203 results on '"Oyasu R"'
Search Results
2. Nrf2 and p53 cooperatively protect against BBN-induced urinary bladder carcinogenesis
- Author
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Iida, K., primary, Itoh, K., additional, Maher, J. M., additional, Kumagai, Y., additional, Oyasu, R., additional, Mori, Y., additional, Shimazui, T., additional, Akaza, H., additional, and Yamamoto, M., additional
- Published
- 2007
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3. Balance between activated-STAT and MAP kinase regulates the growth of human bladder cell lines after treatment with epidermal growth factor.
- Author
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Kawamata, H, primary, Hattori, K, additional, Omotehara, F, additional, Uchida, D, additional, Hino, S, additional, Sato, M, additional, and Oyasu, R, additional
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- 1999
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4. Epithelial tumours of the lower urinary tract in humans and rodents
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Oyasu, R., primary
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- 1995
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5. ras gene alterations in invasive and non-invasive rat bladder carcinomas induced by N-methyl-N-nitrosourea
- Author
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Yura, Y, primary, Azuma, M, additional, Uchida, K, additional, Momose, H, additional, and Oyasu, R, additional
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- 1991
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6. Involvement of urine in epithelial-stromal interactions in urinary bladder carcinogenesis
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Momose, H., primary, Uchida, K., additional, Kakinuma, H., additional, Yura, Y., additional, and Oyasu, R., additional
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- 1990
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7. World Health Organization and International Society of Urological Pathology classification and two-number grading system of bladder tumors.
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Oyasu, Ryoichi and Oyasu, R
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- 2000
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8. Metaplastic squamous cell carcinoma of bronchus simulating giant cell tumor of bone.
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Oyasu, Ryoichi, Battifora, Hector A., Buckingham, William B., Hidvegi, Denise, Oyasu, R, Battifora, H A, Buckingham, W B, and Hidvegi, D
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- 1977
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9. Induction of high-grade, high-stage carcinomas in the rat urinary bladder.
- Author
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Oyasu, Ryoichi, Samma, Shoji, Ozono, Seiichiro, Bauer, Kenneth, Wallemark, Carl-Bertil, Homma, Yukio, Oyasu, R, Samma, S, Ozono, S, Bauer, K, Wallemark, C B, and Homma, Y
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- 1987
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10. Antisense RNA-mediated reduction of p53 induces malignant phenotype in nontumorigenic rat urothelial cells.
- Author
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Okamoto, M, Hattori, K, Fujimoto, K, Tanaka, Y, Gloosby, CL, and Oyasu, R
- Abstract
p53 mutation is commonly associated with high-grade high-stage human urothelial carcinomas. Recent studies suggest that p53 mutation in low-grade, low-stage bladder carcinomas may be correlated with the progression of the disease. In the present study, we used antisense RNA methodology in vitro to evaluate the significance of the loss of p53 function at an early stage of urinary bladder carcinogenesis. An immortalized nontumorigenic rat urothelial cell line (MYP3) that strongly expresses wild-type (WT) p53 was transfected with a plasmid (pcDL-SRα-296) containing a rat WT p53 cDNA in antisense orientation. The transfection resulted in a significant reduction in p53 mRNA expression and protein synthesis, in stimulation of anchorage-dependent growth, and in acquisition of anchorage-independent growth potential. Three such clones, when tested in athymic nude mice, all formed muscle-invasive, high-grade transitional cell carcinomas at s.c. injection sites. When cells were inoculated into an orthotopic site (urinary bladder), one of two antisense transfectants tested formed bulky tumors in the bladder in all seven nude mice and metastases to lungs in three of the seven mice. Analysis of these cells revealed a decrease in the expression of p21 (WAF1, sdi1, or CIP1) and retinoblastoma (Rb gene product. Phosphorylation of Rb protein was not inhibited when the cells were starved. No significant difference was observed in the expression of p16 protein. In cell cycle analysis, all antisense transfectants tested escaped from G1 arrest by starvation. Furthermore, secretion of interleukin (IL)-6 into culture medium was increased significantly. Treatment with anti-IL-6 antibody suppressed anchorage-dependent growth. This study directly demonstrates that the loss of p53 function at an early stage of urothelial carcinogenesis may result in acquisition of a malignant phenotype by regulating IL-6 production as well as cell cycle related genes. [ABSTRACT FROM PUBLISHER]
- Published
- 1998
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- View/download PDF
11. Transforming growth factor beta type I receptor acts as a potent tumor suppressor in rat bladder carcinoma.
- Author
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Hattori, K, Okamoto, M, and Oyasu, R
- Abstract
Transforming growth factor beta1 (TGFbeta1) is a potent growth inhibitor for most cells, including neoplastic cells. However, there are several types of malignant cells that are resistant to its growth-inhibitory effect. LMC19, a highly malignant rat urothelial cell line, lacks TGFbeta1 receptor (TbetaRI) and is insensitive to the growth-suppresive effect of TGFbeta1. We transfected an expression vector containing human TbetaRI into this cell line. In control cells transfected with the neo gene alone, no inhibitory effect on growth was observed in vitro by the addition of anti-TGFbeta1 antibody or recombinant TGFbeta1 into serum-free medium. In contrast, the growth of all transfectants tested was inhibited significantly under serum-free conditions because of their endogenous TGFbeta synthesis. The growth was reduced further by the addition of recombinant TGFbeta1. This response pattern is consistent with TGFbeta1 mediating its effects by an autocrine and paracrine mechanism. The tumorigenicity of the cells was tested in a heterotopically transplanted urinary bladder system, which was generated as an orthotopic test site in athymic nude mice. All nine mice tested receiving control cells formed deeply invasive, undifferentiated-cell carcinomas and multiple metastatic foci in the lungs. In contrast, none of the mice receiving transfectants of TbetaRI formed bladder tumors or metastases. Taken together, these observations indicate that TbetaRI exhibits a potent tumor suppressor effect in bladder carcinoma. [ABSTRACT FROM PUBLISHER]
- Published
- 1997
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12. Hepatocyte growth factor is an invasion/migration factor of rat urothelial carcinoma cells in vitro
- Author
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Tamatani, T., Hattori, K., Iyer, A., Tamatani, K., and Oyasu, R.
- Abstract
Hepatocyte growth factor (HGF) plays an important role in the growth, progression and angiogenesis of various tumors. It is reported that patients with urinary bladder cancer have elevated levels of HGF in urine and that bladder cancer tissue contains an increased amount of HGF. Thus, the data suggest a functional role of HGF in urinary bladder cancer. We evaluated the mechanistic role of HGF in urinary bladder carcinoma in vitro using the rat urothelial cell lines MYP3 (anchorage-dependent and non-tumorigenic in athymic nude mice), LMC19, MYU3L, T6 and AS-HTB1 (anchorage-independent and tumorigenic). The HGF receptor c-met was expressed by all of the cell lines, as determined by northern blot. In MYP3 cells, HGF strongly stimulated anchorage-dependent growth, but not migration, invasion or secretion of matrix metalloproteinases (MMPs). In LMC19, T6 and AS-HTB1 cells, HGF stimulated migration, invasion and secretion of MMPs. Anchorage-dependent growth stimulation was limited to AS-HTB1 cells. MYU3L cells were refractory to HGF in both growth and invasion assays. However, a neutralizing antibody and an anti-sense oligonucleotide to HGF partially inhibited the growth only of MYU3L cells, the finding being indicative of an autocrine stimulatory mechanism. HGF mRNA expression and protein synthesis were induced in bladder stromal cells by the conditioned medium of carcinoma cell lines, and IL-1β and basic fibroblast growth factor were identified as cancer cell-derived HGF-releasing factors. These results suggest that HGF acts as a mitogen in a non-tumorigenic cell line, whereas in tumorigenic cell lines it acts as an invasion and migration factor by either a paracrine or an autocrine mechanism.
- Published
- 1999
13. Antisense RNA-mediated reduction of p53 induces malignant phenotype in nontumorigenic rat urothelial cells
- Author
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Oyasu, R., Okamoto, M., Hattori, K., Fujimoto, K., Tanaka, Y., and Gloosby, C.
