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1.
Adv Exp Med Biol ; 1290: 51-65, 2021.
Article in English | MEDLINE | ID: mdl-33559854

ABSTRACT

Unlike other malignancies, ovarian cancer (OC) creates a complex tumor microenvironment with distinctive peritoneal ascites consisting of a mixture of several immunosuppressive cells which impair the ability of the patient's immune system to fight the disease. The poor survival rates observed in advanced stage OC patients and the lack of effective conventional therapeutic options have been attributed in large part to the immature dendritic cells (DCs), IL-10 secreting regulatory T cells, tumor-associated macrophages, myeloid-derived suppressor cells, and cancer stem cells that secrete inhibitory cytokines. This review highlights the critical role played by the intraperitoneal presence of IL-10 in the generation of an immunosuppressive tumor microenvironment. Further, the effect of antibody neutralization of IL-10 on the efficacy of DC and chimeric antigen receptor T-cell vaccines will be discussed. Moreover, we will review the influence of IL-10 in the promotion of cancer stemness in concert with the NF-κB signaling pathway with regard to OC progression. Finally, understanding the role of IL-10 and its crosstalk with various cells in the ascitic fluid may contribute to the development of novel immunotherapeutic approaches with the potential to kill drug-resistant OC cells while minimizing toxic side effects.


Subject(s)
Interleukin-10 , Ovarian Neoplasms , Carcinoma, Ovarian Epithelial , Dendritic Cells , Female , Humans , Ovarian Neoplasms/therapy , Signal Transduction , Tumor Microenvironment
2.
Surgery ; 166(4): 503-508, 2019 10.
Article in English | MEDLINE | ID: mdl-31416604

ABSTRACT

BACKGROUND: We have previously demonstrated in vitro cytotoxicity of mesothelin-chimeric antigen receptor autologous T cells against pancreatic cancer cells using lentiviral vectors, but these vectors pose safety concerns. Here, we incorporated Sleeping Beauty and minicircle design enhancements into interleukin-2-secreting natural NK-92MI cells to eliminate both bacterial and viral components and address inhibition by the tumor microenvironment. METHODS: Parental (conventional deoxyribonucleic acid)-mesothelin-chimeric antigen receptor and minicircle-mesothelin-chimeric antigen receptor vectors were electroporated into NK-92MI cells and engraftment was visualized by immunofluorescence analysis with protein-L staining. Interferon-γ and granzyme B secretion were measured by enzyme-linked immunosorbent assay from cocultures of parental-mesothelin-chimeric antigen receptors and minicircle-mesothelin-chimeric antigen receptors with human pancreatic cancer cells, and cytotoxicity of chimeric antigen receptor NK-92MI cells was tested against three pancreatic cancer cell lines. RESULTS: Cloning of mesothelin-chimeric antigen receptor Sleeping Beauty into a minicircle vector removed its bacterial backbone and reduced its size with improved electroporation efficiency. Chimeric antigen receptor engraftment, Interferon-γ and granzyme B secretion, and specific lysis against all three pancreatic cancer lines were significantly increased with minicircle-mesothelin-chimeric antigen receptor versus parental-mesothelin-chimeric antigen receptor NK-92MI cells. CONCLUSION: We provide proof of concept that allogeneic mesothelin-chimeric antigen receptor NK-92MI cells with hybrid Sleeping Beauty and minicircle technologies provide increased engraftment and cytotoxicity in vitro with potential safety benefits when translated to the clinical arena.


Subject(s)
Cell Death/immunology , GPI-Linked Proteins/pharmacology , Immunotherapy, Adoptive/methods , Killer Cells, Natural/immunology , Pancreatic Neoplasms/pathology , Receptors, Chimeric Antigen/immunology , Cell Line, Tumor , Electroporation/methods , Enzyme-Linked Immunosorbent Assay , Humans , In Vitro Techniques , Killer Cells, Natural/drug effects , Mesothelin , Pancreatic Neoplasms/therapy , Sensitivity and Specificity , Tumor Microenvironment
3.
J Surg Oncol ; 119(7): 979-986, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30729542

