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New Philadelphia, PA, United States

Valsecchi M.E.,Thomas Jefferson University | McDonald M.,Thomas Jefferson University | Brody J.R.,Thomas Jefferson University | Hyslop T.,Thomas Jefferson University | And 6 more authors.
Cancer | Year: 2012

BACKGROUND: The aim of this study was to evaluate the expression of epidermal growth factor receptor (EGFR) and insulinlike growth factor 1 receptor (IGF-1R) proteins and IGF-1R gene copy numbers in pancreatic ductal adenocarcinoma in relation to patients' characteristics and prognosis. METHODS: Immunohistochemical staining was performed on formalin-fixed paraffin-embedded tissue derived from tumor specimens recovered during surgery. Slides were evaluated for membranous EGFR and IGF-1R staining using both the HercepTest and the semiquantitative H-score systems. Chromogenic in situ hybridization was performed to quantify IGF-1R gene copy number. The primary outcome was the association between EGFR expression, IGF-1R expression-in both neoplastic epithelial and stromal cells-or IGF-1R gene copy number and overall survival. Secondary outcomes included associations between EFGR and IGF-1R expression and pathologic variables. RESULTS: A total of 105 patients were included. EGFR expression was present in 30.4% of cases and was associated with lymph node metastasis (P =.038). IGF-1R was overexpressed in 53% of tumors and correlated with higher tumor grade (P =.033). High membranous expression of EGFR (P <.001) and/or IGF-1R (P =.004), the cytoplasmic detection of EGFR (P =.027), and high expression levels of IGF-1R in the tumoral stroma (P <.001) were all associated with shorter overall survival, being significantly better in patients who simultaneously do not express membranous EGFR or stromal IGF-1R. CONCLUSIONS: EGFR and IGF-1R expression, in neoplastic and stromal cells, seems to be an important prognostic factor. © 2011 American Cancer Society. Source

Burkhart R.A.,Biliary and Related Cancer Center | Pineda D.M.,Biliary and Related Cancer Center | Chand S.N.,Biliary and Related Cancer Center | Romeo C.,Biliary and Related Cancer Center | And 7 more authors.
RNA Biology | Year: 2013

Cancer cell metabolism differs from normal cells, yet the regulatory mechanisms responsible for these differences are incompletely understood, particularly in response to acute changes in the tumor microenvironment. HuR, an RNAbinding protein, acts under acute stress to regulate core signaling pathways in cancer through post-transcriptional regulation of mRNA targets. We demonstrate that HuR regulates the metabolic phenotype in pancreatic cancer cells and is critical for survival under acute glucose deprivation. Using three pancreatic cancer cell line models, HuR-proficient cells demonstrated superior survival under glucose deprivation when compared with isogenic cells with siRNA-silencing of HuR expression (HuR-deficient cells). We found that HuR-proficient cells utilized less glucose, but produced greater lactate, as compared with HuR-deficient cells. Acute glucose deprivation was found to act as a potent stimulus for HuR translocation from the nucleus to the cytoplasm, where HuR stabilizes its mRNA targets. We performed a gene expression array on ribonucleoprotein immunoprecipitated mRNAs bound to HuR and identified 11 novel HuR target transcripts that encode enzymes central to glucose metabolism. Three (GPI, PRPS2 and IDH1) were selected for validation studies, and confirmed as bona fide HuR targets. These findings establish HuR as a critical regulator of pancreatic cancer cell metabolism and survival under acute glucose deprivation. Further explorations into HuR's role in cancer cell metabolism should uncover novel therapeutic targets that are critical for cancer cell survival in a metabolically compromised tumor microenvironment. © 2013 Landes Bioscience. Source

Lazar M.,Biliary and Related Cancer Center | Sullivan J.,Biliary and Related Cancer Center | Chipitsyna G.,Biliary and Related Cancer Center | Aziz T.,Biliary and Related Cancer Center | And 7 more authors.
Surgery | Year: 2010

