PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Butylhydroxybutylnitrosamine”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources

Preferential gene transfer to BBN-induced rat bladder tumor by simple instillation of adenoviral vector.

OBJECTIVES: We examined the efficacy and safety of intravesical instillation of adenoviral vectors to develop gene therapy protocols for bladder cancer. In this study, an adenoviral vector containing the beta-galactosidase gene was instilled into the rat bladder with N-butyl-N-(4-hydroxybutyl) nitrosamine-induced tumors. We evaluated the effect of the glycosaminoglycan (GAG) layer on adenoviral transduction of bladder urothelium. In addition, we determined the systemic distribution of the adenoviral vector after instillation. METHODS: An adenoviral vector containing either the beta-galactosidase or the herpes simplex virus thymidine kinase gene was transurethrally instilled into the bladder, after which efficacy of gene transfer was evaluated by staining with 5-bromo-4-chloro-3-indolyl-beta-D-galactopyraminoside, and the distribution of the gene was examined by reverse transcriptase-polymerase chain reaction. To determine the extent to which the GAG layer may have inhibited gene transfer by the adenoviral vector, prior to instillation of adenoviral vector, normal bladders were pretreated with either phosphate-buffered saline or HCl, which would destroy the mucosal GAG layer. RESULTS: We found that intravesical instillation of an adenoviral vector caused preferential gene transfer to the tumor cells and that expression of the transferred gene occurred exclusively in the bladder. Removing the GAG layer rendered the normal bladder highly susceptible to adenoviral gene transfer, indicating that GAG on normal mucosa prevented adenoviral gene transfer. CONCLUSIONS: BBN-induced bladder tumors were preferentially transduced by instillation of adenoviral vectors probably due to the lack of GAG layers on their surface. Intravesical instillation of adenoviral vectors does not result in systemic infection. These results encourage the consideration of gene therapy in the treatment of human bladder cancer.

Adenoviridae↗

Lack of promotion of urinary bladder carcinogenesis by sodium bicarbonate and/or L-ascorbic acid in male ODS/Shi-od/od rats synthesizing alpha 2 mu-globulin but not L-ascorbic acid.

The study was designed to investigate whether sodium bicarbonate (NaHCO3) and/or L-ascorbic acid (AsA) promote urinary bladder carcinogenesis in male ODS/Shi-od/od (ODS) rats, which, unlike male F344 rats, are resistant to sodium L-ascorbate (Na-AsA)-promoting effects. Whereas F344 rats can synthesize AsA and alpha 2 mu-globulin (A2 mu-G), only A2 mu-G in produced in ODS rats. The two strains were given 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in their drinking water for 2 wk and then were fed basal CA-1 diet supplemented with 3% NaHCO3 plus 5% AsA (NaHCO3 + AsA), 3% NaHCO3, 5% AsA, or no chemicals for 32 wk. ODS rats given BBN-NaHCO3 or BBN-(NaHCO3 + AsA) had only a few small carcinomas in the urinary bladder, like those receiving BBN alone or BBN-AsA. In contrast, F344 rats administered BBN-NaHCO3 or BBN-(NaHCO3 + AsA) had many more, larger, carcinoma than animals of the same strain given BBN alone or BBN-AsA. AsA alone did not have any effect in either strain. Administration of NaHCO3 alone or NaHCO3 + AsA was associated with significant elevation of urinary pH and Na+ concentration to the same extent in both strains but, again, AsA alone was without effect. NaHCO3 + AsA and AsA alone increased the urinary concentration of total ascorbic acid in both strains but the observed levels wer lower in ODS rats. The results indicate that ODS rats are resistant to the modifying effects of NaHCO3 and/or AsA on two-stage urinary bladder carcinogenesis, and thus that the susceptibility to the promotional activity of sodium-salt-type compounds may be regulated by factors other than A2 mu-G-synthesizing ability and urinary levels of pH, Na+ and total ascorbic acid.

Animals↗

Lymphoproliferative response and T lymphocyte subsets in a medium-term multi-organ bioassay for carcinogenesis in Wistar rats.

