N-buty1-N-(4-hydroxybutyl)nitrosamine(BBN) is known to have a strong. specific carcinogenic action on the urinary bladder of rats. Rat bladder lesions induced by BBN are very similar to those of Pusan histopathologically. To investigate the surface change in the urinary bladder epithelium induced by 0.05% BBN scanning electron microscopic examination was done. Normal bladder epithelium was formed by relatively uniform sized. flat polygonal cells and clearly defined with intercellular ridges. in high magnification, the luminal surface of superficial cell consisted of hexagona1 areas and concave plaques between microridge giving a honeycomb appearance but no microvilli was visible. On BBN administration for 12 weeks, the superficial cells varied in size and shape and covered by numerous uniform round microvilli forming cobble stone appearance. On BBN administration for 12 weeks and water for 6 weeks, the superficial cells were covered with numerous microvilli completely. In some areas numerous pleomorphic microvilli were seen. Although pleomorphic microvilli are not a specific marker for neoplastic transformation, their presence is an indicator. of a markedly abnormal proliferative response.
Animals ; Busan ; Butylhydroxybutylnitrosamine* ; Epithelium* ; Microscopy, Electron, Scanning ; Microvilli ; Phenobarbital ; Rats* ; Urinary Bladder* ; Water

BACKGROUND: Survivin belongs to the inhibitor of apoptosis family, and it has recently been found to be expressed in most solid tumors. Therefore, its expression is suggested to have prognostic significance. However, no data are available concerning the significance of survivin for the carcinogenesis of bladder cancer. METHODS: In order to induce urothelial tumor in the rat urinary bladder, 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) was administered to male Sprague-Dawley rats for 30 weeks. We used immunohistochemistry to investigate the expressions of survivin, HSP90, Bcl-2 and Bax in rat bladder carcinogenesis. RESULTS: Urothelial cell hyperplasia, papilloma, non-invasive urothelial carcinoma and invasive urothelial carcinoma appeared at 5, 10, 20 and 30 weeks, respectively. The expressions of survivin and HSP90 increased sequentially from normal mucosa, hyperplasia, papilloma, non-invasive urothelial carcinoma to invasive urothelial carcinoma. The expressions of Bcl-2 and Bax did not increase, however the number of cases with more than 1 of Bcl-2/Bax expression ratio increased sequentially during the progression of urothelial lesion. The expression of survivin showed a statistically significant correlation with the expression of HSP90 and the Bcl-2/Bax expression ratio. CONCLUSIONS: Our findings suggest that survivin may be involved in the carcinogenesis of rat bladder and its expression is correlated with the expression of HSP90 and the Bcl-2/Bax expression ratio.
Animals ; Apoptosis ; bcl-2-Associated X Protein* ; Butylhydroxybutylnitrosamine ; Carcinogenesis* ; Humans ; Hyperplasia ; Immunohistochemistry ; Male ; Mucous Membrane ; Papilloma ; Rats* ; Rats, Sprague-Dawley ; Urinary Bladder Neoplasms ; Urinary Bladder*