- Abstract
p53 mutation is commonly associated with high-grade high-stage human urothelial carcinomas. Recent studies suggest that p53 mutation in low-grade, low-stage bladder carcinomas may be correlated with the progression of the disease. In the present study, we used antisense RNA methodology in vitro to evaluate the significance of the loss of p53 function at an early stage of urinary bladder carcinogenesis. An immortalized nontumorigenic rat urothelial cell line (MYP3) that strongly expresses wild-type (WT) p53 was transfected with a plasmid (pcDL-SRα-296) containing a rat WT p53 cDNA in antisense orientation. The transfection resulted in a significant reduction in p53 mRNA expression and protein synthesis, in stimulation of anchorage-dependent growth, and in acquisition of anchorage-independent growth potential. Three such clones, when tested in athymic nude mice, all formed muscle-invasive, high-grade transitional cell carcinomas at s.c. injection sites. When cells were inoculated into an orthotopic site (urinary bladder), one of two antisense transfectants tested formed bulky tumors in the bladder in all seven nude mice and metastases to lungs in three of the seven mice. Analysis of these cells revealed a decrease in the expression of p21 (WAF1, sdi1, or CIP1) and retinoblastoma (Rb gene product. Phosphorylation of Rb protein was not inhibited when the cells were starved. No significant difference was observed in the expression of p16 protein. In cell cycle analysis, all antisense transfectants tested escaped from G1 arrest by starvation. Furthermore, secretion of interleukin (IL)-6 into culture medium was increased significantly. Treatment with anti-IL-6 antibody suppressed anchorage-dependent growth. This study directly demonstrates that the loss of p53 function at an early stage of urothelial carcinogenesis may result in acquisition of a malignant phenotype by regulating IL-6 production as well as cell cycle related genes.
- Published
- 1998
14. Sequential bilateral germ cell testicular tumors of different cell types.
- Author
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Mittal, B., Oyasu, R., and Brand, W. N.
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- 1981
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15. Prostate Specific Antigen and Acid Phosphatase-Reactive Cells in Cystitis Cystica and Glandularis
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Nowels, K., primary, Kent, E., additional, Rinsho, K., additional, and Oyasu, R., additional
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- 1989
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16. Pure seminoma
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Mittal, B., primary, Oyasu, R., additional, and Brand, W.N., additional
- Published
- 1981
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17. Stimulation of Rat Bladder Epithelial DNA Synthesis by Intravesical Instillation of Distilled Water
- Author
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Ozono, S., primary, Lee, I. C., additional, Weinstein, R. S., additional, and Oyasu, R., additional
- Published
- 1986
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18. In Vitro Interaction of Estrogen and Prolactin on Hormone-Dependent Rat Mammary Tumors
- Author
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Lee, C., primary, Oyasu, R., additional, and Chen, C., additional
- Published
- 1975
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19. Effects of urinary transferrin and ornithine decarboxylase-inducing fraction on rat bladder carcinogenesis
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Noguchi, S., primary, Yura, Y., additional, Hayashi, O., additional, Samma, S., additional, and Oyasu, R., additional
- Published
- 1989
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20. Enhancement by Urine of Urinary Bladder Carcinogenesis
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Oyasu, R., primary, Hirao, Y., additional, and Izumi, K., additional
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- 1982
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21. Interleukin-6 functions as an autocrine growth factor in human bladder carcinoma cell lines in vitro
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Okamoto, M., Hattori, K., and Oyasu, R.
- Subjects
Interleukin-6 -- Physiological aspects -- Growth ,Bladder cancer -- Physiological aspects ,Cancer cells -- Growth -- Physiological aspects ,Health ,Company growth ,Physiological aspects ,Growth - Abstract
Okamoto, M.; Hattori, K.; Oyasu, R. 'Interleukin-6 Functions as an Autocrine Growth Factor in Human Bladder Carcinoma Cell Lines in vitro.' International Journal of Cancer, July 3, 1997;72(1):149-154. According to [...]
- Published
- 1997
22. Angiogenesis inhibitor TNP-470 suppresses tumorigenesis in rat urinary bladder
- Author
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Tanaka, Y., Kawamata, H., Fujimoto, K., and Oyasu, R.
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Neovascularization -- Prevention -- Models ,Bladder cancer -- Models -- Prevention ,Health ,Prevention ,Models - Abstract
Tanaka, Y.; Kawamata H.; Fujimoto, K.; Oyasu, R. 'Angiogenesis Inhibitor TNP-470 Suppresses Tumorigenesis in Rat Urinary Bladder.' Journal of Urology, February 1997;157(2):683-688. According to the authors' abstract of an article [...]
- Published
- 1997
23. In vitro radiation-induced neoplastic progression of low-grade uroepithelial tumors
- Author
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Oyasu, R [Northwestern Univ. Medical School, Chicago, IL (United States)]
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- 1994
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24. Inactivation of AR activates HGF/c-Met system in human prostatic carcinoma cells.
- Author
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Maeda A, Nakashiro K, Hara S, Sasaki T, Miwa Y, Tanji N, Yokoyama M, Hamakawa H, and Oyasu R
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- Cell Line, Tumor, Down-Regulation, Extracellular Signal-Regulated MAP Kinases physiology, Humans, Male, RNA, Small Interfering pharmacology, Signal Transduction physiology, Hepatocyte Growth Factor physiology, Prostatic Neoplasms physiopathology, Proto-Oncogene Proteins c-met physiology, Receptors, Androgen physiology
- Abstract
Clinical studies with prostate cancer tissue indicate that alterations in androgen receptor (AR) or c-Met overexpression are associated with androgen-independent progression. We investigated the interaction between AR and c-Met signaling in human prostate cancer cells. Androgen withdrawal or AR-specific small interfering RNA significantly reduced the growth rate while each maneuver induced the expression of c-Met. Knockdown of both AR and c-Met expression markedly inhibited the cell growth. Furthermore, microarray analysis indicated that the activation of c-Met down-regulated the expression of DNA repair-related genes including 8-oxoguanine DNA glycosylase. Exogenous hepatocyte growth factor also induced the production of intracellular reactive oxygen species and resulted in the accumulation of DNA damages. These results suggested that the activation of c-Met signaling may lead to induction of spontaneous mutations or genomic instability, which may lead to the progression of androgen-independent state. Thus, c-Met signaling is utilized for survival and growth under the androgen-depleted condition.
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- 2006
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25. Bladder reconstruction using a collagen patch prefabricated within the omentum.
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Hattori K, Joraku A, Miyagawa T, Kawai K, Oyasu R, and Akaza H
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- Animals, Compliance, Male, Models, Animal, Omentum pathology, Swine, Time Factors, Urinary Bladder pathology, Collagen, Omentum surgery, Plastic Surgery Procedures methods, Regeneration physiology, Regenerative Medicine methods, Urinary Bladder drug effects, Urinary Bladder surgery
- Abstract
Objective: We present our experience with a novel bladder reconstruction model using a collagen sponge pre-embedded within the omentum. The aim of the study is to evaluate tissue regeneration of the reconstructed bladder and the effect of prefabricating the collagen patch within the omentum., Materials and Methods: Twenty pigs were divided into three groups. For the prefabricated patch group (PFP; n=10), collagen sponge was inserted into the omentum. After 1 week, the pigs underwent a hemicystectomy and the sponge with an attached omental flap was brought to close the defect. For the non-prefabricated patch group (NPFP; n=6), pigs received hemicystectomy and closure with a collagen sponge without prefabricating in the omentum. Four other pigs received hemicystectomy alone as a control (C; n=4). All animals in the NPFP and C groups, and 7 of 10 in the PFP group were sacrificed at 4 or 8 weeks. Three other pigs in the PFP group were sacrificed at 12 weeks. Resected bladders were submitted to hematoxylin-eosin, and immunohistochemical staining., Results: All animals except for two in the NPFP group survived. At the time of grafting, the collagen sponge was covered with thick omental methothelial layers, and neo-vascularization from the omentum was observed. At each time point, only slight adhesion was observed around the patch in the PFP group, while severe adhesion between the patch and the bowel was observed in the NPFP group, suggesting that prefabricated collagen sponge within the omentum prevented urine leakage from the bladder. Histologically, the patch was well vascularized, and the luminal surface was covered with urothelium at 4 weeks in both groups. However, in the PFP group, there was mild inflammation in the submucosa and in-growth of smooth muscle derived from the adjacent muscle layers was observed with time, whereas severe inflammation was observed and in-growth of smooth muscle was limited in the NPF group., Conclusions: Prefabricating of a collagen patch within the omentum stimulated early neo-vascularization before grafting, and this procedure appears to offer an advantage for bladder reconstruction over a non-prefabricated procedure in terms of prevention of urine leakage and inflammation, and favorable tissue regeneration.
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- 2006
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26. Chemopreventive effects of cyclooxygenase-2 inhibitor and epidermal growth factor-receptor kinase inhibitor on rat urinary bladder carcinogenesis.
