Modeling of new markers for the diagnosis and prognosis of pancreatic cancer based on the transition from inflammation to cancer.

Background: Pancreatic adenocarcinoma (PAAD) is a lethal disease with a poor prognosis. Genes involved in acute pancreatitis (AP) or chronic pancreatitis (CP) might be important for PAAD development. This study sought to identify potential PAAD diagnosis markers and to establish a PAAD prognosis prediction model based on AP- and CP-related genes. Methods: The significantly differentially expressed genes in both AP or CP and PAAD were obtained by a bioinformatics analysis. A risk-score model for predicting survival was constructed based on The Cancer Genome Atlas (TCGA) data and validated using an International Cancer Genome Consortium (ICGC) cohort. Protein expression and the effects of the genes in the risk models were validated by immunohistochemistry, or Cell Counting Kit-8 (CCK-8) and transwell assays. The study sample data included six AP tissue samples and five normal pancreatic tissue samples, six CP tissue samples and six normal pancreatic tissue samples from the Gene Expression Omnibus (GEO) expression profiling microarrays GSE109227 and GSE41418 data sets, respectively, and fragments per kilobase per million mapped fragments (FPKM) data from four normal controls and 150 PAAD cases from TCGA database, and 182 cancer patient samples with complete survival prognostic data from the ICGC database. Results: In total, 508 significantly differentially expressed genes were found in both AP or CP and PAAD. Trefoil factor 2 (TFF2), tubulointerstitial nephritis antigen (TINAG), trefoil factor 1 (TFF1), aquaporin 5 (AQP5), SAM pointed domain containing ETS transcription factor (SPDEF), anterior gradient protein 2 (AGR2), apolipoprotein B messenger RNA editing enzyme catalytic subunit 1 (APOBEC1), kallikrein-related peptidase 6 (KLK6), dopa decarboxylase (DDC), mucin 13 (MUC13), claudin 18 (CLDN18), annexin A10 (ANXA10), and tetraspanin 1 (TSPAN1) were found to be present in PAAD and had the largest fold change. A risk-score model, comprising 19 genes, was constructed for prognostic prediction. A high-risk score indicated a poor prognosis. TINAG, DDC, SPDEF, and APOBEC1 proteins were increased in PAAD, while TINAG and DDC were correlated with the pathologic grade. Decreased TINAG, APOBEC1, transmembrane protein 94 (TMEM94), and kelch like family member 36 (KLHL36) expression inhibited PAAD cell proliferation, while decreased SPDEF, TMEM94, and KLHL36 expression significantly inhibited PAAD cell migration. Conclusions: The AP and CP co-related genes were significantly correlated with PAAD. TINAG, DDC, SPDEF, and APOBEC1 could serve as new PAAD predictors. The risk model developed in this study could be used to predict the prognosis of PAAD patients.

Pyrazole derivative Z10 ameliorates acute pancreatitis by inhibiting the ERK/Ddt pathway.

Acute pancreatitis (AP) can lead to death; however, there is no specific treatment for AP. Screening of drugs for AP treatment is rarely performed. Compounds were screened in a primary pancreatic acinar cell and peritoneal macrophage coculture system. Compounds were used in vitro and in vivo. Compound targets were predicted and validated. Among the 18 nitrogen-containing heterocycles, Z10 was shown to decrease the cerulein plus lipopolysaccharide (CL)-induced secretion of both acinar digestive enzymes and macrophage cytokines. Z10 was also shown to ameliorate CL-induced or sodium taurocholate-induced AP in mice. Proteomics analysis and enzyme linked immunosorbent assay (ELISA) revealed that Z10 decreased the levels of D-dopachrome tautomerase (Ddt) within macrophages and those in the extracellular milieu under CL treatment. Z10 also decreased Ddt expression in AP mice. Moreover, exogenous Ddt induced cytokine and digestive enzyme secretion, which could be inhibited by Z10. Ddt knockdown inhibited CL-induced cytokine secretion. Medium from CL-treated macrophages induced the release of amylase by acinar cells, and Ddt knockdown medium decreased amylase secretion. The target of Z10 was predicted to be ERK2. Z10 increased the thermostability of ERK1/2 but not ERK1 K72A/ERK2 K52A. The docking poses of ERK1 and ERK2 with Z10 were similar. Z10 inhibited ERK1/2 phosphorylation, and Ddt levels and cytokines were regulated by ERK1/2 during AP. Additionally, Z10 could not further inhibit cytokines under ERK1/2 knockdown with CL. Thus, this study revealed that Z10-mediated ERK1/2 inhibition decreased Ddt expression and secretion by macrophages. Ddt inhibition decreased cytokine release and digestive enzyme secretion.

