Bladder cancer risk stratification with the Oncuria 10-plex bead-based urinalysis assay using three different Luminex xMAP instrumentation platforms.

BACKGROUND: No single marker of bladder cancer (BC) exists in urine samples with sufficient accuracy for disease diagnosis and treatment monitoring. The multiplex Oncuria BC assay noninvasively quantifies the concentration of 10 protein analytes in voided urine samples to quickly generate a unique molecular profile with proven BC diagnostic and treatment-tracking utility. Test adoption by diagnostic and research laboratories mandates reliably reproducible assay performance across a variety of instrumentation platforms used in different laboratories. METHODS: We compared the performance of the clinically validated Oncuria BC multiplex immunoassay when data output was generated on three different analyzer systems. Voided urine samples from 36 subjects (18 with BC and 18 Controls) were reacted with Oncuria test reagents in three 96-well microtiter plates on Day 1, and consecutively evaluated on the LED/image-based MagPix, and laser/flow-based Luminex 200 and FlexMap 3D (all xMAP instruments from Luminex Corp., Austin, TX) on Day 2. The BC assay uses magnetic bead-based fluorescence technology (xMAP, Multi-analyte profiling; Luminex) to simultaneously quantify 10 protein analytes in urine specimens [i.e., angiogenin (ANG), apolipoprotein E (ApoE), carbonic anhydrase IX (CA9), CXCL8/interleukin-8 (IL-8), matrix metalloproteinase-9 (MMP-9), matrix metalloproteinase-10 (MMP-10), serpin A1/alpha-1 anti-trypsin (A1AT), serpin E1/plasminogen activator inhibitor-1 (PAI-1), CD138/syndecan-1 (SDC1), and vascular endothelial growth factor-A (VEGF-A)]. All three analyzers quantify fluorescence signals generated by the Oncuria assay. RESULTS: All three platforms categorized all 10 analytes in identical samples at nearly identical concentrations, with variance across systems typically < 5%. While the most contemporary instrument, the FlexMap 3D, output higher raw fluorescence values than the two comparator systems, standard curve slopes and analyte concentrations determined in urine samples were concordant across all three units. Forty-four percent of BC samples registered ≥ 1 analyte above the highest standard concentration, i.e., A1AT (n = 7/18), IL-8 (n = 5), and/or ANG (n = 2), while only one control sample registered an analyte (A1AT) above the highest standard concentration. CONCLUSION: Multiplex BC assays generate detailed molecular signatures useful for identifying BC, predicting treatment responsiveness, and tracking disease progression and recurrence. The similar performance of the Oncuria assay across three different analyzer systems supports test adaptation by clinical and research laboratories using existing xMAP platforms. TRIAL REGISTRATION: This study was registered at ClinicalTrials.gov as NCT04564781, NCT03193528, NCT03193541, and NCT03193515.

Basal Cell-derived WNT7A Promotes Fibrogenesis at the Fibrotic Niche in Idiopathic Pulmonary Fibrosis.

Loss of epithelial integrity, bronchiolarization, and fibroblast activation are key characteristics of idiopathic pulmonary fibrosis (IPF). Prolonged accumulation of basal-like cells in IPF may impact the fibrotic niche to promote fibrogenesis. To investigate their role in IPF, basal cells were isolated from IPF explant and healthy donor lung tissues. Single-cell RNA sequencing was used to assess differentially expressed genes in basal cells. Basal cell and niche interaction was demonstrated with the sLP-mCherry niche labeling system. Luminex assays were used to assess cytokines secreted by basal cells. The role of basal cells in fibroblast activation was studied. Three-dimensional organoid culture assays were used to interrogate basal cell effects on AEC2 (type 2 alveolar epithelial cell) renewal capacity. Perturbation was used to investigate WNT7A function in vitro and in a repetitive bleomycin model in vivo. We found that WNT7A is highly and specifically expressed in basal-like cells. Proteins secreted by basal cells can be captured by neighboring fibroblasts and AEC2s. Basal cells or basal cell-conditioned media activate fibroblasts through WNT7A. Basal cell-derived WNT7A inhibits AEC2 progenitor cell renewal in three-dimensional organoid cultures. Neutralizing antibodies against WNT7A or a small molecule inhibitor of Frizzled signaling abolished basal cell-induced fibroblast activation and attenuated lung fibrosis in mice. In summary, basal cells and basal cell-derived WNT7A are key components of the fibrotic niche, providing a unique non-stem cell function of basal cells in IPF progression and a novel targeting strategy for IPF.

