- Browse by Author
Browsing by Author "Glaser, Shannon S."
Now showing 1 - 5 of 5
Results Per Page
Sort Options
Item Modulation of the Tryptophan Hydroxylase 1/Monoamine Oxidase-A/5-Hydroxytryptamine/5-Hydroxytryptamine Receptor 2A/2B/2C Axis Regulates Biliary Proliferation and Liver Fibrosis During Cholestasis(Wiley, 2020-03) Kyritsi, Konstantina; Chen, Lixian; O’Brien, April; Francis, Heather; Hein, Travis W.; Venter, Julie; Wu, Nan; Ceci, Ludovica; Zhou, Tianhao; Zawieja, David; Gashev, Anatoliy A.; Meng, Fanyin; Invernizzi, Pietro; Fabris, Luca; Wu, Chaodong; Skill, Nicholas J.; Saxena, Romil; Liangpunsakul, Suthat; Alpini, Gianfranco; Glaser, Shannon S.; Medicine, School of MedicineBackground and aims: Serotonin (5HT) is a neuroendocrine hormone synthetized in the central nervous system (CNS) as well as enterochromaffin cells of the gastrointestinal tract. Tryptophan hydroxylase (TPH1) and monoamine oxidase (MAO-A) are the key enzymes for the synthesis and catabolism of 5HT, respectively. Previous studies demonstrated that 5-hydroxytryptamine receptor (5HTR)1A/1B receptor agonists inhibit biliary hyperplasia in bile-duct ligated (BDL) rats, whereas 5HTR2B receptor antagonists attenuate liver fibrosis (LF) in mice. Our aim was to evaluate the role of 5HTR2A/2B/2C agonists/antagonists in cholestatic models. Approach and results: While in vivo studies were performed in BDL rats and the multidrug resistance gene 2 knockout (Mdr2-/- ) mouse model of PSC, in vitro studies were performed in cell lines of cholangiocytes and hepatic stellate cells (HSCs). 5HTR2A/2B/2C and MAO-A/TPH1 are expressed in cholangiocytes and HSCs from BDL rats and Mdr2-/- - mice. Ductular reaction, LF, as well as the mRNA expression of proinflammatory genes increased in normal, BDL rats, and Mdr2-/- - mice following treatment 5HTR2A/2B/2C agonists, but decreased when BDL rats and Mdr2-/- mice were treated with 5HTR2A/2B/2C antagonists compared to BDL rats and Mdr2-/- mice, respectively. 5HT levels increase in Mdr2-/- mice and in PSC human patients compared to their controls and decrease in serum of Mdr2-/- mice treated with 5HTR2A/2B/2C antagonists compared to untreated Mdr2-/- mice. In vitro, cell lines of murine cholangiocytes and human HSCs express 5HTR2A/2B/2C and MAO-A/TPH1; treatment of these cell lines with 5HTR2A/2B/2C antagonists or TPH1 inhibitor decreased 5HT levels as well as expression of fibrosis and inflammation genes compared to controls. Conclusions: Modulation of the TPH1/MAO-A/5HT/5HTR2A/2B/2C axis may represent a therapeutic approach for management of cholangiopathies, including PSC.Item Molecular Mechanisms Linking Risk Factors to Cholangiocarcinoma Development(MDPI, 2022) Ceci, Ludovica; Zhou, Tianhao; Lenci, Ilaria; Meadows, Vik; Kennedy, Lindsey; Li, Ping; Ekser, Burcin; Milana, Martina; Zhang, Wenjun; Wu, Chaodong; Sato, Keisaku; Chakraborty, Sanjukta; Glaser, Shannon S.; Francis, Heather; Alpini, Gianfranco; Baiocchi, Leonardo; Medicine, School of MedicineThe poor prognosis of cholangiocarcinoma in humans is related to several factors, such as (i) the heterogeneity of the disease, (ii) the late onset of symptoms and (iii) the limited comprehension of the carcinogenic pathways determining neoplastic changes, which all limit the pursuit of appropriate treatment. Several risk factors have been recognized, including different infective, immune-mediated, and dysmorphogenic disorders of the biliary tree. In this review, we report the details of possible mechanisms that lead a specific premalignant pathological condition to become cholangiocarcinoma. For instance, during liver fluke infection, factors secreted from the worms may play a major role in pathogenesis. In primary sclerosing cholangitis, deregulation of histamine and bile-acid signaling may determine important changes in cellular pathways. The study of these molecular events may also shed some light on the pathogenesis of sporadic (unrelated to risk factors) forms of cholangiocarcinoma, which represent the majority (nearly 75%) of cases.Item Phosphorylation and Stabilization of PIN1 by JNK Promote Intrahepatic Cholangiocarcinoma Growth(Wiley, 2021) Lepore, Alessio; Choy, Pui Man; Lee, Nathan C. W.; Carella, Maria Annunziata; Favicchio, Rosy; Briones-Orta, Marco A.; Glaser, Shannon S.; Alpini, Gianfranco; D’Santos, Clive; Tooze, Reuben M.; Lorger, Mihaela; Syn, Wing-Kin; Papakyriakou, Athanasios; Giamas, Georgios; Bubici, Concetta; Papa, Salvatore; Medicine, School of MedicineBackground and aims: Intrahepatic cholangiocarcinoma (ICC) is a highly aggressive type of liver cancer in urgent need of treatment options. Aberrant activation of the c-Jun N-terminal kinase (JNK) pathway is a key feature in ICC