Podcasts about hmec

A new research paper was published in Oncotarget's Volume 14 on February 2, 2023, entitled, “Everolimus downregulates STAT3/HIF-1α/VEGF pathway to inhibit angiogenesis and lymphangiogenesis in TP53 mutant head and neck squamous cell carcinoma (HNSCC).” TP53 mutant head and neck squamous cell carcinoma (HNSCC) patients exhibit poor clinical outcomes with 50–60% recurrence rates in advanced stage patients. In a recent phase II clinical trial, adjuvant therapy with everolimus (mTOR inhibitor) significantly increased 2-year progression-free survival in p53 mutated patients. TP53-driven mTOR activation in solid malignancies causes upregulation of HIF-1α and its target, downstream effector VEGF, by activating STAT3 cell signaling pathway. In this recent study, researchers Md Maksudul Alam, Janmaris Marin Fermin, Mark Knackstedt, Mackenzie J. Noonan, Taylor Powell, Landon Goodreau, Emily K. Daniel, Xiaohua Rong, Tara Moore-Medlin, Alok R. Khandelwal, and Cherie-Ann O. Nathan from LSU-Health Sciences Center investigated the effects of everolimus on the STAT3/HIF-1α/VEGF pathway in TP53 mutant cell lines and xenograft models. “The role of mTOR inhibitors (mTORi) as potent growth inhibitory and antiangiogenic/anti-lymphangiogenic agents in HNSCC is well established [18]. Moreover, mTORi significantly suppressed baseline invasiveness of endothelial and HNSCC tumor cells [19]. However, the underlying molecular mechanisms for mutant p53 protein-mediated activation of the mTOR pathway which drive the oncologic processes in HNSCC are yet to be elucidated.” Treatment with everolimus significantly inhibited cell growth in vitro and effectively reduced the growth of TP53 mutant xenografts in a minimal residual disease (MRD) model in nude mice. Everolimus treatment was associated with significant downregulation of STAT3/HIF-1α/VEGF pathway in both models. Further, treatment with everolimus was associated with attenuation in tumor angiogenesis and lymphangiogenesis as indicated by decreased microvessel density of vascular and lymphatic vessels in HN31 and FaDu xenografts. Everolimus downregulated the STAT3/HIF-1α/VEGF pathway to inhibit growth and in vitro tube formation of HMEC-1 (endothelial) and HMEC-1A (lymphatic endothelial) cell lines. “Our studies demonstrated that everolimus inhibits the growth of TP53 mutant tumors by inhibiting angiogenesis and lymphangiogenesis through the downregulation of STAT3/HIF-1α/VEGF signaling.” DOI: https://doi.org/10.18632/oncotarget.28355 Correspondence to: Cherie-Ann O. Nathan - cherieann.nathan@lsuhs.edu Keywords: TP53 mutant, HNSCC, angiogenesis, everolimus, mTOR About Oncotarget Oncotarget is a primarily oncology-focused, peer-reviewed, open access journal. Papers are published continuously within yearly volumes in their final and complete form, and then quickly released to Pubmed. On September 15, 2022, Oncotarget was accepted again for indexing by MEDLINE. Oncotarget is now indexed by Medline/PubMed and PMC/PubMed. To learn more about Oncotarget, please visit https://www.oncotarget.com and connect with us: SoundCloud - https://soundcloud.com/oncotarget Facebook - https://www.facebook.com/Oncotarget/ Twitter - https://twitter.com/oncotarget Instagram - https://www.instagram.com/oncotargetjrnl/ YouTube - https://www.youtube.com/OncotargetYouTube LinkedIn - https://www.linkedin.com/company/oncotarget Pinterest - https://www.pinterest.com/oncotarget/ Reddit - https://www.reddit.com/user/Oncotarget/ Media Contact MEDIA@IMPACTJOURNALS.COM 18009220957

Kampuni ya uhandisi kutoka Thailand, HMEC, inayofanya kazi kwa pamoja na ujumbe wa Umoja wa Mataifa wa kulinda amani Sudan Kusini, UNMISS imepatia wakazi wa eneo la Yei mjini Juba mafunzo ya kilimo cha mazao ya chakula sambamba na mapishi kama njia mojawapo ya kujitegemea katika chakula.  (Taarifa ya Grace Kaneiya)

