Single-cell exome sequencing reveals single-nucleotide mutation characteristics of a kidney tumor.

Clear cell renal cell carcinoma (ccRCC) is the most common kidney cancer and has very few mutations that are shared between different patients. To better understand the intratumoral genetics underlying mutations of ccRCC, we carried out single-cell exome sequencing on a ccRCC tumor and its adjacent kidney tissue. Our data indicate that this tumor was unlikely to have resulted from mutations in VHL and PBRM1. Quantitative population genetic analysis indicates that the tumor did not contain any significant clonal subpopulations and also showed that mutations that had different allele frequencies within the population also had different mutation spectrums. Analyses of these data allowed us to delineate a detailed intratumoral genetic landscape at a single-cell level. Our pilot study demonstrates that ccRCC may be more genetically complex than previously thought and provides information that can lead to new ways to investigate individual tumors, with the aim of developing more effective cellular targeted therapies.

Single-cell transcriptomics of LepR-positive skeletal cells reveals heterogeneous stress-dependent stem and progenitor pools.

Leptin receptor (LepR)-positive cells are key components of the bone marrow hematopoietic microenvironment, and highly enrich skeletal stem and progenitor cells that maintain homeostasis of the adult skeleton. However, the heterogeneity and lineage hierarchy within this population has been elusive. Using genetic lineage tracing and single-cell RNA sequencing, we found that Lepr-Cre labels most bone marrow stromal cells and osteogenic lineage cells in adult long bones. Integrated analysis of Lepr-Cre-traced cells under homeostatic and stress conditions revealed dynamic changes of the adipogenic, osteogenic, and periosteal lineages. Importantly, we discovered a Notch3+ bone marrow sub-population that is slow-cycling and closely associated with the vasculatures, as well as key transcriptional networks promoting osteo-chondrogenic differentiation. We also identified a Sca-1+ periosteal sub-population with high clonogenic activity but limited osteo-chondrogenic potential. Together, we mapped the transcriptomic landscape of adult LepR+ stem and progenitor cells and uncovered cellular and molecular mechanisms underlying their maintenance and lineage specification.

Bone marrow-derived IGF-1 orchestrates maintenance and regeneration of the adult skeleton.

Insulin-like growth factor I (IGF-1) is a key regulator of tissue growth and development in response to growth hormone stimulation. In the skeletal system, IGF-1 derived from osteoblasts and chondrocytes are essential for normal bone development; however, whether bone marrow (BM)-resident cells provide distinct sources of IGF-1 in the adult skeleton remains elusive. Here, we show that BM stromal cells (BMSCs) and megakaryocytes/platelets (MKs/PLTs) express the highest levels of IGF-1 in adult long bones. Deletion of Igf1 from BMSCs by Lepr-Cre leads to decreased bone formation, impaired bone regeneration, and increased BM adipogenesis. Importantly, reduction of BMSC-derived IGF-1 contributes to fasting-induced marrow fat accumulation. In contrast, deletion of Igf1 from MKs/PLTs by Pf4-Cre leads to reduced bone formation and regeneration without affecting BM adipogenesis. To our surprise, MKs/PLTs are also an important source of systemic IGF-1. Platelet-rich plasma (PRP) from Pf4-Cre; Igf1f/fmice showed compromised osteogenic potential both in vivo and in vitro, suggesting that MK/PLT-derived IGF-1 underlies the therapeutic effects of PRP. Taken together, this study identifies BMSCs and MKs/PLTs as two important sources of IGF-1 that coordinate to maintain and regenerate the adult skeleton, highlighting reciprocal regulation between the hematopoietic and skeletal systems.

Inhibition of Fap Promotes Cardiac Repair by Stabilizing BNP.