Developmental potency of human ES cell-derived mesenchymal stem cells revealed in mouse embryos following blastocyst injection.

Mesenchymal stem cells (MSCs) are present in almost all the tissues in the body, critical for their homeostasis and regeneration. However, the stemness of MSCs is mainly an in vitro observation, and lacking exclusive markers for endogenous MSCs makes it difficult to study the multipotency of MSCs in vivo, especially for human MSCs. To address this hurdle, we injected GFP-tagged human embryonic stem cell (hESC)-derived MSCs (EMSCs) into mouse blastocysts. EMSCs survived well and penetrated both the inner cell mass and trophectoderm, correlating to the higher anti-apoptotic capability of EMSCs than hESCs. Injected EMSCs contributed to skeletal, dermal, and extraembryonic tissues in the resultant chimera and partially rescued skeletal defects in Sox9+/- mouse fetuses. Thus, this study provides evidence for the stemness and developmental capability of human MSCs through chimerization with the mouse blastocyst, serving as a model for studying human mesenchymal and skeletal development.

Advances in biological functions and mechanisms of histone variants in plants.

Nucleosome is the basic subunit of chromatin, consisting of approximately 147bp DNA wrapped around a histone octamer, containing two copies of H2A, H2B, H3 and H4. A linker histone H1 can bind nucleosomes through its conserved GH1 domain, which may promote chromatin folding into higher-order structures. Therefore, the complexity of histones act importantly for specifying chromatin and gene activities. Histone variants, encoded by separate genes and characterized by only a few amino acids differences, can affect nucleosome packaging and stability, and then modify the chromatin properties. Serving as carriers of pivotal genetic and epigenetic information, histone variants have profound significance in regulating plant growth and development, response to both biotic and abiotic stresses. At present, the biological functions of histone variants in plant have become a research hotspot. Here, we summarize recent researches on the biological functions, molecular chaperons and regulatory mechanisms of histone variants in plant, and propose some novel research directions for further study of plant histone variants research field. Our study will provide some enlightens for studying and understanding the epigenetic regulation and chromatin specialization mediated by histone variant in plant.

Preclinical safety evaluation and tracing of human mesenchymal stromal cell spheroids following intravenous injection into cynomolgus monkeys.

We have previously demonstrated that mesenchymal stromal/stem cells (MSCs) in spheroids (MSCsp) tolerate ambient and hypoxic conditions for a prolonged time. Local administration of MSCsp, but not dissociated MSCs (MSCdiss), promotes wound healing and relieves multiple sclerosis and osteoarthritis in mice and monkeys. These findings indicate an advantage of MSCsp over MSCdiss in sustaining cell viability and efficacy following transplantation, which, however, does not appear to apply to intravenous (i.v.) injection for the principal concern that MSCsp might cause embolism in small blood vessels of the host, leading to sudden death. Here, we addressed this concern by injecting human MSCsp (∼450 µm) or MSCdiss i.v. into cynomolgus monkeys. Surprisingly, no deaths occurred until sacrifice at day 21 or 60 post injection, and no remarkable physiological changes were found in the animals following the i.v. injection. The big diameters of large blood vessels in monkeys, compared to small animals like mice, may allow sufficient time for MSCsp to dissociate into single cells so they can pass through small vessels without causing embolism. Retention of MSCsp was lower in the lungs but higher in the blood than retention of MSCdiss at 1 h post injection and both disappeared at day 21. In vitro, MSCsp tolerated fluidic shear stress with higher survival than MSCdiss. Thus, i.v. injection of MSCsp into nonhuman primates is feasible, safe, and probably associated with better survival, less lung entrapment and higher efficacy than administration of MSCdiss.

Cold Stress Response Mechanisms in Anther Development.

