSA-induced pulmonary inflammatory injury. Importantly, FOXN3 phosphorylation is clinically positively correlated with pulmonary inflammatory disorders. This study uncovers a previously unknown regulatory mechanism underpinning the indispensable role of FOXN3 phosphorylation in the inflammatory response to pulmonary infection.

Enhanced therapeutic potential of Flotillins-modified MenSCs by improve the survival, proliferation and migration.

Menstrual blood-derived endometrial stem cells (MenSCs) have attracted increasing interest due to their excellent safety, and lack of ethical dilemma as well as their ability to be periodically obtained in a noninvasive manner. However, although preclinical research as shown the therapeutic potential of MenSCs in several diseases, their poor cell survival and low engraftment at disease sites reduce their clinical efficacy. Flotillins (including Flot1 and Flot2) are implicated in various cellular processes, such as vesicular trafficking, signal transduction, cell proliferation, migration and apoptosis. In this study, we aimed to determine the effects of Flotillins on MenSCs survival, proliferation and migration. Our experimental results show that MenSCs were modified to overexpress Flot1 and/or Flot2 without altering their intrinsic characteristics. Flot1 and Flot2 co-overexpression promoted MenSC viability and proliferation capacity. Moreover, Flot1 or Flot2 overexpression significantly promoted the migration and inhibited the apoptosis of MenSCs compared with the negative control group, and these effects were stronger in the Flot1 and Flot2 gene co-overexpression group. However, these effects were significantly reversed after Flot1 and/or Flot2 knockdown. In conclusion, our results indicate that Flot1 and Flot2 overexpression in MenSCs improved their proliferation and migration and inhibited their apoptosis, and this might be an effective approach to improve the efficiency of cell-based therapies.

Extracellular vesicle-transmitted miR-671-5p alleviates lung inflammation and injury by regulating the AAK1/NF-κB axis.

Mesenchymal stem cells regulate remote intercellular signaling communication via their secreted extracellular vesicles. Here, we report that menstrual blood-derived stem cells alleviate acute lung inflammation and injury via their extracellular vesicle-transmitted miR-671-5p. Disruption of this abundantly expressed miR-671-5p dramatically reduced the ameliorative effect of extracellular vesicles released by menstrual blood-derived stem cells on lipopolysaccharide (LPS)-induced pulmonary inflammatory injury. Mechanistically, miR-671-5p directly targets the kinase AAK1 for post-transcriptional degradation. AAK1 is found to positively regulate the activation of nuclear factor κB (NF-κB) signaling by controlling the stability of the inhibitory protein IκBα. This study identifies a potential molecular basis of how extracellular vesicles derived from mesenchymal stem cells improve pulmonary inflammatory injury and highlights the functional importance of the miR-671-5p/AAK1 axis in the progression of pulmonary inflammatory diseases. More importantly, this study provides a promising cell-based approach for the treatment of pulmonary inflammatory disorders through an extracellular vesicle-dependent pathway.

Knockout of PERK protects rat Müller glial cells against OGD-induced endoplasmic reticulum stress-related apoptosis.

BACKGROUND: The pathological basis for many retinal diseases, retinal ischemia is also one of the most common causes of visual impairment. Numerous ocular diseases have been linked to Endoplasmic reticulum(ER)stress. However, there is still no clear understanding of the relationship between ER stress and Müller glial cells during retinal ischemia and hypoxia. This study examined the effects of ER stress on autophagy and apoptosis-related proteins, as well as the microtubule-related protein tau in rMC-1 cells. METHODS: rMC-1 cells were cultured in vitro. RT-PCR、immunofluorescence and Western blotting revealed the expression levels of associated mRNAs and proteins, and the CCK-8 and flow cytometry assays detected cell apoptosis. RESULTS: The results showed that under OGD(Oxygen-glucose deprivation) conditions, the number of rMC-1 cells was decreased, the PERK/eIF2a pathway was activated, and the expressions of p-tau, LC3、Beclin1 and Caspase-12 proteins were increased. After the PERK knockout, the expression of the above proteins was decreased, and the apoptosis was also decreased. CONCLUSION: According to the findings of this study, specific downregulation of PERK expression had an anti-apoptotic effect on OGD-conditioned rMC-1 cells. There is a possibility that this is one of the mechanisms of MG cell apoptosis during retinal ischemic injury.

The m6A methyltransferase METTL3 cooperates with demethylase ALKBH5 to regulate osteogenic differentiation through NF-κB signaling.