- Author
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Hattori K, Iida K, Joraku A, Tsukamoto S, Akaza H, and Oyasu R
- Subjects
- Animals, Anticarcinogenic Agents adverse effects, Butylhydroxybutylnitrosamine, Carcinogens, Carcinoma, Transitional Cell chemically induced, Carcinoma, Transitional Cell pathology, Carcinoma, Transitional Cell prevention & control, Cyclooxygenase Inhibitors adverse effects, Gefitinib, Male, Meloxicam, Protein Kinase Inhibitors adverse effects, Quinazolines adverse effects, Rats, Rats, Inbred F344, Thiazines adverse effects, Thiazoles adverse effects, Treatment Outcome, Urinary Bladder Neoplasms chemically induced, Urinary Bladder Neoplasms pathology, Anticarcinogenic Agents administration & dosage, Cyclooxygenase Inhibitors administration & dosage, Protein Kinase Inhibitors administration & dosage, Quinazolines administration & dosage, Thiazines administration & dosage, Thiazoles administration & dosage, Urinary Bladder Neoplasms prevention & control
- Abstract
Objective: To examine the chemopreventive effects of a selective cyclooxygenase (COX)-2 inhibitor, meloxicam, and a selective epidermal growth factor (EGF)-receptor tyrosine kinase inhibitor, gefitinib (as a single agent) on a carcinogen-induced rodent bladder carcinogenesis model., Materials and Methods: The study comprised 103 male Fisher-344 rats (8 weeks old); after initial carcinogen treatment for 8 weeks with 0.05%N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in drinking water, the rats were divided into five groups, i.e. group 1, control (vehicle only); group 2, gefitinib high-dose (15 mg/kg by gavage once daily); group 3, gefitinib low-dose (5 mg/kg); group 4, meloxicam high-dose (1.8 mg/kg by gavage once daily); and group 5, meloxicam low-dose (0.6 mg/kg). Twelve weeks later the rats were killed; after fixing the bladder in 10% formalin, the number and size of hyperplasia and carcinoma foci were recorded microscopically in sections stained with haematoxylin and eosin, submitted entirely as multiple strips., Results: The incidence of carcinoma, confirmed microscopically, was: control 14/20 (70%); high-dose gefitinib, 7/20 (35%); low-dose gefitinib, 7/20 (35%); high-dose meloxicam 7/21 (33%); and low-dose meloxicam, 12/20 (60%). The mean numbers of carcinomas per bladder in groups 1-5 were 1.2, 0.5, 0.4, 0.5 and 1.1, respectively. The incidence and the mean number of carcinomas per bladder were significantly lower in the treatment groups (P < 0.05) than in the control group, except in the low-dose meloxicam group. There were no significant adverse effects., Conclusion: Both meloxicam and gefitinib have inhibitory effects on rat bladder carcinogenesis with no significant adverse effects. A combination of these drugs would be worth studying for their synergistic effects.
- Published
- 2006
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27. Nrf2 is essential for the chemopreventive efficacy of oltipraz against urinary bladder carcinogenesis.
- Author
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Iida K, Itoh K, Kumagai Y, Oyasu R, Hattori K, Kawai K, Shimazui T, Akaza H, and Yamamoto M
- Subjects
- Animals, Butylhydroxybutylnitrosamine pharmacokinetics, Carcinogens pharmacokinetics, DNA-Binding Proteins deficiency, DNA-Binding Proteins genetics, Enzyme Induction drug effects, Female, Gene Expression drug effects, Genetic Predisposition to Disease, Glucuronides metabolism, Glucuronosyltransferase antagonists & inhibitors, Glucuronosyltransferase biosynthesis, Glucuronosyltransferase genetics, Glucuronosyltransferase metabolism, Inactivation, Metabolic, Male, Mice, Mice, Inbred C57BL, Mice, Inbred ICR, Mice, Knockout, Microsomes, Liver drug effects, Microsomes, Liver enzymology, Microsomes, Liver metabolism, NF-E2-Related Factor 2, Thiones, Thiophenes, Trans-Activators deficiency, Trans-Activators genetics, Urinary Bladder drug effects, Urinary Bladder enzymology, Urinary Bladder metabolism, Urinary Bladder Neoplasms chemically induced, Urinary Bladder Neoplasms genetics, Urinary Bladder Neoplasms metabolism, Anticarcinogenic Agents pharmacology, DNA-Binding Proteins physiology, Pyrazines pharmacology, Trans-Activators physiology, Urinary Bladder Neoplasms prevention & control
- Abstract
The induction of phase 2 detoxifying enzymes, such as UDP-glucuronosyltransferases (UGTs), in response to an array of naturally occurring and synthetic agents, such as oltipraz (4-methyl-5-[2-pyrazinyl]-1,2-dithiole-3-thione), provides an effective means of protection against a variety of carcinogens. Transcription factor Nrf2 is an essential regulator of the inducible expression of detoxifying enzyme genes by chemopreventive agents. In this study, we investigated in Nrf2-deficient mice the susceptibility to the urinary bladder-specific carcinogen N-nitrosobutyl(4-hydroxybutyl)amine (BBN) and the chemopreventive efficacy of oltipraz. The incidence of urinary bladder carcinoma by BBN was significantly higher in Nrf2-/- mice than in wild-type mice; invasive carcinoma was found in 24.0 and 38.5% of wild-type and Nrf2-/- mice, respectively. Oltipraz induced the phase 2 enzymes responsible for BBN detoxification in the liver and urinary bladder in an Nrf2-dependent manner. As expected, therefore, oltipraz decreased the incidence of urinary bladder carcinoma by BBN in wild-type mice but had little effect in Nrf2-/- mice. In wild-type mouse liver, oltipraz significantly induced BBN glucuronidation and decreased the urinary concentration of N-nitrosobutyl(3-carboxypropyl)amine, a proximate carcinogen of BBN. Importantly, BBN was found to suppress the expression of UGT1A specifically in the urinary bladder. This suppression was counteracted by oltipraz in wild-type mice but not in Nrf2-/- mice. These results show that Nrf2 and its downstream target genes are responsible for BBN detoxification. Furthermore, oltipraz prevents carcinogenesis by BBN by enhancing detoxification of this carcinogen in the liver and urinary bladder.
- Published
- 2004
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28. Phenotypic switch from paracrine to autocrine role of hepatocyte growth factor in an androgen-independent human prostatic carcinoma cell line, CWR22R.
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Nakashiro K, Hara S, Shinohara Y, Oyasu M, Kawamata H, Shintani S, Hamakawa H, and Oyasu R
- Subjects
- Animals, Disease Progression, Drug Resistance, Neoplasm, Hepatocyte Growth Factor antagonists & inhibitors, Hepatocyte Growth Factor genetics, Humans, Male, Mice, Mice, Transgenic, Neoplasms, Hormone-Dependent genetics, Neoplasms, Hormone-Dependent pathology, Phenotype, Prostate metabolism, Prostate pathology, Prostatic Neoplasms genetics, Prostatic Neoplasms pathology, Proto-Oncogene Proteins c-met antagonists & inhibitors, Proto-Oncogene Proteins c-met genetics, RNA Interference, Stromal Cells metabolism, Stromal Cells pathology, Transplantation, Heterologous, Tumor Cells, Cultured, Androgens physiology, Autocrine Communication, Hepatocyte Growth Factor metabolism, Neoplasms, Hormone-Dependent metabolism, Paracrine Communication, Prostatic Neoplasms metabolism
- Abstract
Support mechanisms involved in growth of androgen-independent prostate cancer are primarily unknown. Hepatocyte growth factor (HGF)/Met has been suggested to be one of them based primarily on immunohistochemical studies. We conducted a series of experiments to assess the role of the HGF/Met system in an androgen-dependent human prostate carcinoma, CWR22 and its androgen-independent derivative, CWR22R. We found that action of HGF changed from paracrine to autocrine in progression to androgen-independent state. CWR22 tumors did not express HGF but expressed Met, whereas prostate stromal cells expressed HGF at a high level. Growth of CWR22 was stimulated either by addition of HGF to the culture or by the presence of prostate stromal cells. On the other hand, CWR22R cells expressed both HGF and Met. Knockdown of Met expression by RNA interference method suppressed the growth of CWR22R cells. Our data suggest that HGF is intimately involved in growth of human prostate cancer and that progression from the androgen-dependent to the androgen-independent state is associated with an adaptive switch in support mechanism from paracrine to autocrine. Our data offer one mechanism to account for androgen-independent human cancer growth.
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- 2004
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29. Immunohistochemical expression of hepatocyte growth factor and c-Met/HGF receptor in benign and malignant human prostate tissue.