Biomarkers of Chronic Pancreatitis: A systematic literature review.

BACKGROUND: Chronic pancreatitis (CP) does not have diagnostic or prognostic biomarkers. CP is the end stage of a progressive inflammatory syndrome that is diagnosed at late stages by morphologic features. To diagnose earlier stages of the disease, a new mechanistic definition was established based on identifying underlying pathogenic processes and biomarker evidence of disease activity and stage. Although multiple risk factors are known, the corresponding biomarkers needed to make a highly accurate diagnosis of earlier disease stages have not been established. The goal of this study is to systematically analyze the literature to identify the most likely candidates for development into biomarkers of CP. METHODS: We conducted a systematic review of candidate analytes from easily accessible biological fluids and identified 67 studies that compared CP to nonpancreatic-disease controls. We then ranked candidate biomarkers for sensitivity and specificity by area under the receiver operator curves (AUROCs). RESULTS: Five biomarkers had a large effect size (an AUROC > 0.96), whereas 30 biomarkers had a moderate effect size (an AUROC between 0.96 and 0.83) for distinguishing CP cases from controls or other diseases. However, the studies reviewed had marked variability in design, enrollment criteria, and biospecimen sample handling and collection. CONCLUSIONS: Several biomarkers have the potential for evaluation in prospective cohort studies and should be correlated with risk factors, clinical features, imaging studies and outcomes. The Consortium for the Study of Chronic Pancreatitis, Diabetes and Pancreas Cancer provides recommendations for avoiding design biases and heterogeneity in sample collection and handling in future studies.

The Orai Ca2+ channel inhibitor CM4620 targets both parenchymal and immune cells to reduce inflammation in experimental acute pancreatitis.

KEY POINTS: This work confirms previous reports that CM4620, a small molecule inhibitor of Ca2+ entry via store operated Ca2+ entry (SOCE) channels formed by stromal interaction molecule 1 (STIM1)/Orai complexes, attenuates acinar cell pathology and acute pancreatitis in mouse experimental models. Here we report that intravenous administration of CM4620 reduces the severity of acute pancreatitis in the rat, a hitherto untested species. Using CM4620, we probe further the mechanisms whereby SOCE via STIM1/Orai complexes contributes to the disease in pancreatic acinar cells, supporting a role for endoplasmic reticulum stress/cell death pathways in these cells. Using CM4620, we show that SOCE via STIM1/Orai complexes promotes neutrophil oxidative burst and inflammatory gene expression during acute pancreatitis, including in immune cells which may be either circulating or invading the pancreas. Using CM4620, we show that SOCE via STIM1/Orai complexes promotes activation and fibroinflammatory gene expression within pancreatic stellate cells. ABSTRACT: Key features of acute pancreatitis include excess cellular Ca2+ entry driven by Ca2+ depletion from the endoplasmic reticulum (ER) and subsequent activation of store-operated Ca2+ entry (SOCE) channels in the plasma membrane. In several cell types, including pancreatic acinar, stellate cells (PaSCs) and immune cells, SOCE is mediated via channels composed primarily of Orai1 and stromal interaction molecule 1 (STIM1). CM4620, a selective Orai1 inhibitor, prevents Ca2+ entry in acinar cells. This study investigates the effects of CM4620 in preventing or reducing acute pancreatitis features and severity. We tested the effects of CM4620 on SOCE, trypsinogen activation, acinar cell death, activation of NFAT and NF-κB, and inflammatory responses in ex vivo and in vivo rodent models of acute pancreatitis and human pancreatic acini. We also examined whether CM4620 inhibited cytokine release in immune cells, fibro-inflammatory responses in PaSCs, and oxidative burst in neutrophils, all cell types participating in pancreatitis. CM4620 administration to rats by i.v. infusion starting 30 min after induction of pancreatitis significantly diminished pancreatitis features including pancreatic oedema, acinar cell vacuolization, intrapancreatic trypsin activity, cell death signalling and acinar cell death. CM4620 also decreased myeloperoxidase activity and inflammatory cytokine expression in pancreas and lung tissues, fMLF peptide-induced oxidative burst in human neutrophils, and cytokine production in human peripheral blood mononuclear cells (PBMCs) and rodent PaSCs, indicating that Orai1/STIM1 channels participate in the inflammatory responses of these cell types during acute pancreatitis. These findings support pathological Ca2+ entry-mediated cell death and proinflammatory signalling as central mechanisms in acute pancreatitis pathobiology.