ABSTRACT

BACKGROUND AND OBJECTIVES: This study is a systematic review with meta-analysis designed to compare the perioperative and oncological outcomes of the abdominoperineal resection (APR) carried out in the prone jack-knife position (P-APR) vs the classic lithotomy position (C-APR). METHODS: We conducted an electronic search through PubMed utilizing the PRISMA guidelines. We included all randomized and nonrandomized studies which allowed for comparative analysis between the two groups. Research that focused on and analyzed the extralevator abdominal excision were excluded. Pooled variables and number of events were analyzed using the random-effect model. RESULTS: The final analysis included seven nonrandomized retrospective cohorts encompassing 1663 patients. P-APR was associated with decreased operative time (OT) (DM, -43.8 minutes; P < 0.01) and estimated blood loss (EBL) (DM, 86.9 mL; P < 0.01). There were no observed differences regarding perineal wound infections (PWI) (odds ratio [OR], 0.36; P = 0.18), intraoperative perforation of rectum (IOP) (OR, 0.98; P = 0.97), circumferential resection margin (CRM) positivity (OR, 1.02; P = 0.98) or 5-year LR (OR, 1.00; P = 0.99). CONCLUSION: The prone approach for APR is associated with decreased EBL and OT, although not with any change in the incidence of PWI or IOP. Moreover, surgical positioning per se does not appear to affect the CRM positivity rates or LR rate.


Subject(s)
Patient Positioning/methods , Proctectomy/methods , Rectal Neoplasms/surgery , Humans , Margins of Excision , Prone Position , Randomized Controlled Trials as Topic , Retrospective Studies , Treatment Outcome
4.
Surgery ; 163(3): 627-632, 2018 03.
Article in English | MEDLINE | ID: mdl-29336814

ABSTRACT

BACKGROUND: Pancreatic cancer cells are known to shield themselves from immunosurveillance by secreting immune inhibitory cytokines such as Interleukin-10. Using mesothelin, a differentiating antigen that is overexpressed in pancreatic cancer, we assessed the negative effect of the tumor microenvironment on chimeric antigen receptor T cell-based immunotherapy and its reversal via depletion of Interleukin-10. METHODS: T cells cultured in pancreatic cancer-cell-conditioned medium were transduced with lentiviruses encoding mesothelin-chimeric antigen receptor in the presence or absence of anti-Interleukin-10-blocking antibody. RESULTS: Coculture supernatants of conditioned medium displayed significant inhibition of interferon γ and granzyme B secretion, both of which are crucial for induction of target cell cytotoxicity. In contrast, this inhibition was restored toward baseline when conditioned medium was Interleukin-10- depleted (p < .05 for both interferon γ and granzyme B). In addition, we observed a significant decrease in mesothelin-chimeric antigen receptor T cell-induced cytotoxicity of BxPC-3 target cells in the presence of conditioned medium. Furthermore, we observed a partial blunting of this inhibition when Interleukin-10 was depleted from the conditioned medium. CONCLUSION: Substantial reversal of tumor-derived immunosuppression may be achieved by blocking Interleukin-10 in the local microenvironment, allowing for more effective cytotoxicity of mesothelin-engrafted chimeric antigen receptor T cells and enhancing the potential for clinical application.


Subject(s)
GPI-Linked Proteins/pharmacology , Interleukin-10/physiology , Pancreatic Neoplasms/pathology , T-Lymphocytes/physiology , Tumor Microenvironment/physiology , Cell Culture Techniques , Cell Line, Tumor , Humans , Immunotherapy , Mesothelin , Receptors, Antigen, T-Cell
6.
Surgery ; 158(4): 981-6; discussion 986-7, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26189069

ABSTRACT

PURPOSE: MicroRNA (miR)-26a has been identified as a tumor suppressor in pancreatic cancer cells. Although wild-type p53 controls cell-cycle progression, its mutant form normally present in pancreatic cancer loses this capability. Phosphorylation is known to restore wild-type activity to mutant p53. We, therefore, examined whether miR-26a treatment can restore wild-type functions of mutant p53 via phosphorylation, resulting in inhibition of cell growth. METHODS: The human pancreatic cancer cell line BxPc-3 harboring mutant p53 was used for colony formation, cell-cycle, and Western blotting assays. Gene profile analysis was conducted after transfection with pre-miR-26a. RESULTS: miR-26a expression significantly decreased cell proliferation by 80% along with marked inhibition of colony formation and cell migration. Cell-cycle inhibition at the G0/G1 interface was observed along with enhanced drug retention and increased chemosensitivity to gemcitabine. Mutant p53 was phosphorylated rapidly at its Ser9 and Ser392 residues, but not at Ser15 or Ser20. Gene profile analysis of pre-miR-26a-transfected cells showed a significant increase in gene transcripts promoting apoptosis and p53 activation, with decreased levels of genes involved in cell-cycle progression. CONCLUSION: Delivery of miR-26a may represent a novel strategy for inhibiting pancreatic cancer growth, at least in part by enhancing phosphorylation of mutant p53 to restore its wild-type functions.


Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma, Pancreatic Ductal/metabolism , Cell Proliferation/physiology , MicroRNAs/metabolism , Pancreatic Neoplasms/metabolism , Tumor Suppressor Protein p53/metabolism , Blotting, Western , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/pathology , Cell Cycle/physiology , Cell Line, Tumor , Cell Movement/physiology , Gene Expression Regulation, Neoplastic , Humans , Mutation , Neoplastic Stem Cells , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Phosphorylation , Transfection , Tumor Suppressor Protein p53/genetics
7.
Front Oncol ; 4: 218, 2014.
Article in English | MEDLINE | ID: mdl-25177547

ABSTRACT

Renal cell carcinoma (RCC) has a potential to metastasize to almost any site and this may occur many years following nephrectomy. We present six cases with uncommon sites of metastasis: four patients presented with distal pancreatic metastasis and two with duodenal/head of the pancreas metastasis. Time to metastatic disease varied from 1 to 19 years following renal surgery. For patients are alive and two succumbed to their disease. Long-term survival can be achieved with aggressive surgical excision of disease.

8.
JAMA Surg ; 149(5): 451-7, 2014 May.
Article in English | MEDLINE | ID: mdl-24671426

ABSTRACT

IMPORTANCE: In conjunction with chemotherapy, immunotherapy with dendritic cells (DCs) may eliminate minimal disease burden by generating cytotoxic T lymphocytes. Enhanced cytosolic bioavailability of tumor-specific antigens improves access to human leukocyte antigen (HLA) class I molecules for more efficient cytotoxic T lymphocyte generation. Various cell-penetrating domains (CPDs) are known to ferry covalently linked heterologous antigens to the intracellular compartment by traversing the plasma membrane. OBJECTIVE: To determine whether generating melanoma antigen family A, 3 (MAGE-A3), a tumor-specific cancer-testis antigen, as a fusion protein with CPD will enhance the cytosolic bioavailability of MAGE-A3. DESIGN: MAGE-A3 was amplified by polymerase chain reaction using complementary DNA from renal tissue and cloned in frame with a CPD (YARKARRQARR) at the amino-terminal end and hexahistidine at the carboxy-terminal end to generate CPD-MAGE-A3 in a pQE-70 expression vector. Cultures were grown in Escherichia coli BL21 Star (DE3-pLysS) cells followed by nickel-nitrilotriacetic acid affinity purification of recombinant proteins. MAIN OUTCOMES AND MEASURES: Measurement of DC membrane penetration of CPD-MAGE-A3 vs MAGE-A3 and determination of the effect of CPD-MAGE-A3 pulsing on DC phenotypic expression of cell-surface antigens. RESULTS: Media composition and isopropyl-d-thiogalactosidase induction were optimized to achieve high levels of protein expression followed by purification. Western blot analysis with MAGE-A3 antibodies recognized both MAGE-A3 and CPD-MAGE-A3 proteins, while CPD antibodies recognized only CPD-MAGE-A3. Purified CPD-MAGE-A3 exhibited more efficient DC membrane penetration than did MAGE-A3 alone as confirmed by immunofluorescence analysis. High-level expression of several unique DC markers (CD80, CD83, CD86, and HLA-DR) by flow cytometry was consistent with a mature DC phenotype, indicating that pulsing with CPD-MAGE-A3 did not alter specific cell-surface antigens required for T-cell activation. CONCLUSIONS AND RELEVANCE: We have demonstrated for the first time, to our knowledge, that cloning and purification of MAGE-A3 with CPD enhances its cytosolic bioavailability in DCs without altering cell-surface antigens, potentially making it a more potent therapeutic cancer vaccine compared with existing MAGE-A3 protein and peptide vaccines.


Subject(s)
Antigens, Neoplasm/therapeutic use , Cancer Vaccines/pharmacokinetics , Cancer Vaccines/therapeutic use , Cell Membrane Permeability/drug effects , Cytosol/drug effects , Cytosol/immunology , Dendritic Cells/drug effects , Dendritic Cells/immunology , Neoplasm Proteins/pharmacokinetics , Neoplasm Proteins/therapeutic use , Antigens, Neoplasm/immunology , Biological Availability , Cancer Vaccines/immunology , Cell Membrane Permeability/immunology , Cell-Penetrating Peptides , Cloning, Molecular , Drug Screening Assays, Antitumor , Humans , Neoplasm Proteins/immunology , T-Lymphocytes, Cytotoxic/drug effects , T-Lymphocytes, Cytotoxic/immunology
10.
Am J Surg Pathol ; 38(4): 480-93, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24451278

