Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:O76050 (neu)
 3,969 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Not uncommonly, bile duct adenomas (BDAs) and hamartomas (BDHs) of the liver may be difficult to distinguish from metastatic well-differentiated ductal adenocarcinoma of the pancreas. However, this distinction is critical for proper staging and patient management. The primary purpose of this study was to determine if a panel of immunohistochemical stains can help distinguish BDA or BDH from metastatic pancreatic adenocarcinoma in the liver. Routinely processed tissue sections from 25 BDA, 10 BDH, 25 metastatic pancreatic adenocarcinomas to the liver and 6 cases each of metastatic colorectal, breast, and lung adenocarcinomas were immunohistochemically stained for CK7, CK8/CK18, CK19, CK20, p53, p63, TAG-72, monoclonal CEA (mCEA), polyclonal CEA (pCEA), HER-2/neu, AMACR (alpha-methylacyl-CoA racemase), Dpc4 (Smad4), and mesothelin. The slides were evaluated in a blinded fashion, and the results were compared between the benign and malignant lesions. Significantly more (P < 0.05) metastatic pancreatic adenocarcinomas were positive for CK20 (76%), p53 (60%), TAG-72 (88%), mCEA (92%), HER2/neu (40%), and mesothelin (64%) and showed loss of Dpc4 (44%), in comparison to BDA (CK20, 40%; p53, 0%; TAG-72, 0%; mCEA, 0%; HER2/neu, 12%; mesothelin, 0%; loss of Dpc4, 0%) or BDH (CK20, 10%; p53, 0%; TAG-72, 0%; mCEA, 10%; HER2/neu, 0%; mesothelin, 0%; loss of Dpc4, 0%). Of these antibodies, p53, TAG-72, mCEA, loss of Dpc4, and mesothelin had the highest specificity for pancreatic adenocarcinoma, with mCEA having the highest sensitivity (92%). No significant differences were observed in the degree of CK7, CK8/CK18, CK19, or pCEA expression between the three types of lesions. Although none of the BDA or BDH was positive for either p63 or AMACR, two of the metastatic pancreatic adenocarcinomas (8%) were positive for each of these peptides (P > 0.05). For nonpancreatic adenocarcinomas, mCEA showed a reasonably high sensitivity and 100% specificity in the differential diagnosis versus BDA. Immunohistochemical expression of p53, TAG-72, mCEA, mesothelin, and loss of Dpc4 can help distinguish metastatic pancreatic adenocarcinoma in the liver from BDA or BDH. Although p63 and AMACR are also specific for pancreatic adenocarcinoma, their low sensitivity limits their use in clinical practice.
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PMID:Immunohistochemistry can help distinguish metastatic pancreatic adenocarcinomas from bile duct adenomas and hamartomas of the liver. 1572 8

Tumor microenvironments present significant barriers to penetration by antibodies, immunoconjugates, and other immunotoxins. In this report, we illustrate a novel strategy to increase tumor cell uptake of immunotoxin by combination with Taxol. SS1P is an immunotoxin composed of the Fv portion of a mesothelin-specific antibody fused to a bacterial toxin that is presently undergoing phase II testing in mesothelioma. Using novel flow cytometry and gel filtration methods, we quantified SS1P uptake in individual tumor cells along with levels of shed mesothelin (sMSLN), a barrier of SS1P therapy. The validity of our flow cytometric method was confirmed by the ability to similarly quantitate tumor cell uptake of Herceptin and an immunotoxin targeting HER2/neu. SS1P uptake peaked several hours after SS1P was cleared from the blood, reflecting an intratumor distribution process of SS1P that is independent of blood supply. Using the methods developed, we demonstrated that Taxol could improve SS1P penetration into tumors in parallel with an associated reduction of sMSLN in tumor extracellular fluid. Our findings offer a mechanistic rationale to combine SS1P with Taxol or another cytotoxic drug as a strategy to increase immunotoxin uptake by tumor cells. Further, we suggest one basis to understand why chemotherapy and antibody-based therapies cooperate when combined in cancer treatment.
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PMID:A flow cytometry method to quantitate internalized immunotoxins shows that taxol synergistically increases cellular immunotoxins uptake. 2010 26

Mesothelin is a cell-surface glycoprotein present on mesothelial cells and elicits T cell responses in a variety of cancers including pancreatic, biliary and ovarian cancer. Breast cancer is not known to express mesothelin. We postulated that mesothelin may be a unique tumor-associated antigen in triple negative breast cancer (TNBC), a less common breast cancer subtype which may have been under-represented in prior studies that characterized mesothelin expression. Therefore, we screened 99 primary breast cancer samples by immunohistochemistry analysis using formalin-fixed paraffin-embedded archival tumor tissues and confirmed that mesothelin was overexpressed in the majority of TNBC (67 %) but only rarely in <5 % ER(+) or Her2-neu(+) breast cancer, respectively. To determine whether mesothelin may be exploited as a novel immunotherapy target in breast cancer, an in vitro cell killing assay was performed to compare the ability of genetically modified T cells expressing a chimeric antibody receptor (CAR) specific for mesothelin (mesoCAR T cells) or non-transduced T cells to kill mesothelin-expressing primary breast cancer cells. A significantly higher anti-tumor cytotoxicity by mesoCAR T cells was observed (31.7 vs. 8.7 %, p < 0.001). Our results suggest that mesothelin has promise as a novel immunotherapy target for TNBC for which effective targeted therapy is lacking to date.
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PMID:Mesothelin, a novel immunotherapy target for triple negative breast cancer. 2241 2

The identification of new therapeutic targets is of profound importance if we are to improve outcomes in gastroesophageal cancer. This study assessed the rate of mesothelin expression in tumors of western patients with upper gastrointestinal tract carcinomas. In addition, the AGS gastric cancer cell line was tested for sensitivity to SS1(dsFv)PE38, a mesothelin-targeting immunotoxin. Previously constructed tissue microarrays containing samples from 127 patients with gastroesophageal adenocarcinomas were examined by immunohistochemistry (IHC) for mesothelin expression. Labeling for HER2-neu, E-cadherin, and c-met were also assessed. Tumors were considered positive for mesothelin if at least moderate cytoplasmic/membranous or luminal staining was present in minimum 10% of the neoplastic cells. The AGS gastric cancer cell line was assessed for surface mesothelin expression by flow cytometry and the viability of cells treated with SS1P was measured. Gastroesophageal cancers were mesothelin positive in 64 of 127 tumors [50.4%; 95% confidence interval (CI), 41.4%-59.4%], whereas only 9 carcinomas (7.1%; 95% CI, 3.3%-13.0%) were HER2-neu IHC 3+ positive and 8 (6.6%; 95% CI, 2.9%-12.5%) were c-met positive. Mesothelin expression increased from stage I to stage IV tumors (37.5% to 56.3%, respectively, P=0.10). The AGS gastric cancer cell line was sensitive to the immunotoxin with an EC50 value in the low picomolar range (0.4 ng/mL). A gastric cancer cell line derived from a western patient was exquisitely sensitive to the mesothelin-targeted immunotoxin SS1P. Clinical trials involving novel mesothelin targeted immunotherapeutics in gastroesophageal cancer are currently in development.
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PMID:Mesothelin Expression in Advanced Gastroesophageal Cancer Represents a Novel Target for Immunotherapy. 2689 50