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ABSTRACT: There is an urgent need to develop alternative therapies against lethal pancreatic cancer (PC). Ocimum sanctum ("Holy Basil") has been used for thousands of years in traditional Indian medicine, but its anti-tumorigenic effect remains largely unexplored. Here, we show that extracts of O. sanctum leaves inhibit the proliferation, migration, invasion, and induce apoptosis of PC cells in vitro. The expression of genes that promote the proliferation, migration and invasion of PC cells including activated ERK-1/2, FAK, and p65 (subunit of NF-κB), was downregulated in PC cells after O. sanctum treatment. Intraperitoneal injections of the aqueous extract significantly inhibited the growth of orthotopically transplanted PC cells in vivo (p<0.05). Genes that inhibit metastasis (E-cadherin) and induce apoptosis (BAD) were significantly upregulated in tumors isolated from mice treated with O. sanctum extracts, while genes that promote survival (Bcl-2 and Bcl-xL) and chemo/radiation resistance (AURKA, Chk1 and Survivin) were downregulated. Overall, our study suggests that leaves of O. sanctum could be a potential source of novel anticancer compounds in the future.
Cancer letters 03/2013; · 4.86 Impact Factor
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Prabin Dhangada Majhi,
Imayavaramban Lakshmanan,
Moorthy P Ponnusamy,
Maneesh Jain,
Srustidhar Das, Sukhwinder Kaur,
Su Tomohiro Shimizu,
William W West,
Sonny L Johansson,
Lynette M Smith,
Fang Yu,
Cleo E Rolle,
Poonam Sharma,
George B Carey,
Surinder K Batra,
Apar Kishor Ganti
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ABSTRACT: INTRODUCTION:: Altered expression of MUC4 plays an oncogenic role in various cancers, including pancreatic, ovarian, and breast. This study evaluates the expression and role of MUC4 in non-small-cell lung cancer (NSCLC). METHODS:: We used a paired system of MUC4-expressing (H292) and MUC4-nonexpressing (A549) NSCLC cell lines to analyze MUC4-dependent changes in growth rate, migration, and invasion using these sublines. We also evaluated the alterations of several tumor suppressor, proliferation, and metastasis markers with altered MUC4 expression. Furthermore, the association of MUC4 expression (by immunohistochemistry) in lung cancer samples with patient survival was evaluated. RESULTS:: MUC4-expressing lung cancer cells demonstrated a less proliferative and metastatic phenotype. Up-regulation of p53 in MUC4-expressing lung cancer cells led to the accumulation of cells at the G2/M phase of cell cycle progression. MUC4 expression attenuated Akt activation and decreased the expression of Cyclins D1 and E, but increased the expression of p21 and p27. MUC4 expression abrogated cancer cell migration and invasion by altering N- & E-cadherin expression and FAK phosphorylation. A decrease in MUC4 expression was observed with increasing tumor stage (mean composite score: stage I, 2.4; stage II, 1.8; stage III, 1.4; and metastatic, 1.2; p = 0.0093). Maximal MUC4 expression was associated with a better overall survival (p = 0.042). CONCLUSION:: MUC4 plays a tumor-suppressor role in NSCLC by altering p53 expression in NSCLC. Decrease in MUC4 expression in advanced tumor stages also seems to confirm the novel protective function of MUC4 in NSCLC.
Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 01/2013; · 4.55 Impact Factor
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ABSTRACT: Immunohistochemistry (IHC) is a valuable tool to visualize the distribution and localization of specific cellular components within morphologically preserved tissue sections or cell preparations. It combines the histologic morphology of tissues for detecting the actual antigen distribution, specificity of antibody-antigen interaction for optimal detection, and sensitivity of immunochemical methods for assessing the amount of antigen in tissues. It is routinely used clinically to diagnose type (benign or malignant), stage, and grade of cancer using specific tumor markers. The application of IHC ranges from disease diagnosis and prognosis to drug development and analysis of the pathobiological roles of various molecular players during disease development. Due to better availability of highly specific antibodies and optimal methodologies for performing immunohistochemical studies, IHC is being used at an expanding rate to understand pancreatic tumor biology as well as to study the fate of various molecular markers during the initiation, progression, and metastasis of pancreatic neoplasia. Herein, we describe the detailed protocol for IHC analyses of pancreatic intraepithelial neoplasia in tissues and fine needle aspirates from both human and mouse samples.
