|ognizant Communication Corporation|
Featuring PRECLINICAL AND CLINICAL CANCER THERAPEUTICS
VOLUME 17, NUMBER 8
Oncology Research, Vol. 17, pp. 339-345
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Bone Marrow-Derived Progenitor Cells Could Modulate Pancreatic Cancer Tumorigenesis via Peritumoral Microenvironment in a Rat Model
Jen-Jung Pan,1 Seh-Hoon Oh,2 Wayne C. Lee,3 and Bryon E. Petersen2
1Division of Gastroenterology, Hepatology, and Nutrition,
Department of Medicine, University of Florida, Gainesville, FL, USA
2Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, FL, USA
3Department of Surgery, University of Florida, Gainesville, FL, USA
Metaplastic tubular complexes (MTC) have been proposed as precursor lesions for pancreatic adenocarcinoma (PDAC). In this study, we investigated the potential role of bone marrow-derived progenitor cells (BMPC) in the formation of MTC and PDAC in a rat model. F344 rats defective for CD26 (dipeptidyl peptidase IV, DPPIV) expression were sublethally irradiated and received rescue bone marrow cells from wild-type F344 rats that express CD26. After confirming engraftment, recipient animals received dimethylbenzanthracene (DMBA) implantation in their pancreas. Animals were sacrificed monthly from 3 to 7 months. We observed both MTC and tumors in animals that received DMBA. These MTC were ductal complexes because they stained positive for cytokeratin but were negative for chymotrypsin and chromogranin A. Cells that expressed both CD26 and cytokeratin were rarely observed in the MTC. Cells expressing either both CD26 and CD45 or CD26 and smooth muscle actin were also found near the MTC. However, no CD26 signal was detected in the tumors. Within this model, there appeared to be no evidence supporting that BMPC turned into tumor cells directly. BMPC could modulate pancreatic cancer growth through tumor microenvironment.
Key words: Bone marrow; Progenitor cell; Pancreatic cancer; Tumorigenesis; Microenvironment
Address correspondence to Jen-Jung Pan, M.D., Ph.D., Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, University of Florida, 1600 SW Archer Road, P.O. Box 100214, Gainesville, FL 32610, USA. Tel: (352)392-7353; Fax: (352)392-7393; E-mail: firstname.lastname@example.org
COX-2 Polymorphisms in Patients With Familial Adenomatous Polyposis
Wilbert H. M. Peters,1 Rene H. M. te Morsche,1 Hennie M. J. Roelofs,1 Elisabeth M. H. Mathus-Vliegen,2 Marloes Berkhout,1 and Fokko M. Nagengast1
1Department of Gastroenterology, Radboud University Nijmegen
Medical Center, Nijmegen, The Netherlands
2Academic Medical Center, Amsterdam, The Netherlands
Cyclooxygenase-2 (COX-2) is an enzyme involved in the synthesis of prostaglandins and thromboxanes, which are regulators of biologic processes such as inflammation, cell proliferation, and angiogenesis. COX-2 has been found overexpressed in (pre)malignant tissues and may be relevant to cancer development. We investigated whether functional genetic polymorphisms in COX-2 may have a risk-modifying effect on duodenal adenomatosis in patients with familial adenomatous polyposis (FAP). Blood from 85 patients with FAP and 218 age- and sex-matched healthy subjects was investigated for the presence of two functional promoter region polymorphisms (-1195G ->A and -765G ->C) in COX-2. Logistic regression analysis revealed an overrepresentation of the -1195GG genotype compared to the -1195AA genotype in patients with FAP (odds ratio = 2.81; 95% CI = 1.00-7.91, p = 0.042). No associations between single COX-2 polymorphisms or COX-2 haplotype were found when patients were evaluated according to their Spigelman stage. The predicted low COX-2 expression genotype -1195GG was found overrepresented in the patients with FAP. The COX-2 genotypes showed no association with the severity of duodenal adenomatosis.
