Arabidopsis mRNA decay landscape shaped by XRN 5'-3' exoribonucleases.

5'-3' exoribonucleases (XRNs) play crucial roles in the control of RNA processing, quality, and quantity in eukaryotes. Although genome-wide profiling of RNA decay fragments is now feasible, how XRNs shape the plant mRNA degradome remains elusive. Here, we profiled and analyzed the RNA degradomes of Arabidopsis wild-type and mutant plants with defects in XRN activity. Deficiency of nuclear XRN3 or cytoplasmic XRN4 activity but not nuclear XRN2 activity greatly altered Arabidopsis mRNA decay profiles. Short excised linear introns and cleaved pre-mRNA fragments downstream of polyadenylation sites were polyadenylated and stabilized in the xrn3 mutant, demonstrating the unique function of XRN3 in the removal of cleavage remnants from pre-mRNA processing. Further analysis of stabilized XRN3 substrates confirmed that pre-mRNA 3' end cleavage frequently occurs after adenosine. The most abundant decay intermediates in wild-type plants include not only the primary substrates of XRN4 but also the products of XRN4-mediated cytoplasmic decay. An increase in decay intermediates with 5' ends upstream of a consensus motif in the xrn4 mutant suggests that there is an endonucleolytic cleavage mechanism targeting the 3' untranslated regions of many Arabidopsis mRNAs. However, analysis of decay fragments in the xrn4 mutant indicated that, except for microRNA-directed slicing, endonucleolytic cleavage events in the coding sequence rarely result in major decay intermediates. Together, these findings reveal the major substrates and products of nuclear and cytoplasmic XRNs along Arabidopsis transcripts and provide a basis for precise interpretation of RNA degradome data.

Microbiome signatures associated with clinical stages of gastric Cancer: whole metagenome shotgun sequencing study.

BACKGROUND: Gastric cancer is one of the global health concerns. A series of studies on the stomach have confirmed the role of the microbiome in shaping gastrointestinal diseases. Delineation of microbiome signatures to distinguish chronic gastritis from gastric cancer will provide a non-invasive preventative and treatment strategy. In this study, we performed whole metagenome shotgun sequencing of fecal samples to enhance the detection of rare bacterial species and increase genome sequence coverage. Additionally, we employed multiple bioinformatics approaches to investigate the potential targets of the microbiome as an indicator of differentiating gastric cancer from chronic gastritis. RESULTS: A total of 65 patients were enrolled, comprising 33 individuals with chronic gastritis and 32 with gastric cancer. Within each group, the chronic gastritis group was sub-grouped into intestinal metaplasia (n = 15) and non-intestinal metaplasia (n = 18); the gastric cancer group, early stage (stages 1 and 2, n = 13) and late stage (stages 3 and 4, n = 19) cancer. No significant differences in alpha and beta diversities were detected among the patient groups. However, in a two-group univariate comparison, higher Fusobacteria abundance was identified in phylum; Fusobacteria presented higher abundance in gastric cancer (LDA scored 4.27, q = 0.041 in LEfSe). Age and sex-adjusted MaAsLin and Random Forest variable of importance (VIMP) analysis in species provided meaningful features; Bacteria_caccae was the most contributing species toward gastric cancer and late-stage cancer (beta:2.43, se:0.891, p:0.008, VIMP score:2.543). In contrast, Bifidobacterium_longum significantly contributed to chronic gastritis (beta:-1.8, se:0.699, p:0.009, VIMP score:1.988). Age, sex, and BMI-adjusted MasAsLin on metabolic pathway analysis showed that GLCMANNANAUT-PWY degradation was higher in gastric cancer and one of the contributing species was Fusobacterium_varium. CONCLUSION: Microbiomes belonging to the pathogenic phylum Fusobacteria and species Bacteroides_caccae and Streptococcus_anginosus can be significant targets for monitoring the progression of gastric cancer. Whereas Bifidobacterium_longum and Lachnospiraceae_bacterium_5_1_63FAA might be protection biomarkers against gastric cancer.

Onyx™ Cast Fragmentation After Embolization of Endoleaks.