The lymphoproliferative response and T lymphocyte subsets were evaluated at different stages of carcinogenesis in male Wistar rats sequentially initiated with N-diethylnitrosamine (DEN), N-butyl-N-4(hydroxybutyl)nitrosamine (BBN), N-methyl-N-nitrosourea (MNU), dihydroxy-di-N-propylnitrosamine (DHPN) and N, N'-dimethylhydrazine (DMH) (DMBDD initiation). One group was evaluated at the 4th week and other initiated group at the 30th week. Two initiated groups were also exposed through diet to 2-acetylaminofluorene (2-AAF) or phenobarbital (PB), from the 6th until the 30th week. Two groups received only 2-AAF or PB until the 30th week. Five groups were studied to evaluate the effects of each initiator. The lymphoproliferative response was induced in vitro by concanavalin A and the percentage of T lymphocyte subsets was determined by flow cytometry. All groups submitted to initiation only, initiation plus promotion, or promotion only, developed significantly more preneoplastic lesions than the untreated control group. The main target organs for tumor development were the liver, colon, urinary bladder, kidneys and Zymbal glands, mainly in the group treated with DMBDD+2-AAF. There were no alterations of the lymphoproliferative response and of the T lymphocyte subsets percentage in the DMBDD-treated group at the 4th and 30th weeks. At the 30th week, the T lymphocyte subsets percentage was also not affected in the initiated groups after treatments with 2-AAF or PB. The lymphoproliferative response, however, was decreased in the DMBDD+2-AAF group and in the groups treated only with 2-AAF or PB. The present results indicate that the initiating chemicals used in the DMBDD initiation protocol do not exert any influence on the immune system. The alteration of lymphoproliferative response induced at the advanced stage of carcinogenesis without alteration of T lymphocyte subsets may indicate that the influence of 2-AAF and PB on the immune system is functional and not toxic.

1,2-Dimethylhydrazine↗

Site-dependent modulating effects of conjugated fatty acids from safflower oil in a rat two-stage carcinogenesis model in female Sprague-Dawley rats.

Modifying effects of dietary administration of conjugated fatty acids from safflower oil (CFA-S), rich in conjugated linoleic acid, on major organs were examined in the post-initiation stage of a two-stage carcinogenesis model in female rats. Groups of 21 or 22 F344 female rats were treated sequentially with 2,2'-dihydroxy-di-n-propylnitosamine (intragastrically, i.g.), 7,12-dimethylbenz[a]anthracene (i.g.), 1,2-dimethylhydrazine (subcutaneously) and N-butyl-N-(4-hydroxybutyl)nitrosamine (in drinking water) during the first 3 weeks for initiation, and then administered diet containing 1 or 0.1% CFA-S for 33 weeks. Further groups of animals were treated with carcinogens or 1% CFA-S alone, or maintained as non-treated controls. All surviving animals were killed at week 36, and major organs were examined histopathologically for development of pre-neoplastic and neoplastic lesions. The 1 and 0.1% CFA-S treatment significantly decreased the incidence and multiplicity of mammary carcinomas, though a clear dose response was not observed. In the urinary bladder, the incidence of papillary or nodular hyperplasia but not tumors was significantly increased in the 1% CFA-S-treated group. The results indicate that low dose CFA-S may find application as a potent chemopreventor of mammary carcinogenesis.

1,2-Dimethylhydrazine↗

Inhibitory effects of 2-mercaptoethane sulfonate and 6-phenylhexyl isothiocyanate on urinary bladder tumorigenesis in rats induced by N-butyl-N-(4-hydroxybutyl)nitrosamine.

The effects of 2-mercaptoethane sulfonate (MESNA) and phenethyl and 6-phenylhexyl isothiocyanates (PEITC and PHITC) on urinary bladder tumorigenesis were investigated in Wistar rats treated with N-butyl-N-(4-hydroxybutyl)nitrosamine (BHBN). A total of 190 male rats were divided into eight groups. Animals in groups 1, 3 and 4 were administered BHBN in drinking water (0.025%) and group 2 rats were given 0.025% BHBN plus 0.05% MESNA solution for 15 weeks. Rats in groups 3 and 4 were fed a diet supplemented with PEITC or PHITC at a dose level of 0.5 micromol/g for 16 weeks starting 1 week prior to the BHBN treatment. Rats in groups 5-7 served as MESNA, PEITC or PHITC alone controls. Group 8 served as a non-treatment control. The chromatographic profile of drinking water for group 2 animals indicated no chemical interaction between BHBN and MESNA. The incidences of papillomas in the bladder and total bladder tumors including transitional cell carcinomas were significantly (P<0.01) reduced in group 2 as compared to that in group 1. The multiplicities of papillomas or total bladder tumors were significantly (P<0.01) lower in group 2 and 4 rats treated with MESNA and PHITC, respectively, than in group 1 rats. The PEITC treatment, however, did not affect the BHBN-induced bladder tumorigenesis. No bladder tumors were found in animals of groups 5-8. The results in the present study clearly indicate that both MESNA and PHITC are potent chemopreventive agents against bladder tumor development in rats induced by BHBN.

Animals↗

Chemoprevention of lung carcinogenesis by cacao liquor proanthocyanidins in a male rat multi-organ carcinogenesis model.

