Supplementary Figure 1 from Global Hypomethylation of Genomic DNA in Cancer-Associated Myofibroblasts

Supplementary Figure 3 from Global Hypomethylation of Genomic DNA in Cancer-Associated Myofibroblasts

Supplementary Figure 2 from Global Hypomethylation of Genomic DNA in Cancer-Associated Myofibroblasts

Stromal cells influence epithelial function in both health and disease. Myofibroblasts are abundant stromal cells that influence the cellular microenvironment by release of extracellular matrix (ECM) proteins, growth factors, proteases, cytokines, and chemokines. Cancer-associated myofibroblasts (CAMs) differ from adjacent tissue (ATMs) and normal tissue myofibroblasts (NTMs), but the basis of this is incompletely understood. We report now the differential expression of miRNAs in gastric cancer CAMs. MicroRNA arrays identified differences in the miRNA profile in gastric and esophageal NTMs and in CAMs from stomach compared with NTMs. miR-181d was upregulated in gastric CAMs. Analysis of differentially regulated miRNAs indicated an involvement in Wnt signaling. Examination of a microarray data set then identified Wnt5a as the only consistently upregulated Wnt ligand in gastric CAMs. Wnt5a stimulated miR-181d expression, and knockdown of miR-181d inhibited Wnt5a stimulation of CAM proliferation and migration. Analysis of miR-181d targets suggested a role in chemotaxis. Conditioned medium from CAMs stimulated gastric cancer cell (AGS) migration more than that from ATMs, and miR-181d knockdown reduced the effect of CAM-CM on AGS cell migration but had no effect on AGS cell responses to ATM conditioned media. The data suggest that dysregulation of miRNA expression in gastric CAMs, secondary to Wnt5a signaling, accounts at least in part for the effect of CAMs in promoting cancer cell migration.

Background: Gastroesophageal reflux (GER) has been associated with pulmonary disease in pre-lung transplant patients, especially idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD).The mechanism of these associations remains controversial.Microaspiration of refluxate may lead to inflammatory changes and pulmonary fibrosis or airway disease.Worsening pulmonary function may also increase trans-diaphragmatic pressure gradient, magnifying GER.The association between GER and decline in lung function in these patients has not yet been demonstrated.Evaluating the relationship between objective reflux parameters and change in pulmonary function may help clarify pathophysiology and identify targets for treatment.Aim: To investigate the association between objective measures of reflux on multichannel intraluminal impedance and pH study (MII-pH) and change in pulmonary function testing (PFT) parameters over one year, in pre-lung transplant patients with IPF or COPD.Methods: This was a retrospective cohort study of adults with IPF or COPD who underwent pre-transplant evaluation with MII-pH, off acid suppression, at a tertiary care center from 6/2010-14.Patients with fundoplication prior to MII-pH were excluded.PFT was performed within 1 month of MII-pH and at 12-month follow-up.Association between baseline reflux measures and change in PFT parameters over one year was evaluated using Student's t-test for continuous variables and Fisher's exact test for binary variables.Results: 57 subjects (mean age=60 yrs, 42% female, 37 IPF vs 20 COPD) met criteria for inclusion.Among IPF patients, abnormal bolus reflux on impedance was associated with a significant decline in forced expiratory volume in 1 second (FEV1) in 1 year (-0.048L/sec vs +0.24 L/sec, p=0.041), as was increased acid exposure time (-0.195L/sec vs +0.144 L/sec, p=0.05).Trends toward more severe decline in forced vital capacity (FVC) in 1year for both abnormal bolus reflux (-0.085L/sec vs +0.25 L/sec, p=0.09) and increased acid exposure time (-0.28L/sec vs +0.147 L/sec, p=0.10) were also observed.Among COPD patients, trends toward more severe decline in FEV1 in 1 year was noted for increased acid exposure time (-0.27L/sec vs -0.035 L/sec, p=0.087).No other significant associations between change in PFT and abnormal MII-pH parameters were found (Table 1).Conclusion: Abnormal GER as measured on MII-pH predicts more severe decline in lung function in 1 year on PFT among pre-lung transplant patients with IPF.A similar association between GER and lung function decline was not found in COPD patients.GER may play a more significant role in the pathogenesis of IPF than COPD.Future long-term studies are needed to further characterize the effect of GER on severity and prognosis of pulmonary disorders.Association between measures of reflux severity and worse pulmonary function (FEV1) after 1 year in patients with IPF.