PURPOSE: Endoleaks are common following endovascular aneurysm repair (EVAR), and the liquid embolic material Onyx has been widely used in their treatment. We report our experience of long-term morphological changes of Onyx casts on surveillance imaging. MATERIALS AND METHODS: We identified 10 patients over 10 years who underwent Onyx embolization in our institution. Morphological changes of Onyx casts were assessed on surveillance radiographs and computed tomography (CT) scans. Relevant outcome data and sequelae were obtained via electronic patient records. RESULTS: Twelve procedures were performed on 10 cases, 9 for type 2, and 1 for a type 1a endoleak. Five cases showed evidence of Onyx fragmentation on follow-up imaging ranging from a single fracture to gross fragmentation with migration of fragments. Of these 5, 3 had achieved primary success but 2 went on to develop recurrence of endoleak. Onyx volume ranged from 4 to 46.5 ml (median 10.5 ml) per patient with larger volumes demonstrating the most marked fragmentation on follow-up. Follow-up ranged from 9 months to 8 years (median 2.25 years). CONCLUSION: To our knowledge, this is the first report of Onyx fragmentation after endoleak embolization. If long-term morphological stability of the Onyx cast is necessary to maintain aneurysm seal, then Onyx may not offer a permanent solution to some patients with post-EVAR endoleaks. Our study cannot ascertain whether the observed changes were the cause or the effect of ongoing aneurysm growth, persistent endoleak, and/or other forces acting on the solidified polymer, but it raises important questions on the use of Onyx in this setting.

Histone Deacetylase Inhibitors Downregulate Calcium Pyrophosphate Crystal Formation in Human Articular Chondrocytes.

Calcium pyrophosphate (CPP) deposition disease (CPPD) is a form of CPP crystal-induced arthritis. A high concentration of extracellular pyrophosphate (ePPi) in synovial fluid is positively correlated with the formation of CPP crystals, and ePPi can be upregulated by ankylosis human (ANKH) and ectonucleotide pyrophosphatase 1 (ENPP1) and downregulated by tissue non-specific alkaline phosphatase (TNAP). However, there is currently no drug that eliminates CPP crystals. We explored the effects of the histone deacetylase (HDAC) inhibitors (HDACis) trichostatin A (TSA) and vorinostat (SAHA) on CPP formation. Transforming growth factor (TGF)-ß1-treated human primary cultured articular chondrocytes (HC-a cells) were used to increase ePPi and CPP formation, which were determined by pyrophosphate assay and CPP crystal staining assay, respectively. Artificial substrates thymidine 5'-monophosphate p-nitrophenyl ester (p-NpTMP) and p-nitrophenyl phosphate (p-NPP) were used to estimate ENPP1 and TNAP activities, respectively. The HDACis TSA and SAHA significantly reduced mRNA and protein expressions of ANKH and ENPP1 but increased TNAP expression in a dose-dependent manner in HC-a cells. Further results demonstrated that TSA and SAHA decreased ENPP1 activity, increased TNAP activity, and limited levels of ePPi and CPP. As expected, both TSA and SAHA significantly increased the acetylation of histones 3 and 4 but failed to block Smad-2 phosphorylation induced by TGF-ß1. These results suggest that HDACis prevented the formation of CPP by regulating ANKH, ENPP1, and TNAP expressions and can possibly be developed as a potential drug to treat or prevent CPPD.

A multi-mode Wnt- and stemness-regulatory module dictated by FOXM1 and ASPM isoform I in gastric cancer.

BACKGROUND: Gastric cancer (GC) is the third leading cause of cancer mortality globally and a molecularly heterogeneous disease. Identifying the driver pathways in GC progression is crucial to improving the clinical outcome. Recent studies identified ASPM (abnormal spindle-like microcephaly-associated) and FOXM1 (Forkhead box protein M1) as novel Wnt and cancer stem cell (CSC) regulators; their pathogenetic roles and potential crosstalks in GC remain unclarified. METHODS: The expression patterns of ASPM isoforms and FOXM1 were profiled in normal gastric epithelial and GC tissues. The functional roles of ASPM and FOXM1 in Wnt activity, cancer stemness and GC progression, and the underlying signaling processes were investigated. RESULTS: Approximately one third of GC cells upregulate the expression of ASPM isoform I (ASPMiI) in their cytoplasm; the tumors with a high ASPMiI positive score (≥ 10%) are associated with a poor prognosis of the patients. Mechanistically, the molecular interplay among FOXM1, ASPMiI and DVL3 was found to converge on ß-catenin to control the Wnt activity and the stemness property of GC cells. This multi-mode Wnt-regulatory module serves to reinforce Wnt signals in CSCs by transcriptional regulation (FOXM1-ASPM), protein-protein interactions (ASPMiI-DVL3-ß-catenin), and nuclear translocation (FOXM1-ß-catenin). CONCLUSIONS: This study illuminates a novel Wnt- and stemness-regulatory mechanism in GC cells and identifies a novel subset of FOXM1highASPMiIhigh GC with potential to guide Wnt- and stemness-related diagnostics and therapies.

