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Monoclonal Antibodies Recognizing the Non-Tandem Repeat Regions of the Human Mucin MUC4 in Pancreatic Cancer  [PDF]
Maneesh Jain, Ganesh Venkatraman, Nicolas Moniaux, Sukhwinder Kaur, Sushil Kumar, Subhankar Chakraborty, Grish C. Varshney, Surinder K. Batra
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0023344
Abstract: The MUC4 mucin is a high molecular weight, membrane-bound, and highly glycosylated protein. It is a multi-domain protein that is putatively cleaved into a large mucin-like subunit (MUC4α) and a C-terminal growth-factor like subunit (MUC4β). MUC4 plays critical roles in physiological and pathological conditions and is aberrantly overexpressed in several cancers, including those of the pancreas, cervix, breast and lung. It is also a potential biomarker for the diagnosis, prognosis and progression of several malignancies. Further, MUC4 plays diverse functional roles in cancer initiation and progression as evident from its involvement in oncogenic transformation, proliferation, inhibition of apoptosis, motility and invasion, and resistance to chemotherapy in human cancer cells. We have previously generated a monoclonal antibody 8G7, which is directed against the TR region of MUC4, and has been extensively used to study the expression of MUC4 in several malignancies. Here, we describe the generation of anti-MUC4 antibodies directed against the non-TR regions of MUC4. Recombinant glutathione-S-transferase (GST)-fused MUC4α fragments, both upstream (MUC4α-N-Ter) and downstream (MUC4α-C-Ter) of the TR domain, were used as immunogens to immunize BALB/c mice. Following cell fusion, hybridomas were screened using the aforementioned recombinant proteins ad lysates from human pancreatic cell lines. Three anti MUC4α-N-Ter and one anti-MUC4α-C-Ter antibodies were characterized by several inmmunoassays including enzyme-linked immunosorbent assay (ELISA), immunoblotting, immunofluorescene, flow cytometry and immunoprecipitation using MUC4 expressing human pancreatic cancer cell lines. The antibodies also reacted with the MUC4 in human pancreatic tumor sections in immunohistochemical analysis. The new domain-specific anti-MUC4 antibodies will serve as important reagents to study the structure-function relationship of MUC4 domains and for the development of MUC4-based diagnostics and therapeutics.
Citrus jabara Extracts Suppress MUC5AC Mucin Production in Human Lung Epithelial Cells  [PDF]
Jun Iwashita, Naoki Iguchi, Akiko Takashima, Daisuke Watanabe, Kimihiko Sano, Masahiko Ishikuro, Keishi Hata, Jun Murata
Advances in Biological Chemistry (ABC) , 2017, DOI: 10.4236/abc.2017.73009
Abstract: In the human airway, the overproduction of MUC5AC mucin is a key feature of allergic asthma, and it induces airway narrowing and obstruction. The production of MUC5AC is regulated by several signals, but the mechanism is not completely understood. We investigated the effect of jabara, a citrus containing abundant flavonoids, on the regulation of MUC5AC production. When NCI-H292 human airway epithelial cells were cultured with jabara extracts, we found that the expression of Periodic acid-schiff stained mucin was suppressed with downregulated MUC5AC production. In human primary airway cells derived from asthmatic patients, MUC5AC production was also suppressed by jabara extracts. The treatment of cells with jabara extracts decreased ERK activation in NCI-H292 and in primary cells. These results show that jabara extracts contain some factors that suppress MUC5AC production and ERK activity and suggest that it will be useful for relieving asthma.