The Combination of Alcohol and Cigarette Smoke Induces Endoplasmic Reticulum Stress and Cell Death in Pancreatic Acinar Cells.

BACKGROUND & AIMS: Smoking, an independent risk factor for pancreatitis, accelerates the development of alcoholic pancreatitis. Alcohol feeding of mice induces up-regulation of spliced X-box binding protein 1 (XBP1s), which regulates the endoplasmic reticulum (ER) unfolded protein response and promotes cell survival upon ER stress. We examined whether smoking affects the adaptive mechanisms induced by alcohol and accelerates disorders of the ER in pancreatic acinar cells. METHODS: We studied the combined effects of ethanol (EtOH) and cigarette smoke extract (CSE) on ER stress and cell death responses in mouse and human primary acini and the acinar cell line AR42J. Cells were incubated with EtOH (50 mmol/L), CSE (20-40 µg/mL), or both (CSE+EtOH), and analyzed by immunoblotting, quantitative reverse-transcription polymerase chain reaction, and cell death assays. Some cells were incubated with MKC-3946, an inhibitor of endoplasmic reticulum to nucleus signaling 1 (ERN1, also called IRE1) that blocks XBP1s formation. Male Sprague-Dawley rats were fed isocaloric amounts of an EtOH-containing (Lieber-DeCarli) or control diet for 11 weeks and exposed to cigarette smoke or room air in an exposure chamber for 2 hours each day. During the last 3 weeks, a subset of rats received intravenous injections of lipopolysaccharide (LPS, 3 mg/kg per week) to induce pancreatitis or saline (control). Pancreatic tissues were collected and analyzed by histology and immunostaining techniques. RESULTS: In AR42J and primary acini, CSE+EtOH induced cell death (necrosis and apoptosis), but neither agent alone had this effect. Cell death was associated with a significant decrease in expression of XBP1s. CSE+EtOH, but neither agent alone, slightly decreased adenosine triphosphate levels in AR42J cells, but induced oxidative stress and sustained activation (phosphorylation) of eukaryotic translation initiation factor 2 alpha kinase 3 (EIF2AK3, also called PERK) and increased protein levels of DNA damage inducible transcript 3 (DDIT3, also called CHOP). CHOP regulates transcription to promote apoptosis. Incubation of AR42J or primary mouse or human acinar cells with MKC-3946 reduced expression of XBP1s, increased levels of CHOP, and induced cell death. In rats fed an EtOH diet, exposure to cigarette smoke increased ER stress in acinar cells and sensitized the pancreas to LPS-induced pathology. CONCLUSIONS: Cigarette smoke promotes cell death and features of pancreatitis in EtOH-sensitized acinar cells by suppressing the adaptive unfolded protein response signaling pathway. It also activates ER stress pathways that promote acinar cell death.

Human Pancreatic Acinar Cells: Proteomic Characterization, Physiologic Responses, and Organellar Disorders in ex Vivo Pancreatitis.

Knowledge of the molecular mechanisms of acute pancreatitis is largely based on studies using rodents. To assess similar mechanisms in humans, we performed ex vivo pancreatitis studies in human acini isolated from cadaveric pancreata from organ donors. Because data on these human acinar preparations are sparse, we assessed their functional integrity and cellular and organellar morphology using light, fluorescence, and electron microscopy; and their proteome by liquid chromatography-tandem mass spectrometry. Acinar cell responses to the muscarinic agonist carbachol (CCh) and the bile acid taurolithocholic acid 3-sulfate were also analyzed. Proteomic analysis of acini from donors of diverse ethnicity showed similar profiles of digestive enzymes and proteins involved in translation, secretion, and endolysosomal function. Human acini preferentially expressed the muscarinic acetylcholine receptor M3 and maintained physiological responses to CCh for at least 20 hours. As in rodent acini, human acini exposed to toxic concentrations of CCh and taurolithocholic acid 3-sulfate responded with trypsinogen activation, decreased cell viability, organelle damage manifest by mitochondrial depolarization, disordered autophagy, and pathological endoplasmic reticulum stress. Human acini also secreted inflammatory mediators elevated in acute pancreatitis patients, including IL-6, tumor necrosis factor-α, IL-1ß, chemokine (C-C motif) ligands 2 and 3, macrophage inhibitory factor, and chemokines mediating neutrophil and monocyte infiltration. In conclusion, human cadaveric pancreatic acini maintain physiological functions and have similar pathological responses and organellar disorders with pancreatitis-causing treatments as observed in rodent acini.