The pyloric antral hormone gastrin plays a role in remodeling of the gastric epithelium, but the specific targets of gastrin that mediate these effects are poorly understood. Glandular epithelial cells of the gastric corpus express matrix metalloproteinase (MMP)-1, which is a potential determinant of tissue remodeling; some of these cells express the CCK-2 receptor at which gastrin acts. We have now examined the hypothesis that gastrin stimulates expression of MMP-1 in the stomach. We determined MMP-1 transcript abundance in gastric mucosal biopsies from Helicobacter pylori negative human subjects with normal gastric mucosal histology, who had a range of serum gastrin concentrations due in part to treatment with proton pump inhibitors (PPI). The effects of gastrin were studied on gastric epithelial AGS-GR cells using Western blot and migration assays. In human subjects with increased serum gastrin due to PPI usage, MMP-1 transcript abundance was increased 2-fold; there was also increased MMP-7 transcript abundance but not MMP-3. In Western blots, gastrin increased proMMP-1 abundance, as well that of a minor band corresponding to active MMP-1, in the media of AGS-GR cells, and the response was mediated by protein kinase C and p42/44 MAP kinase. There was also increased MMP-1 enzyme activity. Gastrin-stimulated AGS-GR cell migration in both scratch wound and Boyden chamber assays was inhibited by MMP-1 immunoneutralization. We conclude that MMP-1 expression is a target of gastrin implicated in mucosal remodeling.

Stromal cells such as myofibroblasts influence tumor progression. The mechanisms are unclear but may involve effects on both tumor cells and recruitment of bone marrow-derived mesenchymal stromal cells (MSCs) which then colonize tumors. Using iTRAQ and LC-MS/MS we identified the adipokine, chemerin, as overexpressed in esophageal squamous cancer associated myofibroblasts (CAMs) compared with adjacent tissue myofibroblasts (ATMs). The chemerin receptor, ChemR23, is expressed by MSCs. Conditioned media (CM) from CAMs significantly increased MSC cell migration compared to ATM-CM; the action of CAM-CM was significantly reduced by chemerin-neutralising antibody, pretreatment of CAMs with chemerin siRNA, pretreatment of MSCs with ChemR23 siRNA, and by a ChemR23 receptor antagonist, CCX832. Stimulation of MSCs by chemerin increased phosphorylation of p42/44, p38 and JNK-II kinases and inhibitors of these kinases and PKC reversed chemerin-stimulated MSC migration. Chemerin stimulation of MSCs also induced expression and secretion of macrophage inhibitory factor (MIF) that tended to restrict migratory responses to low concentrations of chemerin but not higher concentrations. In a xenograft model consisting of OE21 esophageal cancer cells and CAMs, homing of MSCs administered i.v. was inhibited by CCX832. Thus, chemerin secreted from esophageal cancer myofibroblasts is a potential chemoattractant for MSCs and its inhibition may delay tumor progression.

Stromal cells influence cancer progression. Myofibroblasts are an important stromal cell type, which influence the tumour microenvironment by release of extracellular matrix (ECM) proteins, proteases, cytokines and chemokines. The mechanisms of secretion are poorly understood. Here, we describe the secretion of marker proteins in gastric cancer and control myofibroblasts in response to insulin-like growth factor (IGF) stimulation and, using functional genomic approaches, we identify proteins influencing the secretory response. IGF rapidly increased myofibroblast secretion of an ECM protein, TGFβig-h3. The secretory response was not blocked by inhibition of protein synthesis and was partially mediated by increased intracellular calcium (Ca2+). The capacity for evoked secretion was associated with the presence of dense-core secretory vesicles and was lost in cells from patients with advanced gastric cancer. In cells responding to IGF-II, the expression of neuroendocrine marker proteins, including secretogranin-II and proenkephalin, was identified by gene array and LC-MS/MS respectively, and verified experimentally. The expression of proenkephalin was decreased in cancers from patients with advanced disease. Inhibition of secretogranin-II expression decreased the secretory response to IGF, and its over-expression recovered the secretory response consistent with a role in secretory vesicle biogenesis. We conclude that normal and some gastric cancer myofibroblasts have a neuroendocrine-like phenotype characterized by Ca2+-dependent regulated secretion, dense-core secretory vesicles and expression of neuroendocrine marker proteins; loss of the phenotype is associated with advanced cancer. A failure to regulate myofibroblast protein secretion may contribute to cancer progression.

