Membrane-Bound CD40L Promotes Senescence and Initiates Senescence-Associated Secretory Phenotype via NF-κB Activation in Lung Adenocarcinoma.

BACKGROUND/AIMS: Cellular senescence acts as a barrier against tumorigenesis. The CD40L transgene, expressed in some tumor cells, not only becomes visible to antigen-presenting cells but also actively catalyzes its own termination. Here, we evaluated the effect of a membrane-bound mutant form of human CD40L (CD40L-M) on senescence and the senescence-associated secretory phenotype (SASP) in non-small cell lung cancer (NSCLC). METHODS: CD40 expression levels in the NSCLC cell lines A549/TR, A549/DDP and H460 were examined by flow cytometry. Senescent cells and tissues were identified via SA-ß-gal activity. Cell proliferation was visualized by EdU labeling. qRT-PCR, Western blotting, and immunofluorescence staining were conducted to assess mRNA and protein expression levels of CD40L, γ-H2A.X, p65, p-p65, IκBα, p53, p21 and p16. Cytokines secreted from transfected cells were tested by ELISA and cell migration assay. Capsid tyrosine-modified rAAV5-CD40L-M was packaged and carried out in vivo. RESULTS: Overexpression of CD40L-M promoted senescence, inhibited proliferation, increased DNA damage-associated γ-H2A.X, and initiated the SASP in CD40-positive NSCLC cells. NF-κB signaling was activated by CD40L-M overexpression in these cells. Knockdown of NF-κB partially overcame senescence and failed to induce SASP. Furthermore, increased p53 and p21 protein levels induced by CD40L-M were also reduced following NF-κB suppression. CONCLUSIONS: These data showed that the membrane-bound CD40L mutant may promote cellular senescence and initiate the SASP of NSCLC cells in an NF-κB-dependent manner. Therefore, CD40L-M-induced senescence may be a potential approach to protect against lung adenocarcinoma.

Efficacy of shoulder arthroscopic surgery for the treatment of rotator cuff injury: A protocol of systematic review and meta-analysis.

BACKGROUND: This study will investigate the efficacy and safety of shoulder arthroscopic surgery (SAS) for patients with rotator cuff injury (RCI). METHODS: We will systematically search for randomized controlled trials in the electronic databases of PUBMED, EMBASE, Cochrane Library, CINAHL, PsycINFO, Web of Science, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure. All above databases will be searched from their beginning to March 1, 2020 without language restrictions. Two reviewers will independently scan retrieved records, evaluate study quality and extract data. If possible, we will synthesize the data and conduct a meta-analysis by RevMan 5.3 software. RESULTS: This systematic review will summarize the most recent evidence to explore the efficacy and safety of SAS for patients with RCI. CONCLUSION: The findings of this study will help to provide a genuine understanding of perspective from a scientific basis on the efficacy and safety of SAS for patients with RCI. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42020170009.

Ventilator for the management of patients with severe pneumonia: A protocol of systematic review.

BACKGROUND: This study will assess the efficacy and safety of ventilator for the management of severe pneumonia (SP). METHODS: This study will search the following electronic databases in MEDLINE, EMBASE, Web of Science, PsycINFO, Cochrane Library, CNKI, and Scopus from the beginning to present without language restrictions. Two authors will screen all records according to the eligibility criteria; assess study quality; and extract all essential data from eligible studies. If sufficient studies are included, we will pool the extracted data and carry out meta-analysis. RESULTS: This study will summarize published studies to assess the efficacy and safety of ventilator for patients with SP. CONCLUSION: The results of this study may supply a genuine understanding of perspective from a scientific basis on ventilator for the management of patients with SP.

Tumor M2-pyruvate kinase in stool as a biomarker for diagnosis of colorectal cancer: A meta-analysis.

OBJECTIVE: The aim of this meta-analysis was to evaluate the diagnosis value of tumor M2-pyruvate kinase (M2-PK) in stool as a biomarker for diagnosis of colorectal cancer. MATERIALS AND METHODS: By searching the databases of Cochrane Library, PubMed, China national knowledge Information and Wanfang, the diagnosis study related to tumor M2-PK in stool as a biomarker for diagnosis of colorectal cancer were screened and included in this study. The pooled sensitivity, specificity, positive likelihood ratio (+LR), negative likelihood ratio (-LR) and the receiver operating characteristic curve (ROC) were calculated by stata 11.0 software. RESULTS: According to the including criteria, 14 trials including 1990 subjects were finally included in this meta-analysis. The pooled diagnosis sensitivity, specificity, +LR, -LR and area under curve were 0.78 (95% confidence interval [CI]: 0.74-0.81), 0.77 (95% CI: 0.76-0.79), 4.38 (95% CI: 3.27-5.88), 0.28 (95% CI: 0.23-0.34) and 0.86 (95% CI: 0.834-0.89). No statistical publication bias was found in this study. CONCLUSION: Tumor M2-PK in stool can be a useful biomarker in the diagnosis of colorectal cancer with relative high sensitivity and specificity.

shRNA targeting Bmi1 impedes the self-renewal of cisplatin-enriched stem-like cells in human A549 cells.