BACKGROUND: Myocardial infarction (MI) elicits cardiac fibroblast activation and extracellular matrix (ECM) deposition to maintain the structural integrity of the heart. Recent studies demonstrate that Fap (fibroblast activation protein)-a prolyl-specific serine protease-is an important marker of activated cardiac fibroblasts after MI. METHODS: Left ventricle and plasma samples from patients and healthy donors were used to analyze the expression level of FAP and its prognostic value. Echocardiography and histological analysis of heart sections were used to analyze cardiac functions, scar formation, ECM deposition and angiogenesis after MI. RNA-Sequencing, biochemical analysis, cardiac fibroblasts (CFs) and endothelial cells co-culture were used to reveal the molecular and cellular mechanisms by which Fap regulates angiogenesis. RESULTS: We found that Fap is upregulated in patient cardiac fibroblasts after cardiac injuries, while plasma Fap is downregulated and functions as a prognostic marker for cardiac repair. Genetic or pharmacological inhibition of Fap in mice significantly improved cardiac function after MI. Histological and transcriptomic analyses showed that Fap inhibition leads to increased angiogenesis in the peri-infarct zone, which promotes ECM deposition and alignment by cardiac fibroblasts and prevents their overactivation, thereby limiting scar expansion. Mechanistically, we found that BNP (brain natriuretic peptide) is a novel substrate of Fap that mediates postischemic angiogenesis. Fap degrades BNP to inhibit vascular endothelial cell migration and tube formation. Pharmacological inhibition of Fap in Nppb (encoding pre-proBNP) or Npr1 (encoding the BNP receptor)-deficient mice showed no cardioprotective effects, suggesting that BNP is a physiological substrate of Fap. CONCLUSIONS: This study identifies Fap as a negative regulator of cardiac repair and a potential drug target to treat MI. Inhibition of Fap stabilizes BNP to promote angiogenesis and cardiac repair.

Integrated MicroRNA and Secretome Analysis of Human Endometrial Organoids Reveal the miR-3194-5p/Aquaporin/S100A9 Module in Regulating Trophoblast Functions.

Successful placentation requires delicate communication between the endometrium and trophoblasts. The invasion and integration of trophoblasts into the endometrium during early pregnancy are crucial to placentation. Dysregulation of these functions is associated with various pregnancy complications, such as miscarriage and preeclampsia. The endometrial microenvironment has an important influence on trophoblast cell functions. The precise effect of the endometrial gland secretome on trophoblast functions remains uncertain. We hypothesized that the hormonal environment regulates the miRNA profile and secretome of the human endometrial gland, which subsequently modulates trophoblast functions during early pregnancy. Human endometrial tissues were obtained from endometrial biopsies with written consent. Endometrial organoids were established in matrix gel under defined culture conditions. They were treated with hormones mimicking the environment of the proliferative phase (Estrogen, E2), secretory phase (E2+Progesterone, P4), and early pregnancy (E2+P4+Human Chorionic Gonadotropin, hCG). miRNA-seq was performed on the treated organoids. Organoid secretions were also collected for mass spectrometric analysis. The viability and invasion/migration of the trophoblasts after treatment with the organoid secretome were determined by cytotoxicity assay and transwell assay, respectively. Endometrial organoids with the ability to respond to sex steroid hormones were successfully developed from human endometrial glands. By establishing the first secretome profiles and miRNA atlas of these endometrial organoids to the hormonal changes followed by trophoblast functional assays, we demonstrated that sex steroid hormones modulate aquaporin (AQP)1/9 and S100A9 secretions through miR-3194 activation in endometrial epithelial cells, which in turn enhanced trophoblast migration and invasion during early pregnancy. By using a human endometrial organoid model, we demonstrated for the first time that the hormonal regulation of the endometrial gland secretome is crucial to regulating the functions of human trophoblasts during early pregnancy. The study provides the basis for understanding the regulation of early placental development in humans.

Unraveling the rapid ion migration in perovskite solar cells by circuit-switched transient photoelectric technique.

Ion migration activated by illumination is a critical factor responsible for the performance decline and stability degradation of perovskite solar cells (PSCs). While ion migration has been widely believed to be much slower than charge transport, recent research suggests that, despite the lack of understanding of the mechanism, it may also be involved in a series of rapid photoelectric responses of PSCs. Here, we report an improved circuit-switched transient photoelectric technique with nanosecond temporal resolution, which enables quantitative characterization of ion migration dynamics in PSCs across a fairly broad time window. Specifically, ion migration occurring within microseconds after illumination (corresponding to a diffusion length of ∼10-7 cm) is unambiguously identified. In conjunction with the composition engineering protocol, we justify that it arises from the short-range migration of halide anions and organic cations around the contact/perovskite interface. The rapid ion migration kinetics revealed in this work strongly complement the well-established ion migration model, which offers new insights into the mechanism of ion-carrier interaction in PSC devices.