Insulin promotes proliferation and fibrosing responses in activated pancreatic stellate cells.

Epidemiological studies support strong links between obesity, diabetes, and pancreatic disorders including pancreatitis and pancreatic adenocarcinoma (PDAC). Type 2 diabetes (T2DM) is associated with insulin resistance, hyperglycemia, and hyperinsulinemia, the latter due to increased insulin secretion by pancreatic beta-cells. We reported that high-fat diet-induced PDAC progression in mice is associated with hyperglycemia, hyperinsulinemia, and activation of pancreatic stellate cells (PaSC). We investigated here the effects of high concentrations of insulin and glucose on mouse and human PaSC growth and fibrosing responses. We found that compared with normal, pancreata from T2DM patients displayed extensive collagen deposition and activated PaSC in islet and peri-islet exocrine pancreas. Mice fed a high-fat diet for up to 12 mo similarly displayed increasing peri-islet fibrosis compared with mice fed control diet. Both quiescent and activated PaSC coexpress insulin (IR; mainly A type) and IGF (IGF-1R) receptors, and both insulin and glucose modulate receptor expression. In cultured PaSC, insulin induced rapid tyrosine autophosphorylation of IR/IGF-1R at specific kinase domain activation loop sites, activated Akt/mTOR/p70S6K signaling, and inactivated FoxO1, a transcription factor that restrains cell growth. Insulin did not promote activation of quiescent PaSC in either 5 mM or 25 mM glucose containing media. However, in activated PaSC, insulin enhanced cell proliferation and augmented production of extracellular matrix proteins, and these effects were abolished by specific inhibition of mTORC1 and mTORC2. In conclusion, our data support the concept that increased local glucose and insulin concentrations associated with obesity and T2DM promote PaSC growth and fibrosing responses.

Pancreatic adaptive responses in alcohol abuse: Role of the unfolded protein response.

The majority of those who drink excessive amounts of alcohol do not develop pancreatic disease. One overarching hypothesis is that alcohol abuse requires additional risk factors, either environmental or genetic, for disease to occur. However, another reason be a result of alcohol-induced activation of adaptive systems that protect the pancreas from the toxic effects of alcohol. We show that mechanisms within the unfolded protein response (UPR) of the endoplasmic reticulum (ER) that can lead to protection of the pancreas from pancreatic diseases with alcohol abuse. The remarkable ability of the pancreas to adapt its machinery to alcohol abuse using UPR systems and continue functioning is the likely reason that pancreatitis from alcohol abuse does not occur in the majority of heavy drinkers. These findings indicate that methods to enhance the protective responses of the UPR can provide opportunities for prevention and treatment of pancreatic diseases.

Genetic inhibition of protein kinase Cε attenuates necrosis in experimental pancreatitis.

Understanding the regulation of death pathways, necrosis and apoptosis, in pancreatitis is important for developing therapies directed to the molecular pathogenesis of the disease. Protein kinase Cε (PKCε) has been previously shown to regulate inflammatory responses and zymogen activation in pancreatitis. Furthermore, we demonstrated that ethanol specifically activated PKCε in pancreatic acinar cells and that PKCε mediated the sensitizing effects of ethanol on inflammatory response in pancreatitis. Here we investigated the role of PKCε in the regulation of death pathways in pancreatitis. We found that genetic deletion of PKCε resulted in decreased necrosis and severity in the in vivo cerulein-induced pancreatitis and that inhibition of PKCε protected the acinar cells from CCK-8 hyperstimulation-induced necrosis and ATP reduction. These findings were associated with upregulation of mitochondrial Bak and Bcl-2/Bcl-xL, proapoptotic and prosurvival members in the Bcl-2 family, respectively, as well as increased mitochondrial cytochrome c release, caspase activation, and apoptosis in pancreatitis in PKCε knockout mice. We further confirmed that cerulein pancreatitis induced a dramatic mitochondrial translocation of PKCε, suggesting that PKCε regulated necrosis in pancreatitis via mechanisms involving mitochondria. Finally, we showed that PKCε deletion downregulated inhibitors of apoptosis proteins, c-IAP2, survivin, and c-FLIPs while promoting cleavage/inactivation of receptor-interacting protein kinase (RIP). Taken together, our findings provide evidence that PKCε activation during pancreatitis promotes necrosis through mechanisms involving mitochondrial proapoptotic and prosurvival Bcl-2 family proteins and upregulation of nonmitochondrial pathways that inhibit caspase activation and RIP cleavage/inactivation. Thus PKCε is a potential target for prevention and/or treatment of acute pancreatitis.