- Author
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Nakashiro K, Hayashi Y, and Oyasu R
- Subjects
- Cell Line, Tumor, Hormones therapeutic use, Humans, Immunohistochemistry, Male, Neoplasm Metastasis, Prostatic Intraepithelial Neoplasia metabolism, Hepatocyte Growth Factor biosynthesis, Prostate metabolism, Prostatic Neoplasms metabolism, Proto-Oncogene Proteins c-met biosynthesis
- Abstract
Hepatocyte growth factor (HGF) has been proposed to be an autocrine/paracrine growth factor for carcinomas of various organs. We recently demonstrated that HGF produced by prostate-derived stromal cells was a paracrine growth factor that stimulated the growth of androgen-independent prostate cancer cells in vitro and in vivo. To assess possible involvement of HGF in prostate cancer, we examined the immunohistochemical expression and localization of HGF and c-Met/HGF receptor in benign and malignant human prostate tissues. In benign glands, columnar cells generally were negative for c-Met, but basal cells were stained uniformly at a high level. In high-grade prostatic intraepithelial neoplasia (PIN) and carcinoma, more than 50% of these foci were stained uniformly. There was no difference in the frequency of positively stained cells by Gleason score. The prostate stroma stained diffusely for HGF, and the staining intensity varied depending upon the amounts of smooth-muscle cells that were stained more intensely than the connective-tissue matrix. A great majority of benign columnar cells were negative for HGF whereas high-grade PIN and carcinoma foci stained focally for HGF. Hormonal ablation therapy prior to prostatectomy did not seem to alter the expression of HGF/c-Met in carcinoma cells. These results indicate that, as the degree of neoplasia progresses, epithelial cells begin to express c-Met protein, that PIN and carcinoma may have developed a c-Met-HGF paracrine loop with the stroma, and that in some carcinoma foci an autocrine loop may operate with HGF expressed by carcinoma cells themselves.
- Published
- 2003
30. Malignant lymphoma of bronchus-associated lymphoid tissue (BALT) coexistent with pulmonary tuberculosis.
- Author
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Inadome Y, Ikezawa T, Oyasu R, and Noguchi M
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- Aged, Antigens, CD20 analysis, Epithelioid Cells microbiology, Epithelioid Cells pathology, Gene Rearrangement, Granuloma microbiology, Granuloma pathology, Humans, Immunoglobulin Heavy Chains genetics, Lymphoid Tissue metabolism, Lymphoid Tissue pathology, Lymphoma, B-Cell, Marginal Zone pathology, Male, Mycobacterium tuberculosis isolation & purification, Polymerase Chain Reaction, Tomography, X-Ray Computed, Tuberculosis, Pulmonary diagnostic imaging, Tuberculosis, Pulmonary pathology, Bronchi pathology, Lymphoma, B-Cell, Marginal Zone complications, Tuberculosis, Pulmonary complications
- Abstract
A case in which malignant lymphoma occurred in association with a tuberculosis focus in a 70-year-old man is reported. Surrounding the epithelioid cell granulomas with caseous necrosis was a dense and diffuse monotonous infiltration of atypical lymphoid cells. Acid-fast bacilli were found in the granulomas and pulmonary tuberculosis was diagnosed. The infiltrating atypical lymphoid cells occasionally invaded the respiratory epithelium producing lymphoepithelial lesions. Immunohistochemically, the lymphoid cells were positive for CD20, and clonal rearrangement of the immunoglobulin heavy chain gene was demonstrated by polymerase chain reaction (PCR). We diagnosed the lesion as a pulmonary malignant lymphoma of bronchus-associated lymphoid tissue (BALT) occurring in the background of tuberculosis. This is the first reported case of pulmonary BALT lymphoma coexistent with pulmonary tuberculosis.
- Published
- 2001
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31. Role of peroxisome proliferator-activated receptor gamma and its ligands in non-neoplastic and neoplastic human urothelial cells.
- Author
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Nakashiro KI, Hayashi Y, Kita A, Tamatani T, Chlenski A, Usuda N, Hattori K, Reddy JK, and Oyasu R
- Subjects
- Aged, Blotting, Western, Cell Division drug effects, Cell Line, Chromans pharmacology, Dose-Response Relationship, Drug, Humans, Immunologic Factors pharmacology, Ligands, Male, Pioglitazone, Prostaglandin D2 analogs & derivatives, RNA, Messenger analysis, Receptors, Cytoplasmic and Nuclear drug effects, Receptors, Cytoplasmic and Nuclear genetics, Reverse Transcriptase Polymerase Chain Reaction, Thiazoles pharmacology, Transcription Factors drug effects, Transcription Factors genetics, Transfection, Troglitazone, Tumor Cells, Cultured, Urinary Bladder Neoplasms pathology, Urothelium cytology, Urothelium pathology, Prostaglandin D2 pharmacology, Receptors, Cytoplasmic and Nuclear physiology, Thiazolidinediones, Transcription Factors physiology, Transcription, Genetic, Urinary Bladder Neoplasms genetics, Urothelium physiology
- Abstract
Peroxisome proliferator-activated receptor gamma (PPARgamma) is a member of the nuclear receptor superfamily of ligand-activated transcription factors and is expressed in several types of tissue. Although PPARgamma reportedly is expressed in normal urothelium, its function is unknown. We examined the expression of PPARgamma in normal urothelium and bladder cancer in an attempt to assess its functional role. Immunohistochemical staining revealed normal urothelium to express PPARgamma uniformly. All low-grade carcinomas were positive either diffusely or focally, whereas staining was primarily focal or absent in high-grade carcinomas. A nonneoplastic urothelial cell line (1T-1), a low-grade (RT4) carcinoma cell line, and two high-grade (T24 and 253J) carcinoma cell lines in culture expressed PPARgamma mRNA and protein. Luciferase assay indicated that PPARgamma was functional. PPARgamma ligands (15-deoxy-Delta(12,14)-prostaglandin J(2), troglitazone and pioglitazone) suppressed the growth of nonneoplastic and neoplastic urothelial cells in a dose-dependent manner. However, neoplastic cells were more resistant than were nonneoplastic cells. Failure to express PPARgamma or ineffective transcriptional activity may be some of the mechanisms responsible for resistance to the inhibitory action of PPARgamma ligands.
- Published
- 2001
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32. Androgen receptor expression in androgen-independent prostate cancer cell lines.
- Author
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Chlenski A, Nakashiro K, Ketels KV, Korovaitseva GI, and Oyasu R
- Subjects
- Androgens pharmacology, Animals, DNA Methylation, DNA Mutational Analysis, DNA, Neoplasm metabolism, Humans, Male, Mice, Mice, Nude, Promoter Regions, Genetic, Transcription, Genetic, Tumor Cells, Cultured, Adenocarcinoma, Gene Expression Regulation, Neoplastic, Prostatic Neoplasms, Receptors, Androgen genetics
- Abstract
Background: Almost all attempts at establishing prostate carcinoma cell lines have resulted in generation of cells that are androgen-independent, including commonly used LNCaP which expresses androgen receptor (AR) and AR-negative Du145 and PC-3. We attempted to clarify the mechanism(s) responsible for the failure to respond to androgen., Methods: Cell lines LNCaP, CWR22R, PC-3, Du145, and CA7T2CL were used to examine the AR promoter function with a reporter gene assay and its methylation status by Southern blot, PCR of bisulfite-converted DNA, and 5-aza-2'-deoxycytidine treatment. Structural abnormalities of the AR were identified by sequencing of reverse-transcribed mRNA., Results: All tested AR-positive prostate carcinoma cells were capable of AR transcription at a significantly higher level than PC-3 and Du145, thus suggesting relative deficiency of the transcription factors in the AR-negative cells, further associated with methylation. Examination of CWR22R cells, which express the AR but are androgen-independent, identified an in-frame duplication of exon 3, which resulted in insertion of 39 amino acids in the DNA-binding domain., Conclusions: Relative deficiency of transcription factors associated with methylation is responsible for the lack of AR promoter function in most of AR-negative cell lines. Mutations in the AR gene are present in the cells that express the AR but are androgen-independent.
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- 2001
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33. Organization and expression of the human zo-2 gene (tjp-2) in normal and neoplastic tissues.
- Author
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Chlenski A, Ketels KV, Korovaitseva GI, Talamonti MS, Oyasu R, and Scarpelli DG
- Subjects
- Exons, Introns, Membrane Proteins biosynthesis, Molecular Sequence Data, Protein Isoforms biosynthesis, Tumor Cells, Cultured, Zonula Occludens-2 Protein, Gene Expression Regulation, Neoplastic, Membrane Proteins genetics
- Abstract
One of the tight junction components, zonula occludens protein 2 (ZO-2), is expressed as two isoforms, ZO-2A and ZO-2C, in normal epithelia. In pancreatic adenocarcinoma of the ductal type ZO-2A is absent, but none of the common mechanisms of gene inactivation is responsible for lack of ZO-2A expression. In the current study, we report the complete organization of the human zo-2 gene (tjp-2), its alternative splicing, and its expression in normal and neoplastic tissues of several organ sites. In addition to pancreatic adenocarcinoma, ZO-2 was found to be de-regulated in breast adenocarcinoma, but not in colon or prostate adenocarcinoma. The latter are considered to be of acinar rather than ductal type. Thus, our data indicate the importance of zo-2 (tjp-2) gene regulation in ductal cancer development and should help to understand the defects of intercellular interactions, critical for suppressing the malignant phenotype.
