Mapping the immune microenvironment for mandibular alveolar bone homeostasis at single-cell resolution.
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ABSTRACT:
SUBMITTER: Lin W
PROVIDER: S-EPMC7960742 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:BackgroundNasopharyngeal carcinoma (NPC) is an assertive malignancy with partially understood underlying mechanisms, urging further study into its diverse and dynamic tumor microenvironment (TME) to bolster diagnosis, treatment, and prognostic accuracy.AimsTo track the evolutionary route of metastasis, here we perform a yielding scRNA-seq data from 24 primary carcinoma, 7 peripheral blood mononuclear cell (PBMC) nasopharyngeal carcinoma, and 7 metastatic carcinoma patients' sample.Materials and methodsFollowing high quality control and filtration, a total of 292,298 cells from these tumors were classified into 10 clusters: T cells, B cells, Macrophages/Monocytes, Natural Killer (NK) cells, Plasma cells, plasmacytoid Dendritic Cells, Migratory Dendritic Cells, Mast cells, Cancer-Associated Fibroblasts, and Epithelial cells.ResultsBy comparing and analyzing the different functional capacities of cellular entities within primary and metastatic nasopharyngeal carcinoma, coupled with a detailed investigation into the heterogeneity and differential fate trajectories of T cells, B cells, and myeloid cells, as well as assessing the interactions of cell-cell communicative heterogeneity between these carcinogenic states, we established single-cell atlases for primary and metastatic tumors and identified a large number of potential therapeutic targets.ConclusionThis comprehensive analysis significantly advances our understanding of nasopharyngeal carcinoma (NPC) metastasis by detailing the evolutionary dynamics and the impact of the tumor microenvironment at a single-cell resolution, thereby laying a crucial foundation for future metastatic tumor research and providing new insights into immune heterogeneity, molecular interactions, and potential therapeutic strategies for NPC.
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Project description:AimTo investigate the effect of genistein on bone homeostasis in mandibular subchondral bone of rats.MethodsFemale SD rats were administered with genistein (10 and 50 mg/kg) or placebo by oral gavage for 6 weeks. Then the animals were sacrificed, and histomorphology and micro-structure of mandibular condyle were examined using HE staining and micro-CT analysis, respectively. The expression levels of alkaline phosphatase (ALP), osteocalcin (OC), osteoprotegerin (OPG), the receptor activator of nuclear factor κB ligand (RANKL) and estrogen receptors (ERs) in mandibular condyle were detected using real-time PCR. Cultured osteoblasts were prepared from rat mandibular condyle for in in vitro study. The cells were treated with genistein (10(-7) or 10(-4) mol/L) for 48 h. The expression of the bone homeostasis-associated factors and estrogen receptors (ERs) was detected using real-time PCR, and ER silencing was performed.ResultsAt both the low- and high-doses, genistein significantly increased the bone mineral density (BMD) and bone volume, and resulted in thicker subchondral trabecular bone in vivo. In both in vivo and in vitro study, the low-dose genistein significantly increased the expression of ALP, OC and OPG, but decreased the expression of RANKL and the RANKL/OPG ratio. The high-dose genistein decreased the expression of all these bone homeostasis-associated factors. Both the low and high doses of genistein significantly increased the expression of ERβ, while ERα expression was increased by the low dose genistein and decreased by the high dose genistein. ERβ silencing abrogated most of the effects of genistein treatment.ConclusionIn rat mandibular condylar subchondral bone, low-dose genistein increases bone formation and inhibit bone resorption, while excess genistein inhibits both bone formation and resorption. The effects of genistein were predominantly mediated through ERβ.
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Project description:BACKGROUND:Mass cytometry leverages inductively coupled mass spectrometry to perform high dimensional single cell analyses using antibodies tagged with rare earth isotopes that are considered to be largely absent in biological samples. We have recently noted an unusual exception to this rule while analyzing tissue samples from patients undergoing surgical resection for early stage lung cancer, and here we present a detailed cytometric characterization of cerium in a clinical patient sample. METHODS:We performed a CyTOF analysis on cell suspensions derived from matched blood, tumor lesion, and non-involved lung tissue from an active smoker undergoing surgical resection for early stage lung adenocarcinoma. The samples were stained with a 31-parameter antibody panel to allow a detailed characterization of the cellular heterogeneity of the samples. The data were visualized using viSNE, major immune subsets were identified based on canonical marker expression patterns, and single cell cerium levels were evaluated across each of these defined subsets. RESULTS:High dimensional immune cell mapping revealed that high levels of cerium were specifically associated with a phenotypically distinct subset of lung macrophages that were most prevalent in noninvolved lung tissue, whereas tumor associated macrophages showed relatively lower levels of cerium. We hypothesize that these findings reflect alveolar macrophage phagocytosis of inhaled cerium derived from cigarette flint lighters. CONCLUSIONS:These results demonstrate the first high-dimensional single cell characterization of environmental metal exposure associated with smoking, and offer a demonstration of the unique potential for applying mass cytometry to the field of environmental toxicology. © 2017 International Clinical Cytometry Society.
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