As a m6A methylation modifier, METTL3 is functionally involved in various biological processes. Nevertheless, the role of METTL3 in osteogenesis is not determined up to date. In the current study, METTL3 is identified as a crucial regulator in the progression of osteogenic differentiation. Loss of METTL3 significantly augments calcium deposition and enhances alkaline phosphatase activity of mesenchymal stem cells, uncovering an inhibitory role of METTL3 in osteogenesis. More importantly, the underlying molecular basis by which METTL3 regulates osteogenesis is illustrated. We find that METTL3 positively regulates expression of MYD88, a critical upstream regulator of NF-κB signaling, by facilitating m6A methylation modification to MYD88-RNA, subsequently inducing the activation of NF-κB which is widely regarded as a repressor of osteogenesis and therefore suppressing osteogenic progression. Moreover, the METTL3-mediated m6A methylation is found to be dynamically reversed by the demethylase ALKBH5. In summary, this study highlights the functional importance of METTL3 in osteogenic differentiation and METTL3 may serve as a promising molecular target in regenerative medicine, as well as in the field of bone tissue engineering.

LncRNA NKILA regulates endothelium inflammation by controlling a NF-κB/KLF4 positive feedback loop.

Endothelium inflammation, a key event in vascular pathological process, can lead to endothelial activation and subsequent vascular disorders. Long non-coding RNA NKILA plays an important regulatory role in pro-inflammatory response. However, the underlying molecular basis by which NKILA regulates endothelial inflammation is poorly understood. In this study, we identify NKILA as a critical repressor to protect the endothelium from inflammation. Mechanistically, we show that NKILA is able to positively mediate the expression of KLF4, an anti-inflammatory atheroprotective regulator in endothelial cells (ECs), by a NF-κB-mediated DNA methylation mechanism. Moreover, NF-κB is found to help recruit DNMT3A to the CpG island of KLF4 promoter, facilitating KLF4 promoter DNA methylation and transcriptional repression. More importantly, we find KLF4 can inversely attenuate NF-κB transcriptional activity via establishing a NF-κB/KLF4 positive feedback loop, which is under the control of NKILA. Hence, sustained endothelium inflammation will occur, once the NKILA becomes dysfunctional. These studies revealed that NKILA can function as a vital regulator to protect the endothelium from inflammatory lesions and related vascular diseases.

LncRNA HOXA-AS2 positively regulates osteogenesis of mesenchymal stem cells through inactivating NF-κB signalling.

As is previously reported, mesenchymal stem cells have potential ability to differentiate into osteocytes. However, the underlying mechanism during this biological process is poorly understood. In the present study, we identify a novel long non-coding RNA named HOXA-AS2 as a critical regulator during the formation of osteogenesis. Attenuation of HOXA-AS2 can reduce the calcium deposition and repress the alkaline phosphatase activity. Moreover, the expressions of osteogenic marker genes are markedly downregulated after HOXA-AS2 depletion. Mechanistically, we found HOXA-AS2 can regulate the transcriptional activity of NF-κB, a critical inhibitor of osteogenesis. More importantly, HOXA-AS2 knockdown could result in the transcriptional repression of the osteogenic master transcription factor SP7 by a NF-κB/HDAC2-coordinated H3K27 deacetylation mechanism. Based on these studies, we conclude that HOXA-AS2 may serve as a promising therapeutic target for bone tissue repair and regeneration in the near future.

IMM-H007, a novel small molecule inhibitor for atherosclerosis, represses endothelium inflammation by regulating the activity of NF-κB and JNK/AP1 signaling.

Endothelium inflammation has become a major risk factor for pathological development of atherosclerosis. IMM-H007 (H007), a small molecule compound, is previously reported to reduce inflammatory atherosclerosis. However, the regulatory role of H007 in endothelium inflammation is still unclear. Here, we characterize H007 as a critical repressor in regulation of endothelium inflammation. We find that H007 significantly inhibits monocyte adhesion to endothelial cells and its transendothelial migration. Mechanistically, H007 markedly represses TNFα-induced IκBα degradation and NF-κB nuclear translocation, therefore leading to NF-κB-mediated inflammatory suppression. Moreover, another inflammatory signaling JNK/c-Jun, which is always co-activated with NF-κB in response to pro-inflammatory stimuli, is also found to be restrained by H007 through reducing its phosphorylation status. Thus, we conclude that H007 negatively regulates endothelium inflammation through inactivating NF-κB and JNK/AP1 signaling. More importantly, this study provides us a new insight into understanding the molecular basis by which H007 regulates inflammatory atherosclerosis.

The T cell activating properties and antitumour activity of Staphylococcal Enterotoxin-like Q.