The male germline-specific protein MAPS is indispensable for pachynema progression and fertility.

Meiosis is a specialized cell division that creates haploid germ cells from diploid progenitors. Through differential RNA expression analyses, we previously identified a number of mouse genes that were dramatically elevated in spermatocytes, relative to their very low expression in spermatogonia and somatic organs. Here, we investigated in detail 1700102P08Rik, one of these genes, and independently conclude that it encodes a male germline-specific protein, in agreement with a recent report. We demonstrated that it is essential for pachynema progression in spermatocytes and named it male pachynema-specific (MAPS) protein. Mice lacking Maps (Maps-/- ) suffered from pachytene arrest and spermatocyte death, leading to male infertility, whereas female fertility was not affected. Interestingly, pubertal Maps-/- spermatocytes were arrested at early pachytene stage, accompanied by defects in DNA double-strand break (DSB) repair, crossover formation, and XY body formation. In contrast, adult Maps-/- spermatocytes only exhibited partially defective crossover but nonetheless were delayed or failed in progression from early to mid- and late pachytene stage, resulting in cell death. Furthermore, we report a significant transcriptional dysregulation in autosomes and XY chromosomes in both pubertal and adult Maps-/- pachytene spermatocytes, including failed meiotic sex chromosome inactivation (MSCI). Further experiments revealed that MAPS overexpression in vitro dramatically decreased the ubiquitination levels of cellular proteins. Conversely, in Maps-/- pachytene cells, protein ubiquitination was dramatically increased, likely contributing to the large-scale disruption in gene expression in pachytene cells. Thus, MAPS is a protein essential for pachynema progression in male mice, possibly in mammals in general.

Single-cell characterization of self-renewing primary trophoblast organoids as modeling of EVT differentiation and interactions with decidual natural killer cells.

BACKGROUND: Extravillous trophoblast cell (EVT) differentiation and its communication with maternal decidua especially the leading immune cell type natural killer (NK) cell are critical events for placentation. However, appropriate in vitro modelling system and regulatory programs of these two events are still lacking. Recent trophoblast organoid (TO) has advanced the molecular and mechanistic research in placentation. Here, we firstly generated the self-renewing TO from human placental villous and differentiated it into EVTs (EVT-TO) for investigating the differentiation events. We then co-cultured EVT-TO with freshly isolated decidual NKs for further study of cell communication. TO modelling of EVT differentiation as well as EVT interaction with dNK might cast new aspect for placentation research. RESULTS: Single-cell RNA sequencing (scRNA-seq) was applied for comprehensive characterization and molecular exploration of TOs modelling of EVT differentiation and interaction with dNKs. Multiple distinct trophoblast states and dNK subpopulations were identified, representing CTB, STB, EVT, dNK1/2/3 and dNKp. Lineage trajectory and Seurat mapping analysis identified the close resemblance of TO and EVT-TO with the human placenta characteristic. Transcription factors regulatory network analysis revealed the cell-type specific essential TFs for controlling EVT differentiation. CellphoneDB analysis predicted the ligand-receptor complexes in dNK-EVT-TO co-cultures, which relate to cytokines, immunomodulation and angiogenesis. EVT was known to affect the immune properties of dNK. Our study found out that on the other way around, dNKs could exert effects on EVT causing expression changes which are functionally important. CONCLUSION: Our study documented a single-cell atlas for TO and its applications on EVT differentiation and communications with dNKs, and thus provide methodology and novel research cues for future study of human placentation.

PUMILIO-mediated translational control of somatic cell cycle program promotes folliculogenesis and contributes to ovarian cancer progression.