Methods in molecular biology (Clifton, N.J.) 01/2013; 980:29-42.
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Sukhwinder Kaur,
Subhankar Chakraborty,
Michael J Baine,
Kavita Mallya,
Lynette M Smith,
Aaron Sasson,
Randall Brand,
Sushovan Guha,
Maneesh Jain,
Uwe Wittel,
Shailender K Singh,
Surinder K Batra
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ABSTRACT: Pancreatic cancer (PC) is lethal malignancy with very high mortality rate. Absence of sensitive and specific marker(s) is one of the major factors for poor prognosis of PC patients. In pilot studies using small set of patients, secreted acute phase proteins neutrophil gelatinase associated lipocalin (NGAL) and TGF-β family member macrophage inhibitory cytokine-1 (MIC-1) are proposed as most potential biomarkers specifically elevated in the blood of PC patients. However, their performance as diagnostic markers for PC, particularly in pre-treatment patients, remains unknown. In order to evaluate the diagnostic efficacy of NGAL and MIC-1, their levels were measured in plasma samples from patients with pre-treatment PC patients (n = 91) and compared it with those in healthy control (HC) individuals (n = 24) and patients with chronic pancreatitis (CP, n = 23). The diagnostic performance of these two proteins was further compared with that of CA19-9, a tumor marker commonly used to follow PC progression. The levels of all three biomarkers were significantly higher in PC compared to HCs. The mean (± standard deviation, SD) plasma NGAL, CA19-9 and MIC-1 levels in PC patients was 111.1 ng/mL (2.2), 219.2 U/mL (7.8) and 4.5 ng/mL (4.1), respectively. In comparing resectable PC to healthy patients, all three biomarkers were found to have comparable sensitivities (between 64%-81%) but CA19-9 and NGAL had a higher specificity (92% and 88%, respectively). For distinguishing resectable PC from CP patients, CA19-9 and MIC-1 were most specific (74% and 78% respectively). CA19-9 at an optimal cut-off of 54.1 U/ml is highly specific in differentiating resectable (stage 1/2) pancreatic cancer patients from controls in comparison to its clinical cut-off (37.1 U/ml). Notably, the addition of MIC-1 to CA19-9 significantly improved the ability to distinguish resectable PC cases from CP (p = 0.029). Overall, MIC-1 in combination with CA19-9 improved the diagnostic accuracy of differentiating PC from CP and HCs.
PLoS ONE 01/2013; 8(2):e55171. · 4.09 Impact Factor
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Satyanarayana Rachagani,
María P Torres,
Sushil Kumar,
Dhanya Haridas,
Michael Baine,
Muzafar A Macha, Sukhwinder Kaur,
Moorthy P Ponnusamy,
Parama Dey,
Parthasarathy Seshacharyulu,
Sonny L Johansson,
Maneesh Jain,
Kay-Uwe Wagner,
Surinder K Batra
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Sukhwinder Kaur,
Michael J Baine,
Sushovan Guha,
Nobuo Ochi,
Subhankar Chakraborty,
Kavita Mallya,
Colleen Thomas,
Julia Crook,
Michael B Wallace,
Timothy A Woodward,
Maneesh Jain,
Shailender Singh,
Aaron R Sasson,
Verna Skinner,
Massimo Raimondo,
Surinder K Batra
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ABSTRACT: OBJECTIVE: Pancreatic diseases pose significant diagnostic challenge as signs and symptoms often overlap. We investigated the potential of pancreatic juice neutrophil gelatinase-associated lipocalin, macrophage inhibitory cytokine 1 (MIC-1), and carbohydrate antigen 19-9 (CA19-9) to aid in the diagnosis of patients with symptoms suggestive of pancreatic diseases. METHODS: A total of 105 chronic pancreatitis (CP), pancreatic cancer (PC), and nonpancreatic nonhealthy (patients with symptoms mimicking pancreatic disease but found to be free of any pancreatic disease) patients underwent endoscopic pancreatic juice collection after secretin stimulation. Neutrophil gelatinase-associated lipocalin and MIC-1 levels were measured by enzyme-linked immunosorbent assay, whereas CA19-9 was measured by radioimmunoassay. RESULTS: Neutrophil gelatinase-associated lipocalin, MIC-1, and CA19-9 were significantly elevated in the pancreatic juice of patients with CP and patients with PC as compared with nonpancreatic nonhealthy controls (P ≤ 0.034). Neutrophil gelatinase-associated lipocalin seemed most promising in differentiating diseased versus nondiseased pancreata (areas under the curve, 0.88-0.91), whereas MIC-1 was found to be higher in patients with PC than in patients with CP (P = 0.043). Interestingly, MIC-1 levels in diabetic patients with PC were higher than in nondiabetic patients with PC (P = 0.030) and diabetic patients with CP (P = 0.087). Carbohydrate antigen 19-9 showed the least ability to distinguish patient groups (areas under the curve, 0.61-0.76). CONCLUSIONS: Pancreatic juice neutrophil gelatinase-associated lipocalin shows potential utility in establishing pancreatic etiology in the context of nonspecific symptoms, whereas MIC-1 may aid in differentiating PC from CP.