BACKGROUND:Type-1 gastric neuroendocrine tumours (NETs) arise in some patients with chronic hypergastrinaemia secondary to autoimmune atrophic gastritis. Patients with small tumours are usually managed conservatively, because their prognosis is very good. However, larger tumours may require surgical intervention. Many type-1 gastric NETs regress following antrectomy because this removes the source of hypergastrinaemia. However, some tumours do not regress following antrectomy and additional surgery may be required. An octreotide suppression test has been previously suggested as a means to assess whether type-1 gastric NETs are likely to regress following antrectomy.AIM:To prospectively examine the role of a short-term intravenous octreotide suppression test in predicting type-1 gastric NET regression in five patients who subsequently underwent antrectomy.MATERIALS AND METHODS:Serum gastrin concentrations and gastric corpus and tumour histidine decarboxylase mRNA abundances were assessed in patients with type-1 gastric NETs before and 72 h after the administration of 25 µg/h intravenous octreotide. Gastric tumour response was assessed endoscopically following subsequent antrectomy.RESULTS:All patients showed significant decreases in serum gastrin concentrations as well as corpus and tumour biopsy histidine decarboxylase mRNA abundance following octreotide infusion. All patients also showed resolution of hypergastrinaemia following subsequent antrectomy. However, tumour regression was only observed in four of the five patients. One patient had a persistent tumour 3 years after antrectomy and required additional surgical resection.CONCLUSION:A positive octreotide suppression test result does not always predict response to antrectomy in patients with type-1 gastric NETs. Assessment of gastric mucosal responses to a gastrin/CCK-2 receptor antagonist may therefore also be helpful.

INTRODUCTION:Autoimmune chronic atrophic gastritis (CAG) causes hypochlorhydria and hypergastrinaemia, which can lead to enterochromaffin-like (ECL) cell hyperplasia and gastric neuroendocrine tumours (type 1 gastric NETs). Most behave indolently, but some larger tumours metastasise. Antrectomy, which removes the source of the hypergastrinaemia, usually causes tumour regression. Non-clinical and healthy-subject studies have shown that netazepide (YF476) is a potent, highly selective and orally-active gastrin/CCK-2 receptor antagonist. Also, it is effective in animal models of ECL-cell tumours induced by hypergastrinaemia.AIM:To assess the effect of netazepide on tumour biomarkers, number and size in patients with type I gastric NETs.METHODS:We studied 8 patients with multiple tumours and raised circulating gastrin and chromogranin A (CgA) concentrations in an open trial of oral netazepide for 12 weeks, with follow-up 12 weeks later. At 0, 6, 12 and 24 weeks, we carried out gastroscopy, counted and measured tumours, and took biopsies to assess abundances of several ECL-cell constituents. At 0, 3, 6, 9, 12 and 24 weeks, we measured circulating gastrin and CgA and assessed safety and tolerability.RESULTS:Netazepide was safe and well tolerated. Abundances of CgA (p<0.05), histidine decarboxylase (p<0.05) and matrix metalloproteinase-7(p<0.10) were reduced at 6 and 12 weeks, but were raised again at follow-up. Likewise, plasma CgA was reduced at 3 weeks (p<0.01), remained so until 12 weeks, but was raised again at follow-up. Tumours were fewer and the size of the largest one was smaller (p<0.05) at 12 weeks, and remained so at follow-up. Serum gastrin was unaffected.CONCLUSION:The reduction in abundances, plasma CgA, and tumour number and size by netazepide show that type 1 NETs are gastrin-dependent tumours. Failure of netazepide to increase serum gastrin further is consistent with achlorhydria. Netazepide is a potential new treatment for type 1 NETs. Longer, controlled trials are justified.TRIAL REGISTRATION:European Union EudraCT database 2007-002916-24 https://www.clinicaltrialsregister.eu/ctr-search/search?query=2007-002916-24ClinicalTrials.gov NCT01339169 http://clinicaltrials.gov/ct2/show/NCT01339169?term=yf476&rank=5.