Translational control is a fundamental mechanism regulating animal germ cell development. Gonadal somatic cells provide support and microenvironment for germ cell development to ensure fertility, yet the roles of translational control in gonadal somatic compartment remain largely undefined. We found that mouse homolog of conserved fly germline stem cell factor Pumilio, PUM1, is absent in oocytes of all growing follicles after the primordial follicle stage, instead, it is highly expressed in somatic compartments of ovaries. Global loss of Pum1, not oocyte-specific loss of Pum1, led to a significant reduction in follicular number and size as well as fertility. Whole-genome identification of PUM1 targets in ovarian somatic cells revealed an enrichment of cell proliferation pathway, including 48 key regulators of cell phase transition. Consistently granulosa cells proliferation is reduced and the protein expression of the PUM-bound Cell Cycle Regulators (PCCR) were altered accordingly in mutant ovaries, and specifically in granulosa cells. Increase in negative regulator expression and decrease in positive regulators in the mutant ovaries support a coordinated translational control of somatic cell cycle program via PUM proteins. Furthermore, postnatal knockdown, but not postnatal oocyte-specific loss, of Pum1 in Pum2 knockout mice reduced follicular growth and led to similar expression alteration of PCCR genes, supporting a critical role of PUM-mediated translational control in ovarian somatic cells for mammalian female fertility. Finally, expression of human PUM protein and its regulated cell cycle targets exhibited significant correlation with ovarian cancer and prognosis for cancer survival. Hence, PUMILIO-mediated cell cycle regulation represents an important mechanism in mammalian female reproduction and human cancer biology.

Hesperetin attenuates cognitive dysfunction via SIRT6/NLRP3 pathway in scopolamine-induced mice.

Neuroinflammation is a critical feature in the pathogenesis of neurodegenerative disorders such as Alzheimer's disease (AD). Hesperetin can exert anti-inflammatory, antioxidant and other neuroprotective effects. In this study, the scopolamine (SCOP)-induced cognitive dysfunction in mice model was used to evaluate the neuroprotective effects of hesperetin. Behavioral tests (Morris water maze, open field, and novel object recognition tests) were conducted to evaluate the effect of hesperetin on cognitive dysfunction behaviors. Nissl staining and Immunofluorescence were used to evaluate hippocampal neuronal damage and microglial activation in mice. The levels of proinflammatory factors, oxidant stress, and the cholinergic neurotransmitter were detected by real-time quantitative fluorescence PCR (RT-qPCR) or biochemical reagent kits. Western blotting was used to detect the relative protein expression of the sirtuin 6 (SIRT6) / NOD-like receptor thermal protein domain associated protein 3 (NLRP3) pathway. Results showed that hesperetin could ameliorate SCOP-induced cognitive impairment and neuronal damage, and regulate the levels of cholinergic neurotransmitters in the hippocampal of AD mice. Hesperetin could also enhance antioxidant defense by regulating the levels of reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT). Hesperetin exerted anti-neuroinflammation effects through inhibiting of microglia activation and down-regulating the mRNA transcript levels of inflammatory cytokines, such as tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), interleukin-1ß (IL-1ß), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS). Meanwhile, hesperetin could attenuate the expression of NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC), thioredoxin-interacting protein (TXNIP), and caspase-1 p20 and upregulate the expression of SIRT6 in SCOP-induced mice. Overall, our study suggested that hesperetin might ameliorate SCOP-induced cognitive dysfunction by improving cholinergic system dysfunction and suppressing oxidative stress and attenuating neuroinflammation via SIRT6/NLRP3 pathway in mice.

Preparation and evaluation of attractive microspheres for control of Agrilus planipennis fairmaire.

Agrilus planipennis Fairmaire is an important wood boring pest of Fraxinus species in the family Oleaceae. Oxacyclotridecan-2-one is an attractant of A. planipennis. Traps with attractive lures can be used in mass trapping of insect pests, but the traps are a bit expensive and they must be set up and dismantled in the field. To develop an attract and kill method for A. planipennis, we enveloped oxacyclotridecan-2-one into sustained-released microspheres. The attractant microspheres were prepared using the solvent evaporation method. An orthogonal test L16(45) was used to optimize the five preparation factors: the quantities of polylactic acid (PLA), gelatin, Polyvinyl alcohol (PVA), attractant, and the rotational speed. The results showed that optimal conditions for preparation of microspheres were 2.5 g PLA, 0.5 g gelatin, 1.25 g PVA, 2 mL attractant and 600 r min-1 rotational speed. The encapsulation efficiency of the prepared microspheres was 95.22%, and the attractant loading rate was 15.61%. The release rate of attractant from prepared microspheres was about 26.74% on the first day, and then gradually entered a sustained-release stage for about 10 days that lasted for 17 days. Preliminary field control experiments showed that the prepared microspheres could attract and kill A. planipennis adults when sprayed together with insecticide.

Sertoli cell PUMILIO proteins modulate mouse testis size through translational control of cell cycle regulators.