Unlike animals that can escape threats, plants must endure and adapt to biotic and abiotic stresses in their surroundings. One such condition, cold stress, impairs the normal growth and development of plants, in which most phases of reproductive development are particularly susceptible to external low temperature. Exposed to uncomfortably low temperature at the reproductive stage, meiosis, tapetal programmed cell death (PCD), pollen viability, and fertilization are disrupted, resulting in plant sterility. Of them, cold-induced tapetal dysfunction is the main cause of pollen sterility by blocking nutrition supplements for microspore development and altering their timely PCD. Further evidence has indicated that the homeostatic imbalances of hormones, including abscisic acid (ABA) and gibberellic acid (GA), and sugars have occurred in the cold-treated anthers. Among them, cold stress gives rise to the accumulation of ABA and the decrease of active GA in anthers to affect tapetal development and represses the transport of sugar to microspores. Therefore, plants have evolved lots of mechanisms to alleviate the damage of external cold stress to reproductive development by mainly regulating phytohormone levels and sugar metabolism. Herein, we discuss the physiological and metabolic effects of low temperature on male reproductive development and the underlying mechanisms from the perspective of molecular biology. A deep understanding of cold stress response mechanisms in anther development will provide noteworthy references for cold-tolerant crop breeding and crop production under cold stress.

Finite Model Analysis and Practical Design Equations of Circular Concrete-Filled Steel Tube Columns Subjected to Compression-Torsion Load.

The objective of this study is to investigate the mechanical properties and the composite action of circular concrete-filled steel tube (CFST) columns subjected to compression-torsion load using finite element model analysis. Load-strain (T-γ) curves, normal stress, shear stress, and the composite action between the steel tubes and the interior concrete were analyzed based on the verified 3D finite element models. The results indicate that with the increase of axial force, the maximum shear stress at the core concrete increased significantly, and the maximum shear stress of the steel tubes gradually decreased. Meanwhile, the torsional bearing capacity of the column increased at first and then decreased. The torque share in the columns changed from the tube-sharing domain to the concrete-sharing domain, while the axial force of the steel tube remained unchanged. Practical design equations for the torsional capacity of axially loaded circular CFST columns were proposed based on the parametric analysis. The accuracy and validity of the proposed equations were verified against the collected experimental results.

Effect of De-Twinning on Tensile Strength of Nano-Twinned Cu Films.

Tensile tests were carried on the electroplated Cu films with various densities of twin grain boundary. With TEM images and a selected area diffraction pattern, nano-twinned structure can be observed and defined in the electroplated Cu films. The density of the nano-twin grain structure can be manipulated with the concentration of gelatin in the Cu-sulfate electrolyte solution. We found that the strength of the Cu films is highly related to the twin-boundary density. The Cu film with a greater twin-boundary density has a larger fracture strength than the Cu film with a lesser twin-boundary density. After tensile tests, necking phenomenon (about 20 µm) occurred in the fractured Cu films. Moreover, by focused ion beam (FIB) cross-sectional analysis, the de-twinning can be observed in the region where necking begins. Thus, we believe that the de-twinning of the nano-twinned structure initiates the plastic deformation of the nano-twinned Cu films. Furthermore, with the analysis of the TEM images on the nano-twinned structure in the necking region of the fractured Cu films, the de-twinning mechanism attributes to two processes: (1) the ledge formation by the engagement of the dislocations with the twin boundaries and (2) the collapse of the ledges with the opposite twin-boundaries. In conclusion, the plastic deformation of nano-twinned Cu films is governed by the de-twinning of the nano-twinned structure. Moreover, the fracture strength of the nano-twinned Cu films is proportional to the twin-boundaries density.

Alternative splicing in mesenchymal stem cell differentiation.

The differentiation and maturation of mesenchymal stem cells (MSCs) to mesodermal and other lineages are known to be controlled by various extrinsic and intrinsic signals. The dysregulation of the MSC differentiation balance has been linked to several pathophysiological conditions, including obesity and osteoporosis. Previous research of the molecular mechanisms governing MSC differentiation has mostly focused on transcriptional regulation. However, recent findings are revealing the underrated role of alternative splicing (AS) in MSC differentiation and functions. In this review, we discuss recent progress in elucidating the regulatory roles of AS in MSC differentiation. We catalogue and highlight the key AS events that modulate MSC differentiation to major osteocytes, chondrocytes, and adipocytes, and discuss the regulatory mechanisms by which AS is regulated.