Gastric mucosal health is maintained in response to potentially damaging luminal factors. Aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) disrupt protective mechanisms leading to bleeding and ulceration. The plasminogen activator system has been implicated in fibrinolysis following gastric ulceration, and an inhibitor of this system, plasminogen activator inhibitor (PAI)-1, is expressed in gastric epithelial cells. In Helicobacter pylori-negative patients with normal gastric histology taking aspirin or NSAIDs, we found elevated gastric PAI-1 mRNA abundance compared with controls; the increase in patients on aspirin was independent of whether they were also taking proton pump inhibitors. In the same patients, aspirin tended to lower urokinase plasminogen activator mRNA. Immunohistochemistry indicated PAI-1 localization to epithelial cells. In a model system using MKN45 or AGS-G R cells transfected with a PAI-1 promoter-luciferase reporter construct, we found no evidence for upregulation of PAI-1 expression by indomethacin, and, in fact, cyclooxygenase products such as PGE 2 and PGI 2 weakly stimulated expression. Increased gastric PAI-1 mRNA was also found in mice following gavage with ethanol or indomethacin, but plasma PAI-1 was unaffected. In PAI-1 −/− mice, gastric hemorrhagic lesions in response to ethanol or indomethacin were increased compared with C57BL/6 mice. In contrast, in PAI-1-H/Kβ mice in which PAI-1 is overexpressed in parietal cells, there were decreased lesions in response to ethanol and indomethacin. Thus, PAI-1 expression is increased in gastric epithelial cells in response to mucosal irritants such as aspirin and NSAIDs probably via an indirect mechanism, and PAI-1 acts as a local autoregulator to minimize mucosal damage.

was recorded at termination.Blood was collected for determination of serum gastrin.The histological changes in the stomachs were examined.The presence of dysplasia and carcinoma on the anterior and posterior side of the stomachs were compared, and the oxyntic mucosal thickness and neuroendocrine (chromogranin A positive) cell density were calculated.Results: Ten of fifteen animals operated by anterior vagotomy and 11 of 16 sham-operated developed hypergastrinemia.Vagotomy did not affect intragastric pH or serum gastrin.There was no difference between innervated and denervated oxyntic mucosa in dysplasia and carcinoma development.However, vagotomy resulted in lower stomach weight in hypergastrinemic animals (2.8 ± 0.26 g vs. 3.7 ± 0.39 g, p=0.027) and reduced oxyntic mucosal thickness on the anterior side (0.83 ± 0.06 mm vs. 1.13 ± 0.1 mm, p ,0.01).Vagotomy also resulted in a reduction in volume density of chromogranin A positive cells in the oxyntic mucosa (12.1 ± 1.8 % vs. 18.8 ± 3.0 %, p=0.04).Conclusions: Unilateral truncal vagotomy reduced the trophic effects of hypergastrinemia on the ECL cell and oxyntic mucosa, but did not prevent gastric carcinogenesis in female Japanese cotton rats.The effects of vagotomy on gastric carcinogenesis in animal models are conflicting and further studies in patients should be done to clarify the clinically significant effects of vagotomy.

to 11 out of 14 (79%).In five cases (3 adenomas and 2 carcinomas) the total number of mutant alleles changed.Pancreas: Digital PCR increased the number of mutated cases from 26 (62%) to 34 (81%).While conventional PCR depicted the presence of multiple KRAS alleles in 12 cases, digital PCR depicted two or more mutant alleles in 25 cases.A good correlation was observed between tumor biopsies and pancreatic juice.Conclusions: Digital PCR provides a robust and quantitative measure of KRAS mutant allele that can be used in routinely obtained samples.The use of this methodology allows a better classification of tumors that may be clinically relevant.

Tumor progression has been linked to changes in the stromal environment. Myofibroblasts are stromal cells that are often increased in tumors but their contribution to cancer progression is not well understood. Here, we show that the secretomes of myofibroblasts derived from gastric cancers [cancer-associated myofibroblasts (CAMs)] differ in a functionally significant manner from those derived from adjacent tissue [adjacent tissue myofibroblasts (ATMs)]. CAMs showed increased rates of migration and proliferation compared with ATMs or normal tissue myofibroblasts (NTMs). Moreover, conditioned medium (CM) from CAMs significantly stimulated migration, invasion and proliferation of gastric cancer cells compared with CM from ATMs or NTMs. Proteomic analysis of myofibroblast secretomes revealed decreased abundance of the extracellular matrix (ECM) adaptor protein like transforming growth factor-β-induced gene-h3 (TGFβig-h3) in CAMs, which was correlated with lymph node involvement and shorter survival. TGFβig-h3 inhibited IGF-II-stimulated migration and proliferation of both cancer cells and myofibroblasts, and suppressed IGF-II activation of p42/44 MAPkinase; TGFβig-h3 knockdown increased IGF-II- and CM-stimulated migration. Furthermore, administration of TGFβig-h3 inhibited myofibroblast-stimulated growth of gastric cancer xenografts. We conclude that stromal cells exert inhibitory as well as stimulatory effects on tumor cells; TGFβig-h3 is a stromal inhibitory factor that is decreased with progression of gastric cancers.

