Integrative analysis of bulk and single-cell RNA sequencing reveals the gene expression profile and the critical signaling pathways of type II CPAM.

BACKGROUD: Type II congenital pulmonary airway malformation (CPAM) is a rare pulmonary microcystic developmental malformation. Surgical excision is the primary treatment for CPAM, although maternal steroids and betamethasone have proven effective in reducing microcystic CPAM. Disturbed intercellular communication may contribute to the development of CPAM. This study aims to investigate the expression profile and analyze intercellular communication networks to identify genes potentially associated with type II CPAM pathogenesis and therapeutic targets. METHODS: RNA sequencing (RNA-seq) was performed on samples extracted from both the cystic area and the adjacent normal tissue post-surgery in CPAM patients. Iterative weighted gene correlation network analysis (iWGCNA) was used to identify genes specifically expressed in type II CPAM. Single-cell RNA-seq (scRNA-seq) was integrated to unveil the heterogeneity in cell populations and analyze the communication and interaction within epithelial cell sub-populations. RESULTS: A total of 2,618 differentially expressed genes were identified, primarily enriched in cilium-related biological process and inflammatory response process. Key genes such as EDN1, GPR17, FPR2, and CHRM1, involved in the G protein-coupled receptor (GPCR) signaling pathway and playing roles in cell differentiation, apoptosis, calcium homeostasis, and the immune response, were highlighted based on the protein-protein interaction network. Type II CPAM-associated modules, including ciliary function-related genes, were identified using iWGCNA. By integrating scRNA-seq data, AGR3 (related to calcium homeostasis) and SLC11A1 (immune related) were identified as the only two differently expressed genes in epithelial cells of CPAM. Cell communication analysis revealed that alveolar type 1 (AT1) and alveolar type 2 (AT2) cells were the predominant communication cells for outgoing and incoming signals in epithelial cells. The ligands and receptors between epithelial cell subtypes included COLLAGEN genes enriched in PI3K-AKT singaling and involved in epithelial to mesenchymal transition. CONCLUSIONS: In summary, by integrating bulk RNA-seq data of type II CPAM with scRNA-seq data, the gene expression profile and critical signaling pathways such as GPCR signaling and PI3K-AKT signaling pathways were revealed. Abnormally expressed genes in these pathways may disrupt epithelial-mesenchymal transition and contribute to the development of CPAM. Given the effectiveness of prenatal treatments of microcystic CPAM using maternal steroids and maternal betamethasone administration, targeting the genes and signaling pathways involved in the development of CPAM presents a promising therapeutic strategy.

Screening for early rheumatoid arthritis using high-frequency ultrasound, serum RANKL, and OPG detection.

