scholarly journals RENAL DEPOSITION OF SOLUBLE IMMUNE COMPLEXES IN MICE BEARING B-16 MELANOMA

1974 ◽  
Vol 140 (2) ◽  
pp. 410-425 ◽  
Author(s):  
Paula K. F. Poskitt ◽  
Thomas R. Poskitt ◽  
John H. Wallace

Histologic and immunofluorescence studies of the kidneys of mice bearing a progressive melanoma show a proliferative glomerulonephritis associated with immune complex deposition in the mesangium and along the glomerular basement membrane This immune complex disease is distinct from the age-associated disease of the C57BL/6J host strain and the complexes can be shown to consist of soluble tumor antigen and antitumor antibody. Furthermore, the intensity of IgG complex deposition correlates directly with tumor progress (size and metastases) and inversely with mononuclear leukocyte infiltration of the tumor. In vitro assays for lymphocyte cytotoxicity and humoral antibody were found to be less reliable indicators of tumor progress. The possible role of circulating soluble tumor antigen in modifying the immune response to tumors is discussed.

Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 3055
Author(s):  
Elisabetta Stanzani ◽  
Leire Pedrosa ◽  
Guillaume Bourmeau ◽  
Oceane Anezo ◽  
Aleix Noguera-Castells ◽  
...  

Therapeutic resistance after multimodal therapy is the most relevant cause of glioblastoma (GBM) recurrence. Extensive cellular heterogeneity, mainly driven by the presence of GBM stem-like cells (GSCs), strongly correlates with patients’ prognosis and limited response to therapies. Defining the mechanisms that drive stemness and control responsiveness to therapy in a GSC-specific manner is therefore essential. Here we investigated the role of integrin a6 (ITGA6) in controlling stemness and resistance to radiotherapy in proneural and mesenchymal GSCs subtypes. Using cell sorting, gene silencing, RNA-Seq, and in vitro assays, we verified that ITGA6 expression seems crucial for proliferation and stemness of proneural GSCs, while it appears not to be relevant in mesenchymal GSCs under basal conditions. However, when challenged with a fractionated protocol of radiation therapy, comparable to that used in the clinical setting, mesenchymal GSCs were dependent on integrin a6 for survival. Specifically, GSCs with reduced levels of ITGA6 displayed a clear reduction of DNA damage response and perturbation of cell cycle pathways. These data indicate that ITGA6 inhibition is able to overcome the radioresistance of mesenchymal GSCs, while it reduces proliferation and stemness in proneural GSCs. Therefore, integrin a6 controls crucial characteristics across GBM subtypes in GBM heterogeneous biology and thus may represent a promising target to improve patient outcomes.


2017 ◽  
Vol 32 (4) ◽  
pp. 403-408 ◽  
Author(s):  
Hongfen Liu ◽  
Qiang Zhen ◽  
Yakun Fan

Background Recent studies have shown that long noncoding RNA (IncRNA) gastric carcinoma highly expressed transcript 1 (GHET1) was involved in the progression of tumors. However, the role of GHET1 in esophageal squamous cell carcinoma (ESCC) remains unclear. Methods The expression of IncRNA GHET1 was examined in 55 paired ESCC tissues and adjacent nontumor tissues. Molecular and cellular techniques were used to explore the role of GHET1 on ESCC cells. Results Our data showed that GHET1 expression was significantly increased in ESCC tissues and cell lines. High GHET1 expression in ESCC tissues was significantly associated with poor differentiation, advanced tumor nodes metastasis stage, and lymph node metastasis. GHET1 showed high sensitivity and specificity for diagnosing ESCC. Our data from in vitro assays showed that GHET1 inhibition suppressed ESCC cells proliferation, migration, and invasion, and induced cells apoptosis. Furthermore, western blot showed that GHET1 inhibition significantly decreased the expression of vimentin and N-cadherin while it increased the expression of E-cadherin. Conclusions Our study indicates that GHET1 acts as an oncogene in ESCC and may represent a novel therapeutic target for the treatment of ESCC patients.