Pancreas 11/2012; · 2.39 Impact Factor
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Satyanarayana Rachagani,
María P Torres,
Sushil Kumar,
Dhanya Haridas,
Michael Baine,
Muzafar A Macha, Sukhwinder Kaur,
Moorthy P Ponnusamy,
Parama Dey,
Parthasarathy Seshacharyulu,
Sonny L Johansson,
Maneesh Jain,
Kay-Uwe Wagner,
Surinder K Batra
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ABSTRACT: BACKGROUND: Pancreatic cancer (PC) is a lethal malignancy primarily driven by activated Kras mutations and characterized by the deregulation of several genes including mucins. Previous studies on mucins have identified their significant role in both benign and malignant human diseases including PC progression and metastasis. However, the initiation of MUC expression during PC remains unknown because of lack of early stage tumor tissues from human PC patients. METHODS: In the present study, we have evaluated stage specific expression patterns of mucins during mouse PC progression in (KrasG12D;Pdx1-Cre (KC)) murine PC model from pancreatic intraepithelial neoplasia (PanIN) to pancreatic ductal adenocarcinoma (PDAC) by immunohistochemistry and quantitative real-time PCR. RESULTS: In agreement with previous studies on human PC, we observed a progressive increase in the expression of mucins particularly Muc1, Muc4 and Muc5AC in the pancreas of KC (as early as PanIN I) mice with advancement of PanIN lesions and PDAC both at mRNA and protein levels. Additionally, mucin expression correlated with the increased expression of inflammatory cytokines IFN-gamma (p < 0.0062), CXCL1 (p < 0.00014) and CXCL2 (p < 0.08) in the pancreas of KC mice, which are known to induce mucin expression. Further, we also observed progressive increase in inflammation in pancreas of KC mice from 10 to 50 weeks of age as indicated by the increase in the macrophage infiltration. Overall, this study corroborates with previous human studies that indicated the aberrant overexpression of MUC1, MUC4 and MUC5AC mucins during the progression of human PC. CONCLUSIONS: Our study reinforces the potential utility of the KC murine model for determining the functional role of mucins in PC pathogenesis by crossing KC mice with corresponding mucin knockout mice and evaluating mucin based diagnostic and therapeutic approaches for lethal PC.
Journal of Hematology & Oncology 10/2012; 5(1):68. · 3.99 Impact Factor
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ABSTRACT: Pancreatic cancer is a lethal malignancy with its incidence almost equivalent to mortality. The complex pathophysiology, absence of early diagnostic and prognostic markers and unresponsiveness to radiation and chemotherapies are major barriers against successful therapy. Poor performance of therapeutic agents, even in the initial stage of invasive cases, emphasizes the importance of early detection for improved survival. The present review discusses the challenges and advances in biomarkers including serological signatures, circulating tumor cells, autoantibodies, epigenetic markers and miRNAs that are being explored to detect this cancer at early stages. Considering the long time gap between the development of malignant lesions and full-blown primary and metastatic pancreatic cancer, unique opportunities are being contemplated for the development of potential diagnostic and prognostic markers.