OBJECTIVE: To conduct a comparative study of high-frequency ultrasound and magnetic resonance imaging (MRI) combined with serum RANKL and OPG detection, and assess the efficacy of high-frequency ultrasound with RANKL and OPG detection in screening early rheumatoid arthritis (RA). METHOD: High-frequency ultrasound and MRI were performed on both carpal joints of 60 patients with early RA, and the frequencies of synovitis, joint effusion, tenosynovitis, and bone erosion detected by high-frequency ultrasound and MRI were observed. The serum levels of receptor activator for nuclear factor-κB ligand (RANKL) and osteoclastogenesis inhibitory factor (OPG) were also detected. The serum levels of RANKL and OPG were also detected in 80 normal healthy examinees. The data were recorded and statistically analyzed. RESULTS: The detection rates of carpal synovitis, joint effusion, tenosynovitis, and bone erosion in RA patients by high-frequency ultrasound were 81.66%, 69.16%, 63.33%, and 1.66%, respectively, while the detection rates by MRI were 80.00%, 71.66%, 65.00%, and 15.00%, respectively. There was no significant difference between high-frequency ultrasound and MRI in the detection rates of carpal synovitis, joint effusion, and tenosynovitis in RA patients (P > 0.05), while the detection rate of bone erosion by high-frequency ultrasound was significantly lower than that by MRI. The serum levels of RANKL and OPG in RA patients were 231.47 and 68.71, respectively, while the serum levels of RANKL and OPG in normal healthy examinees were 123.51 and 385.05, respectively. The serum RANKL levels of RA patients were significantly higher than those of healthy examinees, while the serum OPG levels of RA patients were significantly lower than those of healthy examinees, which were statistically significant (P < 0.01). The AUC values of the ROC curves obtained by high-frequency ultrasound and MRI combined with serum RANKL and OPG detection in Synovitis modeling were 0.955 and 0.954, respectively. The AUC values of the ROC curves obtained from the joint fusion modeling using high-frequency ultrasound and MRI combined with serum RANKL and OPG detection were 0.949 and 0.950, respectively. The AUC values of the ROC curves obtained from modeling Tenosynovitis using high-frequency ultrasound and MRI combined with serum RANKL and OPG detection were 0.941 and 0.949, respectively. The AUC values of ROC curves obtained by combining high-frequency ultrasound and MRI with serum RANKL and OPG detection in Bone erosion modeling were 0.908 and 0.923, respectively. CONCLUSION: High-frequency ultrasound combined with serum RANKL and OPG detection has comparable effects to MRI on screening early RA, providing a safe, simple, and cost-effective screening method for the early detection of RA patients. Key Points • High-frequency ultrasound and MRI can effectively detect early lesions of the wrist joints in RA patients. • Ultrasound diagnosis has the advantages of being quick, inexpensive, and repeatable, making it the preferred choice of imaging examination for RA patients at an early stage.

Low H3K27me3 deposition at CYP82E4 determines the nicotinic conversion rate in Nicotiana tabacum.

Nicotine conversion is the process by which nornicotine is synthesized from nicotine. The capacity of a plant to carry out this process is represented by the nicotine conversion rate (NCR), which is defined as the percentage of nornicotine content out of the total nicotine + nornicotine content. Nicotine conversion in tobacco is mediated by CYP82E4. Although there are cultivar-specific differences in NCR, these do not correspond to differences in the CYP82E4 promoter or gene body sequences, and little is known about the underlying regulatory mechanism. Here, we found that histone H3 Lysine 27 trimethylation (H3K27me3) was involved in CYP82E4 expression, functioning as a transcriptional repressor. Compared to a high-NCR near-isogenic line, a low-NCR cultivar showed increased levels of the repressive histone modification markers H3K27me3 and H3K9me3 at CYP82E4. Comparison of histone markers between several cultivars with varying NCRs showed that H3K27me3 and H3K9me3 levels were significantly associated with cultivar-specific differences in NCR. Treatment with the H3K27me3 demethylase inhibitor GSK-J4 increased total H3K27me3 levels and enriched H3K27me3 at the CYP82E4 locus; the increased levels of H3K27me3 further inhibited CYP82E4 expression. Knocking out E(z), an indispensable gene for H3K27me3 formation, decreased H3K27me3 levels at CYP82E4, leading to a more than three-fold increase in CYP82E4 expression. Changes in CYP82E4 expression during leaf senescence and chilling stress were also strongly correlated with H3K27me3 levels. These findings reveal a strong correlation between CYP82E4 expression and histone modifications, and demonstrate an instance of histone-mediated alkaloid regulation for the first time.

Long non-coding RNA FENDRR suppresses cancer-associated fibroblasts and serves as a prognostic indicator in colorectal cancer.

Genetically abnormal fibroblasts are notably more prevalent in colorectal cancer (CRC) than in adjacent normal tissue, emphasizing their significance in driving the heterogeneity of the tumor microenvironment. Functioning as a significant regulatory gene in the context of fibrosis, FOXF1 adjacent non-coding developmental regulatory RNA (FENDRR) has exhibited abnormal expression in colorectal cancer and interstitial localization in our experiments. However, current research on the role of FENDRR in cancer has focused solely on its impact on cancer cells. Its crucial role in the tumor stroma is yet to be explored. The goal of this study was to understand the relationship between atypical FENDRR expression, its distinct localization, and genetically abnormal fibroblasts in CRC. We aimed to establish the function of FENDRR within the stromal compartment of patients through bioinformatics. Our study confirmed that FENDRR suppresses cancer-associated fibroblasts by inhibiting their activation and collagen generation in CRC. Furthermore, our findings suggest that low FENDRR expression indicates a poor prognosis. Therefore, we propose that FENDRR is a promising therapeutic target for future studies in CRC.

