Fast Track Adaptation of Oncolytic Coxsackie B3 Virus to Resistant Colorectal Cancer Cells - a Method to Personalize Virotherapy.

Background: The efficacy of oncolytic viruses (OV) in cancer treatment depends on their ability to successfully infect and destroy tumor cells. However, patients' tumors vary, and in the case of individual insensitivity to an OV, therapeutic efficacy is limited. Here, we present a protocol for rapid generation of tumor cell-specific adapted oncolytic coxsackievirus B3 (CVB3) with enhanced oncolytic potential and a satisfactory safety profile.

Sequential in vivo labeling of insulin secretory granule pools in - transgenic pigs.

β cells produce, store, and secrete insulin upon elevated blood glucose levels. Insulin secretion is a highly regulated process. The probability for insulin secretory granules to undergo fusion with the plasma membrane or being degraded is correlated with their age.

miR-375- and miR-1-Regulated Coxsackievirus B3 Has No Pancreas and Heart Toxicity But Strong Antitumor Efficiency in Colorectal Carcinomas.

Coxsackievirus B3 (CVB3) has strong oncolytic activity in colorectal carcinoma but it also infects the pancreas and the heart. To improve the safety of the virus, here we investigated whether pancreas and cardiac toxicity can be prevented by insertion of target sites (TS), which are complementary to miR-375 and miR-1 into the viral genome. Although miR-375 and miR-1 are abundantly expressed in the pancreas and in the heart, respectively, their expression levels are low in colorectal carcinomas, which allows the carcinomas to be selectively attacked.

The making of insulin in health and disease.

The discovery of insulin in 1921 has been one of greatest scientific achievements of the 20th century. Since then, the availability of insulin has shifted the focus of diabetes treatment from trying to keep patients alive to saving and improving the life of millions. Throughout this time, basic and clinical research has advanced our understanding of insulin synthesis and action, both in healthy and pathological conditions.

Systems biology of the IMIDIA biobank from organ donors and pancreatectomised patients defines a novel transcriptomic signature of islets from individuals with type 2 diabetes.

Aims/hypothesis: Pancreatic islet beta cell failure causes type 2 diabetes in humans. To identify transcriptomic changes in type 2 diabetic islets, the Innovative Medicines Initiative for Diabetes: Improving beta-cell function and identification of diagnostic biomarkers for treatment monitoring in Diabetes (IMIDIA) consortium ( www.imidia.

A 4D view on insulin secretory granule turnover in the β-cell.

Insulin secretory granule (SG) turnover consists of several highly regulated processes allowing for proper β-cell function and insulin secretion. Besides the spatial distribution of insulin SGs, their age has great impact on the likelihood of their secretion and their behaviour within the β-cell. While quantitative measurements performed decades ago demonstrated the preferential secretion of young insulin, new experimental approaches aim to investigate insulin ageing at the granular level.

Mechanisms of Beta Cell Dysfunction Associated With Viral Infection.

Type 1 diabetes (T1D) results from genetic predisposition and environmental factors leading to the autoimmune destruction of pancreatic beta cells. Recently, a rapid increase in the incidence of childhood T1D has been observed worldwide; this is too fast to be explained by genetic factors alone, pointing to the spreading of environmental factors linked to the disease. Enteroviruses (EVs) are perhaps the most investigated environmental agents in relationship to the pathogenesis of T1D.

Polymorphism rs11085226 in the gene encoding polypyrimidine tract-binding protein 1 negatively affects glucose-stimulated insulin secretion.

Objective: Polypyrimidine tract-binding protein 1 (PTBP1) promotes stability and translation of mRNAs coding for insulin secretion granule proteins and thereby plays a role in β-cells function. We studied whether common genetic variations within the PTBP1 locus influence insulin secretion, and/or proinsulin conversion.

Methods: We genotyped 1,502 healthy German subjects for four tagging single nucleotide polymorphisms (SNPs) within the PTBP1 locus (rs351974, rs11085226, rs736926, and rs123698) covering 100% of genetic variation with an r(2)≥0.

β2-Syntrophin is a Cdk5 substrate that restrains the motility of insulin secretory granules.