Anaplasma phagocytophilum (Ap) is a gram-negative, obligate intracellular bacterium that is able to infect different animal species and humans worldwide. Based on DNA sequencing, Ap has newly been reallocated from the genus Ehrlichia to the genus Anaplasma in the family Anaplasmataceae (DUMLER et al. 2001). In humans and animals, the clinical signs of Ap infection vary from mild symptoms to severe clinical outcomes, including death. However, the disease generally presents as undifferentiated fever accompanied by leucopenia, thrombocytopenia and increased serum transaminase activities (DUMLER et al. 2005; DUMLER et al. 2007; RIKIHISA 2011). Hard-bodied ticks of the genus Ixodes (family Ixodidae) are the main vectors for Ap dissemination. Compared to other pathogens such as Neorickettsia and Wolbachia spp., which can be transmitted from adult ticks to their offspring, Anaplasma and Ehrlichia spp. are the only Rickettsiales that are not transmitted transovarially (RIKIHISA 2011). Thus, ticks need to acquire Ap through blood feeding from infected hosts to complete the life cycle of Ap. During attachment of the tick, the bacterium is released by salivary secretion and is transmitted to the host. It is known that Ap multiplies within membrane-bound vacuoles (or called ‘morulae’) in the cytoplasm of peripheral granulocytes. The binding and infection of bacteria depends on the tetrasaccharide sialyl Lewisx (sLex or CD15s) of P-selectin glycoprotein ligand 1 (PSGL-1) on the surface of host cells, a factor expressed on peripheral granulocytes and HL-60 cells (GOODMAN et al. 1999; HERRON et al. 2000; RENEER et al. 2006; RENEER et al. 2008). Only little information is known about the transmission pathway of Ap after tick bite in the very early stage of infection. It is described that Ap is able to evade and replicate within microvascular endothelial cells in vitro (MUNDERLOH et al. 2004), while endothelial cells lining the inner lumen of blood vessels allow them to easily interact with any circulating blood cells. Since granulocytes do not return back to the blood stream after extravasation, it is reasonable to postulate that Ap evades and replicates within microvascular endothelial cells in the initial transmission, and subsequently transmits into peripheral granulocytes for ongoing dissemination. Therefore, the objective of the study was to establish a flow culture model that mimics the physiological environment in the blood vessel to study the possible transmission pathway of Ap between endothelial cells and polymorphonuclear leukocytes (PMNs). For this purpose, a novel ex vivo flow culture system was established. For experimental setup, human microvascular endothelial cell line (HMEC-1) and primary human dermal microvascular endothelial cells (HDMEC) were used. Under static conditions, Ap evades endothelial cells within 24 h, supporting the hypotheses that endothelial cells might be the first infection site of the pathogen in the host. Thereby a high level of interleukin-8, a chemokine that is known to recruit PMNs, secreted by Ap-infected endothelial cells was detected. Using the investigated flow culture model, it was shown for the first time, that Ap is able to translocate from endothelial cells to PMNs under dynamic flow conditions. Furthermore, under defined shear stress, an increased binding of PMNs to Ap-infected endothelial cells monolayer was observed, resulting from the elevated expression of adhesion molecules associated with PMNs recruitment on endothelial cells. The flow culture model investigated in this study can be used to study the interaction between Ap-infected endothelial cells and PMNs under physiological flow conditions, and is therefore helpful to study the infection mechanism in the early stage of Ap dissemination in the host.