Biomarkers in Medicine 10/2012; 6(5):597-612. · 0.86 Impact Factor
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ABSTRACT: MUC4 is a type-1 transmembrane mucin differentially expressed in multiple cancers and has previously been shown to potentiate progression and metastasis of pancreatic cancer. In this study, we investigated the molecular mechanisms associated with the MUC4-induced invasion and metastasis in pancreatic cancer. Stable silencing of MUC4 in multiple pancreatic cancer cells resulted in the downregulation of N-cadherin and its interacting partner fibroblast growth factor receptor 1 (FGFR1) through downregulation of partly by pFAK, pMKK7, pJNK and pc-Jun pathway and partly through PI-3K/Akt pathway. The downregulation of FGFR1 in turn led to downregulation of pAkt, pERK1/2, pNF-κB, pIkBα, uPA, MMP-9, vimentin, N-cadherin, Twist, Slug and Zeb1 and upregulation of E-cadherin, Occludin, Cytokeratin-18 and Caspase-9 in MUC4 knockdown BXPC3 and Capan1 cells compared with scramble vector transfected cells. Further, downregulation of FGFR1 was associated with a significant change in morphology and reorganization of the actin-cytoskeleton, leading to a significant decrease in motility (P < 0.00001) and invasion (P < 0.0001) in vitro and decreased tumorigenicity and incidence of metastasis in vivo upon orthotopic implantation in the athymic mice. Taken together, the results of the present study suggest that MUC4 promotes invasion and metastasis by FGFR1 stabilization through the N-cadherin upregulation.
Carcinogenesis 07/2012; 33(10):1953-64. · 5.70 Impact Factor
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ABSTRACT: Despite continuous research efforts directed at early diagnosis and treatment of pancreatic cancer (PC), the status of patients affected by this deadly malignancy remains dismal. Its notoriety with regard to lack of early diagnosis and resistance to the current chemotherapeutics is due to accumulating signaling abnormalities. Hoarding experimental and epidemiological evidences have established a direct correlation between cigarette smoking and PC risk. The cancer initiating/promoting nature of cigarette smoke can be attributed to its various constituents including nicotine, which is the major psychoactive component, and several other toxic constituents, such as nitrosamines, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, and polycyclic aromatic hydrocarbons. These predominant smoke-constituents initiate a series of oncogenic events facilitating epigenetic alterations, self-sufficiency in growth signals, evasion of apoptosis, sustained angiogenesis, and metastasis. A better understanding of the molecular mechanisms underpinning these events is crucial for the prevention and therapeutic intervention against PC. This review presents various interconnected signal transduction cascades, the smoking-mediated genotoxicity, and genetic polymorphisms influencing the susceptibility for smoking-mediated PC development by modulating pivotal biological aspects such as cell defense/tumor suppression, inflammation, DNA repair, as well as tobacco-carcinogen metabolization. Additionally, it provides a large perspective toward tumor biology and the therapeutic approaches against PC by targeting one or several steps of smoking-mediated signaling cascades.
Carcinogenesis 05/2012; 33(9):1617-28. · 5.70 Impact Factor
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ABSTRACT: Neutrophil gelatinase associated lipocalin (NGAL), also known as oncogene 24p3, uterocalin, siderocalin or lipocalin 2, is a 24kDa secreted glycoprotein originally purified from a culture of mouse kidney cells infected with simian virus 40 (SV-40). Subsequent investigations have revealed that it is a member of the lipocalin family of proteins that transport small, hydrophobic ligands. Since then, NGAL expression has been reported in several normal tissues where it serves to provide protection against bacterial infection and modulate oxidative stress. Its expression is also dysregulated in several benign and malignant diseases. Its small size, secreted nature and relative stability have led to it being investigated as a diagnostic and prognostic biomarker in numerous diseases including inflammation and cancer. Functional studies, conducted primarily on lipocalin 2 (Lcn2), the mouse homologue of human NGAL have revealed that Lcn2 has a strong affinity for iron complexed to both bacterial siderophores (iron-binding proteins) and certain human proteins like norepinephrine. By sequestering iron-laden siderophores, Lcn2 deprives bacteria of a vital nutrient and thus inhibits their growth (bacteriostatic effect). In malignant cells, its proposed functions range from inhibiting apoptosis (in thyroid cancer cells), invasion and angiogenesis (in pancreatic cancer) to increasing proliferation and metastasis (in breast and colon cancer). Ectopic expression of Lcn2 also promotes BCR-ABL induced chronic myelogenous leukemia in murine models. By transporting iron into and out of the cell, NGAL also regulates iron responsive genes. Further, it stabilizes the proteolytic enzyme matrix metalloprotease-9 (MMP-9) by forming a complex with it, and thereby prevents its autodegradation. The factors regulating NGAL expression are numerous and range from pro-inflammatory cytokines like interleukins, tumor necrosis factor-α and interferons to vitamins like retinoic acid. The purpose of this review article is to examine the expression, structure, regulation and biological role of NGAL and critically assess its potential as a novel diagnostic and prognostic marker in both benign and malignant human diseases.