ABSTRACT

Pancreaticoduodenectomy (PD) specimens present a challenge for surgical pathologists because of the relative rarity of these specimens, combined with the anatomic complexity. Here, we describe our experience on the orientation, dissection, and sampling of PD specimens for a more practical and accurate evaluation of pancreatic, distal common bile duct (CBD), and ampullary tumors. For orientation of PDs, identification of the "trapezoid," created by the vascular bed at the center, the pancreatic neck margin on the left, and the uncinate margin on the right, is of outmost importance in finding all the pertinent margins of the specimen including the CBD, which is located at the upper right edge of this trapezoid. After orientation, all the margins can be sampled. We submit the uncinate margin entirely as a perpendicular inked margin because this adipose tissue-rich area often reveals subtle satellite carcinomas that are grossly invisible, and, with this approach, the number of R1 resections has doubled in our experience. Then, to ensure proper identification of all lymph nodes (LNs), we utilize the orange-peeling approach, in which the soft tissue surrounding the pancreatic head is shaved off in 7 arbitrarily defined regions, which also serve as shaved samples of the so-called "peripancreatic soft tissue" that defines pT3 in the current American Joint Committee on Cancer TNM. With this approach, our LN count increased from 6 to 14 and LN positivity rate from 50% to 73%. In addition, in 90% of pancreatic ductal adenocarcinomas there are grossly undetected microfoci of carcinoma. For determination of the primary site and the extent of the tumor, we believe bisectioning of the pancreatic head, instead of axial (transverse) slicing, is the most revealing approach. In addition, documentation of the findings in the duodenal surface of the ampulla is crucial for ampullary carcinomas and their recent site-specific categorization into 4 categories. Therefore, we probe both the CBD and the pancreatic duct from distal to the ampulla and cut the pancreatic head to the ampulla at a plane that goes through both ducts. Then, we sample the bisected pancreatic head depending on the findings of the case. For example, for proper staging of ampullary carcinomas, it is imperative to take the sections perpendicular to the duodenal serosa at the "groove" area, as ampullary carcinomas often extend to this region. Amputative (axial) sectioning of the ampulla, although good for documentation of the peri-Oddi spread of the intra-ampullary tumors, unfortunately disallows documentation of mucosal spread of the papilla of Vater tumors (those arising from the edge of the ampulla, where the ducts transition to duodenal mucosa and extending) into the neighboring duodenum. Axial sectioning also often fails to document tumor spread to the "groove" area. In conclusion, knowledge of the gross characteristics of the anatomic hallmarks is essential for proper dissection of PD specimens. The approach described above allows practical and accurate documentation and staging of pancreas, distal CBD, and ampullary cancers.


Subject(s)
Common Bile Duct Neoplasms/surgery , Pancreatic Neoplasms/surgery , Pancreaticoduodenectomy/methods , Ampulla of Vater/surgery , Humans
11.
Pharmaceuticals (Basel) ; 7(1): 46-57, 2014 Jan 09.
Article in English | MEDLINE | ID: mdl-24451403

ABSTRACT

Recent observations suggest a lower incidence of malignancies in patients infected with HIV during treatment with Highly Active Anti-Retroviral Therapy (HAART) utilizing protease inhibitors. We investigated the effects of ritonavir, a FDA approved HIV protease inhibitor, on proliferation of pancreatic ductal adeno-carcinoma (PDAC) cell lines. Human PDAC cell lines BxPC-3, MIA PaCa-2, and PANC-1 were propagated under standard conditions and treated with serial dilutions of ritonavir. Ritonavir inhibited cell growth in a dose-dependent manner as well as activated the intrinsic apoptotic pathway in human pancreatic ductal adenocarcinoma (PDAC) cell lines. We observed down-modulation of cell-cycle promoting and up-regulation of cell-cycle inhibitory genes; enhanced interaction of retinoblastoma protein (RB) with E2F-1 transcription factor; inhibition of phosphorylation of RB, resulting in sequestration of E2F-1 and subsequent down-regulation of S phase genes; decreased interaction of E2F-1 with its consensus binding sites; inhibition of cell motility and invasiveness; and inhibition of the AKT pathway. Our results demonstrate a potential use of ritonavir as part of combination chemotherapy for PDAC. Since ritonavir is FDA approved for HIV, drug repositioning for PDAC would limit the costs and reduce risks.