Author(s):  
Kristin Schirmer ◽  
Katrin Tanneberger ◽  
Nynke I. Kramer ◽  
Frans J.M. Busser ◽  
Joop L.M. Hermens ◽  
...  

Antioxidants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1894
Author(s):  
Marcelo Villagran ◽  
Jorge Ferreira ◽  
Miquel Martorell ◽  
Lorena Mardones

Vitamin C is a water-soluble antioxidant associated with the prevention of the common cold and is also a cofactor of hydrolases that participate in the synthesis of collagen and catecholamines, and in the regulation of gene expression. In cancer, vitamin C is associated with prevention, progression, and treatment, due to its general properties or its role as a pro-oxidant at high concentration. This review explores the role of vitamin C in cancer clinical trials and the aspects to consider in future studies, such as plasmatic vitamin C and metabolite excretion recording, and metabolism and transport of vitamin C into cancer cells. The reviewed studies show that vitamin C intake from natural sources can prevent the development of pulmonary and breast cancer, and that vitamin C synergizes with gemcitabine and erlotinib in pancreatic cancer. In vitro assays reveal that vitamin C synergizes with DNA-methyl transferase inhibitors. However, vitamin C was not associated with cancer prevention in a Mendelian randomized study. In conclusion, the role of vitamin C in the prevention and treatment of cancer is still an ongoing area of research. It is necessary that new phase II and III clinical trials be performed to collect stronger evidence of the therapeutic role of vitamin C in cancer.


2019 ◽  
Vol 16 (1) ◽  
Author(s):  
Violaine Sironval ◽  
Mihaly Palmai-Pallag ◽  
Rita Vanbever ◽  
François Huaux ◽  
Jorge Mejia ◽  
...  

Abstract Background Li-ion batteries (LIB) are increasingly used worldwide. They are made of low solubility micrometric particles, implying a potential for inhalation toxicity in occupational settings and possibly for consumers. LiCoO2 (LCO), one of the most used cathode material, induces inflammatory and fibrotic lung responses in mice. LCO also stabilizes hypoxia-inducible factor (HIF) -1α, a factor implicated in inflammation, fibrosis and carcinogenicity. Here, we investigated the role of cobalt, nickel and HIF-1α as determinants of toxicity, and evaluated their predictive value for the lung toxicity of LIB particles in in vitro assays. Results By testing a set of 5 selected LIB particles (LCO, LiNiMnCoO2, LiNiCoAlO2) with different cobalt and nickel contents, we found a positive correlation between their in vivo lung inflammatory activity, and (i) Co and Ni particle content and their bioaccessibility and (ii) the stabilization of HIF-1α in the lung. Inhibition of HIF-1α with chetomin or PX-478 blunted the lung inflammatory response to LCO in mice. In IL-1β deficient mice, HIF-1α was the upstream signal of the inflammatory lung response to LCO. In vitro, the level of HIF-1α stabilization induced by LIB particles in BEAS-2B cells correlated with the intensity of lung inflammation induced by the same particles in vivo. Conclusions We conclude that HIF-1α, stabilized in lung cells by released Co and Ni ions, is a mechanism-based biomarker of lung inflammatory responses induced by LIB particles containing Co/Ni. Documenting the Co/Ni content of LIB particles, their bioaccessibility and their capacity to stabilize HIF-1α in vitro can be used to predict the lung inflammatory potential of LIB particles.


2020 ◽  
Vol 21 (24) ◽  
pp. 9721
Author(s):  
Giuseppina Augimeri ◽  
Luca Gelsomino ◽  
Pierluigi Plastina ◽  
Cinzia Giordano ◽  
Ines Barone ◽  
...  