Testis size determination is an important question of reproductive biology. Sertoli cells are known to be a key determinant of mammalian testis size but the underlying molecular mechanisms remain incompletely understood. Previously we showed that highly conserved germ cell RNA-binding proteins, PUMILIO1(PUM1) and PUMILIO2 (PUM2), control mouse organ and body size through translational regulation, but how different cell types of the organs contribute to their organ size regulation has not been established. Here, we report a somatic role of PUM in gonad size determination. PUM1 is highly expressed in the Sertoli cells of the developing testis from embryonic and postnatal mice as well as in germ cells. Removal of Sertoli cell, but not germ cell, Pum1 gene, led to reduced testis size without significantly affecting sperm number or fertility. Knockout of PUM1 target, Cdkn1b, rescued the phenotype of reduced testis size, supporting a key role of Sertoli cell PUM1 mediated Cdkn1b repression in the testis size control. Furthermore, removal of Pum2 or both Pum1 and Pum2 in the Sertoli cells also only affected the testis size, not sperm development, with the biggest size reduction in Pum1/2 double knockout mice. We propose that PUM1 and PUM2 modulate the testis size through their synergistic translational regulation of cell cycle regulators in the Sertoli cell. Further investigation of the ovary or other organs could reveal if PUM-mediated translational control of cell proliferation of the supporting cell represents a general mechanism for organ size modulation.

Human placental exosomes induce maternal systemic immune tolerance by reprogramming circulating monocytes.

BACKGROUND: The maternal immune system needs to tolerate the semi-allogeneic fetus in pregnancy. The adaptation occurs locally at the maternal-fetal interface as well as systemically through the maternal circulation. Failure to tolerate the paternal antigens may result in pregnancy complications, such as pregnancy loss and pre-eclampsia. However, the mechanism that regulates maternal immune tolerance, especially at the systemic level, is still an enigma. Here we report that the first-trimester placenta-derived exosomes (pEXOs) contribute to maternal immune tolerance by reprogramming the circulating monocytes. RESULTS: pEXOs predominantly target monocytes and pEXO-educated monocytes exhibit an immunosuppressive phenotype as demonstrated by reduced expression of marker genes for monocyte activation, T-cell activation and antigen-process/presentation at the transcriptomic level. They also have a greater propensity towards M2 polarization when compared to the monocytes without pEXO treatment. The inclusion of pEXOs in a monocyte-T-cell coculture model significantly reduces proliferation of the T helper cells and cytotoxic T cells and elevates the expansion of regulatory T cells. By integrating the microRNAome of pEXO and the transcriptomes of pEXO-educated monocytes as well as various immune cell functional assays, we demonstrate that the pEXO-derived microRNA miR-29a-3p promotes the expression of programmed cell death ligand-1, a well-known surface receptor that suppresses the adaptive immune system, by down-regulation of phosphatase and tensin homolog in monocytes. CONCLUSIONS: This is the first report to show how human pEXO directly regulates monocyte functions and its molecular mechanism during early pregnancy. The results uncover the importance of pEXO in regulating the maternal systemic immune response during early pregnancy by reprogramming circulating monocytes. The study provides the basis for understanding the regulation of maternal immune tolerance to the fetal allograft.

Single-Cell RNA-Sequencing Reveals Interactions between Endometrial Stromal Cells, Epithelial Cells, and Lymphocytes during Mouse Embryo Implantation.

The decidualization of endometrial stromal cells (ESCs) is an essential process facilitating embryo implantation. However, the roles of non-decidualized and decidualized ESCs in regulating the microenvironment of a receptive endometrium remain unclear. We investigated single-cell transcriptomic changes in the uterus of a CD-1 mouse model at the post-implantation stage. The implantation and inter-implantation sites of the uteruses of pregnant mice at 4.5 and 5.5 days post-coitum were dissected for single-cell RNA sequencing. We identified eight cell types: epithelial cells, stromal cells, endothelial cells, mesothelial cells, lymphocytes, myocytes, myeloids, and pericytes. The ESC transcriptome suggests that the four ESC subtypes are involved in the extracellular remodeling during implantation. The trajectory plot of ESC subtypes indicates embryo implantation that involves a differentiation pathway from undifferentiated ESCs (ESC 1) to decidualized ESCs (DEC ESCs), with distinct signaling pathways between the ESC subtypes. Furthermore, the ligand-receptor analysis suggests that ESCs communicate with epithelial cells and immune cells through nectin and ICAM signaling. Collectively, both decidualized and non-decidualized ESCs may regulate the endometrial microenvironment for optimal endometrial receptivity and immune tolerance. This study provides insights on the molecular and cellular characteristics of mouse ESCs in modulating the epithelial and lymphocyte functions during early embryo implantation.