12.
Vaccine ; 32(8): 938-43, 2014 Feb 12.
Article in English | MEDLINE | ID: mdl-24406390

ABSTRACT

MAGE-A3 is highly expressed in epithelial ovarian cancer (EOC), making it a promising candidate for immunotherapy. We investigated whether dendritic cells (DCs) transduced with a rAAV-6 capsid mutant vector Y445F could elicit effective MAGE-A3-specific anti-tumor cytotoxic T lymphocyte (CTL) responses in vitro. MAGE-A3 was cloned and rAAV-6-MAGE-A3 purified, followed by proviral genome detection using real-time PCR. Immunofluorescence detection of rAAV-6-Y445F-MAGE-A3-transduced DCs demonstrated 60% transduction efficiency. Fluorescent in situ hybridization analysis confirmed chromosomal integration of rAAV vectors. Flow cytometric analysis of transduced DCs showed unaltered expression of critical monocyte-derived surface molecules with retention of allo-stimulatory activity. Co-culture of autologous T lymphocytes with MAGE-A3-expressing DCs produced CTLs that secreted IFN-γ, and efficiently killed MAGE-A3+ EOC cells. This form of rAAV-based DC immunotherapy, either alone or more likely in combination with other immune-enhancing protocols, may prove useful in the clinical setting for management of EOC.


Subject(s)
Antigens, Neoplasm/immunology , Immunotherapy , Neoplasm Proteins/immunology , Neoplasms, Glandular and Epithelial/pathology , Ovarian Neoplasms/pathology , T-Lymphocytes, Cytotoxic/immunology , Capsid , Carcinoma, Ovarian Epithelial , Cell Line, Tumor , Dendritic Cells/cytology , Dendritic Cells/immunology , Dependovirus/genetics , Genetic Vectors , Humans , Interferon-gamma/immunology , Lymphocyte Culture Test, Mixed , Mutation , Transduction, Genetic
13.
Surgery ; 154(4): 739-46; discussion 746-7, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24074410

ABSTRACT

PURPOSE: Enhancer of zeste homologue 2 (EZH2), a component of the chromatin modification protein complex, is upregulated in pancreatic ductal adenocarcinoma (PDAC), whereas loss of p53 and its downstream target, p21(waf1/cip1), is also observed frequently. We sought to investigate the role of the p53-p21(waf1/cip1) pathway in relation to EZH2-mediated inhibition of PDAC. METHODS: The PANC-1 cell line was utilized in chromatin immunoprecipitation, gene profiling, Western blot, cell invasion, cell proliferation, and tumor xenograft assays. RESULTS: Western blot analysis with antibodies that recognize both wild-type and mutant p53 did not show any alterations in band intensity; however, antibody that detects only mutant p53 showed a band of significantly lesser intensity with EZH2 knockdown. Western blot analysis further revealed a significant upregulation of p21(waf1/cip1). Gene expression profile analysis indicated significantly enhanced transcripts of transcriptional inducers of p21(waf1/cip1), with downregulation of mutant p53 transcript, corroborating the Western blot analysis. PANC-1 cells expressing EZH2-short hairpin RNA displayed markedly attenuated growth in SCID mice. CONCLUSION: Downregulation of mutant p53 with concomitant enhanced expression of p21(waf1/cip1) and its transcriptional trans-activators may contribute toward EZH2-mediated suppression of PDAC.


Subject(s)
Adenocarcinoma/genetics , Carcinoma, Pancreatic Ductal/genetics , Cyclin-Dependent Kinase Inhibitor p21/physiology , Genes, p53/physiology , Pancreatic Neoplasms/genetics , Polycomb Repressive Complex 2/physiology , RNA, Small Interfering/genetics , Adenocarcinoma/pathology , Animals , Apoptosis , Carcinoma, Pancreatic Ductal/pathology , Cell Line, Tumor , Cyclin-Dependent Kinase Inhibitor p21/genetics , Enhancer Elements, Genetic , Enhancer of Zeste Homolog 2 Protein , Humans , Mice , Pancreatic Neoplasms/pathology , Polycomb Repressive Complex 2/genetics , Up-Regulation
14.
Cancer Lett ; 336(1): 53-60, 2013 Aug 09.
Article in English | MEDLINE | ID: mdl-23603558

ABSTRACT

The enhancer of zeste homolog 2 (EZH2) methyltransferase is a transcriptional repressor. EZH2 is abnormally elevated in epithelial ovarian cancer (EOC). We demonstrated that EZH2 knockdown inhibited cell growth, activated apoptosis, and enhanced chemosensitivity. Further, silencing of EZH2 resulted in re-expression of p21(waf1/cip1) and down-regulation of mutant p53. Finally, EZH2 knockdown contributed to attenuated EOC growth in SCID mice.