Biochimica et Biophysica Acta 03/2012; 1826(1):129-69. · 4.66 Impact Factor
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ABSTRACT: Antibodies, with their unmatched ability for selective binding to any target, are considered as potentially the most specific probes for imaging. Their clinical utility, however, has been limited chiefly due to their slow clearance from the circulation, longer retention in non-targeted tissues and the extensive optimization required for each antibody-tracer. The development of newer contrast agents, combined with improved conjugation strategies and novel engineered forms of antibodies (diabodies, minibodies, single chain variable fragments, and nanobodies), have triggered a new wave of antibody-based imaging approaches. Apart from their conventional use with nuclear imaging probes, antibodies and their modified forms are increasingly being employed with non-radioisotopic contrast agents (MRI and ultrasound) as well as newer imaging modalities, such as quantum dots, near infra red (NIR) probes, nanoshells and surface enhanced Raman spectroscopy (SERS). The review article discusses new developments in the usage of antibodies and their modified forms in conjunction with probes of various imaging modalities such as nuclear imaging, optical imaging, ultrasound, MRI, SERS and nanoshells in preclinical and clinical studies on the diagnosis, prognosis and therapeutic responses of cancer.
Cancer letters 10/2011; 315(2):97-111. · 4.86 Impact Factor
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10/2011; , ISBN: 978-953-307-252-4
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ABSTRACT: Pancreatic cancer (PC) is one of the most lethal malignancies. It has a 5-year survival rate of only 6%, owing in part to the lack of a reliable tumor marker for early diagnosis. Recent research has shown that the mucin protein MUC4 is aberrantly expressed in pancreatic adenocarcinoma cell lines and tissues but is undetectable in normal pancreas and chronic pancreatitis. Thus, the level of MUC4 in patient sera has the potential to function as a diagnostic and prognostic marker for PC. However, the measurement of MUC4 in sera using conventional test platforms (e.g., enzyme linked immunosorbent assay (ELISA) and radioimmunoassay (RIA)) has been unsuccessful. This has prevented the assessment of the utility of this protein as a possible PC marker in sera. In addressing this obstacle, the work herein examines the potential to create a simple diagnostic test for MUC4 through the development of a surface-enhanced Raman scattering (SERS)-based immunoassay, which was then used to demonstrate the first ever detection of MUC4 in cancer patient serum samples. Importantly, these measurements showed that sera from patients with PC produced a significantly higher SERS response for MUC4 compared to sera from healthy individuals and from patients with benign diseases. These results indicate that a SERS-based immunoassay can monitor MUC4 levels in patient sera, representing a much needed first step toward assessing the potential of this protein to serve as a serum marker for the early stage diagnosis of PC. This paper details these and other findings (i.e., the detection of the mucin protein CA19-9), which demonstrate that our SERS assay outperforms conventional assays (i.e., RIA and ELISA) with respect to limits of detection, readout time, and required sample volume.
Analytical Chemistry 03/2011; 83(7):2554-61. · 5.86 Impact Factor
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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.
PLoS ONE 01/2011; 6(8):e23344. · 4.09 Impact Factor
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ABSTRACT: We sought to validate global microarray results indicating the differential expression of 383 genes in Peripheral Blood Mononuclear Cells (PBMCs) from patients with pancreatic cancer (PC) and to further evaluate their PC diagnostic potential.
In total, 177 patients were recruited (47 healthy controls (HC), 35 chronic pancreatitis (CP) patients, and 95 PC patients). PBMC expressions of six genes from our previous study (ANXA3, ARG1, CA5B, F5, SSBP2, and TBC1D8) along with four new genes (MIC1, NGAL, MUC1, and MUC16) were analyzed using multiplex Q-RT PCR.