Multiple lines of evidence indicate that activation of the peroxisome proliferator-activated receptor γ (PPARγ) by natural or synthetic ligands exerts tumor suppressive effects in different types of cancer, including breast carcinoma. Over the past decades a new picture of breast cancer as a complex disease consisting of neoplastic epithelial cells and surrounding stroma named the tumor microenvironment (TME) has emerged. Indeed, TME is now recognized as a pivotal element for breast cancer development and progression. Novel strategies targeting both epithelial and stromal components are under development or undergoing clinical trials. In this context, the aim of the present review is to summarize PPARγ activity in breast TME focusing on the role of this receptor on both epithelial/stromal cells and extracellular matrix components of the breast cancer microenvironment. The information provided from the in vitro and in vivo research indicates PPARγ ligands as potential agents with regards to the battle against breast cancer.


2012 ◽  
Vol 442 (3) ◽  
pp. 621-629 ◽  
Author(s):  
Radin Sadre ◽  
Christian Pfaff ◽  
Stephan Buchkremer

PQ-9 (plastoquinone-9) has a central role in energy transformation processes in cyanobacteria by mediating electron transfer in both the photosynthetic as well as the respiratory electron transport chain. The present study provides evidence that the PQ-9 biosynthetic pathway in cyanobacteria differs substantially from that in plants. We identified 4-hydroxybenzoate as being the aromatic precursor for PQ-9 in Synechocystis sp. PCC6803, and in the present paper we report on the role of the membrane-bound 4-hydroxybenzoate solanesyltransferase, Slr0926, in PQ-9 biosynthesis and on the properties of the enzyme. The catalytic activity of Slr0926 was demonstrated by in vivo labelling experiments in Synechocystis sp., complementation studies in an Escherichia coli mutant with a defect in ubiquinone biosynthesis, and in vitro assays using the recombinant as well as the native enzyme. Although Slr0926 was highly specific for the prenyl acceptor substrate 4-hydroxybenzoate, it displayed a broad specificity with regard to the prenyl donor substrate and used not only solanesyl diphosphate, but also a number of shorter-chain prenyl diphosphates. In combination with in silico data, our results indicate that Slr0926 evolved from bacterial 4-hydroxybenzoate prenyltransferases catalysing prenylation in the course of ubiquinone biosynthesis.


Author(s):  
Steffen Pockes ◽  
Katharina Tropmann

Since the discovery of the histamine H2 receptor (H2R), radioligands were among the most powerful tools to investigate its role and function. Initially, radiolabeling was used to investigate human and rodent tissues regarding their receptor expression. Later, radioligands gained increasing significance as pharmacological tools in in vitro assays. Although tritium-labeling was mainly used for this purpose, labeling with carbon-14 is preferred for metabolic studies of drug candidates. After the more-or-less successful application of numerous labeled H2R antagonists, the recent development of the G protein-biased radioligand [3H]UR-KAT479 represents another step forward to elucidate the widely unknown role of the H2R in the central nervous system through future studies.


Author(s):  
Marco Giordano ◽  
Alessandra Decio ◽  
Chiara Battistini ◽  
Micol Baronio ◽  
Fabrizio Bianchi ◽  
...  

Abstract Background Cancer stem cells (CSC) have been implicated in tumor progression. In ovarian carcinoma (OC), CSC drive tumor formation, dissemination and recurrence, as well as drug resistance, thus contributing to the high death-to-incidence ratio of this disease. However, the molecular basis of such a pathogenic role of ovarian CSC (OCSC) has been elucidated only to a limited extent. In this context, the functional contribution of the L1 cell adhesion molecule (L1CAM) to OC stemness remains elusive. Methods The expression of L1CAM was investigated in patient-derived OCSC. The genetic manipulation of L1CAM in OC cells provided gain and loss-of-function models that were then employed in cell biological assays as well as in vivo tumorigenesis experiments to assess the role of L1CAM in OC cell stemness and in OCSC-driven tumor initiation. We applied antibody-mediated neutralization to investigate L1CAM druggability. Biochemical approaches were then combined with functional in vitro assays to study the molecular mechanisms underlying the functional role of L1CAM in OCSC. Results We report that L1CAM is upregulated in patient-derived OCSC. Functional studies showed that L1CAM promotes several stemness-related properties in OC cells, including sphere formation, tumor initiation and chemoresistance. These activities were repressed by an L1CAM-neutralizing antibody, pointing to L1CAM as a druggable target. Mechanistically, L1CAM interacted with and activated fibroblast growth factor receptor-1 (FGFR1), which in turn induced the SRC-mediated activation of STAT3. The inhibition of STAT3 prevented L1CAM-dependent OC stemness and tumor initiation. Conclusions Our study implicate L1CAM in the tumorigenic function of OCSC and point to the L1CAM/FGFR1/SRC/STAT3 signaling pathway as a novel driver of OC stemness. We also provide evidence that targeting this pathway can contribute to OC eradication.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3581-3581
Author(s):  
Nirav Dhanesha ◽  
Manasa K Nayak ◽  
Prakash Doddapattar ◽  
Anil K Chauhan