Low Doses of Camptothecin Induced Hormetic and Neuroprotective Effects in PC12 Cells.

Hormetic response is an adaptive mechanism for a cell or organism surviving in an unfavorable environment. It has been an intriguing subject of researches covering a broad range of biological and medical disciplines, in which the underlying significance and molecular mechanisms are under intensive investigation. In the present study, we demonstrated that topoisomerase I inhibitor camptothecin (CPT), a potent anticancer agent, induced an obvious hormetic response in rat pheochromocytoma PC12 cells. Camptothecin inhibited PC12 cell growth at relative high doses as generally acknowledged while stimulated the cell growth by as much as 39% at low doses. Moreover, low doses of CPT protected the cells from hydrogen peroxide (H2O2)-induced cell death. Phosphoinositide 3-kinase (PI3K)/Akt and nuclear factor-E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathways were reported playing pivotal roles in protecting cells from oxidative stress. We observed that these 2 pathways were upregulated by low doses of CPT, as evidenced by increased levels of phosphorylated PI3K, phosphorylated Akt, phosphorylated mammalian target of rapamycin, Nrf2, and HO-1; and abolishment of the growth-promoting and neuroprotective effects of CPT by LY294002, a PI3K inhibitor. These results suggest that the hormetic and neuroprotective effects of CPT at low doses on PC12 cells were attributable, at least partially, to upregulated PI3K/Akt and Nrf2/HO-1 pathways.

Hormetic Effect of Berberine Attenuates the Anticancer Activity of Chemotherapeutic Agents.

Hormesis is a phenomenon of biphasic dose response characterized by exhibiting stimulatory or beneficial effects at low doses and inhibitory or toxic effects at high doses. Increasing numbers of chemicals of various types have been shown to induce apparent hormetic effect on cancer cells. However, the underlying significance and mechanisms remain to be elucidated. Berberine, one of the major active components of Rhizoma coptidis, has been manifested with notable anticancer activities. This study aims to investigate the hormetic effect of berberine and its influence on the anticancer activities of chemotherapeutic agents. Our results demonstrated that berberine at low dose range (1.25 ~ 5 µM) promoted cell proliferation to 112% ~170% of the untreated control in various cancer cells, while berberine at high dose rage (10 ~ 80 µM) inhibited cell proliferation. Further, we observed that co-treatment with low dose berberine could significantly attenuate the anticancer activity of chemotherapeutic agents, including fluorouracil (5-FU), camptothecin (CPT), and paclitaxel (TAX). The hormetic effect and thereby the attenuated anticancer activity of chemotherapeutic drugs by berberine may attributable to the activated protective stress response in cancer cells triggered by berberine, as evidenced by up-regulated MAPK/ERK1/2 and PI3K/AKT signaling pathways. These results provided important information to understand the potential side effects of hormesis, and suggested cautious application of natural compounds and relevant herbs in adjuvant treatment of cancer.

Pulsatilla Saponin D Inhibits Autophagic Flux and Synergistically Enhances the Anticancer Activity of Chemotherapeutic Agents Against HeLa Cells.

Pulsatilla saponin D (SB365), a saponin isolated from rhizoma of Pulsatilla chinensis (Bunge) Regel, exhibited anticancer activities in various cancer types. In the present study, we identified that SB365 was a potent inhibitor of autophagic flux in several cancer cell lines. SB365 induced a robust accumulation of autophagosomes as evidenced by monodansylaervarine (MDC) staining and increased protein levels of LC3-II. However, SB365 caused the accumulation of p62, a substrate that should be degraded through the autophagy-lysosomal pathway. These results indicated that SB365 was an inducer of autophagosome formation, but an inhibitor of autophagic flux. Interestingly, we found that SB365 synergistically enhanced the anticancer activity of chemotherapeutic agents against cervical cancer HeLa cells. Furthermore, our study demonstrated that SB365 increased the phosphorylation of ERK and inhibited the phosphorylation of mTOR and p70S6K, suggesting that their roles in the effects of SB365 on autophagy. These results suggest that SB365 could be a promising adjuvant anticancer agent.