Staphylococcal enterotoxins (SEs), as typical superantigens, exhibit promising antitumour activity in the clinic, but their unavoidable side effects related to fever and emesis seriously limit their application for the treatment of malignant tumours. Fortunately, the identification of Staphylococcal enterotoxin-like toxins (SEls), which possess amino acid sequences similar to those of classical SEs but exhibit no or low emetic activity, has provided a set of potential immunomodulatory candidates for cancer therapy. The aim of this study was to examine the effect of SElQ on lymphocyte activation and to further demonstrate its antitumour activity both in vitro and in vivo. High-purity SElQ was successfully harvested, and in vitro results confirmed that SElQ can significantly activate mouse- and human-derived lymphocytes in a dose-dependent manner, particularly CD4+ and CD8+ T cells, which showed significant increases in both percentage and absolute number. Further examination revealed that in addition to the originally recognized TCR Vß5 and 21, TCR Vß14, 17 and 18 were activated in SElQ-induced human PBMCs. Moreover, the expression of IL-2 and IFN-γ was significantly upregulated in vitro and in vivo after SElQ treatment. Based on the findings that SElQ induces lymphocyte activation and cytokine release, we then confirmed its antitumour activity both in vitro and in vivo. The data showed that treatment with a low concentration of SElQ (30 µg/mouse) could inhibit the growth of tumours by approximately 30% and no significant toxicity was observed. Taken together, our results demonstrated that SElQ can significantly induce T cell activation and cytokine release and further elicit substantial antitumour activity and thus provide support for the potential application of SElQ in cancer immunotherapy.

Correction to: CBFA2T2 is associated with a cancer stem cell state in renal cell carcinoma.

[This corrects the article DOI: 10.1186/s12935-017-0473-z.].

Multiple P-TEFbs cooperatively regulate the release of promoter-proximally paused RNA polymerase II.

The association of DSIF and NELF with initiated RNA Polymerase II (Pol II) is the general mechanism for inducing promoter-proximal pausing of Pol II. However, it remains largely unclear how the paused Pol II is released in response to stimulation. Here, we show that the release of the paused Pol II is cooperatively regulated by multiple P-TEFbs which are recruited by bromodomain-containing protein Brd4 and super elongation complex (SEC) via different recruitment mechanisms. Upon stimulation, Brd4 recruits P-TEFb to Spt5/DSIF via a recruitment pathway consisting of Med1, Med23 and Tat-SF1, whereas SEC recruits P-TEFb to NELF-A and NELF-E via Paf1c and Med26, respectively. P-TEFb-mediated phosphorylation of Spt5, NELF-A and NELF-E results in the dissociation of NELF from Pol II, thereby transiting transcription from pausing to elongation. Additionally, we demonstrate that P-TEFb-mediated Ser2 phosphorylation of Pol II is dispensable for pause release. Therefore, our studies reveal a co-regulatory mechanism of Brd4 and SEC in modulating the transcriptional pause release by recruiting multiple P-TEFbs via a Mediator- and Paf1c-coordinated recruitment network.

CBFA2T2 is associated with a cancer stem cell state in renal cell carcinoma.

BACKGROUND: Renal cell carcinoma (RCC) is the most common kidney cancer, accounting for approximately 80-90% of all primary kidney cancer. Treatment for patients with advanced RCC remains unsatisfactory. Rare cancer stem cells (CSCs) are proposed to be responsible for failure of current treatment. METHODS: OncoLnc was used as a tool for interactively exploring survival correlations. Gene manipulation and expression analysis were carried out using siRNA, RT-PCR and Western blotting. Wound healing and invasion assays were used for phenotypical characterization. Aldefluor assay and FACS sorting Sphere culture were used to determine the "stemness" of CSCs. Co-Immunoprecipitation (Co-IP) was used to examine the interaction between OCT4 and CBFA2T2. Student's t-test and Chi square test was used to analyze statistical significance. RESULTS: CBFA2T2 expression can significantly predict the survival of RCC patients. Knocking-down of CBFA2T2 can inhibit cell migration and invasion in RCC cells in vitro, and reduce ALDHhigh CSCs populations. CBFA2T2 expression is necessary for sphere-forming ability and cancer stem cells marker expression in RCC cell lines. CONCLUSIONS: Our data suggest that CBFA2T2 expression correlates with aggressive characteristics of RCC and CBFA2T2 is required for maintenance of "stemness" through regulation of stem cells factors, thereby highlighting CBFA2T2 as a potential therapeutic target for RCC treatment.

Carcinogenic ability quantification of human papilloma virus subtypes in eastern China.