Background: Coordinated interactions between neutrophils, platelets and endothelial cells contribute towards the development of arterial thrombosis. Neutrophils along with platelets are the first immune cells that are recruited at the site of endothelial activation/injury or infection. Recent studies have suggested that neutrophils modulate thrombosis via several mechanisms, including NETosis (formation of neutrophil extracellular traps). The integrin α9 is highly expressed on neutrophils while platelets do not express it. The integrin α9 up-regulated upon neutrophil activation and is implicated in stable adhesion and transmigration. The mechanisms underlying the role of integrin α9 towards the progression of arterial thrombosis has not been explored yet. Objective: To elucidate the mechanistic insights into the role of myeloid-cell specific integrin α9 in neutrophil adhesion and arterial thrombosis. Methods: We generated novel myeloid-specific α9-/- mice (α9fl/fl LysMcre+l-) by crossing α9fl/fl with LysMcr+/+mice. Littermates α9fl/flLysMcre-l-mice were used as controls. Standardized in vitro assays were used to evaluate the role of integrin α9 in neutrophil mediated platelet aggregation, NETosis and Cathepsin-G release. Susceptibility to arterial thrombosis and hemostasis was evaluated in vivo (FeCl3-induced carotid and laser-injury induced mesenteric artery thrombosis models) by utilizing intravital microscopy and tail bleeding assay respectively. Results: α9fl/flLysMCre+/-mice developed smaller thrombi (~40% occlusion), when compared with α9fl/flmice (~80% occlusion, 10 minutes post-FeCl3 induced injury). The mean time to complete occlusion was significantly prolonged in α9fl/flLysMCre+/-mice (P<0.05 vs α9fl/fl mice). Consistent with this, α9fl/flLysMCre+/-mice displayed significantly decreased platelet mean fluorescence intensity (MFI) and reduced rate of thrombus growth in laser injury-induced thrombosis model (P<0.05 vs. α9fl/fl mice). Together, these results suggest that myeloid cell-specific integrin α9 contributes to the experimental thrombosis at arterial shear rates. Monocytes depletion experiments demonstrated a minimal role for monocyte in progression of arterial thrombosis. In vitro mechanistic studies demonstrated a reduction in neutrophil-mediated platelet aggregation and cathepsin-G secretion in myeloid cell-specific integrin α9-/- mice, when compared with litter-mates control wild-type mice. Notably, the percentage of cells releasing NETs was markedly reduced in myeloid cell-specific integrin α9-/- mice that was concomitant with reduced MPO levels in carotid thrombus of α9fl/flLysMCre+/-mice. Together, these results suggest most likely integrin α9 expressed on neutrophils, but not monocytes, promotes arterial thrombosis. Comparable tail bleeding time between α9fl/flLysMcreand littermate α9fl/fl mice suggested that myeloid-cell specific deficiency of integrin α9 does not alter hemostasis. Conclusion: These findings reveal a novel role for integrin α9 in modulation of arterial thrombosis. While the clinical implications of these findings remains to be explored, we suggest that targeting integrin α9 may reduce post reperfusion thrombo-inflammatory injury, following acute myocardial infarction or stroke. Disclosures No relevant conflicts of interest to declare.


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