243 research outputs found

    Tumor cell-derived PDGF-B potentiates mouse mesenchymal stem cells-pericytes transition and recruitment through an interaction with NRP-1

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    <p>Abstract</p> <p>Background</p> <p>New blood vessel formation, or angiogenic switch, is an essential event in the development of solid tumors and their metastatic growth. Tumor blood vessel formation and remodeling is a complex and multi-step processes. The differentiation and recruitment of mural cells including vascular smooth muscle cells and pericytes are essential steps in tumor angiogenesis. However, the role of tumor cells in differentiation and recruitment of mural cells has not yet been fully elucidated. This study focuses on the role of human tumor cells in governing the differentiation of mouse mesenchymal stem cells (MSCs) to pericytes and their recruitment in the tumor angiogenesis process.</p> <p>Results</p> <p>We show that C3H/10T1/2 mouse embryonic mesenchymal stem cells, under the influence of different tumor cell-derived conditioned media, differentiate into mature pericytes. These differentiated pericytes, in turn, are recruited to bind with capillary-like networks formed by endothelial cells on the matrigel under <it>in vitro </it>conditions and recruited to bind with blood vessels on gel-foam under <it>in vivo </it>conditions. The degree of recruitment of pericytes into <it>in vitro </it>neo-angiogenesis is tumor cell phenotype specific. Interestingly, invasive cells recruit less pericytes as compared to non-invasive cells. We identified tumor cell-secreted platelet-derived growth factor-B (PDGF-B) as a crucial factor controlling the differentiation and recruitment processes through an interaction with neuropilin-1 (NRP-1) in mesenchymal stem cells.</p> <p>Conclusion</p> <p>These new insights into the roles of tumor cell-secreted PDGF-B-NRP-1 signaling in MSCs-fate determination may help to develop new antiangiogenic strategies to prevent the tumor growth and metastasis and result in more effective cancer therapies.</p

    Cyr61/CCN1 signaling is critical for epithelial-mesenchymal transition and stemness and promotes pancreatic carcinogenesis

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    <p>Abstract</p> <p>Background</p> <p>Despite recent advances in outlining the mechanisms involved in pancreatic carcinogenesis, precise molecular pathways and cellular lineage specification remains incompletely understood.</p> <p>Results</p> <p>We show here that Cyr61/CCN1 play a critical role in pancreatic carcinogenesis through the induction of EMT and stemness. Cyr61 mRNA and protein were detected in the early precursor lesions and their expression intensified with disease progression. Cyr61/CCN1 expression was also detected in different pancreatic cancer cell lines. The aggressive cell lines, in which the expressions of mesenchymal/stem cell molecular markers are predominant; exhibit more Cyr61/CCN1 expression. Cyr61 expression is exorbitantly higher in cancer stem/tumor initiating Panc-1-side-population (SP) cells. Upon Cyr61/CCN1 silencing, the aggressive behaviors are reduced by obliterating interlinking pathobiological events such as reversing the EMT, blocking the expression of stem-cell-like traits and inhibiting migration. In contrast, addition of Cyr61 protein in culture medium augments EMT and stemness features in relatively less aggressive BxPC3 pancreatic cancer cells. Using a xenograft model we demonstrated that cyr61/CCN1 silencing in Panc-1-SP cells reverses the stemness features and tumor initiating potency of these cells. Moreover, our results imply a miRNA-based mechanism for the regulation of aggressive behaviors of pancreatic cancer cells by Cyr61/CCN1.</p> <p>Conclusions</p> <p>In conclusion, the discovery of the involvement of Cyr61/CCN1 in pancreatic carcinogenesis may represent an important marker for PDAC and suggests Cyr61/CCN1 can be a potential cancer therapeutic target.</p

    A Second Generation 2-Methoxyestradiol Prodrug Is Effective Against Barrett's Adenocarcinoma in a Mouse Xenograft Model

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    This is the author's accepted manuscript. The original is available at http://mct.aacrjournals.org/content/12/3/2552-Methoxyestradiol (2-ME2) is an endogenous metabolite of estradiol. In preclinical models, 2-ME2 is effective against different types of tumors. Unfortunately, only low systemic concentrations of 2-ME2 can be achieved following oral administration, even after very high doses are administered to patients. In an effort to solve this problem we have now synthesized and tested a new prodrug of 2-ME2 that is water soluble due to a bio-reversible hydrophilic group added at the 3-position and more effectively resists metabolic inactivation due to an ester moiety added to mask the 17-position alcohol. We are reporting here for the first time that this double prodrug of 2-ME2 is effective as an antiproliferative and anti-cancer agent for both in vitro and in vivo studies against Barrett's esophageal adenocarcinoma (BEAC), and provided greater potency than 2-ME2 in inhibiting the growth of BEAC xenografts. Finally, studies indicate that, like 2-ME2, the 2-ME2-PD1 exhibits anticancer effect through possible disruption of microtubule-network

    Woman-centered research on access to safe abortion services and implications for behavioral change communication interventions: a cross-sectional study of women in Bihar and Jharkhand, India