Integrated bulk and single-cell RNA-sequencing reveals SPOCK2 as a novel biomarker gene in the development of congenital pulmonary airway malformation.

BACKGROUND: Congenital pulmonary airway malformation (CPAM) is the most frequent pulmonary developmental malformation and the pathophysiology remains poorly understood. This study aimed to identify the characteristic gene expression patterns and the marker genes essential to CPAM. METHODS: Tissues from the cystic area displaying CPAM and the area of normal appearance were obtained during surgery. Bulk RNA sequencing (RNA-seq) and single-cell RNA sequencing (scRNA-seq) were performed for integrating analysis. Iterative weighted gene correlation network analysis (iWGCNA) was used to identify specifically expressed genes to CPAM. RESULTS: In total, 2074 genes were significantly differentially expressed between the CPAM and control areas. Of these differentially expressed genes (DEGs), 1675 genes were up-regulated and 399 genes were down-regulated. Gene ontology analysis revealed these DEGs were specifically enriched in ciliated epithelium and involved in immune response. We also identified several CPAM-related modules by iWGCNA, among them, P15_I4_M3 module was the most influential module for distinguishing CPAMs from controls. By combining the analysis of the expression dataset from RNA-seq and scRNA-seq, SPOCK2, STX11, and ZNF331 were highlighted in CPAM. CONCLUSIONS: Through our analysis of expression datasets from both scRNA-seq and bulk RNA-seq of tissues obtained from patients with CPAM, we identified the characteristic gene expression patterns associated with the condition. Our findings suggest that SPOCK2 could be a potential biomarker gene for the diagnosis and therapeutic target in the development of CPAM, whereas STX11 and ZNF331 might serve as prognostic markers for this condition. Further investigations with larger samples and function studies are necessary to confirm the involvement of these genes in CPAM.

Cyclic Glycine-Proline (cGP) Normalises Insulin-Like Growth Factor-1 (IGF-1) Function: Clinical Significance in the Ageing Brain and in Age-Related Neurological Conditions.

Insulin-like growth factor-1 (IGF-1) function declines with age and is associated with brain ageing and the progression of age-related neurological conditions. The reversible binding of IGF-1 to IGF binding protein (IGFBP)-3 regulates the amount of bioavailable, functional IGF-1 in circulation. Cyclic glycine-proline (cGP), a metabolite from the binding site of IGF-1, retains its affinity for IGFBP-3 and competes against IGF-1 for IGFBP-3 binding. Thus, cGP and IGFBP-3 collectively regulate the bioavailability of IGF-1. The molar ratio of cGP/IGF-1 represents the amount of bioavailable and functional IGF-1 in circulation. The cGP/IGF-1 molar ratio is low in patients with age-related conditions, including hypertension, stroke, and neurological disorders with cognitive impairment. Stroke patients with a higher cGP/IGF-1 molar ratio have more favourable clinical outcomes. The elderly with more cGP have better memory retention. An increase in the cGP/IGF-1 molar ratio with age is associated with normal cognition, whereas a decrease in this ratio with age is associated with dementia in Parkinson disease. In addition, cGP administration reduces systolic blood pressure, improves memory, and aids in stroke recovery. These clinical and experimental observations demonstrate the role of cGP in regulating IGF-1 function and its potential clinical applications in age-related brain diseases as a plasma biomarker for-and an intervention to improve-IGF-1 function.

The early warning research on nursing care of stroke patients with intelligent wearable devices under COVID-19.