Differential expressions of 5 of the 6 genes previously identified by PBMC microarray were validated in this study. Multivariate models for PBMC gene expression were attempted to determine if any combination was diagnostically superior to CA19-9 alone. We found that addition of PBMC CA5B, F5, SSBP2, and MIC1 expression levels to CA19-9 significantly improved CA19-9's diagnostic abilities when comparing resectable PC to CP patients (p=0.023).
Results of our previous study were validated, indicating reproducibility of PC-associated PBMC expression profiling. We identified a score-based model that can differentiate resectable PC from CP better than CA19-9, potentiating that PBMC differential expression analysis may offer a novel tool for early PC diagnosis.
Cancer biomarkers: section A of Disease markers 01/2011; 11(1):1-14. · 1.08 Impact Factor
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ABSTRACT: BACKGROUND:: The authors previously reported that neutrophil gelatinase-associated lipocalin (NGAL) overexpression significantly blocked invasion and angiogenesis of pancreatic ductal adenocarcinoma (PDAC). They also demonstrated a loss of NGAL expression in the advanced stages of PDAC. However, little is known regarding the mechanisms of NGAL regulation in PDAC. Because the epidermal growth factor (EGF)-EGF receptor (EGFR) axis is up-regulated significantly in PDAC, they examined EGF-mediated NGAL regulation in these cells. METHODS:: The NGAL-positive cell lines AsPC-1 and BxPC-3 were used as a model system. Quantitative real-time polymerase chain reaction (RT-PCR), Western blot analysis, and immunofluorescence studies were used to investigate EGF-mediated effects on NGAL expression. E-cadherin expression was manipulated using lentiviral overexpression or small hairpin RNA constructs. NGAL promoter activity was assessed by luciferase-reporter assay and electrophoretic mobility shift assay. RESULTS:: NGAL expression was positively associated with tumor differentiation and was down-regulated significantly after EGF treatment along with a concomitant reduction of E-cadherin expression in PDAC cells. E-cadherin down-regulation was partly through the EGFR-dependent mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) (MEK-ERK) signaling pathway. In addition, E-cadherin down-regulation reduced NGAL expression in PDAC cells, whereas overexpression of E-cadherin led to increased NGAL expression and partly rescued the inhibition of NGAL expression by EGF. Furthermore, EGF, in part through E-cadherin, reduced NGAL promoter activity by blocking nuclear factor κB (NF-κB) activation. CONCLUSIONS:: The current study demonstrated for the first time that EGF potently blocked NGAL expression in PDAC cells. This effect was mediated in part through activation of the EGFR-MEK-ERK signaling pathway, which, in turn, down-regulated E-cadherin with a subsequent reduction in NF-κB activation. These findings illustrate a novel mechanism by which EGF regulates NGAL expression in PDAC. Cancer 2011;. © 2010 American Cancer Society.
Cancer 12/2010; · 4.77 Impact Factor
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ABSTRACT: To determine the cellular location and expression of MUC17 mucin in specimens of normal, inflamed and neoplastic colon.
Immunohistochemical analysis of human surgical resection specimens (n=106) was performed with a specific antibody to the MUC17 apomucin protein. A semi-quantitative scoring system was used to measure MUC17 expression. In various colon cancer cell lines, the MUC17 expression was examined by immunoblot analysis and normal RT-PCR.
MUC17 was highly expressed on the surface epithelium and crypts of colonic mucosa. In contrast, the expression of MUC17 was significantly decreased in colonic mucosa of chronic ulcerative colitis (p<0.0001) and ischaemic colitis (p=0.003). Similarly, MUC17 expression was decreased in hyperplastic polyps (p=0.0003), tubular and tubulovillous adenomas (p<0.0001) and colon cancers (p<0.0001). Furthermore, of eight different colon cancer cell lines, MUC17 expression was only detected in LS174T and LS180 cells.
Results indicate that the potential protective effects of this membrane-bound mucin are primarily or secondarily diminished in inflammatory and neoplastic conditions. Further research is needed to determine the specific role of MUC17 in the pathogenesis of these conditions.