- Published
- 2000
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34. Hepatocyte growth factor secreted by prostate-derived stromal cells stimulates growth of androgen-independent human prostatic carcinoma cells.
- Author
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Nakashiro K, Okamoto M, Hayashi Y, and Oyasu R
- Subjects
- Adenocarcinoma metabolism, Animals, Antibodies, Blocking pharmacology, Bone Marrow Cells physiology, Coculture Techniques, Culture Media, Conditioned, Growth Inhibitors pharmacology, Growth Inhibitors physiology, Humans, Male, Mice, Mice, Nude, Neoplasm Transplantation, Prostate drug effects, Prostatic Neoplasms metabolism, Skin cytology, Skin metabolism, Stromal Cells metabolism, Transplantation, Heterologous, Tumor Cells, Cultured, Adenocarcinoma pathology, Hepatocyte Growth Factor physiology, Prostate physiology, Prostatic Neoplasms pathology, Stromal Cells physiology
- Abstract
The objective of the present study is to examine the role of prostate stromal cells on growth and progression of prostate cancer. Co-inoculation of androgen-independent carcinoma cells (PC-3 and CA-7T2) with prostate-derived stromal (P-ST) cells significantly enhanced the growth of carcinoma cells in athymic nude mice. For the in vitro study, a three-dimensional co-culture system was used. It consisted of two layers of collagen gel. Stromal cells were suspended in the lower layer, whereas cancer cells were suspended in the upper layer. Compared to the control culture, the presence of P-ST cells in the lower collagen layer significantly stimulated the growth of carcinoma cells. Such an effect was not demonstrated when carcinoma cells were co-cultured with either bone marrow-derived or skin-derived stromal cells. We identified hepatocyte growth factor (HGF) as the principal growth factor released by P-ST cells but not by bone marrow-derived or skin-derived stromal cells. Neutralizing antibodies against HGF completely abrogated the stimulatory effect of P-ST cells. Exogenous HGF likewise stimulated the growth of carcinoma cells in vitro and in vivo. These results suggest that HGF produced by P-ST cells is a paracrine growth factor that stimulates the growth of androgen-independent prostate cancer cell lines.
- Published
- 2000
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35. zo-2 gene alternative promoters in normal and neoplastic human pancreatic duct cells.
- Author
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Chlenski A, Ketels KV, Engeriser JL, Talamonti MS, Tsao MS, Koutnikova H, Oyasu R, and Scarpelli DG
- Subjects
- Base Sequence, DNA Methylation, Humans, Molecular Sequence Data, Reverse Transcriptase Polymerase Chain Reaction, Tumor Cells, Cultured, Zonula Occludens-2 Protein, Membrane Proteins genetics, Pancreatic Ducts metabolism, Pancreatic Neoplasms genetics, Promoter Regions, Genetic
- Abstract
We have observed that 2 forms of zonula occludens 2 (ZO-2) protein, ZO-2A and ZO-2C, are expressed in normal human pancreatic duct cells, but only ZO-2C in pancreatic duct adenocarcinoma. We report here partial organization of the zo-2 gene. Transcription of 2 forms of ZO-2 mRNA is driven by alternative promoters P(A) and P(C). Lack of expression of ZO-2A in neoplastic cells is caused by inactivation of the downstream promoter P(A). Analysis of the promoter P(A) sequence and function in normal and neoplastic cells demonstrated that neither structural changes (mutations) nor a change in the pool of transcription factors is responsible for its inactivation. Although hypermethylation was found in a large number of cancer clones, treatment with 5-aza-2'-deoxycytidine did not fully cause the promoter function to recover. We conclude that the initial down-regulation of zo-2 promoter P(A) activity in pancreatic duct carcinomas is due to the structural or functional alteration(s) in the regulatory elements, localized outside the analyzed promoter region. Methylation of P(A) is responsible for the inactivation of the suppressed promoter at the late stages of tumor development., (Copyright 1999 Wiley-Liss, Inc.)
- Published
- 1999
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36. Neoplastic conversion of human urothelial cells in vitro by overexpression of H2O2-generating peroxisomal fatty acyl CoA oxidase.
- Author
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Tamatani T, Hattori K, Nakashiro K, Hayashi Y, Wu S, Klumpp D, Reddy JK, and Oyasu R
- Subjects
- Acyl-CoA Oxidase, Aged, Animals, Blotting, Northern, Blotting, Western, Carcinoma, Squamous Cell pathology, Cell Division drug effects, Cell Transformation, Neoplastic metabolism, Cells, Cultured, Humans, Hydrogen Peroxide adverse effects, Karyotyping, Linoleic Acid pharmacology, Male, Matrix Metalloproteinase 2 metabolism, Matrix Metalloproteinase 9 metabolism, Mice, Mice, Inbred BALB C, Mice, Nude, Neoplasm Transplantation, Oxidoreductases genetics, Rats, Transfection, Urothelium cytology, Urothelium drug effects, Carcinoma, Squamous Cell chemically induced, Cell Transformation, Neoplastic chemically induced, Hydrogen Peroxide metabolism, Oxidoreductases biosynthesis, Peroxisomes enzymology, Urothelium enzymology
- Abstract
An in vitro study was conducted to determine if malignant transformation can be induced in human urothelial cells immortalized with human papillomavirus E6/E7 genes. A clone designated 1T1 was isolated and then stably transfected with an acyl CoA oxidase (ACOX)-expression construct. The cells generated H2O2 in a large quantity from the substrate linoleic acid (LA). After 56 days of LA treatment, cells persistently formed an epithelial cyst in athymic nude mice with an occasional intracystic epithelial nodule. Our results indicate that human urothelial cells can be transformed to low grade neoplastic cells by H2O2 and suggest that H2O2 may be involved in the development of bladder cancer.
- Published
- 1999
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37. Tumorigenic conversion of a rat urothelial cell line by human polymorphonuclear leukocytes activated by lipopolysaccharide.
- Author
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Tamatani T, Turk P, Weitzman S, and Oyasu R
- Subjects
- 8-Hydroxy-2'-Deoxyguanosine, Animals, Catalase pharmacology, Cell Line, Cell Transformation, Neoplastic drug effects, Cell Transformation, Neoplastic genetics, Cell Transformation, Neoplastic immunology, Deoxyguanosine analogs & derivatives, Deoxyguanosine biosynthesis, Diffusion Chambers, Culture, Genes, p53 genetics, Genes, ras genetics, Humans, Hydrogen Peroxide metabolism, Lymphocyte Activation, Mice, Mice, Nude, Neoplasm Transplantation, Neutrophils drug effects, Neutrophils immunology, Rats, Tumor Stem Cell Assay, Urothelium drug effects, Urothelium metabolism, Vitamin E pharmacology, Cell Transformation, Neoplastic metabolism, Lipopolysaccharides pharmacology, Neutrophils metabolism, Urothelium pathology
- Abstract
Chronic inflammation is a significant risk factor for the development of urinary bladder cancer. We have shown that inflammation induced by killed Escherichia coli and also by its lipopolysaccharide (LPS) strikingly enhances N-methyl-N-nitrosourea (MNU)-initiated rat bladder carcinogenesis. Aspirates from the bladder lumen contained a large quantity of hydrogen peroxide (H2O2) and several cytokines. In this study, we tested the hypothesis that reactive oxygen intermediates (ROI) released from activated polymorphonuclear leukocytes (PMN) are involved in inflammation-associated bladder carcinogenesis. Using an immortalized nontumorigenic rat urothelial cell line, MYP3, we examined the effect of LPS-activated PMN on malignant transformation. MYP3 cells pretreated with or without MNU were exposed daily to LPS-activated PMN for one week and were then tested for growth in soft agar. In contrast to no colony formation by the parental cells, a varying number of colonies developed from cells treated with LPS-activated PMN. Although combined treatment with MNU and PMN was most effective (P<0.01), cells treated with LPS-activated PMN alone also formed a small number of colonies. Addition of catalase, which decomposes H2O2, and/or an antioxidant, alpha-tocopherol, reduced the number of colonies induced by LPS-activated PMN (P<0.05). Cells derived from colonies were tumorigenic in athymic nude mice. However, tumorigenicity in mice was greater with cells treated with both MNU and PMN than with cells treated with PMN alone. Our results suggest that ROI released from LPS-activated PMN may be one of the mechanisms involved in the carcinogenesis associated with active urinary tract infection.
- Published
- 1999
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38. Tight junction protein ZO-2 is differentially expressed in normal pancreatic ducts compared to human pancreatic adenocarcinoma.