Subject(s)
Cyclin-Dependent Kinase Inhibitor p21/metabolism , Gene Expression Regulation, Neoplastic , Ovarian Neoplasms/pathology , Polycomb Repressive Complex 2/metabolism , RNA Interference , Tumor Suppressor Protein p53/metabolism , Animals , Apoptosis , Cell Line, Tumor , Cell Proliferation , Cyclin-Dependent Kinase Inhibitor p21/genetics , Enhancer of Zeste Homolog 2 Protein , Female , Humans , Mice , Mice, SCID , Mutation , Neoplasm Invasiveness , Neoplasm Metastasis , Neoplasm Transplantation , Oligonucleotide Array Sequence Analysis , Ovarian Neoplasms/genetics , Polycomb Repressive Complex 2/genetics , Tumor Suppressor Protein p53/genetics
15.
Surgery ; 152(4): 704-11; discussion 711-3, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22943841

ABSTRACT

PURPOSE: To investigate the possibility of inhibiting the progression of pancreatic ductal adenocarcinoma (PDAC) by facilitating the expression of E-cadherin through the enforced expression of microRNA-101 (miR-101). METHODS: In situ hybridization was conducted with archival tissue using a double digoxigenin-labeled probe. Chromatin immunoprecipitation (ChIP) assay was conducted with EZ-Magna ChIPTM A. Gene profile analysis, Western blot, and immunoprecipitation assays were performed using standard protocols. RESULTS: We found that decreased miR-101 expression observed in archival patient tissues was significantly associated with poor prognosis indicated by low-intensity staining in high-grade tumors. ChIP assays using anti-enhancer of zeste homolog 2 (EZH2) antibodies indicated not only the interaction of EZH2 to the CDH1 (E-cadherin) promoter, but also that this interaction was significantly diminished in cells transfected with pre-miR-101. We observed a global downregulation of trimethylated lysine 27 of H3 histone (H3K27me3) along with upregulation of the enzymes histone deacetylase -1 and -2 with the re-expression of miR-101. Further, we observed lesser levels of transcriptional factors that inhibit the CDH1 promoter with pre-miR-101 treatment. Western blot analysis confirmed the enhanced E-cadherin expression. PANC-1 cells transduced with pre-miR-101 displayed markedly attenuated growth in SCID mice. CONCLUSION: These results suggest the potential therapeutic use of miR-101-enforced expression for inhibition of PDAC.


Subject(s)
Cadherins/genetics , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/therapy , MicroRNAs/therapeutic use , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/therapy , Adult , Aged , Animals , Antigens, CD , Apoptosis/genetics , Base Sequence , Carcinoma, Pancreatic Ductal/pathology , Case-Control Studies , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation , Female , Gene Expression , Humans , In Situ Hybridization , Male , Mice , Mice, SCID , MicroRNAs/genetics , Middle Aged , Neoplasm Invasiveness/genetics , Pancreatic Neoplasms/pathology , Promoter Regions, Genetic , Transduction, Genetic , Tumor Stem Cell Assay , Xenograft Model Antitumor Assays
16.
Pharm Res ; 28(12): 3079-90, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21818714

ABSTRACT

PURPOSE: MicroRNA-101 (miR-101) expression is negatively associated with tumor growth and proliferation in several solid epithelial cancers. Enhancer of zeste homolog 2 (EzH2) appears to be a functional target of miR-101. We explore the role of miR-101 and its interaction with EzH2 in epithelial ovarian carcinoma (EOC). METHODS: In situ hybridization (ISH) for miR-101 was performed on EOC patient tissues and normal controls. EOC cell lines were transfected with miR-101 and subjected to growth analysis and clonogenic assays. Cell motility was assessed by Boyden chamber and wound-healing assays. P21(waf1/cip1) and EzH2 interaction was assessed by Chromatin Immunoprecipitation (ChIP) assay in MDAH-2774 cells. SCID mice were assessed for tumor burden after injection with miR-101 or control vector-treated MDAH-2774 cells. RESULTS: ISH analysis revealed a decrease in miR-101 expression in EOC compared with normal tissue. MiR-101 re-expression in EOC cell lines resulted in increased apoptosis, decreased cellular proliferation, invasiveness, and reduced growth of tumor xenografts. CHIP assays revealed that re-expression of miR-101 inhibited the interaction of EzH2 with p21(waf1/cip1) promoter. CONCLUSIONS: MiR-101 re-expression appears to have antitumor effects, providing a better understanding of the role of miR-101 in EOC.