Nitric oxide induces MUC5AC mucin in respiratory epithelial cells through PKC and ERK dependent pathways
Jeong Song, Chun Kang, Moon Yoo, Seung Kim, Hyung Yoon, Young Kim, Kwan Kim, Hwa Moon, Sung Park
Respiratory Research , 2007, DOI: 10.1186/1465-9921-8-28
Abstract: Nitric oxide was donated to the A549 cells by NOR-1. MUC5AC mucin levels were assayed by enzyme-linked immunosorbent assay (ELISA). MUC5AC promoter activity was determined by measuring luciferase activity after the lysing the transfected cells. Activation of PKC isoforms were measured by assessing the distribution of the enzyme between cytosolic and membrane fractions using immunoblotting. Immunoblotting experiments using a monoclonal antibody specific to PKC isoforms were performed in the cytosol and membrane fractions from A549 cells. Western blot analysis for pERK and p38 were performed using the corresponding antibodies from the cell lysates after donating NO to the A549 cells by NOR-1.The transcriptional activity of MUC5AC promoter was maximal at the concentration of 0.1 mM NOR-1 for 1 hour incubation in transfected A549 cells. (±)-(E)-methyl-2-((E)-hydroxyimino)-5-nitro-6-methoxy-3-hexenamide (NOR-1) markedly displaced the protein kinase C (PKC)α and PKCδ from the cytosol to the membrane. Furthermore, the PKC-α,βinhibitors, G?6976 (10 nM) and PKCδ inhibitors, rottlerin (4 μM) inhibited the NOR-1 induced migration of PKCα and PKCδ respectively. NOR-1 also markedly increased the MUC5AC promoter activity and mRNA expression, mucin synthesis and ERK1/2 phosphorylation. The PKC inhibitors also inhibited the NOR-1 induced MUC5AC mRNA and MUC5AC protein synthesis by inhibiting the activation of PKCα and PKCδ with ERK1/2 pathways.Exogenous NO induced the MUC5AC mucin gene and protein through the PKCα and PKCδ – ERK pathways in A549 cells. Inhibition of PKC attenuated NO-mediated MUC5AC mucin synthesis. In view of this findings, PKC inhibitors might be useful in the treatment of bronchial asthma and chronic bronchitis patients where NO and mucus are increased in the bronchial airways.Production of NO is generally increased during inflammatory airway diseases such as asthma or bronchiectasis, or after exposure to irritant gases such as ozone [1]. NO is produced by the a
The MUC1 Cytoplasmic Tail and Tandem Repeat Domains Contribute to Mammary Oncogenesis in FVB Mice
Christine L. Hattrup,Judy M. Bradley,Kari L. Kotlarczyk,Cathy S. Madsen
Breast Cancer: Basic and Clinical Research , 2008,
Abstract: Background: Though the importance of the transmembrane mucin MUC1 in mammary oncogenesis has long been recognized, the relative contributions of the cytoplasmic tail and tandem repeat domains are poorly understood.Methods: To address this, mouse models of mammary carcinogenesis were created expressing full-length, cytoplasmic tail-deleted, or tandem repeat-deleted MUC1 constructs.Results: Overexpression of full-length MUC1 resulted in tumor formation in young mice (12 months); however, loss of either the cytoplasmic tail or the tandem repeat domain abrogated this oncogenic capacity. Aged mice in all strains developed late-onset mammary tumors similar to those previously described for the FVB background.Conclusions: This study is the fi rst spontaneous cancer model to address the relative importance of the cytoplasmic tail and tandem repeat domains to MUC1-driven mammary oncogenesis, and suggests that both of these domains are essential for tumor formation.
Humoral immune response to MUC5AC in patients with colorectal polyps and colorectal carcinoma
Belma Kocer, John McKolanis, Atilla Soran
BMC Gastroenterology , 2006, DOI: 10.1186/1471-230x-6-4
Abstract: Free circulating MUC5AC antibodies were measured using an enzyme-linked immunosorbent assay with a synthetic peptide corresponding to an 8 aa. segment of MUC5AC tandem repeat region. Immunohistochemical analysis was completed to demonstrate MUC5AC expression in the polyp specimens.MUC5AC antibodies were detected in 6 of 22 (27.3%) healthy subjects, 9 of 20 (45%) polyp patients, 18 of 30 (60%) patients with colorectal cancer. The presence of circulating free MUC5AC antibody levels was significantly correlated with expression of MUC5AC in polyp sections. Serum MUC5AC antibody positivity was higher in patients with colon located tumors, advanced stage and poorly differentiated tumors were found negatively affecting patient survival in our study. MUC5AC antibody positivity was higher in patients with poor prognostic parameters. Disease free survival and overall survival were shorter in this group of patients. In the multivariate analysis MUC5AC antibody positivity didn't find an independent prognostic factor on prognosis.Decreased survival in colorectal carcinoma patients with MUC5AC antibody positivity may be due to a decrease in the MUC5AC expression in tumor tissues of surviving