- Author
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Chlenski A, Ketels KV, Tsao MS, Talamonti MS, Anderson MR, Oyasu R, and Scarpelli DG
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Blotting, Northern, Blotting, Western, Cricetinae, Humans, Immunohistochemistry, Membrane Proteins analysis, Molecular Sequence Data, RNA, Messenger analysis, Reverse Transcriptase Polymerase Chain Reaction, Zonula Occludens-2 Protein, Adenocarcinoma metabolism, Membrane Proteins genetics, Pancreatic Ducts metabolism, Pancreatic Neoplasms metabolism
- Abstract
Differential display of hamster mRNA identified a fragment present in normal pancreatic duct cells that is not expressed in pancreatic duct carcinoma cells. Sequence analysis showed an 88% and 82% identity, respectively, to the cDNA of the canine and human tight junction zo-2 gene. Semi-quantitative RT-PCR analysis of human ZO-2 revealed a striking difference in the expression of various regions of the ZO-2 transcript in normal and neoplastic cells and the presence of an abnormality at the 5'-end of mRNA. RACE analysis identified 2 human ZO-2 mRNAs that encode proteins of different lengths, designated as ZO-2A and ZO-2C. The difference between the 2 forms of ZO-2 is the absence of 23 amino acid residues at the N terminus of ZO-2C compared with ZO-2A. Although ZO-2C was expressed in normal pancreatic cells and a majority of neoplastic tissues analyzed, ZO-2A was undetectable except in one case in all of the pancreatic adenocarcinomas analyzed. This suggests the presence of a yet to be identified motif important for cell-growth regulation within the 23-amino acid residue N-terminal peptide of ZO-2A, MPVRGDRGFPPRRELSGWLRAPG.
- Published
- 1999
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39. The usefulness of touch preparation cytological evaluation and prostatic capsule involvement in prediction of prostate cancer recurrence.
- Author
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Brannigan RE, Shin E, Rademaker A, Oyasu R, Huang CF, Pearle MS, and McVary KT
- Subjects
- Aged, Cytological Techniques, Follow-Up Studies, Humans, Male, Middle Aged, Neoplasm Invasiveness, Neoplasm Recurrence, Local epidemiology, Neoplasm Staging, Predictive Value of Tests, Prospective Studies, Prostatectomy, Prostatic Neoplasms surgery, Neoplasm Recurrence, Local pathology, Prostatic Neoplasms pathology
- Abstract
Purpose: Touch preparation cytology has been used in oncology as a technique to assist in predicting local tumor recurrence. We prospectively investigated the relationship between this cytological evaluation and the standard histological method of assessing specimens, measuring the distance from the tumor to the various anatomical boundaries and disease recurrence in radical retropubic prostatectomy patients., Materials and Methods: In a prospective study of 91 consecutive clinical stages T1c and T2 cancer cases radical retropubic prostatectomy touch preparation cytology was performed intraoperatively in an anatomical fashion (apex, posterior, lateral right and left, and base). A single blinded cytopathologist reviewed all prostate touch preparation specimens and categorized them as malignant, benign or atypical cells. Benign or atypical cells were classified as negative cytology. Detailed histological margin analysis of the surgical specimens was also done in which distances between the tumor front, and prostate capsule (inner and outer edge) and surgical margins (apex, posterior, right and left lateral, and base) were measured. All specimens were re-staged by the same pathologist. Median followup was 38 months. Disease recurrence was determined biochemically (prostate specific antigen), and with bone scans, prostatic fossa biopsies and digital rectal examinations., Results: Of the 91 specimens 25 were excluded from study because distance measurements could not be made for technical reasons. Multivariate analysis was performed on the remaining 66 patients based on the variables of stage, age, cytology status, distance from tumor to the inner prostatic capsule, distance from tumor to the surgical margin and postoperative Gleason sum. The only variable with independent prognostic value was postoperative Gleason sum (p = 0.04). Cytology status was not statistically significant (p = 0.07) nor were distance data to the inner capsule (p >0.05) and surgical margin (p >0.05)., Conclusions: Although touch preparation cytology does not enhance prognostic information already provided by Gleason sum, it does correlate highly with postoperative Gleason sum. Other gross macroscopic variables, that is pathological stage, margin status and distance measurements, although lacking in independent predictive value, correlated with postoperative Gleason sum. The constancy of Gleason sum leads us to believe that the key to predicting prostatic cancer behavior lies not on the macroscopic but on the molecular or cellular level. Of the various factors analyzed in this study postoperative Gleason sum remains the most powerful predictor of recurrence risk.
- Published
- 1998
40. Exogenous epidermal growth factor exerts promoting action during the early phase of rat urinary bladder carcinogenesis.
- Author
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Hattori K, Fujimoto K, Tamatani T, Rademaker A, and Oyasu R
- Subjects
- Animals, Carcinoma, Transitional Cell pathology, Male, Methylnitrosourea, Neoplasm Invasiveness, Rats, Rats, Inbred F344, Time Factors, Urinary Bladder Neoplasms pathology, Carcinogens toxicity, Carcinoma, Transitional Cell chemically induced, Epidermal Growth Factor toxicity, Urinary Bladder Neoplasms chemically induced
- Abstract
Using the heterotopically transplanted rat urinary bladder (HTB) model that was developed in our laboratory, we examined the relationship between the duration of epidermal growth factor (EGF) treatment and acquisition of EGF-independence of urinary bladder tumors that were induced by EGF stimulation. After treatment with N-methyl-N-nitrosourea (MNU) (0.25 mg/0.5 ml of 0.9% NaCl once a week for 3 consecutive weeks), animals at week 3 received EGF [250 ng/0.5 ml phosphate-buffered saline (PBS)] into the HTBs once a week for 20, 28, or 36 weeks. For examination of the effect of EGF withdrawal, one half of the rats received the vehicle (PBS) only beginning at week 23 or week 31 for 8 weeks. When animals were examined at week 23, the incidence and the mean number of tumors per bladder were low, irrespective of EGF treatment. In the bladders that had been exposed to EGF during the first 20 weeks after MNU administration, however, both the incidence and the mean number of tumors per bladder had increased significantly at week 31, regardless of whether or not EGF treatment was continued beyond week 23. Between weeks 31 and 39, EGF treatment demonstrated no effect; both the incidence of tumors and the mean number of tumors were the same as those at week 31. These results suggest that EGF exerts its promoting effect only during the early phase of MNU-initiated bladder carcinogenesis, but that its effect becomes manifest during the subsequent 8 weeks. EGF independence may be due to establishment of an autocrine growth-stimulatory mechanism in bladder tumors.
- Published
- 1998
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41. Loss of expression of transforming growth factor-beta receptors is associated with poor prognosis in prostate cancer patients.
- Author
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Kim IY, Ahn HJ, Lang S, Oefelein MG, Oyasu R, Kozlowski JM, and Lee C
- Subjects
- Humans, Male, Neoplasm Staging, Prognosis, Prostate metabolism, Prostatic Neoplasms mortality, Survival Rate, Neoplasm Proteins metabolism, Prostatic Neoplasms metabolism, Prostatic Neoplasms pathology, Receptors, Transforming Growth Factor beta metabolism
- Abstract
Transforming growth factor beta (TGF-beta) is a potent inhibitor of proliferation in most cells and exerts its effects through an interaction with membrane receptors type I (TGF-betaRI) and type II (TGF-betaRII). Recently, we have demonstrated a correlation between the loss of expression of TGF-betaRI and TGF-betaRII and increasing Gleason score in archival human prostate cancer tissues. To evaluate the potential prognostic value of this observation, the present study investigated the expression of TGF-beta receptors in association with disease progression after the initial diagnosis in 52 archival human prostate cancer tissues. The expression of both TGF-betaRI and TGF-betaRII was correlated with the Gleason score, clinical tumor stage, 4-year survival rate, and serological recurrence rate after radical prostatectomy. Results revealed that there was a significant association between the Gleason score and the loss of expression of TGF-betaRI (P < 0.025) and TGF-betaRII (P < 0.01). However, only the loss of TGF-betaRI expression showed a statistically significant association with the clinical tumor stage (P < 0.05), 4-year survival rate (P < 0.05), and serological recurrence rate after radical prostatectomy (P < 0.025). Therefore, these data indicate that the loss of TGF-betaRI expression as measured by immunohistochemical staining may be a potential prognostic marker in prostate cancer patients.
- Published
- 1998
42. Interleukin-6 and epidermal growth factor promote anchorage-independent growth of immortalized human prostatic epithelial cells treated with N-methyl-N-nitrosourea.