The differential distributions of ASPM isoforms and their roles in Wnt signaling, cell cycle progression, and pancreatic cancer prognosis.

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive and treatment-resistant malignancy. The lack of pathway-informed biomarkers hampers the development of rational diagnostics or therapies. Recently, the protein abnormal spindle-like microcephaly-associated (ASPM) was identified as a novel Wnt and stemness regulator in PDAC, while the pathogenic roles of its protein isoforms remain unclarified. We developed novel isoform-specific antibodies and genetic knockdown (KD) of putative ASPM isoforms, whereby we uncovered that the levels of ASPM isoform 1 (iI) and ASPM-iII are variably upregulated in PDAC cells. ASPM isoforms show remarkably different subcellular locations; specifically, ASPM-iI is exclusively localized to the cortical cytoplasm of PDAC cells, while ASPM-iII is predominantly expressed in cell nuclei. Mechanistically, ASPM-iI co-localizes with disheveled-2 and active ß-catenin as well as the stemness marker aldehyde dehydrogenase-1 (ALDH-1), and its expression is indispensable for the Wnt activity, stemness, and the tumorigenicity of PDAC cells. By contrast, ASPM-iII selectively regulates the expression level of cyclin E and cell cycle progression in PDAC cells. The expression of ASPM-iI and ASPM-iII displays considerable intratumoral heterogeneity in PDAC tissues and only that of ASPM-iI was prognostically significant; it outperformed ALDH-1 staining and clinico-pathological variables in a multivariant analysis. Collectively, the distinct expression patterns and biological functions of ASPM isoforms may illuminate novel molecular mechanisms and prognosticators in PDAC and may pave the way for the development of therapies targeting this novel oncoprotein. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Sources of Error in Interventional Radiology: How, Why, and When

This article aims to provide an overview of the sources for error in interventional radiology (IR). Being both a procedure and an imaging-based specialty, IR has unique considerations as to how error can occur. However, compared to the surgical and medical literature, data on error in IR are lacking. The available IR literature is reviewed but supplemented with lessons from other specialties and the World Health Organization. Individual risks such as cognitive bias as well as system-level factors are also considered in order to generate a taxonomy for error in IR that includes the operator, patient, team, and environment.

Aeroallergens Induce Reactive Oxygen Species Production and DNA Damage and Dampen Antioxidant Responses in Bronchial Epithelial Cells.

Exposure to environmental allergens is a major risk factor for asthma development. Allergens possess proteolytic activity that is capable of disrupting the airway epithelium. Although there is increasing evidence pointing to asthma as an epithelial disease, the underlying mechanism that drives asthma has not been fully elucidated. In this study, we investigated the direct DNA damage potential of aeroallergens on human bronchial epithelial cells and elucidated the mechanisms mediating the damage. Human bronchial epithelial cells, BEAS-2B, directly exposed to house dust mites (HDM) resulted in enhanced DNA damage, as measured by the CometChip and the staining of DNA double-strand break marker, γH2AX. HDM stimulated cellular reactive oxygen species production, increased mitochondrial oxidative stress, and promoted nitrosative stress. Notably, expression of nuclear factor erythroid 2-related factor 2-dependent antioxidant genes was reduced immediately after HDM exposure, suggesting that HDM altered antioxidant responses. HDM exposure also reduced cell proliferation and induced cell death. Importantly, HDM-induced DNA damage can be prevented by the antioxidants glutathione and catalase, suggesting that HDM-induced reactive oxygen and nitrogen species can be neutralized by antioxidants. Mechanistic studies revealed that HDM-induced cellular injury is NADPH oxidase (NOX)-dependent, and apocynin, a NOX inhibitor, protected cells from double-strand breaks induced by HDM. Our results show that direct exposure of bronchial epithelial cells to HDM leads to the production of reactive oxygen and nitrogen species that damage DNA and induce cytotoxicity. Antioxidants and NOX inhibitors can prevent HDM-induced DNA damage, revealing a novel role for antioxidants and NOX inhibitors in mitigating allergic airway disease.

