299 research outputs found
Establishment of lal-/- myeloid lineage cell line that resembles myeloid-derived suppressive cells
Myeloid-derived suppressor cells (MDSCs) in mouse are inflammatory cells that play critical roles in promoting cancer growth and metastasis by directly stimulating cancer cell proliferation and suppressing immune surveillance. In order to facilitate characterization of biochemical and cellular mechanisms of MDSCs, it is urgent to establish an "MDSC-like" cell line. By cross breeding of immortomouse (simian virus 40 large T antigen transgenic mice) with wild type and lysosomal acid lipase (LAL) knock-out (lal-/-) mice, we have established a wild type (HD1A) and a lal-/- (HD1B) myeloid cell lines. Compared with HD1A cells, HD1B cells demonstrated many characteristics similar to lal-/- MDSCs. HD1B cells exhibited increased lysosomes around perinuclear areas, dysfunction of mitochondria skewing toward fission structure, damaged membrane potential, and increased ROS production. HD1B cells showed increased glycolytic metabolism during blockage of fatty acid metabolism to fuel the energy need. Similar to lal-/- MDSCs, the mTOR signal pathway in HD1B cells is overly activated. Rapamycin treatment of HD1B cells reduced ROS production and restored the mitochondrial membrane potential. HD1B cells showed much stronger immunosuppression on CD4+ T cell proliferation and function in vitro, and enhanced cancer cells proliferation. Knockdown of mTOR with siRNA reduced the HD1B cell ability to immunosuppress T cells and stimulate cancer cell proliferation. Therefore, the HD1B myeloid cell line is an "MDSC-like" cell line that can be used as an alternative in vitro system to study how LAL controls various myeloid cell functions
Transthyretin Stimulates Tumor Growth through Regulation of Tumor, Immune, and Endothelial Cells
Early detection of lung cancer offers an important opportunity to decrease mortality while it is still treatable and curable. Thirteen secretory proteins that are Stat3 downstream gene products were identified as a panel of biomarkers for lung cancer detection in human sera. This panel of biomarkers potentially differentiates different types of lung cancer for classification. Among them, the transthyretin (TTR) concentration was highly increased in human serum of lung cancer patients. TTR concentration was also induced in the serum, bronchoalveolar lavage fluid, alveolar type II epithelial cells, and alveolar myeloid cells of the CCSP-rtTA/(tetO)7-Stat3C lung tumor mouse model. Recombinant TTR stimulated lung tumor cell proliferation and growth, which were mediated by activation of mitogenic and oncogenic molecules. TTR possesses cytokine functions to stimulate myeloid cell differentiation, which are known to play roles in tumor environment. Further analyses showed that TTR treatment enhanced the reactive oxygen species production in myeloid cells and enabled them to become functional myeloid-derived suppressive cells. TTR demonstrated a great influence on a wide spectrum of endothelial cell functions to control tumor and immune cell migration and infiltration. TTR-treated endothelial cells suppressed T cell proliferation. Taken together, these 13 Stat3 downstream inducible secretory protein biomarkers potentially can be used for lung cancer diagnosis, classification, and as clinical targets for lung cancer personalized treatment if their expression levels are increased in a given lung cancer patient in the blood
Gene Profile of Myeloid-Derived Suppressive Cells from the Bone Marrow of Lysosomal Acid Lipase Knock-Out Mice
BACKGROUND: Lysosomal acid lipase (LAL) controls development and homeostasis of myeloid lineage cells. Loss of the lysosomal acid lipase (LAL) function leads to expansion of myeloid-derived suppressive cells (MDSCs) that cause myeloproliferative neoplasm. METHODOLOGY/PRINCIPAL FINDINGS: Affymetrix GeneChip microarray analysis identified detailed intrinsic defects in Ly6G(+) myeloid lineage cells of LAL knock-out (lal-/-) mice. Ingenuity Pathway Analysis revealed activation of the mammalian target of rapamycin (mTOR) signaling, which functions as a nutrient/energy/redox sensor, and controls cell growth, cell cycle entry, cell survival, and cell motility. Loss of the LAL function led to major alteration of large GTPase and small GTPase signal transduction pathways. lal-/- Ly6G(+) myeloid cells in the bone marrow showed substantial increase of cell proliferation in association with up-regulation of cyclin and cyclin-dependent kinase (cdk) genes. The epigenetic microenvironment was significantly changed due to the increased expression of multiple histone cluster genes, centromere protein genes and chromosome modification genes. Gene expression of bioenergetic pathways, including glycolysis, aerobic glycolysis, mitochondrial oxidative phosphorylation, and respiratory chain proteins, was also increased, while the mitochondrial function was impaired in lal-/- Ly6G(+) myeloid cells. The concentration of reactive oxygen species (ROS) was significantly increased accompanied by up-regulation of nitric oxide/ROS production genes in these cells. CONCLUSIONS/SIGNIFICANCE: This comprehensive gene profile study for the first time identifies and defines important gene pathways involved in the myeloid lineage cells towards MDSCs using lal-/- mouse model
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Optical biopsy identification and grading of gliomas using label-free visible resonance Raman spectroscopy.