and an attractive candidate target for its treatment. However, the mechanisms by which constitutive JNK activation promotes ICC growth, and therefore the key downstream effectors of this pathway, remain unknown for their applicability as therapeutic targets. Our aim was to obtain a better mechanistic understanding of the role of JNK signaling in ICC that could open up therapeutic opportunities. Approach and results: Using loss-of-function and gain-of-function studies in vitro and in vivo, we show that activation of the JNK pathway promotes ICC cell proliferation by affecting the protein stability of peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (PIN1), a key driver of tumorigenesis. PIN1 is highly expressed in ICC primary tumors, and its expression positively correlates with active JNK. Mechanistically, the JNK kinases directly bind to and phosphorylate PIN1 at Ser115, and this phosphorylation prevents PIN1 mono-ubiquitination at Lys117 and its proteasomal degradation. Moreover, pharmacological inhibition of PIN1 through all-trans retinoic acid, a Food and Drug Administration-approved drug, impairs the growth of both cultured and xenografted ICC cells. Conclusions: Our findings implicate the JNK-PIN1 regulatory axis as a functionally important determinant for ICC growth, and provide a rationale for therapeutic targeting of JNK activation through PIN1 inhibition.Item Targeting Lymphangiogenesis and Lymph Node Metastasis in Liver Cancer(Elsevier, 2021) Roy, Sukanya; Banerjee, Priyanka; Ekser, Burcin; Bayless, Kayla; Zawieja, David; Alpini, Gianfranco; Glaser, Shannon S.; Chakraborty, Sanjukta; Surgery, School of MedicineIncreased lymphangiogenesis and lymph node metastasis, the important prognostic indicators of aggressive hepatobiliary malignancies such as hepatocellular cancer and cholangiocarcinoma, are associated with poor patient outcome. The liver produces 25% to 50% of total lymphatic fluid in the body and has a dense network of lymphatic vessels. The lymphatic system plays critical roles in fluid homeostasis and inflammation and immune response. Yet, lymphatic vessel alterations and function are grossly understudied in the context of liver pathology. Expansion of the lymphatic network has been documented in clinical samples of liver cancer; and although largely overlooked in the liver, tumor-induced lymphangiogenesis is an important player, increasing tumor metastasis in several cancers. This review aims to provide a detailed perspective on the current knowledge of alterations in the hepatic lymphatic system during liver malignancies, as well as various molecular signaling mechanisms and growth factors that may provide future targets for therapeutic intervention. In addition, the review also addresses current mechanisms and bottlenecks for effective therapeutic targeting of tumor-associated lymphangiogenesis.Item Tumor Lymphatic Interactions Induce CXCR2-CXCL5 Axis and Alter Cellular Metabolism and Lymphangiogenic Pathways to Promote Cholangiocarcinoma(MDPI, 2021-11-09) Roy, Sukanya; Kumaravel, Subhashree; Banerjee, Priyanka; White, Tori K.; O’Brien, April; Seelig, Catherine; Chauhan, Rahul; Ekser, Burcin; Bayless, Kayla J.; Alpini, Gianfranco; Glaser, Shannon S.; Chakraborty, Sanjukta; Surgery, School of MedicineCholangiocarcinoma (CCA), or cancer of bile duct epithelial cells, is a very aggressive malignancy characterized by early lymphangiogenesis in the tumor microenvironment (TME) and lymph node (LN) metastasis which correlate with adverse patient outcome. However, the specific roles of lymphatic endothelial cells (LECs) that promote LN metastasis remains unexplored. Here we aimed to identify the dynamic molecular crosstalk between LECs and CCA cells that activate tumor-promoting pathways and enhances lymphangiogenic mechanisms. Our studies show that inflamed LECs produced high levels of chemokine CXCL5 that signals through its receptor CXCR2 on CCA cells. The CXCR2-CXCL5 signaling axis in turn activates EMT (epithelial-mesenchymal transition) inducing MMP (matrix metalloproteinase) genes such as GLI, PTCHD, and MMP2 in CCA cells that promote CCA migration and invasion. Further, rate of mitochondrial respiration and glycolysis of CCA cells was significantly upregulated by inflamed LECs and CXCL5 activation, indicating metabolic reprogramming. CXCL5 also induced lactate production, glucose uptake, and mitoROS. CXCL5 also induced LEC tube formation and increased metabolic gene expression in LECs. In vivo studies using CCA orthotopic models confirmed several of these mechanisms. Our data points to a key finding that LECs upregulate critical tumor-promoting pathways in CCA via CXCR2-CXCL5 axis, which further augments CCA metastasis.