carcinoma patients.Mucins are high molecular weight glycoproteins with O-linked oligosaccharides attached to serine or threonine residues of the apomucin protein backbone [1]. To date, 19 genes coding for apomucin have been identified [2-5]. Mucins are expressed with a cell and tissue-specific pattern in normal tissues [6,7]. There are two structurally and functionally distinct classes of mucins; secreted gel-forming mucins and transmembrane mucins. Secreted gel-forming mucins include the products of the MUC2, MUC5AC, MUC5B and MUC6 genes on chromosome 11p15.5 [8-10]. Each has a central region with a variable number of tandem repeat (VNRT), but there is a little similarity. MUC5AC was cloned from tracheobronchial [11] and stomach [12] cDNA libraries. Tandem repeat units have eight amino acid
PKCθ Synergizes with TLR-Dependent TRAF6 Signaling Pathway to Upregulate MUC5AC Mucin via CARMA1  [PDF]
Hirofumi Jono, Jae Hyang Lim, Haidong Xu, Jian-Dong Li
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0031049
Abstract: CARD-containing MAGUK protein 1 (CARMA1) plays a crucial role in regulating adaptive immune responses upon T-cell receptor (TCR) activation in T cells. Its role in regulating host mucosal innate immune response such as upregulation of mucin remains unknown. Here we show that CARMA1 acts as a key signaling mediator for synergistic upregulation of MUC5AC mucin by bacterium nontypeable Haemophilus influenzae (NTHi) and phorbol ester PMA in respiratory epithelial cells. NTHi-induced TLR-dependent TRAF6-MKK3-p38 MAPK signaling pathway synergizes with PKCθ-MEK-ERK signaling pathway. CARMA1 plays a crucial role in mediating this synergistic effect via TRAF6, thereby resulting in synergistic upregulation of MUC5AC mucin. Thus our study unveils a novel role for CARMA1 in mediating host mucosal innate immune response.
RNA interference suppression of mucin 5AC (MUC5AC) reduces the adhesive and invasive capacity of human pancreatic cancer cells
Sadaaki Yamazoe, Hiroaki Tanaka, Tetsuji Sawada, Ryosuke Amano, Nobuya Yamada, Masaichi Ohira, Kosei Hirakawa
Journal of Experimental & Clinical Cancer Research , 2010, DOI: 10.1186/1756-9966-29-53
Abstract: We used two MUC5AC expressing cell lines derived from human pancreatic cancer, SW1990 and BxPC3. Small-interfering (si) RNA directed against MUC5AC were used to assess the effects of MUC5AC on invasion and adhesion of pancreas cancer cells in vitro and in vivo. We compared parental cells (SW1990 and BxPC3) with MUC5AC suppressed cells by si RNA (si-SW1990 and si-BxPC3).MUC5AC was found to express in more than 80% of pancreatic ductal carcinoma specimens. Next we observed that both of si-SW1990 and si-BxPC3 showed significantly lower adhesion and invasion to extracellular matrix components compared with parental cell lines. Expression of genes associated with adhesion and invasion including several integerins, matrix metalloproteinase (MMP) -3 and vascular endothelial growth factor (VEGF) were down-regulated in both MUC5AC suppressed cells. Furthermore, production of VEGF and phosphorylation of VEGFR-1 were significantly reduced by MUC5AC down regulation. Both of si-SW1990 and si-BxPC3 attenuated activation of Erk1/2. In vivo, si-SW1990 did not establish subcutaneous tumor in nude mice.Knockdown of MUC5AC reduced the ability of pancreatic cancer cells to adhesion and invasion, suggesting that MUC5AC might contribute to the invasive motility of pancreatic cancer cells by enhancing the expression of integrins, MMP-3, VEGF and activating Erk pathway.Pancreatic cancer has a poor prognosis; the 5-year survival rate in only 3% and the median survival rate is only 6 months[1]. It is also associated with aggressive cancer cells, and metastatic disease that results from a lack of early-stage diagnostic methods and effective therapies. Adhesiveness and invasiveness of cancer cells play a central role in pancreatic cancer progression [2,3]. Mucins are highly glycosylated glycoproteins that are the major components of the viscous mucous gel covering the surface of epithelial tissues [4]. Changes in mucin expression or glycosylation accompany the development of cancer and influen
Methods of Finding Tandem Repeat in String
Tandem repeat查找方法比较

XU Heng-Yu,WANG Di,WANG Guo-Ren,ZHENG Ruo-Shi School of Information Science & Engineering,Northeastern University,Shenyang,
徐恒宇
,王镝,王国仁,郑若石

计算机科学 , 2005,
Abstract: Tandem repeat takes such an important role in gene composition and evolution that the search and analysis of tandem repeat have become one of the front domain and research focus. There are multiple methods in recent works, mainly including two methods. One is based on LZ decomposition, and the other is based on suffix tree index. This pa- per summarize these two O(nlogn) methods and takes a thorough analysis and comparison of their performance.