Glioma is one of the most refractory types of brain tumor. Accurate tumor boundary identification and complete resection of the tumor are essential for glioma removal during brain surgery. We present a method based on visible resonance Raman (VRR) spectroscopy to identify glioma margins and grades. A set of diagnostic spectral biomarkers features are presented based on tissue composition changes revealed by VRR. The Raman spectra include molecular vibrational fingerprints of carotenoids, tryptophan, amide I/II/III, proteins, and lipids. These basic in situ spectral biomarkers are used to identify the tissue from the interface between brain cancer and normal tissue and to evaluate glioma grades. The VRR spectra are also analyzed using principal component analysis for dimension reduction and feature detection and support vector machine for classification. The cross-validated sensitivity, specificity, and accuracy are found to be 100%, 96.3%, and 99.6% to distinguish glioma tissues from normal brain tissues, respectively. The area under the receiver operating characteristic curve for the classification is about 1.0. The accuracies to distinguish normal, low grade (grades I and II), and high grade (grades III and IV) gliomas are found to be 96.3%, 53.7%, and 84.1% for the three groups, respectively, along with a total accuracy of 75.1%. A set of criteria for differentiating normal human brain tissues from normal control tissues is proposed and used to identify brain cancer margins, yielding a diagnostic sensitivity of 100% and specificity of 71%. Our study demonstrates the potential of VRR as a label-free optical molecular histopathology method used for in situ boundary line judgment for brain surgery in the margins
Irreversible dual inhibitory mode: the novel Btk inhibitor PLS-123 demonstrates promising anti-tumor activity in human B-cell lymphoma.
The B-cell receptor (BCR) signaling pathway has gained significant attention as a therapeutic target in B-cell malignancies. Recently, several drugs that target the BCR signaling pathway, especially the Btk inhibitor ibrutinib, have demonstrated notable therapeutic effects in relapsed/refractory patients, which indicates that pharmacological inhibition of BCR pathway holds promise in B-cell lymphoma treatment. Here we present a novel covalent irreversible Btk inhibitor PLS-123 with more potent anti-proliferative activity compared with ibrutinib in multiple cellular and in vivo models through effective apoptosis induction and dual-action inhibitory mode of Btk activation. The phosphorylation of BCR downstream activating AKT/mTOR and MAPK signal pathways was also more significantly reduced after treatment with PLS-123 than ibrutinib. Gene expression profile analysis further suggested that the different selectivity profile of PLS-123 led to significant downregulation of oncogenic gene PTPN11 expression, which might also offer new opportunities beyond what ibrutinib has achieved. In addition, PLS-123 dose-dependently attenuated BCR- and chemokine-mediated lymphoma cell adhesion and migration. Taken together, Btk inhibitor PLS-123 suggested a new direction to pharmacologically modulate Btk function and develop novel therapeutic drug for B-cell lymphoma treatment
PM2.5 Pollution and Inhibitory Effects on Industry Development: A Bidirectional Correlation Effect Mechanism
In this paper, a vector autoregression (VAR) model has been constructed in order to analyze a two-way mechanism between PM2.5 pollution and industry development in Beijing via the combination of an impulse response function and variance decomposition. According to the results, long-term equilibrium interconnection was found between PM2.5 pollution and the development of primary, secondary, and tertiary industries. One-way Granger causalities were found in the three types of industries shown to contribute to PM2.5 pollution, though the three industries showed different scales of influences on the PM2.5 pollution that varied for about 1–2 years. The development of the primary and secondary industries increased the emission of PM2.5, but the tertiary industry had an inhibitory effect. In addition, PM2.5 pollution had a certain inhibitory effect on the development of the primary and secondary industries, but the inhibition of the tertiary industry was not significant. Therefore, the development of the tertiary industry can contribute the most to the reduction of PM2.5 pollution. Based on these findings, policy-making recommendations can be proposed regarding upcoming pollution prevention strategies
PM2.5 Pollution: Health and Economic Effect Assessment Based on a Recursive Dynamic Computable General Equilibrium Model
At present particulate matter (PM₂.₅) pollution represents a serious threat to the public health and the national economic system in China. This paper optimizes the whitening coefficient in a grey Markov model by a genetic algorithm, predicts the concentration of fine particulate matter (PM₂.₅), and then quantifies the health effects of PM₂.₅ pollution by utilizing the predicted concentration, computable general equilibrium (CGE), and a carefully designed exposure–response model. Further, the authors establish a social accounting matrix (SAM), calibrate the parameter values in the CGE model, and construct a recursive dynamic CGE model under closed economy conditions to assess the long-term economic losses incurred by PM₂.₅ pollution. Subsequently, an empirical analysis was conducted for the Beijing area: Despite the reduced concentration trend, PM₂.₅ pollution continued to cause serious damage to human health and the economic system from 2013 to 2020, as illustrated by various facts, including: (1) the estimated premature deaths and individuals suffering haze pollution-related diseases are 156,588 (95% confidence intervals (CI): 43,335–248,914)) and six million, respectively; and (2) the accumulated labor loss and the medical expenditure negatively impact the regional gross domestic product, with an estimated loss of 3062.63 (95% CI: 1,168.77–4671.13) million RMB. These findings can provide useful information for governmental agencies to formulate relevant environmental policies and for communities to promote prevention and rescue strategies
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