Stroke patients under the background of the new crown epidemic need to be home-based care. However, traditional nursing methods cannot take care of the patients' lives in all aspects. Based on this, based on machine learning algorithms, our work combines regression models and SVM to build a smart wearable device system and builds a system prediction module to predict patient care needs. The node is used to collect human body motion and physiological parameter information and transmit data wirelessly. The software is used to quickly process and analyze the various motion and physiological parameters of the patient and save the analysis and processing structure in the database. By comparing the results of nursing intervention experiments, we can see that the smart wearable device designed in this paper has a certain effect in stroke care.

Correction to: The early warning research on nursing care of stroke patients with intelligent wearable devices under COVID-19.

[This corrects the article DOI: 10.1007/s00779-021-01520-9.].

In Situ Metabolomics of Cortisol-Producing Adenomas.

BACKGROUND: Recent advances in omics techniques have allowed detailed genetic characterization of cortisol-producing adrenal adenoma (CPA). In contrast, the pathophysiology of CPAs has not been elucidated in detail on the level of tumor metabolic alterations. METHODS: The current study conducted a comprehensive mass spectrometry imaging (MSI) map of CPAs in relation to clinical phenotypes and immunohistochemical profiles of steroidogenic enzymes. The study cohort comprised 46 patients with adrenal tumors including CPAs (n 35) and nonfunctional adenomas (n 11). RESULTS: Severity of cortisol hypersecretion was significantly correlated with 29 metabolites (adjusted P 0.05). Adrenal androgens derived from the classic androgen pathway were inversely correlated with both cortisol secretion (rs 0.41, adjusted P 0.035) and CYP11B1 expression (rs 0.77, adjusted P 2.00E-08). The extent of cortisol excess and tumor CYP11B1 expression further correlated with serotonin (rs 0.48 and 0.62, adjusted P 0.008 and 2.41E-05). Tumor size was found to be correlated with abundance of 13 fatty acids (adjusted P 0.05) and negatively associated with 9 polyunsaturated fatty acids including phosphatidic acid 38:8 (rs 0.56, adjusted P 0.009). CONCLUSIONS: MSI reveals novel metabolic links between endocrine function and tumorigenesis, which will further support the understanding of CPA pathophysiology.

VOC characteristics and their source apportionment in a coastal industrial area in the Yangtze River Delta, China.

Volatile organic compounds (VOCs) are important precursors of secondary organic compounds and ozone, which raise major environmental concerns. To investigate the VOC emission characteristics, measurements of VOCs based on proton transfer reaction-mass spectrometry during 2017 were conducted in a coastal industrial area in Ningbo, Zhejiang Province, China. Based on seasonal variation in species concentration, the positive matrix factorization (PMF) receptor model was applied to apportion the sources of VOCs in each season. The PMF results revealed that unknown acetonitrile source, paint solvent, electronics industry, biomass burning, secondary formation and biogenic emission were mainly attributed to VOC pollution. Biomass burning and secondary formation were the major sources of VOCs and contributed more than 70% of VOC emissions in spring and autumn. Industry-related sources contributed 8.65%-31.2% of the VOCs throughout the year. The unknown acetonitrile source occurred in winter and spring, and contributed 7.6%-43.73% of the VOC emissions in the two seasons. Conditional probability function (CPF) analysis illustrated that the industry sources came from local emission, while biomass burning and biogenic emission mainly came from the northwest direction. The potential source contribution function (PSCF) model showed that secondary formation-related source was mainly from Jiangsu Province, northeastern China and the surrounding ocean. The potential source areas of unknown acetonitrile source were northern Zhejiang Province, southern Jiangsu Province and the northeastern coastal marine environments.

Wideband reflective metasurface for independent control of mode and circular polarization of orbital angular momentum.