Temporal Changes in Intraluminal Thrombus Volume Within Abdominal Aortic Aneurysms: Implications for Planning Endovascular Aneurysm Sealing.

PURPOSE: To explore whether or not there are temporal changes in the abdominal aortic aneurysm (AAA) and intraluminal thrombus (ILT) volumes between planning and implantation of the endovascular aneurysm sealing (EVAS) device and how these changes influence lumen volume. METHODS: A retrospective review was conducted of 51 AAA patients (mean age 76±7.1 years; 36 men) in whom 2 serial preoperative computed tomography angiograms (CTAs) had been performed within 1 to 18 months before fenestrated endovascular repair. The 2 preoperative CTAs were analyzed to identify changes in total sac, ILT, and lumen volumes. RESULTS: Over a median 7.0 months (interquartile range 4, 10), 46 (90%) of 51 AAAs increased in volume between the 2 CTAs. ILT volume increased in 44 aneurysms. In contrast, lumen volume increased in 31 and decreased in 20 AAAs. There was a strong correlation between changes in AAA volume and ILT volume (rs=0.859, p<0.001), which remained significant after adjustment for initial volumes (rs=0.815; p<0.001). There was no correlation between the time interval separating the 2 CTAs and changes in AAA volume (rs=0.115; p=0.421), changes in ILT volume (rs=0.084; p=0.599), or changes in lumen volume (rs=0.060; p=0.676). The AAA growth rate (defined as the change in AAA size/days between CTAs) showed a weak correlation with ILT volume (rs=0.272, p=0.054), which disappeared after adjustment for initial AAA size (rs=-0.002, p=0.991). Between the 2 CTAs, 12 aneurysms crossed the new <1.4 Nellix maximum aorta/lumen diameter ratio. CONCLUSION: As AAAs grow, the increase in aortic volume is largely occupied by additional ILT formation, with minimal change in lumen volume. These changes may alter the suitability of the aneurysm for the Nellix device and could have implications for EVAS planning and device deployment.

Endovascular Repair of Type IIIb Endoleak With the Amplatzer Septal Occluder.

PURPOSE: To report the successful treatment of a type IIIb endoleak with an Amplatzer Septal Occluder. CASE REPORT: A 76-year-old man was found to have a type IIIb endoleak in the proximal body component of a fenestrated graft at 4-year surveillance imaging; the leak was associated with rapid aneurysm growth. The anatomy of the graft and position of the fabric defect precluded treatment by relining with a secondary endograft. The defect was demonstrated with catheter angiography, sized with an angioplasty balloon, and repaired using an Amplatzer Septal Occluder. Follow-up imaging at 6 months showed no endoleak and marked reduction in the aneurysm size. CONCLUSION: The Amplatzer Septal Occluder may be considered as an option for managing type IIIb endoleaks.

Vitamin E Isoform γ-Tocotrienol Downregulates House Dust Mite-Induced Asthma.

Inflammation and oxidative damage contribute to the pathogenesis of asthma. Although corticosteroid is the first-line treatment for asthma, a subset of patients is steroid resistant, and chronic steroid use causes side effects. Because vitamin E isoform γ-tocotrienol possesses both antioxidative and anti-inflammatory properties, we sought to determine protective effects of γ-tocotrienol in a house dust mite (HDM) experimental asthma model. BALB/c mice were sensitized and challenged with HDM. Bronchoalveolar lavage (BAL) fluid was assessed for total and differential cell counts, oxidative damage biomarkers, and cytokine levels. Lungs were examined for cell infiltration and mucus hypersecretion, as well as the expression of antioxidants and proinflammatory biomarkers. Sera were assayed for IgE and γ-tocotrienol levels. Airway hyperresponsiveness in response to methacholine was measured. γ-Tocotrienol displayed better free radical-neutralizing activity in vitro and inhibition of BAL fluid total, eosinophil, and neutrophil counts in HDM mouse asthma in vivo, as compared with other vitamin E isoforms, including α-tocopherol. Besides, γ-tocotrienol abated HDM-induced elevation of BAL fluid cytokine and chemokine levels, total reactive oxygen species and oxidative damage biomarker levels, and of serum IgE levels, but it promoted lung-endogenous antioxidant activities. Mechanistically, γ-tocotrienol was found to block nuclear NF-κB level and enhance nuclear Nrf2 levels in lung lysates to greater extents than did α-tocopherol and prednisolone. More importantly, γ-tocotrienol markedly suppressed methacholine-induced airway hyperresponsiveness in experimental asthma. To our knowledge, we have shown for the first time the protective actions of vitamin E isoform γ-tocotrienol in allergic asthma.