Effects of oxidative alcohol metabolism on the mitochondrial permeability transition pore and necrosis in a mouse model of alcoholic pancreatitis.

BACKGROUND & AIMS: Opening of the mitochondrial permeability transition pore (MPTP) causes loss of the mitochondrial membrane potential (ΔΨm) and, ultimately, adenosine triphosphate depletion and necrosis. Cells deficient in cyclophilin D (CypD), a component of the MPTP, are resistant to MPTP opening, loss of ΔΨm, and necrosis. Alcohol abuse is a major risk factor for pancreatitis and is believed to sensitize the pancreas to stressors, by poorly understood mechanisms. We investigated the effects of ethanol on the pancreatic MPTP, the mechanisms of these effects, and their role in pancreatitis. METHODS: We measured ΔΨm in mouse pancreatic acinar cells incubated with ethanol alone and in combination with physiologic and pathologic concentrations of cholecystokinin-8 (CCK). To examine the role of MPTP, we used ex vivo and in vivo models of pancreatitis, induced in wild-type and CypD(-/-) mice by a combination of ethanol and CCK. RESULTS: Ethanol reduced basal ΔΨm and converted a transient depolarization, induced by physiologic concentrations of CCK, into a sustained decrease in ΔΨm, resulting in reduced cellular adenosine triphosphate and increased necrosis. The effects of ethanol and CCK were mediated by MPTP because they were not observed in CypD(-/-) acinar cells. Ethanol and CCK activated MPTP through different mechanisms-ethanol by reducing the ratio of oxidized nicotinamide adenine dinucleotide to reduced nicotinamide adenine dinucleotide, as a result of oxidative metabolism, and CCK by increasing cytosolic Ca(2+). CypD(-/-) mice developed a less-severe form of pancreatitis after administration of ethanol and CCK. CONCLUSIONS: Oxidative metabolism of ethanol sensitizes pancreatic mitochondria to activate MPTP, leading to mitochondrial failure; this makes the pancreas susceptible to necrotizing pancreatitis.

Upregulated Matrisomal Proteins and Extracellular Matrix Mechanosignaling Underlie Obesity-Associated Promotion of Pancreatic Ductal Adenocarcinoma.

Diet-induced obesity (DIO) promotes pancreatic ductal adenocarcinoma (PDAC) in mice expressing KRasG12D in the pancreas (KC mice), but the precise mechanisms remain unclear. Here, we performed multiplex quantitative proteomic and phosphoproteomic analysis by liquid chromatography-tandem mass spectrometry and further bioinformatic and spatial analysis of pancreas tissues from control-fed versus DIO KC mice after 3, 6, and 9 months. Normal pancreatic parenchyma and associated proteins were steadily eliminated and the novel proteins, phosphoproteins, and signaling pathways associated with PDAC tumorigenesis increased until 6 months, when most males exhibited cancer, but females did not. Differentially expressed proteins and phosphoproteins induced by DIO revealed the crucial functional role of matrisomal proteins, which implies the roles of upstream regulation by TGFß, extracellular matrix-receptor signaling to downstream PI3K-Akt-mTOR-, MAPK-, and Yap/Taz activation, and crucial effects in the tumor microenvironment such as metabolic alterations and signaling crosstalk between immune cells, cancer-associated fibroblasts (CAFs), and tumor cells. Staining tissues from KC mice localized the expression of several prognostic PDAC biomarkers and elucidated tumorigenic features, such as robust macrophage infiltration, acinar-ductal metaplasia, mucinous PanIN, distinct nonmucinous atypical flat lesions (AFLs) surrounded by smooth muscle actin-positive CAFs, invasive tumors with epithelial-mesenchymal transition arising close to AFLs, and expanding deserted areas by 9 months. We next used Nanostring GeoMX to characterize the early spatial distribution of specific immune cell subtypes in distinct normal, stromal, and PanIN areas. Taken together, these data richly contextualize DIO promotion of Kras-driven PDAC tumorigenesis and provide many novel insights into the signaling pathways and processes involved.