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    <p>Abstract</p> <p>Background</p> <p>Unsafe abortion in India leads to significant morbidity and mortality. Abortion has been legal in India since 1971, and the availability of safe abortion services has increased. However, service availability has not led to a significant reduction in unsafe abortion. This study aimed to understand the gap between safe abortion availability and use of services in Bihar and Jharkhand, India by examining accessibility from the perspective of rural, Indian women.</p> <p>Methods</p> <p>Two-stage stratified random sampling was used to identify and enroll 1411 married women of reproductive age in four rural districts in Bihar and Jharkhand, India. Data were collected on women's socio-demographic characteristics; exposure to mass media and other information sources; and abortion-related knowledge, perceptions and practices. Multiple linear regression models were used to explore the association between knowledge and perceptions about abortion.</p> <p>Results</p> <p>Most women were poor, had never attended school, and had limited exposure to mass media. Instead, they relied on community health workers, family and friends for health information. Women who had knowledge about abortion, such as knowing an abortion method, were more likely to perceive that services are available (Ī² = 0.079; p < 0.05) and have positive attitudes toward abortion (Ī² = 0.070; p < 0.05). In addition, women who reported exposure to abortion messages were more likely to have favorable attitudes toward abortion (Ī² = 0.182; p < 0.05).</p> <p>Conclusions</p> <p>Behavior change communication (BCC) interventions, which address negative perceptions by improving community knowledge about abortion and support local availability of safe abortion services, are needed to increase enabling resources for women and improve potential access to services. Implementing BCC interventions is challenging in settings such as Bihar and Jharkhand where women may be difficult to reach directly, but interventions can target individuals in the community to transfer information to the women who need this information most. Interpersonal approaches that engage community leaders and influencers may also counteract negative social norms regarding abortion and associated stigma. Collaborative actions of government, NGOs and private partners should capitalize on this potential power of communities to reduce the impact of unsafe abortion on rural women.</p

    Dynamics of Hot QCD Matter -- Current Status and Developments

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    The discovery and characterization of hot and dense QCD matter, known as Quark Gluon Plasma (QGP), remains the most international collaborative effort and synergy between theorists and experimentalists in modern nuclear physics to date. The experimentalists around the world not only collect an unprecedented amount of data in heavy-ion collisions, at Relativistic Heavy Ion Collider (RHIC), at Brookhaven National Laboratory (BNL) in New York, USA, and the Large Hadron Collider (LHC), at CERN in Geneva, Switzerland but also analyze these data to unravel the mystery of this new phase of matter that filled a few microseconds old universe, just after the Big Bang. In the meantime, advancements in theoretical works and computing capability extend our wisdom about the hot-dense QCD matter and its dynamics through mathematical equations. The exchange of ideas between experimentalists and theoreticians is crucial for the progress of our knowledge. The motivation of this first conference named "HOT QCD Matter 2022" is to bring the community together to have a discourse on this topic. In this article, there are 36 sections discussing various topics in the field of relativistic heavy-ion collisions and related phenomena that cover a snapshot of the current experimental observations and theoretical progress. This article begins with the theoretical overview of relativistic spin-hydrodynamics in the presence of the external magnetic field, followed by the Lattice QCD results on heavy quarks in QGP, and finally, it ends with an overview of experiment results.Comment: Compilation of the contributions (148 pages) as presented in the `Hot QCD Matter 2022 conference', held from May 12 to 14, 2022, jointly organized by IIT Goa & Goa University, Goa, Indi

    2-Methoxyestradiol Exhibits a Biphasic Effect on VEGF-A in Tumor Cells and Upregulation Is Mediated Through ER-Ī±: A Possible Signaling Pathway Associated with the Impact of 2-ME(2) on Proliferative Cells

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    2-Methoxyestradiol (2-ME(2)) was reported to elicit both stimulation and inhibition of tumor angiogenesis and growth depending on the dosage used. However, the mechanism(s) of the biphasic action of 2-ME(2) has been elusive. Here we describe a regulatory role of vascular endothelial growth factor-A (VEGF-A) in the biphasic effects on estrogen receptor (ER)(+) GH3 rat pituitary tumor cells and MCF-7 human breast tumor cells depending on the dosage of 2-ME(2) used. We observed that acute exposure to 2-ME(2), irrespective of dosage, did not alter cellular proliferation, but enhanced the VEGF-A mRNA level. As the treatment duration increased, biphasic effect was elicited. A concentration of 1 ĀµM 2-ME(2) increased both cell proliferation and VEGF-A levels in these cells, whereas higher doses exhibited reversed impact. A low dose of 2-ME(2) also increased the VEGF-A mRNA expression in ER-Ī±-transfected human mammary epithelial cells (HMECs). The effect was reversed in ER(-) cells. The enhanced expression of VEGF-A mRNA could be blocked by the pure estrogen antagonist, ICI 182,780, and reveal that the upregulation of VEGF-A expression by 2-ME(2) is mediated through ER-Ī±. Furthermore, the biphasic effect of 2-ME(2) on cell proliferation can be modulated by administrating VEGF-A antibodies or VEGF-A proteins. Studies also demonstrate that the VEGF-A protein, induced by 2-ME(2), is functionally active and upregulates the proliferation of adjacent endothelial cells

    Glucose induced fractal colony pattern of Bacillus thuringiensis

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    Growing colonies of bacteria on the surface of thin agar plates exhibit fractal patterns as a result of nonlinear response to environmental conditions, such as nutrients, solidity of the agar medium and temperature. Here, we examine the effect of glucose on pattern formation by growing colonies of Bacillus thuringiensis isolate KPWP1. We also present the theoretical modeling of the colony growth of KPWP1 and the associated spatio-temporal patterns. Our experimental results are in excellent agreement with simulations based on a reaction-diffusion model that describes diffusion-limited aggregation and branching, in which individual cells move actively in the periphery, but become immotile in the inner regions of the growing colony. We obtain the Hausdorff fractal dimension of the colony patterns: DH.Expt=1.1969 and DH, R.D.=1.1965, for experiment and reaction-diffusion model, respectively. Results of our experiments and modeling clearly show how glucose at higher concentration can prove to be inhibitory for motility of growing colonies of B. thuringiensis cells on semisolid support and be responsible for changes in the growth pattern
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