House dust mite-induced asthma causes oxidative damage and DNA double-strand breaks in the lungs.

BACKGROUND: Asthma is related to airway inflammation and oxidative stress. High levels of reactive oxygen and nitrogen species can induce cytotoxic DNA damage. Nevertheless, little is known about the possible role of allergen-induced DNA damage and DNA repair as modulators of asthma-associated pathology. OBJECTIVE: We sought to study DNA damage and DNA damage responses induced by house dust mite (HDM) in vivo and in vitro. METHODS: We measured DNA double-strand breaks (DSBs), DNA repair proteins, and apoptosis in an HDM-induced allergic asthma model and in lung samples from asthmatic patients. To study DNA repair, we treated mice with the DSB repair inhibitor NU7441. To study the direct DNA-damaging effect of HDM on human bronchial epithelial cells, we exposed BEAS-2B cells to HDM and measured DNA damage and reactive oxygen species levels. RESULTS: HDM challenge increased lung levels of oxidative damage to proteins (3-nitrotyrosine), lipids (8-isoprostane), and nucleic acid (8-oxoguanine). Immunohistochemical evidence for HDM-induced DNA DSBs was revealed by increased levels of the DSB marker γ Histone 2AX (H2AX) foci in bronchial epithelium. BEAS-2B cells exposed to HDM showed enhanced DNA damage, as measured by using the comet assay and γH2AX staining. In lung tissue from human patients with asthma, we observed increased levels of DNA repair proteins and apoptosis, as shown by caspase-3 cleavage, caspase-activated DNase levels, and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling staining. Notably, NU7441 augmented DNA damage and cytokine production in the bronchial epithelium and apoptosis in the allergic airway, implicating DSBs as an underlying driver of asthma pathophysiology. CONCLUSION: This work calls attention to reactive oxygen and nitrogen species and HDM-induced cytotoxicity and to a potential role for DNA repair as a modulator of asthma-associated pathophysiology.

Cigarette Smoke-Induced Lung Disease Predisposes to More Severe Infection with Nontypeable Haemophilus influenzae: Protective Effects of Andrographolide.

Cigarette smoke (CS) is associated with many maladies, one of which is chronic obstructive pulmonary disease (COPD). As the disease progresses, patients are more prone to develop COPD exacerbation episodes by bacterial infection, particularly to nontypeable Haemophilus influenza (NTHi) infection. The present study aimed to develop a CS-exposed mouse model that increases inflammation induced by NTHi challenge and investigate the protective effects of andrographolide, a bioactive molecule with anti-inflammatory and antioxidant properties isolated from the plant Andrographis paniculata. Female BALB/c mice exposed to 2 weeks of CS followed by a single intratracheal instillation of NTHi developed increased macrophage and neutrophil pulmonary infiltration, augmented cytokine levels, and heightened oxidative damage. Andrographolide effectively reduced lung cellular infiltrates and decreased lung levels of TNF-α, IL-1ß, CXCL1/KC, 8-OHdG, matrix metalloproteinase-8 (MMP-8), and MMP-9. The protective actions of andrographolide on CS-predisposed NTHi inflammation might be attributable to increased nuclear factor erythroid-2-related factor 2 (Nrf2) activation and decreased Kelch-like ECH-associated protein 1 (Keap1) repressor function, resulting in enhanced gene expression of antioxidant enzymes including heme oxygenase-1 (HO-1), glutathione reductase (GR), glutathione peroxidase-2 (GPx-2), glutamate-cysteine ligase modifier (GCLM), and NAD(P)H quinone oxidoreductase 1 (NQO1). Taken together, these findings strongly support a therapeutic potential for andrographolide in preventing lung inflammation caused by NTHi in cigarette smokers.

Influenza infection induces host DNA damage and dynamic DNA damage responses during tissue regeneration.