Human papilloma virus (HPV) infection is a precursor of cervical cancer. This study aimed to introduce a method to quantify the risk of cervical cancer resulting from infection by different HPV subtypes, to help guide patient treatment. Nucleic acid molecule flow-through hybridization and gene chip technology were used to test 6,510 non-cervical cancer healthy volunteers (≤CIN-I) and 204 cervical cancer patients (≥CIN-III) from Dongying City for 21 HPV subtypes (HPV-16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 68, 6, 11, 42, 43, 44, 53, 66 and CP8304) in exfoliated cervical cells. The positive proportion of HPV subtypes was calculated, excluding or including patients with multiple subtype infections. The lower (L) and upper (H) limits of the carcinogenic risk score range were calculated, respectively. The values of carcinogenic index ± uncertainty in the carcinogenic ability (CI ± U) were also calculated. CI = (H + L)/2 represents the carcinogenic risk of the different subtypes, and U =(H - L)/2 represents the probability of each subtype being present in multiple infections. Infection rates were 15.87 and 96.57%, and HPV subtypes with high infection rates were HPV-16, 52, 58, 33, 18, and 31 and HPV-16, 31, 58, 18, 68, and 33 in the non-cervical cancer and cervical cancer groups, respectively. HPV subtypes with high risk of cervical cancer were HPV-31 (3.71 ± 0.68), 51 (2.65 ± 0.44), 18 (2.03 ± 0.43), 68 (1.76 ± 0.40), 58 (1.68 ± 0.49), and 16 (1.39 ± 0.33). We have provided a quantitative method for expressing HPV subtype carcinogenic risk.

miR-328-5p functions as a critical negative regulator in early endothelial inflammation and advanced atherosclerosis.

Early proatherogenic inflammation constitutes a significant risk factor for atherogenesis development. Despite this, the precise molecular mechanisms driving this pathological progression largely remain elusive. Our study unveils a pivotal role for the microRNA miR-328-5p in dampening endothelial inflammation by modulating the stability of JUNB (JunB proto-oncogene). Perturbation of miR-328-5p levels results in heightened monocyte adhesion to endothelial cells and enhanced transendothelial migration, while its overexpression mitigates these inflammatory processes. Furthermore, miR-328-5p hinders macrophage polarization toward the pro-inflammatory M1 phenotype, and exerts a negative influence on atherosclerotic plaque formation in vivo. By pinpointing JUNB as a direct miR-328-5p target, our research underscores the potential of miR-328-5p as a therapeutic target for inflammatory atherosclerosis. Reintroduction of JUNB effectively counteracts the anti-atherosclerotic effects of miR-328-5p, highlighting the promise of pharmacological miR-328-5p targeting in managing inflammatory atherosclerosis.

Bone marrow-derived mesenchymal stem cells: A promising therapeutic option for the treatment of diabetic foot ulcers.

Chronic wounds fail to heal through the three normal stages of healing (inflammatory, proliferative, and remodelling), resulting in a chronic tissue injury that is not repaired within the average time limit. Patients suffering from type 1 and type 2 diabetes are prone to develop diabetic foot ulcers (DFUs), which commonly develop into chronic wounds that are non treatable with conventional therapies. DFU develops due to various risk factors, such as peripheral neuropathy, peripheral vascular disease, arterial insufficiency, foot deformities, trauma and impaired resistance to infection. DFUs have gradually become a major problem in the health care system worldwide. In this review, we not only focus on the pathogenesis of DFU but also comprehensively summarize the outcomes of preclinical and clinical studies thus far and the potential therapeutic mechanism of bone marrow-derived mesenchymal stem cells (BMSCs) for the treatment of DFU. Based on the published results, BMSC transplantation can contribute to wound healing through growth factor secretion, anti-inflammation, differentiation into tissue-specific cells, neovascularization, re-epithelialization and angiogenesis in DFUs. Moreover, clinical trials showed that BMSC treatment in patients with diabetic ulcers improved ulcer healing and the ankle-brachial index, ameliorated pain scores, and enhanced claudication walking distances with no reported complications. In conclusion, although BMSC transplantation exhibits promising therapeutic potential in DFU treatment, additional studies should be performed to confirm their efficacy and long-term safety in DFU patients.

A bispecific immunotoxin (IHPP) with a long half-life targeting HER2 and PDGFRß exhibited improved efficacy against HER2-positive tumors in a mouse xenograft model.