Background: Cigarette smoke and nicotine are among the leading environmental risk factors for developing pancreatic ductal adenocarcinoma (PDA). We showed recently that nicotine induces osteopontin (OPN), a protein that plays critical roles in inflammation and tumor metastasis. We identified an OPN isoform, OPNc, that is selectively inducible by nicotine and highly expressed in PDA tissue from smokers. In this study, we explored the potential proinflammatory role of nicotine in PDA through studying its effect on the expression of monocyte chemoattractant protein (MCP)-1 and evaluated the role of OPN in mediating these effects. Methods: MCP-1 mRNA and protein in PDA cells treated with or without nicotine (3-300 nmol/L) or OPN (0.15-15 nmol/L) were analyzed by real-time polymerase chain reaction and enzyme-linked immunosorbent assay. Luciferase-labeled promoter studies evaluated the effects of nicotine and OPN on MCP-1 transcription. Intracellular and tissue colocalization of OPN and MCP-1 were examined by immunofluorescence and immunohistochemistry. Results: Nicotine treatment significantly increased MCP-1 expression in PDA cells. Interestingly, blocking OPN with siRNA or OPN antibody abolished these effects. Transient transfection of the OPNc gene in PDA cells or their treatment with recombinant OPN protein significantly (P < .05) increased MCP-1 mRNA and protein and induced its promoter activity. MCP-1 was found in 60% of invasive PDA lesions, of whom 66% were smokers. MCP-1 colocalized with OPN in PDA cells and in the malignant ducts, and correlated well with higher expression levels of OPN in the tissue from patients with invasive PDA. Conclusion: Our data suggest that cigarette smoking and nicotine may contribute to PDA inflammation by inducing MCP-1 and provide a novel insight into a unique role for OPN in mediating these effects. © 2010 Mosby, Inc. Source

Rittenhouse D.W.,Thomas Jefferson University | Talbott V.A.,Thomas Jefferson University | Anklesaria Z.,Thomas Jefferson University | Brody J.R.,Thomas Jefferson University | And 5 more authors.
Journal of Gastrointestinal Surgery | Year: 2011

Background: Cystic fibrosis (CF) is the most commonly inherited lethal autosomal recessive genetic disease amongst Caucasians. CF results from mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Patients with homozygous or compound heterozygous CFTR mutations have a risk of pancreatitis, but typically do not live long enough to develop pancreatic ductal adenocarcinoma (PDA), a disease that has an average age at diagnosis of 65 years. Little is known about the risk of the development of PDA in people who are heterozygous for mutations in the CFTR gene. Patients and Methods: We report a case of a patient with PDA who underwent resection, who is a carrier for the W1282X nonsense mutation in the CFTR gene. The patient is of Ashkenazi Jewish ethnicity and has a family history of CF, but no family history of PDA. We reviewed the English language literature for the prevalence of PDA in CF patients (and CFTR mutations in the setting of PDA) and their significance in terms of screening, and the use of this mutation as a biomarker for an increased risk of the development of PDA. Conclusion: We conclude that patients with CFTR mutations, who also have other risks for the development of PDA such as a family history of the disease, should undergo screening and be educated about their risks. © 2011 The Society for Surgery of the Alimentary Tract. Source

Burkhart R.A.,Biliary and Related Cancer Center | Peng Y.,University of Delaware | Norris Z.A.,Biliary and Related Cancer Center | Tholey R.M.,Biliary and Related Cancer Center | And 19 more authors.
Molecular Cancer Research | Year: 2013

Pancreatic ductal adenocarcinoma (PDA) is the fourth leading cause of cancer-related death in the United States, with a 95% five-year mortality rate. For over a decade, gemcitabine (GEM) has been the established first-line treatment for this disease despite suboptimal response rates. The development of PARP inhibitors that target the DNA damage repair (DDR) system in PDA cells has generated encouraging results. Ubiquitinspecific peptidase 11 (USP11), an enzyme that interacts with the DDR protein BRCA2, was recently discovered to play a key role in DNA double-strand break repair and may be a novel therapeutic target. A systematic high-throughput approach was used to biochemically screen 2,000 U.S. Food and Drug Administration (FDA)-approved compounds for inhibition of USP11 enzymatic activity. Six pharmacologically active small molecules that inhibit USP11 enzymatic activity were identified. An in vitro drug sensitivity assay demonstrated that one of these USP11 inhibitors, mitoxantrone, impacted PDA cell survival with an IC50 of less than 10 nM. Importantly, across six different PDA cell lines, two with defects in the Fanconi anemia/ BRCA2 pathway (Hs766T and Capan-1), mitoxantrone is 40- to 20,000-fold more potent than GEM, with increased endogenous USP11 mRNA levels associated with increased sensitivity to mitoxantrone. Interestingly, USP11 silencing in PDA cells also enhanced sensitivity to GEM. These findings establish a preclinical model for the rapid discovery of FDA-approved compounds and identify USP11 as a target of mitoxantrone in PDA. Implications: This high-throughput approach provides a strong rationale to study mitoxantrone in an early-phase clinical setting for the treatment of PDA. © 2013 AACR. Source

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