Subject(s)
Chromatin/genetics , Cyclin-Dependent Kinase Inhibitor p21/genetics , DNA-Binding Proteins/genetics , MicroRNAs/genetics , Neoplasms, Glandular and Epithelial/genetics , Neoplasms, Glandular and Epithelial/pathology , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Transcription Factors/genetics , Animals , Apoptosis , Carcinoma, Ovarian Epithelial , Cell Line, Tumor , Cell Proliferation , Chromatin/metabolism , Cyclin-Dependent Kinase Inhibitor p21/metabolism , DNA-Binding Proteins/metabolism , Enhancer of Zeste Homolog 2 Protein , Female , Gene Expression Regulation, Neoplastic , Humans , Male , Mice , Mice, SCID , MicroRNAs/metabolism , Neoplasm Invasiveness/genetics , Neoplasm Invasiveness/pathology , Neoplasms, Glandular and Epithelial/metabolism , Ovarian Neoplasms/metabolism , Ovary/metabolism , Ovary/pathology , Polycomb Repressive Complex 2 , Transcription Factors/metabolism
17.
Methods Mol Biol ; 755: 245-56, 2011.
Article in English | MEDLINE | ID: mdl-21761309

ABSTRACT

Pure populations of tumor cells are essential for the identification of tumor-associated proteins for the development of targeted therapy. In recent years, laser capture microdissection (LCM) has been used successfully to obtain distinct populations of cells for subsequent molecular analysis. The polycomb group (PcG) protein, enhancer of zeste homolog 2 (EzH2), a methyl-transferase that plays a key role in -transcriptional gene repression, is frequently overexpressed in several malignant tumors. High levels of EzH2 are often associated with advanced disease stage in many solid tumors; however, its role in the pathogenesis of pancreatic ductal adeno-carcinoma (PDAC) is poorly understood. Because of the limited sample availability and the absence of in vitro amplification steps for proteins, the use of LCM for proteomics studies largely depends on highly sensitive protein detection methods. Here, we developed a faster and sensitive Western blot protocol and validated it for the detection of EzH2 in ∼2,000 cells. Initially, cultured PANC-1 cells were used to optimize protein electrophoresis and western blotting conditions. Gradient gel electrophoresis in combination with optimized antibody concentrations, and a sensitive chemiluminescent assay provided a strong signal. In order to further confirm the role of EzH2 in PDAC, employing siRNA-mediated gene silencing via long lasting plasmid vectors containing shRNA, we investigated the potential role of EzH2 gene silencing in pancreatic cancer regression. Positive correlation of EzH2 expression was observed with advanced stage, serous histology, and increasing grade in pancreatic cancer patient tissues. Further EzH2 knockdown resulted in decreased cell growth and invasiveness. The findings of this study emphasize that western blotting of a LCM-generated pure population of cancer cells may be a valuable technique for the study of tumor-specific proteins.


Subject(s)
Blotting, Western/methods , Carcinoma, Pancreatic Ductal/metabolism , DNA-Binding Proteins/metabolism , Lasers , Microdissection/methods , Pancreatic Neoplasms/metabolism , Transcription Factors/metabolism , Animals , Carcinoma, Pancreatic Ductal/pathology , Cell Migration Assays/methods , Cell Proliferation , Cell Separation/methods , Cryopreservation , Electrophoresis, Polyacrylamide Gel/methods , Enhancer of Zeste Homolog 2 Protein , Humans , Microtomy/methods , Pancreatic Neoplasms/pathology , Polycomb Repressive Complex 2 , Rats , Staining and Labeling/methods , Tumor Cells, Cultured
18.
Transl Oncol ; 3(6): 389-99, 2010 Dec 01.
Article in English | MEDLINE | ID: mdl-21151478

ABSTRACT

INTRODUCTION: The incidence of Barrett esophageal adenocarcinoma (BEAC) has been increasing at an alarming rate in western countries. In this study, we have evaluated the therapeutic potential of sulforaphane (SFN), an antioxidant derived from broccoli, in BEAC. METHODS: BEAC cells were treated with SFN, alone or in combination with chemotherapeutic, paclitaxel, or telomerase-inhibiting agents (MST-312, GRN163L), and live cell number determined at various time points. The effect on drug resistance/chemosensitivity was evaluated by rhodamine efflux assay. Apoptosis was detected by annexin V labeling and Western blot analysis of poly(ADP-ribose) polymerase cleavage. Effects on genes implicated in cell cycle and apoptosis were determined by Western blot analyses. To evaluate the efficacy in vivo, BEAC cells were injected subcutaneously in severe combined immunodeficient mice, and after the appearance of palpable tumors, mice were treated with SFN. RESULTS: SFN induced both time- and dose-dependent decline in cell survival, cell cycle arrest, and apoptosis. The treatment with SFN also suppressed the expression of multidrug resistance protein, reduced drug efflux, and increased anticancer activity of other antiproliferative agents including paclitaxel. A significant reduction in tumor volume was also observed by SFN in a subcutaneous tumor model of BEAC. Anticancer activity could be attributed to the induction of caspase 8 and p21 and down-regulation of hsp90, a molecular chaperon required for activity of several proliferation-associated proteins. CONCLUSIONS: These data indicate that a natural product with antioxidant properties from broccoli has great potential to be used in chemoprevention and treatment of BEAC.