PURPOSE: Cyclooxygenase (COX)-2 plays an important role in promoting cancer cell proliferation and angiogenesis in human bladder cancer. In this study, we investigated the antitumor or antiangiogenic effects of selective COX-2 inhibitor on N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)-induced rat bladder tumorigenesis. MATERIALS AND METHODS: Forty male Fischer 344 rats (control) were given only 0.05% BBN, while 40 rats (experimental) were administered 1,500mg/ kg celecoxib once daily and this treatment started from 1 week before their BBN treatment. Ten rats from the control groups and the experimental groups were then sacrificed at 4, 12, 16 and 24 weeks after BBN treatment. We observed all the bladders macroscopically as well as microscopically, and we measured the COX-2 expression in the bladder tissues. Utilizing a cDNA microarray, we analyzed the significant differences of gene expression between the 12 week-control group and the 12 week-experimental group. RESULTS: The incidence of tumor was lower in the experimental group than in the control group from week 12 to week 24. The COX-2 expressions were more significantly decreased via the BBN induction (p<0.05) in the experimental groups than in the control groups after 4 weeks. For the 12 week-experimental group, there were 15 genes altered by the administration of selective COX-2 inhibitor, and the selective COX-2 inhibitor especially regulated transgelin, membrane metallo endopeptidase and apolipoprotein E of these 15 genes to prevent the incidence of bladder tumor. CONCLUSIONS: Selective COX-2 inhibitor has an inhibitory effect on BBN-induced rat bladder tumorigenesis. In the pre-neoplastic phase, selective COX-2 inhibitor regulates transgelin, membrane metallo endopeptidase and apolipoprotein E to prevent the incidence of bladder tumor.
Angiogenesis Inducing Agents ; Animals ; Apolipoproteins ; Butylhydroxybutylnitrosamine ; Carcinogenesis ; Cell Proliferation ; Cyclooxygenase 2* ; Gene Expression* ; Humans ; Incidence ; Male ; Neprilysin ; Oligonucleotide Array Sequence Analysis ; Prostaglandin-Endoperoxide Synthases ; Rats* ; Transcriptome* ; Urinary Bladder Neoplasms* ; Urinary Bladder* ; Celecoxib

PURPOSE: Cyclooxygenase-2 (COX-2) plays an important role in promoting cancer cell proliferation and angiogenesis in human bladder cancer. The selective COX-2 inhibitor has antitumor activities in vivo and in vitro in a variety of tumor types. In this study, the antitumor or antiangiogenic effects of selective COX-2 inhibitor on N-butyl-N-(4-hydroxybutyl)nitrosamine-induced rat bladder tumorigenesis were investigated. MATERIALS AND METHODS: Forty male Fischer 344 rats (Control group) were given only 0.05% BBN in water ad libitum, while 40 others (Experimental group) were administered 1,500mug/kg celecoxib once daily through the gavage tube, which started 1 week before the BBN treatment. Ten rats were used as the normal bladder. Ten rats from the control and experimental group were sacrificed 4, 12, 16, and 24 weeks after the start of the BBN treatment. All bladders were evaluated both macroscopically and microscopically. We also measured COX-2 expression, microvessel density (MVD), and vascular endothelial growth factor (VEGF) protein concentrations in the bladder tissues. RESULTS: Macroscopically and microscopically, the incidence of tumor was lower in the experimental group than in the control group from the 12th week to the 24th week. Each incidence of tumor in week 12, week 16, and week 24 was 20%, 50%, and 80% in the control group and 0%, 20%, and 40% in the experimental group, respectively. In both the control and experimental groups, COX-2 expression had a tendency to be concentrated in the cytoplasm of the epithelial cells of the papillary tumor and the endothelial cells adjacent to the vessel the basal layer of bladder. COX-2 and VEGF expression were significantly more decreased in the experimental groups than in the control groups after 4 weeks from the BBN induction (p<0.05). MVD was significantly decreased in the experimental group at week 16 (p<0.05). CONCLUSIONS: The selective COX-2 inhibitor has an inhibitory effect on BBN-induced rat bladder tumorigenesis because of its partially antiangiogenic properties. In the future, the selective COX-2 inhibitor could be expected to play an important role as a chemo-preventive agent and as therapeutic aids in bladder cancer if these inhibitory effects can be reproduced in human bladder tumorigenesis.
Angiogenesis Inducing Agents ; Animals ; Butylhydroxybutylnitrosamine ; Carcinogenesis* ; Cell Proliferation ; Cyclooxygenase 2* ; Cytoplasm ; Endothelial Cells ; Epithelial Cells ; Humans ; Incidence ; Male ; Microvessels ; Rats* ; Urinary Bladder Neoplasms* ; Urinary Bladder* ; Vascular Endothelial Growth Factor A ; von Willebrand Factor ; Water ; Celecoxib