Key words: Familial adenomatous polyposis; Cyclooxygenase-2; Genetic polymorphism; Duodenal adenomatosis
Address correspondence to Wilbert H. M. Peters, Ph.D., Department of Gastroenterology, Radboud University Nijmegen Medical Center, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands. E-mail: email@example.com
Identification of Endogenous Reference Genes for qRT-PCR Analysis in Normal Matched Breast Tumor Tissues
Bala Gur-Dedeoglu,1 Ozlen Konu,1 Betul Bozkurt,2 Gulusan Ergul,3 Selda Seckin,3 and Isik G. Yulug1
1Department of Molecular Biology and Genetics, Faculty of
Science, Bilkent University, Ankara, Turkey
2Department of General Surgery, Ankara Numune Research and Teaching Hospital, Ankara, Turkey
3Department of Pathology, Ankara Numune Research and Teaching Hospital, Ankara, Turkey
Quantitative gene expression measurements from tumor tissue are frequently compared with matched normal and/or adjacent tumor tissue expression for diagnostic marker gene selection as well as assessment of the degree of transcriptional deregulation in cancer. Selection of an appropriate reference gene (RG) or an RG panel, which varies depending on cancer type, molecular subtypes, and the normal tissues used for interindividual calibration, is crucial for the accurate quantification of gene expression. Several RG panels have been suggested in breast cancer for making comparisons among tumor subtypes, cell lines, and benign/malignant tumors. In this study, expression patterns of 15 widely used endogenous RGs (ACTB, TBP, GAPDH, SDHA, HPRT, HMBS, B2M, PPIA, GUSB, YWHAZ2, PGK1, RPLP0, PUM1, MRPL19, and RPL41), and three candidate genes that were selected through analysis of two independent microarray datasets (IL22RA1, TTC22, ZNF224) were determined in 23 primary breast tumors and their matched normal tissues using qRTPCR. Additionally, 18S rRNA, ACTB, and SDHA were tested using randomly primed cDNAs from 13 breast tumor pairs to assess the rRNA/mRNA ratio. The tumors exhibited significantly lower rRNA/mRNA ratio when compared to their normals, on average. The expression of the studied RGs in breast tumors did not exhibit differences in terms of grade, ER, or PR status. The stability of RGs was examined based on two different statistical models, namely GeNorm and NormFinder. Among the 18 tested endogenous reference genes, ACTB and SDHA were identified as the most suitable reference genes for the normalization of qRTPCR data in the analysis of normal matched tumor breast tissue pairs by both programs. In addition, the expression of the gelsolin (GSN) gene, a well-known downregulated target in breast tumors, was analyzed using the two most suitable genes and different RG combinations to validate their effectiveness as a normalization factor (NF). The GSN expression of the tumors used in this study was significantly lower than that of normals showing the effectivity of using ACTB and SDHA as suitable RGs in this set of tumor-normal tissue panel. The combinational use of the best performing two RGs (ACTB and SDHA) as a normalization factor can be recommended to minimize sample variability and to increase the accuracy and resolution of gene expression normalization in tumor-normal paired breast cancer qRT-PCR studies.
Key words: Real-time quantitative RT-PCR; Endogenous reference genes; Normalization factor; Breast cancer
Address correspondence to Isik G. Yulug, Ph.D., Department of Molecular Biology and Genetics, Bilkent University, Faculty of Science, TR-06800 Ankara, Turkey. Tel: +90-312-290-2506; Fax: +90-312-266-5097; E-mail: firstname.lastname@example.org
Breast Cancer Risk Associated With Polymorphisms of IL-1RN and IL-4 Gene in Indian Women
Rituraj Konwar,1 Preeti Chaudhary,1 Sandeep Kumar,2 Deepti Mishra,2 Naibedya Chattopadhyay,1 and Hemant Kumar Bid1
1Endocrinology Division, Central Drug Research Institute
(CDRI), Lucknow, India
2King George Medical University (KGMU), Lucknow, India
Interleukins and cytokines are important regulator of the aetio-pathogenesis of the majority of cancers. Mechanistic role of IL-1RN and IL-4, particularly in breast carcinogenesis, is well documented. However, the role of polymorphisms of IL-1RN and IL-4 combinations associated with risk of breast cancer is not reported. The IL-1RN and IL-4 gene polymorphisms were genotyped with VNTR-PCR in 100 patients (benign tumor n = 32 and breast cancer n = 68) and 200 normal healthy control subjects with normal mammogram. Genotype distribution and allelic frequencies between patients and controls were compared and odds ratios (OR) with 95% confidence intervals (CI) were calculated using SPSS software (version 12.0). There were no significant differences in the genotype distributions of both IL-1RN and IL-4 polymorphisms between cases and controls. Similarly, subgroup analysis showed that there is no significant association for pre- and postmenopausal women. However, BB genotype of IL-1RN significantly differs among benign and malignant stages of breast cancer. IL-1RN and IL-4 polymorphisms alone or in combination are not associated with risk of breast cancer in Indian patients. The association of IL-1RN with malignant stages may indicate its possible role in progression of breast cancer. Further studies in other population are needed to confirm our findings and to elucidate the role of IL-1RN in progression of breast cancer.