Bladder cancer risk stratification with the Oncuria 10-plex bead-based urinalysis assay using three different Luminex xMAP instrumentation platforms.

Background: No single marker of bladder cancer (BC) exists in urine samples with sufficient accuracy for disease diagnosis and treatment monitoring. The multiplex Oncuria BC assay noninvasively quantifies the concentration of 10 protein analytes in voided urine samples to quickly generate a unique molecular profile with proven BC diagnostic and treatment-tracking utility. Test adoption by diagnostic and research laboratories mandates reliably reproducible assay performance across a variety of instrumentation platforms used in different laboratories. Methods: We compared the performance of the clinically validated Oncuria BC multiplex immunoassay when data output was generated on three different analyzer systems. Voided urine samples from 36 subjects (18 with BC and 18 Controls) were reacted with Oncuria test reagents in three 96-well microtiter plates on Day 1, and consecutively evaluated on the LED/image-based MagPix, and laser/flow based Luminex 200 and FlexMap 3D (all xMAP instruments from Luminex Corp., Austin, TX) on Day 2. The BC assay uses magnetic bead-based fluorescence technology (xMAP, Multi-analyte profiling; Luminex) to simultaneously quantify 10 protein analytes in urine specimens [i.e., angiogenin (ANG), apolipoprotein E (ApoE), carbonic anhydrase IX (CA9), CXCL8/interleukin-8 (IL-8), matrix metalloproteinase-9 (MMP-9), matrix metalloproteinase-10 (MMP-10), serpin A1/alpha-1 anti-trypsin (A1AT), serpin E1/plasminogen activator inhibitor-1 (PAI-1), CD138/syndecan-1 (SDC1), and vascular endothelial growth factor-A (VEGF-A)]. Results: All three platforms categorized all 10 analytes in identical samples at nearly identical concentrations, with variance across systems typically <5%. While the most contemporary instrument, the FlexMap 3D, output higher raw fluorescence values than the two comparator systems, standard curve slopes and analyte concentrations determined in urine samples were concordant across all three units. Forty-four percent of BC samples registered ≥1 analyte above the highest standard concentration, i.e., A1AT (n=7/18), IL-8 (n=5), and/or ANG (n=2). In Controls, A1AT was higher in one sample. Conclusion: Multiplex BC assays generate detailed molecular signatures useful for identifying BC, predicting treatment esponsiveness, and tracking disease progression and recurrence. The similar performance of the Oncuria assay across three different analyzer systems supports test adaptation by clinical and research laboratories using existing xMAP platforms. Trial Registration: This study was registered at ClinicalTrials.gov as NCT04564781, NCT03193528, NCT03193541, and NCT03193515.

Low dosage combination treatment with metformin and simvastatin inhibits obesity-promoted pancreatic cancer development in male KrasG12D mice.

Pancreatic ductal adenocarcinoma (PDAC), a highly lethal disease with limited therapeutic options, may benefit from repurposing of FDA-approved drugs in preventive or interceptive strategies in high-risk populations. Previous animal studies demonstrated that the use of metformin and statins as single agents at relatively high doses restrained PDAC development. Here, four-week-old mice expressing KrasG12D in all pancreatic lineages (KC mice) and fed an obesogenic high fat, high calorie diet that promotes early PDAC development were randomized onto low dosage metformin, simvastatin, or both drugs in combination administered orally. Dual treatment attenuated weight gain, fibro-inflammation, and development of advanced PDAC precursor lesions (pancreatic intraepithelial neoplasia [PanIN]-3) in male KC mice, without significant effect in females or when administered individually. Dual-treated KC mice had reduced proliferation of PanIN cells and decreased transcriptional activity of the Hippo effectors, YAP and TAZ, which are important regulators of PDAC development. Metformin and simvastatin also synergistically inhibited colony formation of pancreatic cancer cells in vitro. Together, our data demonstrated that a combination of low doses of metformin and simvastatin inhibits PDAC development and imply that both drugs are promising agents for being tested in clinical trials for preventing pancreatic cancer progression.

Salivary Biomarker Evaluation of Chronic Pancreatitis Patients Reveals Alterations in Human Proteins, Cytokines, Prostaglandin E2 Levels, and Bacterial Diversity.