Influenza viruses account for significant morbidity worldwide. Inflammatory responses, including excessive generation of reactive oxygen and nitrogen species (RONS), mediate lung injury in severe influenza infections. However, the molecular basis of inflammation-induced lung damage is not fully understood. Here, we studied influenza H1N1 infected cells in vitro, as well as H1N1 infected mice, and we monitored molecular and cellular responses over the course of 2 weeks in vivo. We show that influenza induces DNA damage to both, when cells are directly exposed to virus in vitro (measured using the comet assay) and also when cells are exposed to virus in vivo (estimated via γH2AX foci). We show that DNA damage, as well as responses to DNA damage persist in vivo until long after virus has been cleared, at times when there are inflammation associated RONS (measured by xanthine oxidase activity and oxidative products). The frequency of lung epithelial and immune cells with increased γH2AX foci is elevated in vivo, especially for dividing cells (Ki-67-positive) exposed to oxidative stress during tissue regeneration. Additionally, we observed a significant increase in apoptotic cells as well as increased levels of DNA double strand break (DSB) repair proteins Ku70, Ku86 and Rad51 during the regenerative phase. In conclusion, results show that influenza induces DNA damage both in vitro and in vivo, and that DNA damage responses are activated, raising the possibility that DNA repair capacity may be a determining factor for tissue recovery and disease outcome.

Changes in Aortic Volumes Following Endovascular Sealing of Abdominal Aortic Aneurysms With the Nellix Endoprosthesis.

PURPOSE: To investigate the effects on aortic volumes of endovascular aneurysm sealing (EVAS) with the Nellix device. METHODS: Twenty-five consecutive patients (mean age 78±7 years; 17 men) with abdominal aortic aneurysms containing thrombus were treated with EVAS. Their pre- and post-EVAS computed tomography (CT) scans were reviewed to document volume changes in the entire aneurysmal aorta, the lumen, and the intraluminal thrombus. The changes are reported as the mean and 95% confidence interval (CI). RESULTS: Total aortic volume was greater on postoperative scans by a mean 17 mL (95% CI 10.0 to 23.5, p<0.001). The volume occupied by the endobags was greater than the preoperative lumen volume by a mean 28 mL (95% CI 24.7 to 31.7, p=0.002). Postoperatively, the aortic volume occupied by thrombus had decreased by a mean 11 mL (95% CI 4.7 to 18.2, p<0.001). There were good correlations between changes in aneurysm and thrombus volumes (r=0.864, p<0.001), between the planning CT/EVAS time interval and the change in aneurysm volume (r=0.640, p=0.001), and between the planning CT/EVAS time interval and the change in thrombus volume (r=0.567, p=0.003). CONCLUSION: There are significant changes in aortic volumes post EVAS. These changes may be a direct consequence of the technique and have implications for the planning and performance of EVAS.

A gene expression signature of epithelial tubulogenesis and a role for ASPM in pancreatic tumor progression.

BACKGROUND & AIMS: Many patients with pancreatic ductal adenocarcinoma (PDAC) develop recurrent or metastatic diseases after surgery, so it is important to identify those most likely to benefit from aggressive therapy. Disruption of tissue microarchitecture is an early step in pancreatic tumorigenesis and a parameter used in pathology grading of glandular tumors. We investigated whether changes in gene expression during pancreatic epithelial morphogenesis were associated with outcomes of patients with PDAC after surgery. METHODS: We generated architectures of human pancreatic duct epithelial cells in a 3-dimensional basement membrane matrix. We identified gene expression profiles of the cells during different stages of tubular morphogenesis (tubulogenesis) and of PANC-1 cells during spheroid formation. Differential expression of genes was confirmed by immunoblot analysis. We compared the gene expression profile associated with pancreatic epithelial tubulogenesis with that of PDAC samples from 27 patients, as well as with their outcomes after surgery. RESULTS: We identified a gene expression profile associated with tubulogenesis that resembled the profile of human pancreatic tissue with differentiated morphology and exocrine function. Patients with PDACs with this profile fared well after surgery. Based on this profile, we established a 6-28 gene tubulogenesis-specific signature that accurately determined the prognosis of independent cohorts of patients with PDAC (total n = 128; accuracy = 81.2%-95.0%). One gene, ASPM, was down-regulated during tubulogenesis but up-regulated in human PDAC cell lines and tumor samples; up-regulation correlated with patient outcomes (Cox regression P = .0028). Bioinformatic, genetic, biochemical, functional, and clinical correlative studies showed that ASPM promotes aggressiveness of PDAC by maintaining Wnt-ß-catenin signaling and stem cell features of PDAC cells. CONCLUSIONS: We identified a gene expression profile associated with pancreatic epithelial tubulogenesis and a tissue architecture-specific signature of PDAC cells that is associated with patient outcomes after surgery.