lesions was the antrum (59%) and body (29%).Endoscopic follow-up was available for 116/161 patients; Forty patients had an endoscopic (n=33) or surgical (n=7) intervention and seventy-six patients underwent endoscopic follow-up only for their dysplasia.Thirteen of seventy-six (17%) were diagnosed with cancer within 12 months (mean 1.5 ± 1.4 months) of the index endoscopy (likely a misclassified lesion at diagnosis), having initially been classified as HGD in 69%, LGD in 23%, and indefinite for dysplasia in 7.7%.A further six patients progressed to gastric cancer after a mean of 3.8 ± 3.0 years (1.6 -10 years).There were initially 42 cases classified as indefinite for dysplasia at the index endoscopy.Following review, 50% (n=21) remained unchanged, 24% (n=10) were classified as reactive changes or absent dysplasia, 21.4% (n=9) classified as LGD and 4.8% (n=2) classified as HGD.Five of these cases developed a cancer over the study period.Conclusions: i) The majority of cases of gastric dysplasia were associated with an endoscopic lesions ii) There is a high rate of diagnosis of early cancer likely to represent an initial misinterpretation or sampling error, especially with HGD at index endoscopy iii) Overall rates of progression to cancer in this study are significantly lower than reported rates in Asian populations iv) Indefinite for dysplasia is not a benign finding and requires dedicated GI pathologists review.

Plasminogen activator inhibitor (PAI)-1 is associated with cancer progression, fibrosis and thrombosis. It is expressed in the stomach but the mechanisms controlling its expression there, and its biological role, are uncertain. We sought to define the role of gastrin in regulating PAI-1 expression and to determine the relevance for gastrin-stimulated cell migration and invasion. In gastric biopsies from subjects with elevated plasma gastrin, the abundances of PAI-1, urokinase plasminogen activator (uPA), and uPA receptor (uPAR) mRNAs measured by quantitative PCR were increased compared with subjects with plasma concentrations in the reference range. In patients with hypergastrinemia due to autoimmune chronic atrophic gastritis, there was increased abundance of PAI-1, uPA, and uPAR mRNAs that was reduced by octreotide or antrectomy. Immunohistochemistry revealed localization of PAI-1 to parietal cells and enterochromaffin-like cells in micronodular neuroendocrine tumors in hypergastrinemic subjects. Transcriptional mechanisms were studied by using a PAI-1-luciferase promoter-reporter construct transfected into AGS-GR cells. There was time- and concentration-dependent increase of PAI-1-luciferase expression in response to gastrin that was reversed by inhibitors of the PKC and MAPK pathways. In Boyden chamber assays, recombinant PAI-1 inhibited gastrin-stimulated AGS-GR cell migration and invasion, and small interfering RNA treatment increased responses to gastrin. We conclude that elevated plasma gastrin concentrations are associated with increased expression of gastric PAI-1, which may act to restrain gastrin-stimulated cell migration and invasion.

Myofibroblasts play central roles in wound healing, deposition of the extracellular matrix and epithelial function. Their functions depend on migration and proliferation within the subepithelial matrix, which results in accelerated cellular metabolism. Upregulated metabolic pathways generate protons which need to be excreted to maintain intracellular pH (pHi). We isolated human gastric myofibroblasts (HGMs) from surgical specimens of five patients. Then we characterized, for the first time, the expression and functional activities of the Na+/H+ exchanger (NHE) isoforms 1, 2 and 3, and the functional activities of the Na+/HCO 3 − cotransporter (NBC) and the anion exchanger (AE) in cultured HGMs using microfluorimetry, immunocytochemistry, reverse transcription polymerase chain reaction and immunoblot analysis. We showed that NHE1–3, NBC and AE activities are present in HGMs and that NHE1 is the most active of the NHEs. In scratch wound assays we also demonstrated (using the selective NHE inhibitor HOE-642) that carbachol and insulin like growth factor II (IGF-II) partly stimulate migration of HGMs in a NHE1-dependent manner. EdU incorporation assays revealed that IGF-II induces proliferation of HGMs which is inhibited by HOE-642. The results indicate that NHE1 is necessary for IGF-II-induced proliferation response of HGMs. Overall, we have characterized the pHi regulatory mechanisms of HGMs. In addition, we demonstrated that NHE1 activity contributes to both IGF-II- and carbachol-stimulated migration and that it is obligatory for IGF-II-induced proliferation of HGMs.