A pathogenic DMC1 frameshift mutation causes nonobstructive azoospermia but not primary ovarian insufficiency in humans.

Nonobstructive azoospermia (NOA) and diminished ovarian reserve (DOR) are two disorders that can lead to infertility in males and females. Genetic factors have been identified to contribute to NOA and DOR. However, the same genetic factor that can cause both NOA and DOR remains largely unknown. To explore the candidate pathogenic gene that causes both NOA and DOR, we conducted whole-exome sequencing (WES) in a non-consanguineous family with two daughters with DOR and a son with NOA. We detected one pathogenic frameshift variant (NM_007068:c.28delG, p. Glu10Asnfs*31) following a recessive inheritance mode in a meiosis gene DMC1 (DNA meiotic recombinase 1). Clinical analysis showed reduced antral follicle number in both daughters with DOR, but metaphase II oocytes could be retrieved from one of them. For the son with NOA, no spermatozoa were found after microsurgical testicular sperm extraction. A further homozygous Dmc1 knockout mice study demonstrated total failure of follicle development and spermatogenesis. These results revealed a discrepancy of DMC1 action between mice and humans. In humans, DMC1 is required for spermatogenesis but is dispensable for oogenesis, although the loss of function of this gene may lead to DOR. To our knowledge, this is the first report on the homozygous frameshift mutation as causative for both NOA and DOR and demonstrating that DMC1 is dispensable in human oogenesis.

MicroRNA-1 facilitates hypoxia-induced injury by targeting NOTCH3.

Cell proliferation, apoptosis, and autophagy have been reported to be related to myocardial ischemia injury. MicroRNAs have attracted wide attention on regulating cell proliferation, apoptosis, and autophagy. miR-1 expression has been reported to be dysregulated in cardiac tissue or cells with hypoxia, while the exact roles as well as underlying mechanism remain poorly understood. In this study, we investigated the potential roles of miR-1 in cell proliferation, apoptosis, and autophagy in hypoxia-treated cardiac injury and explored the underlying mechanism using H9c2 cells. Results showed that hypoxic stimulation inhibited cell proliferation and the expression of miR-1 but promoted cell apoptosis in H9c2 cells. Moreover, overexpression of miR-1 promoted cell apoptosis and inhibited cell proliferation and autophagy in H9c2 cells treated with hypoxia, while its knockdown played an opposite effect. In addition, bioinformatics, luciferase reporter, and RNA immunoprecipitation analyses indicated that NOTCH3 was a direct target of miR-1 and its upregulation reversed the effects of miR-1 on cell proliferation, apoptosis, and autophagy in hypoxia-treated H9c2 cells. Taken together, our data suggested that miR-1 promoted hypoxia-induced injury by targeting NOTCH3, indicating novel therapeutic targets for treatment of myocardial ischemia injury.

DLL3 is regulated by LIN28B and miR-518d-5p and regulates cell proliferation, migration and chemotherapy response in advanced small cell lung cancer.

Delta-like protein 3 (DLL3) has been reported as a biomarker in various human tumors. However, the biological function and mechanism of it in advanced small cell lung cancer (SCLC) is rarely reported. This study was devised innovatively to explore the role of DLL3 in the progression of SCLC. Immunohistochemistry (IHC) analysis was used to examine DLL3 expression in paraffin-embedded SCLC tumor samples. Upregulation of DLL3 reduced chemotherapy sensitivity. Kaplan-Meier analysis was used to analyze the progression-free survival or overall survival of SCLC patients with high or low level of DLL3. The negative association between DLL3 expression and the PFS or OS rate of SCLC patients was identified. Relative high level of DLL3 was determined in SCLC cell lines by using qRT-PCR analysis. Loss-of function assays were performed to detect the biological functions of the silencing of DLL3 in SCLC. As a result, silencing of DLL3 led to the proliferative and migratory inhibition of SCLC cells and reversed EMT process. Mechanistically, DLL3 mRNA was stabilized by the RNA-binding protein lin-28 homolog B (LIN28B). Further mechanism investigation revealed that LIN28B and DLL3 are two downstream targets of miR-518d-5p. Finally, rescue assays demonstrated that LIN28B and miR-518d-5p could regulate DLL3-mediated cell proliferation and migration. Collectively, our present study revealed a novel molecular pathway in SCLC, which providing a new insight in exploring the therapeutic strategy for SCLC.

