Differential Effects of Bartonella henselae on Human and Feline Macro- and Micro-Vascular Endothelial Cells

Bartonella henselae, a zoonotic agent, induces tumors of endothelial cells (ECs), namely bacillary angiomatosis and peliosis in immunosuppressed humans but not in cats. In vitro studies on ECs represent to date the only way to explore the interactions between Bartonella henselae and vascular endothelium. However, no comparative study of the interactions between Bartonella henselae and human (incidental host) ECs vs feline (reservoir host) ECs has been carried out because of the absence of any available feline endothelial cell lines

The advantages of hypnosis intervention on breast cancer surgery and adjuvant therapy

BACKGROUND: In oncology, hypnosis has been used for pain relief in metastatic patients but rarely for induction of anesthesia. MATERIAL AND METHOD: Between January 2010 and October 2015, 300 patients from our Breast Clinic (Cliniques universitaires Saint-Luc, Université catholique de Louvain) were included in an observational, non-randomized study approved by our local ethics committee (ClinicalTrials.gov - NCT03003611). The hypothesis of our study was that hypnosis intervention could decrease side effects of breast surgery. 150 consecutive patients underwent breast surgery while on general anesthesia (group I), and 150 consecutive patients underwent the same surgical procedures while on hypnosis sedation (group II). After surgery, in each group, 32 patients received chemotherapy, radiotherapy was administered to 123 patients, and 115 patients received endocrine therapy. RESULTS: Duration of hospitalization was statistically significantly reduced in group II versus group I: 3 versus 4.1 days (p = 0.0000057) for all surgical procedures. The number of post-mastectomy lymph punctures was reduced in group II (1-3, median value n = 1.5) versus group I (2-5, median value n = 3.1) (p = 0.01), as was the quantity of lymph removed (103 ml versus 462.7 ml) (p = 0.0297) in the group of mastectomies. Anxiety scale was also statistically reduced in the postoperative period among the group of patients undergoing surgery while on hypnosis sedation (p = 0.0000000000000002). The incidence of asthenia during chemotherapy was statistically decreased (p = 0.01) in group II. In this group, there was a statistically non-significant trend towards a decrease in the incidence of nausea/vomiting (p = 0.1), and the frequency of radiodermitis (p = 0.002) and post-radiotherapy asthenia (p = 0.000000881) was also reduced. Finally, the incidence of hot flashes (p = 0.0000000000021), joint and muscle pain (p = 0.0000000000021) and asthenia while on endocrine therapy (p = 0.000000022) were statistically significantly decreased in group II. DISCUSSION: Hypnosis sedation exerts beneficial effects on nearly all modalities of breast cancer treatment. CONCLUSION: Benefits of hypnosis sedation on breast cancer treatment are very encouraging and further promote the concept of integrative oncology

Myeloid cells are tunable by a polyanionic polysaccharide derivative and co-determine host rescue from lethal virus infection

Insight into molecular and cellular mechanisms of innate immunity is critical to understand viral pathogenesis and immunopathology and might be exploited for therapy. Whereas the molecular mechanisms of the IFN defense are well established, cellular mechanisms of antiviral immunity are only emerging, and their pharmacological triggering remains unknown. COAM is a polysaccharide derivative with antiviral activity but without comprehension about its mechanism of action. The COAM mixture was fractionated, and prophylactic treatment of mice with COAM polymers of high MW resulted in a conversion from 100% lethal mengovirus infection to an overall survival rate of 93% without obvious clinical sequelae. Differential and quantitative analysis of peritoneal leukocytes demonstrated that COAM induced a profound influx of neutrophils. Selective cell depletion experiments pointed toward neutrophils and macrophages as key effector cells in the rescue of mice from lethal mengovirus. COAM was able to induce mRNA and protein expression of the mouse neutrophil chemokine GCP-2. Binding of GCP-2 to COAM was demonstrated in solution and confirmed by SPR technology. Although COAM was not chemotactic for neutrophils, COAM-anchored muGCP-2 retained chemotactic activity for human and mouse neutrophils. In conclusion, this study established that COAM rescued mice from acute and lethal mengovirus infection by recruiting antiviral leukocytes to the site of infection, as proposed through the induction, binding, and concentration of endogenous chemokines. These findings reinforce the role of neutrophils and macrophages as critical cells that can be manipulated toward antiviral defense. J. Leukoc. Biol. 88: 1017-1029; 2010.Stemcel biology/Regenerative medicine (incl. bloodtransfusion

Alteration of cathepsin D trafficking induced by hypoxia and extracellular acidification in MCF-7 breast cancer cells

International audienceThe microenvironment that surrounds tumor cells is characterized by hypoxic conditions and extracellular acidity. These hostile conditions induce crucial changes in cell behavior and can promote the secretion of many soluble factors such as growth factors, cytokines and enzymes. The lysosomal aspartyl-endopeptidase cathepsin D (CD) is a marker of poor prognosis in breast cancer and is associated with a metastatic risk. In this study, the transport of CD was investigated in a model of breast cancer cells line (MCF-7) cultivated under hypoxia and acidification of media. CD secretion was assessed using Western blot analysis and protease activity was measured in conditioned culture media. We demonstrate that cultured MCF-7 cells secrete an active 52 kDa pCD precursor and report that under hypoxia there was an increased amount of pCD secreted. More surprisingly, extracellular acidification (pH 6 and 5.6) induced the secretion of the fully-mature and active (34 kDa + 14 kDa) double chain CD. Our findings reflect the fact that chemical anomalies influence the secretion path of CD in a breast cancer cell model, resulting in altered trafficking of the mature form. This important result may provide new arguments in favor of the role of extracellular CD in the degradation of the matrix proteins that constitute the breast tumor microenvironment

Hypoxia-Regulated Overexpression of Soluble VEGFR2 Controls Angiogenesis and Inhibits Tumor Growth

International audienceVEGFs are found at high levels in hypoxic tumors. As major components directing pathologic neovascularization, they regulate stromal reactions. Consequently, novel strategies targeting and inhibiting VEGF overproduction upon hypoxia offer considerable potential for modern anticancer therapies controlling rather than destroying tumor angiogenesis. Here, we report the design of a vector expressing the soluble form of VEGF receptor-2 (sVEGFR2) driven by a hypoxia-responsive element (HRE)-regulated promoter. To enable in vivo imaging by infrared visualization, mCherry and IFP1.4 coding sequences were built into the vector. Plasmid construction was validated through transfection into embryonic human kidney HEK293 and murine B16F10 melanoma cells. sVEGFR2 was expressed in hypoxic conditions only, confirming that the gene was regulated by the HRE promoter. sVEGFR2 was found to bind efficiently and specifically to murine and human VEGF-A, reducing the growth of tumor and endothelial cells as well as impacting angiogenesis in vitro. The hypoxia-conditioned sVEGFR2 expression was shown to be functional in vivo: Tumor angiogenesis was inhibited and, on stable transfection of B16F10 melanoma cells, tumor growth was reduced. Enhanced expression of sVEGFR2 was accompanied by a modulation in levels of VEGF-A. The resulting balance reflected the effect on tumor growth and on control of angiogenesis. A concomitant increase of intratumor oxygen tension also suggested an influence on vessel normalization. The possibility to express an angiogenesis regulator as sVEGFR2, in a hypoxia-conditioned manner, significantly opens new strategies for tumor vessel–controlled normalization and the design of adjuvants for combined cancer therapies

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