It has been hypothesized that cancer stem-like cells are responsible for tumor recurrence following chemotherapy. Evidence on the mechanisms through which drug-resistant stem-like cells recapitulate the tumor mass has not been definitively reported. Based on this information, we investigated the enrichment ability of a population of stem-like cells following treatment with cisplatin in human A549 cells and focused on the molecular mechanisms regulating the self-renewal of stem-like cells. A population of stem-like cells was enriched following cisplatin treatment and was defined phenotypically and functionally based on the expression of certain stem cell markers, sphere-forming ability, multipotent differentiation and induction of xenograft tumors in vivo. For various types of differentiated cells, Bmi1 has been reported to be important for cell proliferation and for the self-renewal of stem cells. The high expression of Bmi1 in cisplatin-enriched stem-like cells was shown using Q-PCR and western blotting; therefore, the role of Bmi1 was investigated in cisplatin-enriched stem-like cells by infecting cisplatin-enriched stem-like cells with Bmi1-targeted RNAi lentiviruses. Cell proliferation, tumor sphere formation and xenograft formation was reduced following knockdown of Bmi1. Based on our results, we propose that, after cisplatin treatment, Bmi1 is required for the self-renewal of stem-like cells that are important for the expansion of the stem-like cell pool in human A549 cells and that targeting Bmi1 slows down the formation of tumors in vivo.

Determination and pharmacokinetics of DT-13 in rat plasma by LC-MS.

A sensitive and specific LC-MS assay for DT-13 in rat plasma was developed. DT-13 is an active steroidal saponin present in Liriopes Radix and is developed as an anti-tumor drug candidate. The samples were extracted by acetonitrile-mediated plasma protein precipitation. The chromatographic separation was carried out using a Ultimate C(18) column (250 mm × 4.6 mm, i.d., 5 µm) with a mobile phase composed of acetonitrile: 5 mmol/L aqueous ammonium acetate (60:40, v:v). The method was validated and the specificity, linearity (r(2)=0.9980 within 10-1000 ng/mL), lower limit of quantitation (LLOQ, 10 ng/mL), precision (intra- and inter-day <12.3%), accuracy (93.4-106.3%), recovery (91.0 ± 4.7%) and stability were determined. The method was applied to the pharmacokinetic study of DT-13 in rat plasma after intravenous and intragastric administration. The results showed DT-13 underwent a prolonged absorption and slow elimination with a low oral bioavailability (5.51%) in rats.

Heparin changes the conformation of high-mobility group protein 1 and decreases its affinity toward receptor for advanced glycation endproducts in vitro.

High-mobility group protein 1 (HMGB1) has been identified as a late-acting mediator of inflammation. The receptor for advanced glycation end products (RAGE) is the main receptor and mediates the cytokine activity of HMGB1. Since HMGB1 also exhibits heparin-binding activity, we investigated whether heparin interferes with HMGB1/RAGE interaction and prevents the cytokine activity. We used fluorescence spectrometry, circular dichroism spectrometry and SPR biosensor technique to evaluate the effect. After treatment of HMGB1 with different concentrations of heparin (0, 50, 100 and 1000 U/L), the fluorescence peak values of HMGB1 increased and the emission wavelength showed red shifts; further, the secondary structure of HMGB1 showed a marked change in that the content of ß-pleated sheet reduced while that of α-helix increased. The equilibrium dissociation constants (K(D)) were determined by SPR technique; K(D)=4.5 × 10(-9)mol/L for heparin and HMGB1 and K(D)=9.77 × 10(-8)mol/L for HMGB1 and RAGE, respectively. Heparin and RAGE had no interaction. The amount of HMGB1 and RAGE bound forms reduced after treatment with heparin. ELISA revealed that addition of heparin inhibited the TNF-α and IL-6 released by macrophages RAW264.7 and HUVEC; 10 U/L and 50 U/L of heparin showed the most marked inhibitory effect in RAW264.7 cells and in HUVEC, respectively. In conclusion, heparin can combine with HMGB1 and affect the affinity of HMGB1/RAGE by changing the conformation of HMGB1. And this effect was independent of heparin concentration, so that a low dose of heparin was sufficient to achieve the best anti-inflammatory effect in our test.