Occurrence and Human Exposure Assessment of Short- and Medium-Chain Chlorinated Paraffins in Dusts from Plastic Sports Courts and Synthetic Turf in Beijing, China.

This study presents the first investigation of concentrations and congener group patterns of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) in 159 dust samples from plastic sports courts and synthetic turf in Beijing, China. The geometric mean concentration of SCCPs and MCCPs in dusts from plastic tracks (5429 and 15157 µg g-1) and basketball courts (5139 and 11878 µg g-1) were significantly higher than those from plastic tennis courts, badminton courts, and synthetic turf; meanwhile, they were 1-3 orders of magnitude higher than in dusts from other indoor environments. The friction between sneaker soles and plastic track materials may lead to the wear and decomposition of rubber, which may be an important source of chlorinated paraffins (CPs) in the dust from plastic tracks. The mean estimated daily intakes of CPs from plastic tracks and basketball courts are generally higher than those estimated from dietary, breast milk, or other indoor dust sources. The margin of exposure for adults and children was greater than 1000 both at mean and high-exposure scenarios, indicating that no significant health risks were posed by CPs in the dust from plastic sports courts and synthetic turf.

Presence and human exposure assessment of organophosphate flame retardants (OPEs) in indoor dust and air in Beijing, China.

In this study, levels of 14 organophosphate flame retardants (OPEs) were measured in 101 indoor dust samples collected from dormitories, residential homes, and offices in Beijing, China. In addition, paired air samples were also analyzed to evaluate any correlation between OPE levels in air and that in corresponding dust samples. The Σ14OPEs levels substantially varied between individual samples. Thereinto, significantly higher OPE levels were found in dust samples from office (mean value: 14 µg g-1), comparing to that in dust samples from residential homes (mean value: 5.9 µg g-1) and dormitories (mean value: 6.9 µg g-1). Congener profiles of OPEs in dust samples from different microenvironments indicated that tris (2-chloroethyl) phosphate (TCEP) was the dominant OPE in the office samples, followed by tris (2-chloroisopropyl) phosphate (TCPP). In contrast, TCPP was the dominant OPE in the residential home and dormitory samples, followed by TCEP. The mean concentration (range) of Σ14OPEs in the 15 air samples was 5.2 (1.0-20) ng m-3, and TCPP was the dominated congener in these samples. The concentration of TCEP and TCPP in air was positively correlated with that in corresponding indoor dust, and OPEs with highly saturated vapor pressures have higher fractions in the air than that in the dust. The estimated daily intakes through dust ingestion, dermal absorption, and inhalation indicated that the exposure to OPEs in indoor environments do not result in significant health risk for the general population in Beijing.

Acute and Sublethal Effects of Ethylmercury Chloride on Chinese Rare Minnow (Gobiocypris rarus): Accumulation, Elimination, and Histological Changes.

Ethylmercury (EtHg) has been widely observed in the environment due to anthropogenic contamination and/or environmental ethylation of inorganic mercury. Herein, the acute and sublethal effect of EtHg chloride on Chinese rare minnow (Gobiocypris rarus) as a fish model was studied. EtHg chloride showed an obvious toxicity to 4-month-old Chinese rare minnow (LC50 24.8 µg L-1 (as Hg) at 24 h). Histological analysis revealed that acute EtHg exposure can induce necrosis, telangiectasis and exfoliation of epithelial cells in the gill, as well as edema, vacuoles, and pyknotic nuclei in hepatocytes. Sublethal dose exposure revealed a very high accumulation of EtHg in fish, which is subsequently metabolized to inorganic mercury and eliminated after depuration. A new mercury species, possibly diethylmercury, was also observed as the metabolite of EtHg in rare minnow. The present study provides useful information for assessing the risks of EtHg and understanding its bioaccumulation in aquatic organisms.