Journal of clinical pathology 08/2010; 63(8):702-7. · 2.43 Impact Factor
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ABSTRACT: About 210,000 new cases of acute pancreatitis (AP) involving reversible inflammation of the pancreas are reported in the United States every year. About one-fourth of all patients with AP go on to develop severe acute pancreatitis (SAP), which, unlike uncomplicated or mild acute pancreatitis (MAP, usually a self-limiting disease), constitutes a life-threatening condition with systemic complications, chiefly multiorgan dysfunction. An early prediction of the severity and outcome of patients with acute pancreatitis (AP) can lead to better treatment regimens for patients with SAP. There is currently no established biomarker for the early diagnosis of SAP. In this study, we investigated the potential of serum neutrophil gelatinase-associated lipocalin (NGAL) as an early marker to distinguish severe (SAP) from MAP and examine its ability to predict the prognosis of patients with SAP.
To check the time kinetics of rise in NGAL during AP, we quantified NGAL levels in sera from mice with MAP or SAP at various time points (6, 12, 24 and 48 h) using sandwich enzyme-linked immunosorbent assay. NGAL levels were also quantified in serum from 28 MAP and 16 SAP cases and compared with 28 chronic pancreatitis and 30 healthy control samples. Samples collected within 5 days from onset of symptoms were included. The relationship of NGAL levels with survival and multiorgan failure (MOF) in SAP was also examined.
Although NGAL levels were significantly higher in mice with both MAP and SAP 6 h after induction (compared to control animals), only mice with SAP exhibited a significant increase in NGAL levels at 24 h (P=0.003). NGAL levels declined at 48 h after induction in animals with both MAP and SAP but did not reach baseline levels. Among patients, mean (+/-s.e.) serum NGAL level was significantly higher in SAP (634+/-139 ng/ml) compared to MAP (84.7+/-7 ng/ml, P=0.0001). On subanalysis, the difference between MAP and SAP cases was significant in the first 48 h but not at 72, 96, or 120 h. NGAL was 100%, 96%, 97%, and 84% specific and 100%, 87.5%, 92%, and 94% sensitive in distinguishing SAP from MAP at 48, 72, 96, and 120 h, respectively, after the onset of symptoms. NGAL levels were significantly higher in SAP cases complicated by MOF (P=0.004), and high NGAL levels in SAP appeared to correlate with a fatal outcome.
Our data provide the first evidence for the potential of serum NGAL as an early marker to distinguish MAP from SAP. Further, high NGAL levels predict MOF and fatal outcome in patients with SAP. This study provides sufficient evidence for multi-institutional randomized trials for estimating the potential of NGAL as early biomarker for SAP.
The American Journal of Gastroenterology 02/2010; 105(9):2050-9. · 7.28 Impact Factor
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ABSTRACT: Malaria parasite secretes various proteins in infected RBC for its growth and survival. Thus identification of these secretory proteins is important for developing vaccine/drug against malaria. The existing motif-based methods have got limited success due to lack of universal motif in all secretory proteins of malaria parasite.
In this study a systematic attempt has been made to develop a general method for predicting secretory proteins of malaria parasite. All models were trained and tested on a non-redundant dataset of 252 secretory and 252 non-secretory proteins. We developed SVM models and achieved maximum MCC 0.72 with 85.65% accuracy and MCC 0.74 with 86.45% accuracy using amino acid and dipeptide composition respectively. SVM models were developed using split-amino acid and split-dipeptide composition and achieved maximum MCC 0.74 with 86.40% accuracy and MCC 0.77 with accuracy 88.22% respectively. In this study, for the first time PSSM profiles obtained from PSI-BLAST, have been used for predicting secretory proteins. We achieved maximum MCC 0.86 with 92.66% accuracy using PSSM based SVM model. All models developed in this study were evaluated using 5-fold cross-validation technique.
This study demonstrates that secretory proteins have different residue composition than non-secretory proteins. Thus, it is possible to predict secretory proteins from its residue composition-using machine learning technique. The multiple sequence alignment provides more information than sequence itself. Thus performance of method based on PSSM profile is more accurate than method based on sequence composition. A web server PSEApred has been developed for predicting secretory proteins of malaria parasites,the URL can be found in the Availability and requirements section.
BMC Bioinformatics 02/2008; 9:201. · 2.75 Impact Factor