OBJECTIVES: Chronic pancreatitis (CP) is a chronic fibroinflammatory condition of the pancreas difficult to diagnose in early stages. Novel biomarkers useful to facilitate early diagnosis or treatment responses may be found in biofluids. Although saliva can be easily and noninvasively collected from patients, useful salivary biomarkers from CP patients have not yet been identified. METHODS: Here, we analyzed the proteome by quantitative proteomics, cytokine/chemokine levels by Luminex analysis, prostaglandin E2 (PGE2) levels by a mass spectrometry-based assay, and bacterial species diversity by 16S ribosomal ribonucleic acid sequencing in saliva samples from confirmed CP patients and healthy controls. RESULTS: Our results indicate the presence of various differentially expressed proteins, cytokines/chemokines, and a loss of oral bacterial diversity in the saliva of CP patients. The PGE2 levels trend toward elevation in CP patients. Area under the receiver operating characteristic curve models for proteomic, cytokine, and PGE2 assays ranged from 0.59 to 0.90. CONCLUSIONS: Collectively, our studies identify a range of putative CP biomarkers and alterations in human saliva requiring further validation. The biomarker discovery approaches we used might lead to identification of biomarkers useful for CP diagnosis and monitoring.

The unique pancreatic stellate cell gene expression signatures are associated with the progression from acute to chronic pancreatitis.

Chronic pancreatitis (CP) is characterized by irreversible fibro-inflammatory changes induced by pancreatic stellate cell (PSC). Unresolved or recurrent injury causes dysregulation of biological process following AP, which would cause CP. Here, we systematically identify genes whose expressions are unique to PSC by comparing transcriptome profiles among total pancreas, pancreatic stellate, acinar, islet and immune cells. We then identified candidate genes and correlated them with the pancreatic disease continuum by performing intersection analysis among total PSC and activated PSC genes, and genes persistently differentially expressed during acute pancreatitis (AP) recovery. Last, we examined the association between candidate genes and AP, and substantiated their potential as biomarkers in experimental AP and recurrent AP (RAP) models. A total of 68 genes were identified as highly and uniquely expressed in PSC. The PSC signatures were highly enriched with extracellular matrix remodeling genes and were significantly enriched in AP pancreas compared to healthy control tissues. Among PSC signature genes that comprised a fibrotic phenotype, 10 were persistently differentially expressed during AP recovery. SPARC was determined as a candidate marker for the pancreatic disease continuum, which was not only persistently differentially expressed even five days after AP injury, but also highly expressed in two clinical datasets of CP. Sparc was also validated as highly elevated in RAP compared to AP mice. This work highlights the unique transcriptional profiles of PSC. These PSC signatures' expression may help to identify patients with high risk of AP progression to CP.

CID755673 enhances mitogenic signaling by phorbol esters, bombesin and EGF through a protein kinase D-independent pathway.

Recently, CID755673 was reported to act as a highly selective inhibitor of protein kinase D (PKD). In the course of experiments using CID755673, we noticed that it exerted unexpected stimulatory effects on [(3)H]thymidine incorporation and cell cycle progression in Swiss 3T3 cells stimulated by bombesin, a Gq-coupled receptor agonist, phorbol 12,13-dibutyrate (PDBu), a biologically active tumor promoting phorbol ester and epidermal growth factor (EGF). These stimulatory effects could be dissociated from the inhibitory effect of CID755673 on PKD activity, since enhancement of DNA synthesis was still evident in cells with severely down-regulated PKD1 after transfection of siRNA targeting PKD1. A major point raised by our study is that CID755673 can not be considered a specific inhibitor of PKD and it should be used with great caution in experiments attempting to elucidate the role of PKD family members in cellular regulation, particularly cell cycle progression from G(1)/G(o) to S phase.

Pathogenic Carboxyl Ester Lipase (CEL) Variants Interact with the Normal CEL Protein in Pancreatic Cells.