Pancharatnam-Berry (PB) phase, usually utilized for phase manipulation of circularly polarized (CP) waves, has inherent symmetrical response on left-handed polarized (LCP) and right-handed polarized (RCP) for orbital angular momentum (OAM), which severely hinders its application. By modulating both propagation and PB phase allows independent control of LCP and RCP of OAM, but increases the design difficulty. Here, we propose a phase compensation scheme to independent control the CP states of OAM only utilizing PB phase, where arbitrary topological charges and deflection directions of LCP and RCP beams can be realized. Two wideband metasurfaces are designed to independent control the mode, circular polarization and beam directions of OAM at the frequency range of 10-20 GHz. This work significantly motivates the development of polarization division multiplexing in wireless communication system.

Anti-Cancer Activity of Gedunin by Induction of Apoptosis in Human Gastric Cancer AGS Cells.

Currently, gastric cancer is considered one of the major causes of high mortality and morbidity worldwide. Recent advances in therapeutics, clinical treatment, staging procedures, and imaging techniques are high, yet the prevalence of gastric cancer has not been reduced. Usage of the synthetic drug has many side effects that can lead to other ailments. Gedunin, a phytochemical derived from Azadirachta indica (neem tree), exhibits several pharmacological activities including antitumor, anti-inflammatory, antiulcer, antipyretics, antibacterial, antifungal, anti-diabetic, and antimalarial properties. In the current investigation, the effect of gedunin on the cell viability; reactive oxygen species (ROS) generation by DCFH-DA staining; mitochondrial membrane potential (MMP) by Rh-123 staining; apoptosis by AO/EtBr staining; cell migration and wound healing ability by wound scratch assay; and Bcl-2, Bax, caspase-3, and caspase-9 by ELISA techniques were analyzed in the AGS cells. The treatment with gedunin effectively inhibited the cell viability with IC50 = 20µM, increased the ROS generation, and triggered the apoptosis in AGS cells. The gedunin-treated AGS cells also demonstrated a decreased MMP status. The increment in the ROS generation leads to oxidative stress which in turn induce the apoptosis. The activity of Bax gene was upregulated and the activity of Bcl-2 gene was down-regulated in the AGS cells after the treatment with gedunin. In the AGS cells treated with gedunin, the caspase-3 and caspase-9 activities were increased. In overall, these findings suggested that gedunin can be used as a potent chemotherapeutic agent in the future to treat gastric cancer.

A Reliable Approach for Revealing Molecular Targets in Secondary Ion Mass Spectrometry.

Nano secondary ion mass spectrometry (nanoSIMS) imaging is a rapidly growing field in biological sciences, which enables investigators to describe the chemical composition of cells and tissues with high resolution. One of the major challenges of nanoSIMS is to identify specific molecules or organelles, as these are not immediately recognizable in nanoSIMS and need to be revealed by SIMS-compatible probes. Few laboratories have generated such probes, and none are commercially available. To address this, we performed a systematic study of probes initially developed for electron microscopy. Relying on nanoscale SIMS, we found that antibodies coupled to 6 nm gold particles are surprisingly efficient in terms of labeling specificity while offering a reliable detection threshold. These tools enabled accurate visualization and sample analysis and were easily employed in correlating SIMS with other imaging approaches, such as fluorescence microscopy. We conclude that antibodies conjugated to moderately sized gold particles are promising tools for SIMS imaging.

Molecular confirmation of the hybrid origin of Sparganium longifolium (Typhaceae).

Sparganium longifolium was reported as a hybrid between S. emersum and S. gramineum based on its intermediate type or the common characteristics of its parent species. Its hybrid origin needs to be confirmed using molecular technology. We investigated the origin of S. longifolium based on 10 populations of S. emersum, S. gramineum and S. longifolium from five lakes in European Russia, using sequences of six nuclear loci and one chloroplast DNA fragment. Haplotype network, principal coordinate analysis and genetic clustering based on data of nuclear loci confirmed that S. longifolium is the hybrid between S. emersum and S. gramineum. We found that the natural hybridization between S. emersum and S. gramineum is bidirectional but asymmetrical, and the latter mainly acts as maternal species. We also found that all samples of S. longifolium were F1 generations, and thus hypothesized that S. emersum and S. gramineum could likely maintain their species boundary through the post-zygote reproductive isolation mechanism of F1 generation sterility.