Increased levels of reactive oxygen species (ROS) contribute to vascular diseases like pulmonary hypertension and atherosclerosis. Although a NOX2-containing NADPH oxidase similar to the neutrophil one has been described to be active in endothelial cells, the contribution of newly discovered NOX homologues (NOX1-NOX5) was still unclear. Therefore, the overall aim of this study was to better characterize the expression, regulation and function of NOX homologues in different endothelial cell models. First, we could demonstrate the presence of NOX1, NOX2, NOX4, NOX5 including NOX5S as well as p22phox mRNA and protein levels in Ea.Hy926 or HMEC-1 cells. Furthermore, NOX5 protein was also present in endothelial and smooth muscle cells in the vascular wall of spleen and lung tissue. We found that NOX2, NOX4 and NOX5 were present in an intracellular perinuclear compartment, whereby NOX2 and NOX4 could be localized simultaneously in one cell. NOX2, NOX4, NOX5 were able to interact with p22phox and overexpression of NOX2, NOX4 and NOX5 increased ROS generation, although NOX5-dependent ROS generation did not require the presence of p22phox. NOX2, NOX4 and NOX5 also increased endothelial proliferation while depletion of NOX2, NOX4 and NOX5 decreased ROS generation, proliferation and tube forming ability indicating angiogenic activity under basal conditions. NOX2- and NOX4-induced proliferation was mediated by p38 MAP kinase. Although NOX1 expression as well as the expression of its regulatory subunits NOXO1 and NOXA1 was detectable in endothelial cells, depletion of NOX1 did not significantly affect basal ROS generation or proliferation of endothelial cells. Second, we could demonstrate the upregulation of NOX2, NOX5 and NOX5S after thrombin stimulation in endothelial cells and the modulation of p22phox expression in an ATF4- and XBP1-dependent manner under ER-stress conditions. Cellular stress either by thrombin or UPR also induced ROS generation of endothelial cells. In addition, thrombin induced proliferation and enhanced the tube forming ability of endothelial cells. Thrombin-induced ROS generation, proliferation and tube forming ability were diminished by silencing NOX2 or NOX5, whereas UPR induced ROS generation was inhibited by silencing p22phox as well as by silencing ATF4 or XBP1. In summary, this work provides evidence that in endothelial cells, NOX2, NOX4 and NOX5, but not NOX1, contribute to basal ROS generation, proliferation and angiogenesis and that the NOX proteins NOX2 and NOX5 as well as p22phox play an important role in the response to thrombin and ER-stress providing new insights in endothelial function and redox signaling.

In mammalian cell nuclei chromosome territories (CTs) occupy positions correlating with their gene-density and chromosome size. While this global radial order has been well documented, the question of whether a global neighborhood order is also maintained has remained a controversial matter. To answer this question I grew clones (of HeLa, HMEC and human diploid fibroblast cells) for up to 5 divisions (32 cells) and performed 3D FISH experiments to visualize the nuclear positions of 3 different CT pairs. Using different landmark-based registration approaches I assessed the similarity of CT arrangements in daughter cells and cousins. As expected from a symmetrical chromatid movement during mitotic anaphase and telophase, I was able to confirm previous findings of a pronounced similarity of CT arrangements between daughter cells. However, already after two cell cycles the neighborhood order in cousins was nearly completely lost. This loss indicates that a global neighborhood order is not maintained. Further, I could show in the present thesis that a gene density correlated distribution of CTs, which has already been shown in different cell types of various species appears to be independent of the cell cycle. Moreover I could provide evidence that the nuclear shape plays a major role in defining the extent of this gene-density correlated distribution, as nuclei of human, old world monkey and bovine fibroblasts showed an increased difference in the radial distribution of gene poor/dense CTs when their nuclei were artificially reshaped from a flat ellipsoid to a nearly spherical nucleus. The observation that a gene-density correlated distribution of CTs has been found in nuclei from birds to humans argues for a significant, yet undiscovered functional impact. So far CTs have been investigated mainly in cultured cells and to some extent in tissues, yet little is known about the origin and fate of CTs during early development. To gain insights into the very early organization of CTs in preimplantation embryos I have developed a fluorescence in situ hybridization (FISH) protocol, which enables the visualization of CTs in three dimensionally preserved embryos. Using this protocol I have investigated CTs of bovine chromosomes 19 and 20, representing the most gene-rich and gene-poor chromosomes, respectively. Equivalent to the distributions described in other species I could confirm a gene density related spatial CT arrangement in bovine fibroblasts and lymphocytes with CT 19 being localized more internally and CT 20 more peripherally. Importantly, I did not find a gene density related distribution of CTs 19 and 20 in early embryos up to the 8-cell stage. Only in embryos with more than 8 cells a significant difference in the distribution of both chromosomes became apparent that increased upon progression to the blastocyst stage. Since major genome activation in bovine embryos occurs during the 8- to 16-cell stage, my findings suggest an interrelation between higher order chromatin arrangements and transcriptional activation of the embryonic genome. Using another experimental set up I analyzed the topology of a developmentally regulated transgene utilizing bovine nuclear transfer (NT) embryos derived from fetal fibroblasts, which harbored a mouse Oct4/GFP reporter construct integrated at a single insertion site on bovine chromosome 13. I analyzed the intranuclear distribution of the transgene as well as its position in relation to its harboring chromosome in donor cell nuclei and day 2 NT embryos, where the transgene is still inactive as well as in day 4 NT embryos, where transgene expression starts, and day 7 NT embryos, where expression is highly increased. Compared to donor cell nuclei I found a more peripheral location of both BTA 13 CTs and the Oct4/GFP transgene in day 2, day 4 and day 7 NT embryos, although there was a trend of the transgene and both BTA 13 CTs to re-localize towards the nuclear interior from d2 to d7 embryos. Moreover, I found the transgene located at the surface of its harboring CT 13 in donor fibroblasts, whereas during preimplantation development of NT embryos it became increasingly internalized into the chromosome 13 territory, reaching a maximum in d7 NT embryos, i.e. at the developmental stage when its transcription levels are highest. These latter experiments show that the transfer of a somatic nucleus into a chromosome depleted oocyte triggers a large scale positional change of CTs 13 and of an Oct4/GFP transgene and indicate a redistribution of this developmentally regulated Oct4/GFP transgene during activation and upregulation in developing NT embryos.