Polysaccharides and mucin 5AC (MUC5AC) expression in gallbladder mucosa of young patients with gallstones as evaluated by spatial visualization and quantification  [PDF]
Aldona Kasprzak,Wojciech Malkowski,Celina Helak-£apaj,Agnieszka Seraszek
Folia Histochemica et Cytobiologica , 2010,
Abstract: The study aimed at examination of tissue expression of polysaccharides and secretory mucin 5AC (MUC5AC)in young patients (up to 25 years of age) with a symptomatic gallstones. For comparison, patients most frequently subjectedto cholecystectomy were studied, i.e. patients of approximately 50 years of age with the same diagnosis. In quantitativestudies on tissue expression of both mucus components, the modern technique of spatial visualization was applied for thefirst time. Application of the technique permitted to demonstrate significant positive relationships between expression ofglycoproteins (immunocytochemical ABC technique for detection of MUC5AC) and expression of sugar components inmucus (PAS technique) and to confirm suitability of the technique for quantitative appraisal of both histochemical andimmunocytochemical reactions. An even higher expression of polysaccharides in the entire mucosa and of MUC5AC wasdetected in gallbladder epithelium of 50-year-old patients, as compared to young patients with symptomatic gallstones. Inthe young patients, expression of polysaccharides correlated with inflammatory activity (grading), width of gallbladder walland PLT level in peripheral blood. A significantly higher expression of polysaccharides in gallbladder epithelium wasdemonstrated in young patients admitted in the emergency mode to the hospital. These correlations in young patients maysuggest a role of both mucus components in pathogenesis of cholelithiasis in this age group. A quantitative appraisal ofmucus component expression in the two parts of gallbladder mucosa (epithelium vs. entire mucosa) using spatial visualizationtechnique permitted to more accurately compare production of glycoproteins and of polysaccharides in patients withcholelithiasis and to demonstrate additional correlations of a potential clinical significance.
Polysaccharides and mucin 5AC (MUC5AC) expression in gallbladder mucosa of young patients with gallstones as evaluated by spatial visualization and quantification.  [cached]
Aldona Kasprzak,Wojciech Malkowski,Celina Helak-?apaj,Agnieszka Seraszek
Folia Histochemica et Cytobiologica , 2011, DOI: 10.5603/4179
Abstract: The study aimed at examination of tissue expression of polysaccharides and secretory mucin 5AC (MUC5AC) in young patients (up to 25 years of age) with a symptomatic gallstones. For comparison, patients most frequently subjected to cholecystectomy were studied, i.e. patients of approximately 50 years of age with the same diagnosis. In quantitative studies on tissue expression of both mucus components, the modern technique of spatial visualization was applied for the first time. Application of the technique permitted to demonstrate significant positive relationships between expression of glycoproteins (immunocytochemical ABC technique for detection of MUC5AC) and expression of sugar components in mucus (PAS technique) and to confirm suitability of the technique for quantitative appraisal of both histochemical and immunocytochemical reactions. An even higher expression of polysaccharides in the entire mucosa and of MUC5AC was detected in gallbladder epithelium of 50-year-old patients, as compared to young patients with symptomatic gallstones. In the young patients, expression of polysaccharides correlated with inflammatory activity (grading), width of gallbladder wall and PLT level in peripheral blood. A significantly higher expression of polysaccharides in gallbladder epithelium was demonstrated in young patients admitted in the emergency mode to the hospital. These correlations in young patients may suggest a role of both mucus components in pathogenesis of cholelithiasis in this age group. A quantitative appraisal of mucus component expression in the two parts of gallbladder mucosa (epithelium vs. entire mucosa) using spatial visualization technique permitted to more accurately compare production of glycoproteins and of polysaccharides in patients with cholelithiasis and to demonstrate additional correlations of a potential clinical significance.
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