- Author
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Okamoto M, Webber MM, Quader S, and Oyasu R
- Subjects
- Cell Adhesion, Cell Culture Techniques methods, Cell Division drug effects, Cell Line, Epithelial Cells cytology, Epithelial Cells physiology, Humans, Kinetics, Male, Prostate cytology, Prostate physiology, Receptors, Interleukin-6 analysis, Receptors, Interleukin-6 biosynthesis, Time Factors, Cell Transformation, Neoplastic, Epidermal Growth Factor pharmacology, Epithelial Cells drug effects, Interleukin-6 pharmacology, Methylnitrosourea toxicity, Prostate drug effects
- Abstract
Background: Epidermal growth factor (EGF) and interleukin (IL)-6 are implicated in the growth of benign and malignant prostatic epithelial cells. We investigated the role of EGF and IL-6 during the process of prostate carcinogenesis., Methods: Using growth in soft agar as an index of transformation, we examined the effect of EGF and IL-6 on the enhancement of N-methyl-N-nitrosourea (MNU)-initiated transformation of immortalized, nontumorigenic prostatic epithelial cell lines (PWR-1E and RWPE-1) developed in our laboratory. The effect of EGF and IL-6 on the growth of MNU-induced transformants isolated from soft agar was assessed both in monolayer culture and in a soft agar., Results: After a 1 hr exposure to N-methyl-N-nitrosourea (50 microg/ml), cells (5 x 10(4)) were grown in soft agar in the presence of EGF (5 ng/ml) or IL-6 (10 or 100 ng/ml). Addition of EGF or IL-6 significantly increased colony formation in soft agar of both immortalized prostatic epithelial cell lines initiated with MNU (P < 0.001-0.05). Only a very small number of colonies was observed with the parental cell lines PWR-1E and RWPE-1 not exposed to MNU, and their numbers increased by the addition of EGF or IL-6. All of the transformants, derived by exposure to MNU and isolated from soft agar, exhibited a higher cell growth potential in monolayer cultures than did their parental cell lines. Furthermore, as compared to the parental cell lines, growth response of MNU-transformants to 5alpha-dihydrotestosterone (5alpha-DHT), EGF, or IL-6 in monolayer culture was better in 5 of 8, 6 of 8, and 7 of 8 cell lines, respectively. All of the MNU-transformants exhibited a far higher colony-forming efficiency in soft agar than did the parental cell lines. However, the degree of responsiveness to EGF or IL-6 in soft agar varied among the MNU-transformants., Conclusions: The results of the present study suggest that IL-6 and EGF may enhance prostate carcinogenesis in vitro by preferentially stimulating the growth of transformed cells.
- Published
- 1998
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43. Comparison of tunica albuginea substitutes for the treatment of Peyronie's disease.
- Author
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Brannigan RE, Kim ED, Oyasu R, and McVary KT
- Subjects
- Animals, Disease Models, Animal, Dogs, Fibrosis, Male, Penile Induration pathology, Penis pathology, Implants, Experimental, Penile Induration surgery, Penis surgery
- Abstract
Purpose: Peyronie's disease is a connective tissue disorder resulting in fibrotic plaque formation on the tunica albuginea of the penis. One approach to repair consists of plaque excision and patching with one of many potential patch materials. Because the optimal patch material for covering the resultant defect has not been determined, this study compares histological and cavernosometric changes in the penis as a result of the placement of three different types of patch grafts used in surgery for Peyronie's disease., Materials and Methods: Eleven mongrel dogs were divided into three groups, each receiving a different patch material (superficial dorsal penile vein, silicone fabric, and dermabraded preputial flap). Each dog had dynamic infusion cavernosometry (DIC) performed prior to placement of the patch over a 6 x 3 mm. defect surgically created in the tunica albuginea. Three months later, DIC was repeated prior to sacrifice. Histology of the penis was examined using Masson's trichrome, and hematoxylin and eosin stains., Results: The only difference among the cavernosometric parameters (preop versus postop) was a higher initial pressure in the dermabraded preputial flap group postoperatively. The dogs undergoing vein patch had moderate fibrosis with apparent reformation of the tunica albuginea over the patch site. The normal venous architecture of the graft was no longer recognizable. Those dogs receiving a silicone patch had moderate fibrosis with a fibrous sheath of compressed histiocytes and fibroblasts enveloping the graft site. Finally, the dermabraded preputial flap patch group had mild-moderate fibrosis with focal loss of the cavernosal space underlying the flap., Conclusions: We feel that continued use of the vein patch for repair of Peyronie's disease is warranted.
- Published
- 1998
44. Blastomycosis of the epididymis and prostate.
- Author
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Seo R, Oyasu R, and Schaeffer A
- Subjects
- Adult, Antifungal Agents administration & dosage, Blastomycosis drug therapy, Blastomycosis pathology, Humans, Ketoconazole administration & dosage, Male, Necrosis, Prostate pathology, Prostatic Diseases drug therapy, Prostatic Diseases pathology, Testicular Diseases diagnosis, Testicular Diseases drug therapy, Testicular Diseases pathology, Blastomycosis diagnosis, Epididymis pathology, Prostatic Diseases diagnosis
- Abstract
We report a case of blastomycosis presenting as epididymitis and prostatitis. The diagnosis was suggested by pathologic findings in the prostate and epididymis and was further supported by serology. The diagnosis was confirmed by culture and special staining. Long-term cure was accomplished after a 12-month course of oral ketoconazole (400 mg/day). Therapy was monitored by culture and serology. Blastomycosis is an unusual but significant pathogen which occasionally presents with genitourinary tract involvement. Effective diagnostic and oral treatment regimens are now available but are dependent on a high degree of suspicion in cases of chronic prostatitis or epididymitis.
- Published
- 1997
- Full Text
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45. Autocrine effect of androgen on proliferation of an androgen responsive prostatic carcinoma cell line, LNCAP: role of interleukin-6.
- Author
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Okamoto M, Lee C, and Oyasu R
- Subjects
- Antibodies immunology, Carcinoma metabolism, Cell Division drug effects, Dihydrotestosterone pharmacology, Dose-Response Relationship, Drug, Humans, Interleukin-6 immunology, Interleukin-6 metabolism, Male, Prostatic Neoplasms metabolism, Tumor Cells, Cultured drug effects, Androgens pharmacology, Carcinoma pathology, Interleukin-6 physiology, Prostatic Neoplasms pathology
- Abstract
LNCaP is an androgen-responsive prostatic carcinoma cell line that exhibits a bell-shaped growth response curve to increasing doses of dihydrotestosterone (DHT) in culture. Although the precise mechanism responsible for this unique growth response to androgen stimulation remains unclear, many studies have suggested that androgen modulates the level of various growth factors. In an early study, we demonstrated that LNCaP proliferation was stimulated by interleukin (IL)-6 in a paracrine manner, because these cells did not express a significant amount of IL-6. In the present study, the role of IL-6 in mediating androgen regulated proliferation in LNCaP cells was investigated. DHT, at increasing doses up to 10(-8) M, resulted in a release of IL-6 from LNCaP cells. This dose-dependent effect of DHT on LNCaP proliferation could be partially inhibited by the addition of antibody against IL-6 into the culture medium. These results indicate that the DHT-induced expression of IL-6 stimulates proliferation of LNCaP cells in culture in an autocrine manner.
- Published
- 1997
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46. Intracellular levels of SGP-2 (Clusterin) correlate with tumor grade in prostate cancer.
- Author
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Steinberg J, Oyasu R, Lang S, Sintich S, Rademaker A, Lee C, Kozlowski JM, and Sensibar JA
- Subjects
- Adenocarcinoma chemistry, Adenocarcinoma surgery, Apoptosis, Biopsy, Carcinoma in Situ chemistry, Carcinoma in Situ pathology, Carcinoma in Situ surgery, Clusterin, Densitometry, Humans, Immunoenzyme Techniques, Male, Neoplasm Invasiveness, Prostatectomy, Prostatic Hyperplasia metabolism, Prostatic Hyperplasia pathology, Prostatic Neoplasms chemistry, Prostatic Neoplasms surgery, Adenocarcinoma pathology, Biomarkers, Tumor analysis, Glycoproteins analysis, Molecular Chaperones, Neoplasm Proteins analysis, Prostatic Neoplasms pathology
- Abstract
Our previous observations in LNCaP cells in vitro demonstrated an association between apoptotic cell death resistance and SGP-2 (Clusterin) overexpression. Accordingly, we hypothesized that high levels of cellular SGP-2 would aid in identifying biologically aggressive prostate cancer cells with unique survival advantages. To test this hypothesis, 40 archival radical prostatectomy and/or biopsy specimens of varying grades of prostate cancer were subjected to immunohistochemical SGP-2 staining. The resulting epithelial stains were quantified subjectively on a scale of 1-3 by four independent observers. Benign prostatic epithelial cells from young donors served as controls and showed a consistently weak staining intensity. In contrast, prostate cancer specimens showed varying degrees of staining intensity that correlated with a Gleason pattern (P = 0.006). This correlation supports the hypothesis that protection from apoptotic death may account, in part, for biologically aggressive tumor behavior.