19.
Mol Cancer ; 9: 47, 2010 Mar 02.
Article in English | MEDLINE | ID: mdl-20196847

ABSTRACT

BACKGROUND: Sulforaphane (SFN), an isothiocyanate phytochemical present predominantly in cruciferous vegetables such as brussels sprout and broccoli, is considered a promising chemo-preventive agent against cancer. In-vitro exposure to SFN appears to result in the induction of apoptosis and cell-cycle arrest in a variety of tumor types. However, the molecular mechanisms leading to the inhibition of cell cycle progression by SFN are poorly understood in epithelial ovarian cancer cells (EOC). The aim of this study is to understand the signaling mechanisms through which SFN influences the cell growth and proliferation in EOC. RESULTS: SFN at concentrations of 5-20 microM induced a dose-dependent suppression of growth in cell lines MDAH 2774 and SkOV-3 with an IC50 of ~8 microM after a 3 day exposure. Combination treatment with chemotherapeutic agent, paclitaxel, resulted in additive growth suppression. SFN at ~8 microM decreased growth by 40% and 20% on day 1 in MDAH 2774 and SkOV-3, respectively. Cells treated with cytotoxic concentrations of SFN have reduced cell migration and increased apoptotic cell death via an increase in Bak/Bcl-2 ratio and cleavage of procaspase-9 and poly (ADP-ribose)-polymerase (PARP). Gene expression profile analysis of cell cycle regulated proteins demonstrated increased levels of tumor suppressor retinoblastoma protein (RB) and decreased levels of E2F-1 transcription factor. SFN treatment resulted in G1 cell cycle arrest through down modulation of RB phosphorylation and by protecting the RB-E2F-1 complex. CONCLUSIONS: SFN induces growth arrest and apoptosis in EOC cells. Inhibition of retinoblastoma (RB) phosphorylation and reduction in levels of free E2F-1 appear to play an important role in EOC growth arrest.


Subject(s)
Cell Cycle/drug effects , E2F1 Transcription Factor/metabolism , Epithelial Cells/pathology , Ovarian Neoplasms/metabolism , Ovarian Neoplasms/pathology , Retinoblastoma Protein/metabolism , Thiocyanates/pharmacology , Apoptosis/drug effects , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , DNA, Neoplasm/biosynthesis , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , Isothiocyanates , Neoplasm Invasiveness , Oligonucleotide Array Sequence Analysis , Ovarian Neoplasms/genetics , Paclitaxel/pharmacology , Phosphorylation/drug effects , S Phase/drug effects , Sulfoxides , Wound Healing/drug effects
20.
Am J Surg ; 199(1): 52-9, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20103066

ABSTRACT

BACKGROUND: Sciatic hernias are considered the rarest pelvic floor hernias, with a very limited number of published reports worldwide. The condition has received limited attention in the surgical literature. DATA SOURCES: The data reported herein are based on a literature review including MEDLINE and CURRENT CONTENTS computerized database searches. The existing bibliographies on sciatic hernia were explored for articles pertaining to the review. Finally, the Internet was searched for articles not listed in the available medical databases. CONCLUSIONS: Sciatic hernia is unusual, and can present the physician with diagnostic and treatment dilemmas. The hernia may present with obscure pelvic pain, intestinal obstruction, life-threatening gluteal sepsis, or as an asymptomatic, reducible mass that distorts the gluteal fold. Small sciatic hernia can remain hidden behind the gluteus maximus muscle. The diagnosis requires imaging studies in such cases. Treatment of sciatic hernia is always surgical and requires prosthetic reinforcement for the best result.


Subject(s)
Diagnostic Imaging/methods , Hernia/diagnosis , Herniorrhaphy , Pelvic Bones , Female , Humans , Male , Pelvic Floor/physiopathology , Pelvic Pain/physiopathology , Prognosis , Rare Diseases , Risk Assessment , Sciatic Nerve , Severity of Illness Index , Surgical Procedures, Operative/methods , Treatment Outcome
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