NAD+ Anabolism Disturbance Causes Glomerular Mesangial Cell Injury in Diabetic Nephropathy.

The homeostasis of NAD+ anabolism is indispensable for maintaining the NAD+ pool. In mammals, the mainly synthetic pathway of NAD+ is the salvage synthesis, a reaction catalyzed by nicotinamide mononucleotide adenylyltransferase (NAMPT) and nicotinamide mononucleotide adenylyltransferase (NMNATs) successively, converting nicotinamide (NAM) to nicotinamide mononucleotide (NMN) and NMN to NAD+, respectively. However, the relationship between NAD+ anabolism disturbance and diabetic nephropathy (DN) remains elusive. Here our study found that the disruption of NAD+ anabolism homeostasis caused an elevation in both oxidative stress and fibronectin expression, along with a decrease in Sirt1 and an increase in both NF-κB P65 expression and acetylation, culminating in extracellular matrix deposition and globular fibrosis in DN. More importantly, through constitutively overexpressing NMNAT1 or NAMPT in human mesangial cells, we revealed NAD+ levels altered inversely with NMN levels in the context of DN and, further, their changes affect Sirt1/NF-κB P65, thus playing a crucial role in the pathogenesis of DN. Accordingly, FK866, a NAMPT inhibitor, and quercetin, a Sirt1 agonist, have favorable effects on the maintenance of NAD+ homeostasis and renal function in db/db mice. Collectively, our findings suggest that NMN accumulation may provide a causal link between NAD+ anabolism disturbance and diabetic nephropathy (DN) as well as a promising therapeutic target for DN treatment.

Heparanase promotes endothelial-to-mesenchymal transition in diabetic glomerular endothelial cells through mediating ERK signaling.

Glomerular endothelial cells (GEnCs) dysfunction occurs at the early stage of diabetic nephropathy (DN). One of its characteristics is endothelial-to-mesenchymal transition (EndMT). Heparanase (HPSE) is the only known mammalian endoglycosidase capable of degrading heparin sulfates and has a prominent role in DN pathogenesis. However, whether HPSE induces EndMT of GEnCs remains unknown. This study aimed to determine the effect and potential mechanism of HPSE on GEnCs phenotype under high-glucose conditions. In the early development of streptozotocin (STZ)-induced diabetic mice, HPSE overexpression was positively correlated with renal injury and the number of GEnCs undergoing EndMT, which was characterized by loss of endothelial marker CD31 and gain of mesenchymal markers including α-SMA and Snail1/2 by double immunofluorescence staining. Bioinformatics analysis revealed a positive correlation between HPSE and ERK. The counts of double positive staining of CD31 and p-ERK1/2 was significantly increased in the glomeruli of STZ-induced diabetic mice compared with sham mice. In cultured GEnCs, high glucose dramatically upregulated the expressions of HPSE and p-ERK1/2, both of which were markedly blocked by HPSE siRNA. Furthermore, recombinant mouse HPSE (rmHPSE) promoted the expressions of mesenchymal markers and p-ERK1/2 in a dosage- and time-dependent manner. U0126, a specific MEK/ERK inhibitor, significantly inhibited either high glucose or rmHPSE-induced EndMT of GEnCs. These data indicate that high glucose induces EndMT of GEnCs at least partially through upregulating HPSE and that HPSE promotes EndMT of GEnCs via activating ERK signaling. This study improves understanding the crucial role of HPSE in DN development and progression.

Influence of different phytoremediation on soil microbial diversity and community composition in saline-alkaline land.