Key words: Breast cancer; IL-1RN; IL-4; Polymorphism; Risk
Address correspondence to Hemant Kumar Bid, Ph.D., Endocrinology Division, Central Drug Research Institute (CDRI), Lucknow-226 001 India. Tel: +91-522-2613894, Ext. 4306; Fax: +91-522-2623405; E-mail: email@example.com
Sodium Selenite Induces Apoptosis in Acute Promyelocytic Leukemia-Derived NB4 Cells Through Mitochondria-Dependent Pathway
Bingshe Han,1,2 Yun Ren,1 Liying Guan,1 Wei Wei,1 Fangyuan Hua,1 Yang Yang,1 Tao Yang,1 Tingming Cao,1 Hua Dong,1 Huazhen Pan,1 and Caimin Xu1
1National Key Laboratory of Medical Molecular Biology, Institute
of Basic Medical Sciences, Peking Union Medical College and Chinese Academy
of Medical Sciences, Beijing, China
2Department of Biochemistry and Molecular Biology, Shanxi Medical University, Taiyuan, Shanxi Province, China
Our previous study has shown that sodium selenite can cause apoptosis in acute promyelocytic leukemia-derived NB4 cells in a caspase-dependent manner involving DYm disruption and cleavage of Bcl-2, but more detailed mechanism(s) remain unclear. Here we showed that mitochondrial apoptosis signaling pathway played a vital role in apoptosis induced by sodium selenite based on the following findings: 1) cytochrome c release, activation of caspase 9, mitochondrial targeting, and oligermerization of Bax; 2) caspase 9 , but not caspase 8, inhibitor could attenuate apoptosis; 3) downregulation of Bax and Bad by siRNA could delay sodium selenite-induced apoptosis. Further investigation showed that ROS was an essential inducer of DYm disruption and apoptosis by sodium selenite. Our findings here demonstrate that sodium selenite can induce apoptosis in NB4 cells through a mechanism involving ROS, activation of proapoptotic proteins Bad and Bax, DYm disruption, release of cytochrome c, and consequent initiation of caspase cascade.
Key words: Sodium selenite; Apoptosis; Acute promyelocytic leukemia-derived NB4 cells; Bcl-2 family; Reactive oxygen species
Address correspondence to Caimin Xu, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, CAMS & PUMC, 5 Dongdan Santiao, Dongcheng District, Beijing, 100005, China. Tel/Fax: 86-10-65296445; E-mail: firstname.lastname@example.org
Endothelin-1 Inhibition by Ambrisentan as a Potential Treatment Adjunct After Debulking Surgery in Epithelial Ovarian Cancer
R. E. Kast
Department of Psychiatry, University of Vermont, Burlington, VT, USA
The 21 amino acid signaling peptide endothelin-1 is commonly elevated in epithelial ovarian cancer, and it mediates or facilitates much of this cancer's aggressive behavior. Ambrisentan (Letairis; Gilead Sciences Inc.) is an antagonist of endothelin-1 at its cognate receptor that has just been approved to treat pulmonary hypertension. Ambrisentan is a well-tolerated pill taken once daily. In theory, it should retard and inhibit lodgement and establishment of disseminated peritoneal micrometastases after debulking surgery.
Key words: Ambrisentan; Endothelin; Epithelial ovarian cancer; Micrometastases; Metaplasia
Address correspondence to R. E. Kast, Department of Psychiatry, University of Vermont, 2 Church Street, Burlington, VT 05401, USA. Tel: 802-863-2462; E-mail: email@example.com