- Published
- 1997
47. One core positive prostate biopsy is a poor predictor of cancer volume in the radical prostatectomy specimen.
- Author
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Wang X, Brannigan RE, Rademaker AW, McVary KT, and Oyasu R
- Subjects
- Adenocarcinoma blood, Biopsy, Humans, Male, Predictive Value of Tests, Prostate-Specific Antigen blood, Prostatic Neoplasms blood, Adenocarcinoma pathology, Adenocarcinoma surgery, Prostatectomy, Prostatic Neoplasms pathology, Prostatic Neoplasms surgery
- Abstract
Purpose: In view of the recent increase in patients presenting with only 1 core positive for prostate carcinoma, we examined the correlation in tumor volume between the biopsy and the subsequent radical prostatectomy specimen., Materials and Methods: We studied a total of 169 consecutive prostate biopsies with matched radical prostatectomy specimens and selected 48 patients with only 1 positive core., Results: Cancers found in the biopsy regardless of their size were associated with a wide range of cancer volume in the radical prostatectomy specimens, and the amount of cancer in the biopsy was a poor predictor of the volume of cancer in the prostatectomy specimen. Even with a cancer of 3 mm. or less in the biopsy, 57% of patients had cancer of clinically significant volume (greater than 0.5 ml.). Other modalities for the evaluation of prostate cancer such as Gleason score and clinical stage were not helpful in segregating patients with clinically significant from those with insignificant volume of cancer. However, when combined with a preoperative serum prostate-specific antigen higher than 10 ng./ml., 1 core positive biopsy could reliably predict the presence of cancer of significant volume., Conclusions: One core only positive prostate biopsy, when accompanied by an elevated serum prostate specific antigen value (greater than 10 ng./ml.), strongly suggests the presence of clinically significant cancer.
- Published
- 1997
48. Transformation in vitro of a nontumorigenic rat urothelial cell line by tumor necrosis factor-alpha.
- Author
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Okamoto M and Oyasu R
- Subjects
- Animals, Cell Line, Hydrogen Peroxide toxicity, Male, Methylnitrosourea toxicity, Mice, Mice, Inbred BALB C, Mice, Nude, Rats, Vitamin E pharmacology, Cell Transformation, Neoplastic, Tumor Necrosis Factor-alpha toxicity
- Abstract
Chronic inflammation is a significant risk factor for the development of urinary bladder cancer. We showed previously that inflammation induced by killed Escherichia coli strikingly enhanced N-methyl-N-nitrosourea (MNU)-initiated rat bladder carcinogenesis. We also demonstrated a marked increase in several cytokines, including TNF-alpha, in aspirates from bladders treated with killed E. coli. In the present investigation, we tested the hypothesis that TNF-alpha released during inflammation was causally related to the development of bladder cancer. Using growth in soft agar and tumorigenicity in athymic nude mice as indices of transformation, we examined the effect of TNF-alpha on the enhancement of H2O2-initiated transformation of MYP3 cells; MYP3 is an anchorage-dependent nontumorigenic rat urothelial cell line. We have already demonstrated that H2O2 is a potent transforming agent which is released during the inflammatory process. MYP3 cells pretreated with H2O2 were exposed to TNF-alpha (0 to 100 ng/ml) for 1 week in monolayer culture and were then subjected to growth in soft agar. A marked increase in the number of colonies was observed in the cells that were first treated with H2O2 and subsequently exposed to TNF-alpha, as compared with the untreated control (p < 0.001). In addition, treatment with TNF-alpha alone caused colony formation and was associated with a 6.5- to 8.7-fold increase in intracellular H2O2 (p < 0.001). Addition of an antioxidant, alpha-tocopherol, resulted in a significant reduction in the number of colonies induced by TNF-alpha (p < 0.001). The transformants induced by TNF-alpha have acquired the potential of anchorage-independent growth and tumorigenicity in athymic nude mice. Our results suggest that TNF-alpha-induced transformation in urothelial cells is due to induction of H2O2, and that this may be one of the mechanisms involved in the carcinogenesis in vivo associated with chronic urinary tract infection.
- Published
- 1997
49. Overexpression of transforming growth factor beta type I receptor abolishes malignant phenotype of a rat bladder carcinoma cell line.
- Author
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Okamoto M and Oyasu R
- Subjects
- Animals, Carcinoma genetics, Carcinoma metabolism, Cell Division, Gene Expression, Humans, Mice, Mice, Nude, Neoplasms, Experimental pathology, Phenotype, Protein Serine-Threonine Kinases genetics, RNA, Messenger analysis, RNA, Neoplasm analysis, Rats, Receptor, Transforming Growth Factor-beta Type I, Receptors, Transforming Growth Factor beta genetics, Transfection, Transforming Growth Factor beta metabolism, Transforming Growth Factor beta pharmacology, Tumor Cells, Cultured, Urinary Bladder Neoplasms genetics, Urinary Bladder Neoplasms metabolism, Activin Receptors, Type I, Carcinoma pathology, Protein Serine-Threonine Kinases physiology, Receptors, Transforming Growth Factor beta physiology, Urinary Bladder Neoplasms pathology
- Abstract
Transforming growth factor beta1 (TGF-beta1), a potent growth inhibitor of bladder carcinoma cells, elicits its effects by binding to cell surface receptors. LMC19, a highly invasive and metastatic rat bladder carcinoma cell line, was insensitive to the growth-suppressive effect of TGF-beta1, and it expressed undetectable levels of TGF-beta type I receptor (TbetaRI) mRNA by reverse transcription-PCR and its protein by Western blot analysis. To evaluate the effect of TbetaRI in reducing the malignant phenotype, we transfected LMC19 with an expression vector containing human TbetaRI cDNA. Stable transfection with the expression vector yielded five transfectants that expressed the introduced TbetaRI mRNA. The binding activity of TGF-beta1 to TbetaRI was restored in all of the transfectants. The growth of the transfectants on a plastic surface was markedly inhibited in the presence of TGF-beta1 in the culture medium (P < 0.001), whereas the control cells (parental and transfectant with only neo gene) remained TGF-beta1 insensitive. The colony-forming efficiency of the transfectants was strongly reduced in soft agar medium containing 5% FCS (P < 0.001) and was restored by the addition of a neutralizing anti-TGF-beta antibody. Furthermore, none of the transfectants tested formed tumors in athymic nude mice, whereas the control cells did so in all mice tested. These findings indicate that introduction of TbetaRI can revert a malignant phenotype to a less aggressive (even benign) phenotype in a rat bladder carcinoma cell line that lacks TbetaRI, and that reduced expression of TbetaRI may be associated with the development and progression of bladder carcinomas.
- Published
- 1997
50. Interleukin-6 functions as an autocrine growth factor in human bladder carcinoma cell lines in vitro.
- Author
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Okamoto M, Hattori K, and Oyasu R
- Subjects
- Antibodies, Blocking pharmacology, Antigens, CD metabolism, Cell Division drug effects, Cytokine Receptor gp130, Growth Substances physiology, Humans, Interleukin-6 genetics, Interleukin-6 pharmacology, Membrane Glycoproteins metabolism, Oligonucleotides, Antisense pharmacology, RNA, Messenger analysis, Receptors, Interleukin metabolism, Signal Transduction, Tumor Cells, Cultured, Urinary Bladder metabolism, Interleukin-6 physiology, Urinary Bladder Neoplasms metabolism
- Abstract
Interleukin (IL)-6 is reported to function as a growth factor for renal and prostatic carcinomas. We conducted the present study to define the role of IL-6 in the growth of normal and neoplastic urothelial cells. Human bladder carcinoma cell lines (253J, RT4 and T24) and primary cultured human urothelial cells derived from normal ureters were used. Recombinant human IL-6 stimulated the growth of bladder carcinoma cell lines far better than that of normal urothelial cells (p < 0.001). All carcinoma cell lines tested produced and released IL-6, whereas normal urothelial cells did so only at marginal levels. Furthermore, treatment with lipopolysaccharide derived from Escherichia coli, tumor necrosis factor-alpha or IL-1 increased IL-6 secretion by bladder carcinoma cell lines but not by normal urothelial cells. Growth of bladder carcinoma cells was significantly inhibited by anti-IL-6 neutralizing antibody or the anti-sense oligonucleotide for IL-6 cDNA. We conclude that IL-6 functions as an autocrine growth factor for bladder carcinoma cells but not for normal urothelial cells and that it may be a factor accounting for the marked enhancement of inflammation-associated bladder carcinogenesis and tumor growth.
- Published
- 1997
- Full Text
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