Soil salinization is one main environmental factor restricting plant growth and agricultural productivity. However, phytoremediation is one of the important means to improve saline-alkali soil by planting halophytes or salt-tolerant plants. In order to study whether there are differences among soil microorganisms in different phytoremediation, the effects of four plants, including alfalfa (MX), oil sunflower (YK), maize (YM) and ryegrass (HMC) on soil physicochemical properties, enzyme activity and microbial community diversity and composition were investigated in this study and the relationships between microbial community structure and soil physicochemical properties, enzyme activity were analyzed. The results showed that all plants treatments significantly decreased pH, TS (total saltinity) and BD (bulk density), while increased OM (organic matter), TN (total nitrogen), AN (available nitrogen), TP (total phosphorus), AP (available phosphorus), TK (total potassium) and TPOR (total porosity), and the number of nitrite bacteria reduced by planting at the same time. Except for YM, other treatments significantly increased the number of nitrifying and denitrifying bacteria compared with CK, while only YK increased that of fungi. Additionally, all plants increased the activity of nitrite reductase and decreased that of urease. More interestingly, plants treatments shifted microbial community compositions, and only YM significantly decreased the bacterial diversity and increased the fungal diversity. Redundancy analysis suggested that TK, pH, BD, TS, AN, OM and nitrite reductase, lignin peroxidase were the key environmental factors that shaped the bacterial community structure, while that of fungi was mainly driven by OM, nitrite reductase, urease and lignin peroxidase. The results indicated that MX and YM are the best choice for remediation of saline-alkali soil. These data can provide certain theoretical basis for the further restoration of saline-alkali land.HIGHLIGHTSThe effects of different phytoremediation on microbial diversity and community structure were different.Phytoremediation can significantly decreased pH, TS and BD, while increased OM, TN, AN, TP, AP, TK and TPOR in saline-alkali soil.All plants increased the activity of nitrite reductase and decreased the activity of urease.

Chemical constituents from the stems of Acanthopanax senticosus with their cytotoxic activities.

A new coumestan named 7,5'-dihydroxy-4'-(3''-hydroxy-3''-methyl-trans-isobut-1''-enyl) coumestan (1), together with five known compounds (2-6), was isolated from the EtOAc-soluble extract of the stems of Acanthopanax senticosus. Their structures were elucidated based on extensive spectroscopic analyses. All the isolates were evaluated for in vitro cytotoxic activities against four human cancer cells including HepG2, A549, HeLa and MCF-7. Among them, the new compound 1 was found to exhibit significant cytotoxic activity on HeLa cells with IC50 value of 6.5 µM.

Native glycan fragments detected by MALDI mass spectrometry imaging are independent prognostic factors in pancreatic ductal adenocarcinoma.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest malignancies to date. The impressively developed stroma that surrounds and modulates the behavior of cancer cells is one of the main factors regulating the PDAC growth, metastasis and therapy resistance. Here, we postulate that stromal and cancer cell compartments differentiate in protein/lipid glycosylation patterns and analyze differences in glycan fragments in those compartments with clinicopathologic correlates. RESULTS: We analyzed native glycan fragments in 109 human FFPE PDAC samples using high mass resolution matrix-assisted laser desorption/ionization Fourier-transform ion cyclotron resonance mass spectrometric imaging (MALDI-FT-ICR-MSI). Our method allows detection of native glycan fragments without previous digestion with PNGase or any other biochemical reaction. With this method, 8 and 18 native glycans were identified as uniquely expressed in only stromal or only cancer cell compartment, respectively. Kaplan-Meier survival model identified glycan fragments that are expressed in cancer cell or stromal compartment and significantly associated with patient outcome. Among cancer cell region-specific glycans, 10 predicted better and 6 worse patient survival. In the stroma, 1 glycan predicted good and 4 poor patient survival. Using factor analysis as a dimension reduction method, we were able to group the identified glycans in 2 factors. Multivariate analysis revealed that these factors can be used as independent survival prognostic elements with regard to the established Union for International Cancer Control (UICC) classification both in tumor and stroma regions. CONCLUSION: Our method allows in situ detection of naturally occurring glycans in FFPE samples of human PDAC tissue and highlights the differences among glycans found in stromal and cancer cell compartment offering a basis for further exploration on the role of specific glycans in cancer-stroma communication.