It is known that the activity of tumor cells correlates with the malignant potential of tumors. Nucleolar organizer regions(NORs) are loops of DNA which occur in nucleoli and which possess ribosomal DNA genes. Ribosomal DNA genes transcribe to ribosomal RNA by RNA polymerase I and are of vital significance in the ultimate synthesis of protein. Proteins associated with the NORs are stained with silver nitrate(Ag-NORs). Ag-NORs were studied in various tumors and might reflect the activity of cells and might be and indicator of the degree of malignancy in tumors. 0.05 % N-Butyl-N(4-hydroxybutyl) nitrosamine(BBN) in drinking water was given for 8 and 14 weeks to induce pre-neoplastic and neoplastic vesical epithelial lesions in female Wister rats. Ag-NORs were stained by the simple one-step silver colloid staining in routine processed, formalin-fixed paraffin sections of bladder lesions induced by N-butyl-N(4-hydroxybutyl) nitrosamine(BBN) in rat. The mean number of silver stained NORs(Ag-NORs) was as follows : normal transitional epithelium was 1.64+/-0.25(mean+/-SD; n=10), simple hyperplasia was 2.24+/-0.24(n=7). nodular hyperplasia was 2.63+/-0.12 (n=6), transitional cell papilloma was 3.24+/-0.28(n=6) and transitional cell carcinoma was 4.52+/-0.32(n=10). Based on the above results, we concluded that the mean number of Ag-NORs showed a stepwise increase from normal transitional epithelium through simple hyperplasia and nodular hyperplasia to papilloma and carcinoma of bladder epithelium induced by BBN in rat and may reflect proliferative activity of cells. Further investigations may be needed to confirm whether the number or quantification of Ag-NORs is a useful method for evaluating proliferative activity of neoplastic lesions or another indicator of prognosis in human bladder cancer.
Animals ; Butylhydroxybutylnitrosamine* ; Carcinoma, Transitional Cell ; Colloids ; DNA ; DNA, Ribosomal ; Drinking Water ; Epithelium ; Female ; Humans ; Hyperplasia ; Nucleolus Organizer Region* ; Papilloma ; Paraffin ; Prognosis ; Rats* ; RNA Polymerase I ; RNA, Ribosomal ; Silver ; Urinary Bladder Neoplasms ; Urinary Bladder*

This study was aimed to establish rat bladder tumor animal models to investigate the in viva antitumor effect of polyanhydride-pirarubicin (PAD-THP), a long-lasting anti-cancer implant, in the bladder tumor of animal models. The model of bladder cancer was set up with N-butly-N-(4 hydroxybutyl) nitrosamine (BBN) feeding into rats. The PAD-THP long-acting anti-cancer implants containing the drugs and the same dose of the THP naked drug were placed under the bladder mucosa of bladder tumor model in vivo. The pirarubicin plasma concentration was measured with high performance liquid chromatography (HPLC) detection in vivo. The effective drug concentration and lasting period were observed and compared in the animal bodies. The tumor sizes were measured before and after the treatment. The in viva antitumor effects were analyzed and compared. The results showed that more significant antitumor effect of PAD-THP implants on the local drug release characteristics were presented compared with that of the same dose of THP bare drug group and there were significant differences (P<0. 05) between the two methods. All the results indicated that the PAD-THP anti-cancer implants in the postoperative local treatment of bladder tumors would show prosperous in the future for clinical application.
Animals ; Antineoplastic Agents ; administration & dosage ; Butylhydroxybutylnitrosamine ; Delayed-Action Preparations ; administration & dosage ; Disease Models, Animal ; Doxorubicin ; administration & dosage ; analogs & derivatives ; Female ; Implants, Experimental ; Polyanhydrides ; administration & dosage ; Rats ; Rats, Sprague-Dawley ; Urinary Bladder Neoplasms ; chemically induced ; drug therapy ; pathology