Neben den klassischen kardiovaskulären Risikofaktoren wie arterielle Hypertonie oder Hypercholesterinämie kommen den psychosozialen Faktoren wie Stress oder Depression eine entscheidene Rolle als Risikofaktor für die Entwicklung der Atherosklerose zu. Obwohl das chronische Stresshormon Corticotropin-Releasing-Hormon im Rahmen der adaptiven Stressantwort als Hauptvertreter der Effektorhormone angesehen wird, sind die pathophysiologischen Mechanismen, die zu einer CRH/Stress-bedingten endothelialen Dysfunktion führen, weitgehend unbekannt. Diese Arbeit hatte zum Ziel, den Effekt von peripherem CRH auf die Monozyten/Endothel-Interaktion, beispielhaft die Adhäsion, herauszuarbeiten. Die Untersuchungen der Monozyten-Endothel-Adhäsion wurde in einem in-vitro-Modell unter Verwendung der Zelllinien HMEC-1 und THP-1 mit einer neuen, modifizierten fluorometrischen Methode untersucht, monozytäres MAC-1/CD11b, endotheliales ICAM-1/CD54 und VCAM-1/CD106 mit Hilfe der Durchflusszytometrie bestimmt. Der Nachweis der vermittelnden monozytären CRH-Rezeptoren R1/-R2 erfolgte mittels RT-PCR- und Immunfluoreszenztechnik. THP-1 konnte als Zielzelle für CRH mit Nachweis der CRH-Rezeptoren auf mRNA- und Proteinebene identifiziert werden. CRH induzierte eine signifikante zeit- und konzentrationsabhängige Adhäsionszunahme der THP-1 Zellen am HMEC-1 Monolayer. Der Effekt scheint Monozyten-vermittelt, da CRH, konzentrationsabhängig, zu einer monozytären MAC-1/CD11b-Freisetzung führte. Eine CRH-Stimulation nur von HMEC-1 führte hingegen zu keiner Adhäsionszunahme, erklärbar z. B. durch die hier dokumentierte fehlende Veränderung von endothelialem ICAM-1/CD54 und VCAM-1/CD106 unter Einfluß von CRH. Die Ergebnisse unterstreichen somit die Relevanz von peripherem CRH auf die Monozytenfunktion und Monozyten/Endothel-Interaktion. Sie können einen Beitrag zur Erklärung eines möglichen Zusammenhangs von chronischem Stress (mit konsekutiver Erhöhung des Stresshormons CRH) und der Initiation / Progression der endothelialen Dysfunktion leisten (Wilbert-Lampen, Straube et al., 2006).

Endothelial cell survival is indispensable to maintain endothelial integrity and initiate new vessel formation. We investigated the role of SHP-2 in proliferation, survival and sprouting of human microvascular- and umbilical vein endothelial cells (HMEC, HUVEC) using antisense oligonucleotides (AS-ODN) and a pharmacological SHP-2 inhibitor (PtpI IV). Knock-down of SHP-2 decreased bFGF and PDGF dependent endothelial cell proliferation (p