Mutations in the gene encoding the digestive enzyme carboxyl ester lipase (CEL) are linked to pancreatic disease. The CEL variant denoted CEL-HYB predisposes to chronic pancreatitis, whereas the CEL-MODY variant causes MODY8, an inherited disorder of endocrine and exocrine pancreatic dysfunction. Both pathogenic variants exhibit altered biochemical and cellular properties compared with the normal CEL protein (CEL-WT, wild type). We here aimed to investigate effects of CEL variants on pancreatic acinar and ductal cell lines. Following extracellular exposure, CEL-HYB, CEL-MODY, and CEL-WT were endocytosed. The two pathogenic CEL proteins significantly reduced cell viability compared with CEL-WT. We also found evidence of CEL uptake in primary human pancreatic acinar cells and in native ductal tissue. Moreover, coexpression of CEL-HYB or CEL-MODY with CEL-WT affected secretion of the latter, as CEL-WT was observed to accumulate intracellularly to a higher degree in the presence of either pathogenic variant. Notably, in coendocytosis experiments, both pathogenic variants displayed a modest effect on cell viability when CEL-WT was present, indicating that the normal protein might diminish toxic effects conferred by CEL-HYB and CEL-MODY. Taken together, our findings provide valuable insight into how the pathogenic CEL variants predispose to pancreatic disease and why these disorders develop slowly over time.

Pathological Mechanisms in Diabetes of the Exocrine Pancreas: What's Known and What's to Know.

The clinical significance of diabetes arising in the setting of pancreatic disease (also known as diabetes of the exocrine pancreas, DEP) has drawn more attention in recent years. However, significant improvements still need to be made in the recognition, diagnosis and treatment of the disorder, and in the knowledge of the pathological mechanisms. The clinical course of DEP is different from type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). DEP develops in patients with previous existing exocrine pancreatic disorders which damage both exocrine and endocrine parts of pancreas, and lead to pancreas exocrine insufficiency (PEI) and malnutrition. Therefore, damage in various exocrine and endocrine cell types participating in glucose metabolism regulation likely contribute to the development of DEP. Due to the limited amount of clinical and experimental studies, the pathological mechanism of DEP is poorly defined. In fact, it still not entirely clear whether DEP represents a distinct pathologic entity or is a form of T2DM arising when ß cell failure is accelerated by pancreatic disease. In this review, we include findings from related studies in T1DM and T2DM to highlight potential pathological mechanisms involved in initiation and progression of DEP, and to provide directions for future research studies.

Targeting the CBP/ß-Catenin Interaction to Suppress Activation of Cancer-Promoting Pancreatic Stellate Cells.

BACKGROUND: Although cyclic AMP-response element binding protein-binding protein (CBP)/ß-catenin signaling is known to promote proliferation and fibrosis in various organ systems, its role in the activation of pancreatic stellate cells (PSCs), the key effector cells of desmoplasia in pancreatic cancer and fibrosis in chronic pancreatitis, is largely unknown. METHODS: To investigate the role of the CBP/ß-catenin signaling pathway in the activation of PSCs, we have treated mouse and human PSCs with the small molecule specific CBP/ß-catenin antagonist ICG-001 and examined the effects of treatment on parameters of activation. RESULTS: We report for the first time that CBP/ß-catenin antagonism suppresses activation of PSCs as evidenced by their decreased proliferation, down-regulation of "activation" markers, e.g., α-smooth muscle actin (α-SMA/Acta2), collagen type I alpha 1 (Col1a1), Prolyl 4-hydroxylase, and Survivin, up-regulation of peroxisome proliferator activated receptor gamma (Ppar-γ) which is associated with quiescence, and reduced migration; additionally, CBP/ß-catenin antagonism also suppresses PSC-induced migration of cancer cells. CONCLUSION: CBP/ß-catenin antagonism represents a novel therapeutic strategy for suppressing PSC activation and may be effective at countering PSC promotion of pancreatic cancer.

Protein kinase D isozymes activation and localization during mitosis.

The protein kinase D (PKD) family consists of three serine/threonine protein kinases involved in the regulation of fundamental biological processes in response to their activation and intracellular redistribution. Although a substantial amount of information is available describing the mechanisms regulating the activation and intracellular distribution of the PKD isozymes during interphase, nothing is known of their activation status, localization and role during mitosis. The results presented in this study indicate that during mitosis, PKD3 and PKD are phosphorylated at Ser(731) and Ser(744) within their activation loop by a mechanism that requires protein kinase C. Mitosis-associated PKD3 Ser(731) and PKD Ser(744) phosphorylation is related to the catalytic activation of these kinases as evidenced by in vivo phosphorylation of histone deacetylase 5, a substrate of PKD and PKD3. Activation loop-phosphorylated PKD3 and PKD, as well as PKD2, associate with centrosomes, spindles and midbody suggesting that these activated kinases establish dynamic interactions with the mitotic apparatus. Thus, this study reveals a connection between the PKD isozymes and cell division, suggesting a novel role for this family of serine/threonine kinases.