Multiple signaling pathways are usually involved in the development of tumors. Compared with monospecific antibodies, bispecific antibodies can recognize two different antigens at the same time, so they are more suitable for treating tumor diseases with complex etiology. Immunotoxins have good antitumor activity, however, single targeting limits their effectiveness. Herein, we designed a Pseudomonas exotoxin A (PE)-based bispecific immunotoxin IgBD-HER2-PDGFRß-PE38 which could distinguish HER2 and PDGFRß target in tumor. Meanwhile, IgG-affinity could extend the serum retention of immunotoxins after in vivo injection. In this work, we first detected the selective binding of the immunotoxins and antitumor effect in vitro. Compared with control group, IgBD-HER2-PDGFRß-PE38 exhibited improved efficacy against HER2-positive tumors in an NCI-N87 subcutaneous xenograft model. Then, transcriptome sequencing was performed on tumor tissue originating from different treatment groups of mice bearing NCI-N87 tumors. Seven significantly differentially expressed genes were screened based on human genes, and the differential mouse genes were enriched based on the Reactome Pathway Database. At last, the RNA sequencing results were verified by real-time PCR and ELISA. Therefore, the new construct bispecific immunotoxin represents a potentially attractive therapeutic modality, and the proposed strategy make them promising for use in the development of anti-HER2 cancer therapeutics.

Novel Regulators of Sugar-Mediated Lateral Root Development in Arabidopsis thaliana.

Lateral root development is a complex process regulated by numerous factors. An important role for sugar in lateral root development has been known for a while, but the underlying molecular basis still remains unclear. In this study, we first showed that WOX7, a sugar-inducible negative regulator of lateral root development, acts downstream of the glucose sensor HXK1. Using a transgenic line homozygous for a transgene expressing GFP under the control of the WOX7 promoter, we next performed a genetic screen to identify additional genes in this development pathway. A number of mutants with altered level of WOX7 expression were recovered, and two with increased WOX7 expression, named ewe-1 and ewe-2 (for Enhanced WOX7 Expression), were further characterized. Both mutants manifest delayed lateral root development, and genetic analysis indicates that single recessive mutations are responsible for the observed phenotypes. The mutations were then located to similar regions on chromosome 2 by marker-assisted analyses, and candidate genes were identified through whole genome sequencing. The significance and limitations of this work are discussed.

Stem cell therapy: a potential approach for treatment of influenza virus and coronavirus-induced acute lung injury.

Acute lung injury (ALI), an increasingly devastating human disorder, is characterized by a multitude of lung changes arising from a wide variety of lung injuries. Viral infection is the main cause of morbidity and mortality in ALI and acute respiratory distress syndrome (ARDS) patients. In particular, influenza virus, coronavirus, and other respiratory viruses circulate in nature in various animal species and can cause severe and rapidly spread human infections. Although scientific advancements have allowed for rapid progress to be made to understand the pathogenesis and develop therapeutics after each viral pandemic, few effective methods to treat virus-induced ALI have been described. Recently, stem cell therapy has been widely used in the treatment of various diseases, including ALI. In this review, we detail the present stem cell-based therapeutics for lung injury caused by influenza virus and the outlook for the future state of stem cell therapy to deal with emerging influenza and coronaviruses.

Selaginellin B induces apoptosis and autophagy in pancreatic cancer cells via the JAK2/STAT3 signaling pathway.

Selaginella tamariscina (ST), a well-known traditional medicinal plant, has been used to treat various cancers, including pancreatic cancer. However, the underlying mechanism by which Selaginellin B, a natural pigment isolated and purified from ST, protects against pancreatic cells has yet to be fully elucidated. In the present study, the biological functions of Selaginellin B were investigated using apoptosis, migration and colony formation assays in ASPC-1 and PANC-1 cells. In addition, apoptosis-associated proteins were detected by Western blotting. Our results demonstrated that Selaginellin B induced apoptosis, as evidenced by the increased cleaved caspase-3 level and Bax/Bcl-2 ratio. Moreover, Selaginellin B led to a marked up-regulation of the ratio of LC3-II/LC3-I in ASPC-1 and PANC-1 cells, respectively. Furthermore, reverse pharmacophore screening, molecular docking and molecular dynamics simulation studies revealed that Janus kinase 2 (JAK2) may be a potential target for Selaginellin B. In summary, the results of the present research have demonstrated that Selaginellin B is an effective anticancer agent against PANC-1 and ASPC-1 cells, and the compound holds great promise for the treatment of pancreatic cancer.

Correction to: AFF1 and AFF4 differentially regulate the osteogenic differentiation of human MSCs.

[This corrects the article DOI: 10.1038/boneres.2017.44.].