The molecular basis for the interaction of insulin granules with the cortical cytoskeleton of pancreatic β-cells remains unknown. We have proposed that binding of the granule protein ICA512 to the PDZ domain of β2-syntrophin anchors granules to actin filaments and that the phosphorylation/dephosphorylation of β2-syntrophin regulates this association. Here we tested this hypothesis by analyzing INS-1 cells expressing GFP-β2-syntrophin through the combined use of biochemical approaches, imaging studies by confocal and total internal reflection fluorescence microscopy as well as electron microscopy.

Rapid changes of mRNA-binding protein levels following glucose and 3-isobutyl-1-methylxanthine stimulation of insulinoma INS-1 cells.

Glucose and cAMP-inducing agents such as 3-isobutyl-1-methylxanthine (IBMX) rapidly change the expression profile of insulin-producing pancreatic beta-cells mostly through post-transcriptional mechanisms. A thorough analysis of these changes, however, has not yet been performed. By combining two-dimensional differential gel electrophoresis and mass spectrometry, we identified 165 spots, corresponding to 78 proteins, whose levels significantly change after stimulation of the beta-cell model INS-1 cells with 25 mM glucose + 1 mM IBMX for 2 h.

ICA512 signaling enhances pancreatic beta-cell proliferation by regulating cyclins D through STATs.

Changes in metabolic demands dynamically regulate the total mass of adult pancreatic beta-cells to adjust insulin secretion and preserve glucose homeostasis. Glucose itself is a major regulator of beta-cell proliferation by inducing insulin secretion and activating beta-cell insulin receptors. Here, we show that islet cell autoantigen 512 (ICA512)/IA-2, an intrinsic tyrosine phosphatase-like protein of the secretory granules, activates a complementary pathway for beta-cell proliferation.

cAMP-dependent phosphorylation of PTB1 promotes the expression of insulin secretory granule proteins in beta cells.

Glucose stimulates the exocytosis of insulin secretory granules of pancreatic beta cells. Granule stores are quickly refilled by activation of posttranscriptional mechanisms that enhance the biosynthesis of granule components. Rapid replacement of granules is important to sustain insulin secretion, since new granules appear to be preferentially released.

Effect of oxygenated perfluorocarbons on isolated rat pancreatic islets in culture.

One impediment for a wider application of islet transplantation is the limited number of donor pancreata for islet isolation. A more efficient utilization of available organs could in part alleviate this problem. Perfluorocarbons (PFCs) have a high oxygen solubility coefficient and maintain high oxygen partial pressures for extended time.

Nuclear translocation of an ICA512 cytosolic fragment couples granule exocytosis and insulin expression in {beta}-cells.

Islet cell autoantigen 512 (ICA512)/IA-2 is a receptor tyrosine phosphatase-like protein associated with the insulin secretory granules (SGs) of pancreatic beta-cells. Here, we show that exocytosis of SGs and insertion of ICA512 in the plasma membrane promotes the Ca(2+)-dependent cleavage of ICA512 cytoplasmic domain by mu-calpain. This cleavage occurs at the plasma membrane and generates an ICA512 cytosolic fragment that is targeted to the nucleus, where it binds the E3-SUMO ligase protein inhibitor of activated signal transducer and activator of transcription-y (PIASy) and up-regulates insulin expression.

Postmitotic differentiation of rat lung fibroblasts: induction by bleomycin and effect on prolyl 4-hydroxylase.

The cytostatic drug bleomycin (BLM) induces pulmonary fibrosis as its main side effect. Fibroblasts in fibrotic foci are the main cellular source for extracellular matrix accumulation that typifies fibrosis. In vitro studies demonstrated the ability of cytotoxic drugs to induce terminal differentiation of fibroblasts.

Polypyrimidine tract-binding protein promotes insulin secretory granule biogenesis.

Pancreatic beta-cells store insulin in secretory granules that undergo exocytosis upon glucose stimulation. Sustained stimulation depletes beta-cells of their granule pool, which must be quickly restored. However, the factors promoting rapid granule biogenesis are unknown.

Evidence for the involvement of TGF-beta and PDGF in the regulation of prolyl 4-hydroxylase and lysyloxidase in cultured rat lung fibroblasts.

Lung fibrosis is the end-point of numerous lung disorders induced by a pneumonia or by a variety of different noxes, one of which is the cytostatic drug bleomycin (BLM). Fibrosis is characterized by excessive extracellular matrix accumulation. Macrophage-fibroblast interactions are suggested to play an important role in the development of this disease.