The effects of cacao liquor proanthocyanidins (CLPr) on tumorigenesis were investigated using a multi-organ carcinogenesis model in male F344 rats receiving combined treatment with a single i.p. injection of diethylnitrosamine (100 mg/kg body wt), four i.p. injections of N-methylnitrosourea (20 mg/kg body wt), four s.c. injections of dimethylhydrazine (40 mg/kg body wt), along with 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine and then 0.1% 2,2'-dihydroxy-di-n-propylnitrosamine, both in the drinking water, for 2 weeks each, during the initial 4-week period (DMBDD treatment). Starting 1 week thereafter, rats were administered CLPr at a dose of 0.025% or 0.25% and the experiment was terminated at week 36. The final survival rate for the DMBDD+0.25% CLPr group was significantly greater than for the DMBDD alone group. In the lung, significant reduction in the incidence and multiplicity of carcinomas was also observed, and in the thyroid, quantitative values for adenomas also tended to decrease in a CLPr dose-dependent manner. No significant modification in the small intestine, colon or kidney was evident. These results indicate that CLPr exerts chemopreventive effects in the lung without any promoting influence in other major organs.

1,2-Dimethylhydrazine↗

Concanavalin A agglutination of bladder cells of rats treated with bladder carcinogens; a rapid new test to detect bladder carcinogens.

N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN), which is a potent, specific bladder carcinogen in rats, and its related compounds were orally administered to rats for 1 week. The bladder cells were isolated by the treatment with EDTA and sonication and they were subjected to agglutination assay by concanavalin A (Con A). Bladder cells obtained from rats treated with BBN, N-butyl-N-(3-carboxypropyl)nitrosamine (BCPN), N-ethyl-N-(4-hydroxybutyl)nitrosamine (EHBN) and N-butyl-N-(2-hydroxyethyl)nitrosamine (BHEN) were agglutination-positive, while those cells treated with N-tert-butyl-N-(4-hydroxybutyl)-nitrosamine (t-BBH) and N-butyl-N-(3-hydroxypropyl)nitrosamine (BHPN) were negative. Results obtained by this method were highly correlated with the known carcinogenicity of BBN and its analogues. Therefore, this method could be used for rapid screening of bladder carcinogens.

Animals↗

p53 gene mutation in N-butyl-N-(4-hydroxybutyl)nitrosamine-induced urinary bladder tumors and N-methyl-N-nitrosourea-induced colon tumors of rats.

We analyzed p53 mutations in 17 N-butyl-N-(4-hydroxybutyl) nitrosamine-induced bladder transitional cell carcinomas (TCCs) with or without areas of squamous cell carcinoma (SCC) of Long-Evans Cinnamon (LEC) and F344 rats, and in 7 N-methyl-N-nitrosourea-induced colon adenocarcinomas of LEC rats by polymerase chain reaction-single strand conformation polymorphism analysis and DNA sequencing. Of these bladder tumors, one TCC with moderately differentiated SCC had a T to G transversion mutation at codon 141, leading to a Val to Gly amino acid change. No p53 mutation was found in colon adenocarcinomas. Thus a p53 gene mutation seems infrequent in these rat bladder and colon carcinogenesis models even in the late stage.

Animals↗

Infrequent involvement of microsatellite instability in urinary bladder carcinomas of the NON/Shi mouse treated with N-butyl-N-(4-hydroxybutyl)nitrosamine.

Variation in the frequency of microsatellite instability (MSI) has been reported in different kinds of human malignant tumors, with less than one-third of invasive urinary bladder carcinoma cases estimated to be affected. Here we investigated the MSI for 27 microsatellite sequences in invasive urinary bladder carcinomas of the NON/Shi mouse induced by N-butyl-N-(4-hydroxybutyl)nitrosamine. A total of 28 urinary bladder carcinomas of both transitional cell and squamous cell types were studied. All were invasive (greater than pT3) and high-grade and 10 of them had metastasis. Only two (11%) of 18 primary bladder carcinomas without metastasis foci showed alterations in one or two loci. None of 10 pairs of urinary bladder carcinomas and metastasis foci demonstrated any alterations. In conclusion, MSI which represents a defect in the DNA mismatch repair system is infrequent and therefore unlikely to be a critical step in genesis of invasive mouse urinary bladder carcinomas.

Animals↗

Lack of involvement of p53 gene mutations in N-methyl-N-nitrosourea-induced bladder tumor progression in N-butyl-N-(4-hydroxybutyl)nitrosamine-treated rats and no suppression by indomethacin.

The relevance of p53 mutations to rat bladder cancer progression induced by a single injection of N-methyl-N-nitrosourea (MNU) and the chemopreventive effects of indomethacin (IM) were investigated in male F344 rats, initially given N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) at a dose of 500 ppm in the drinking water for 10 weeks. The animals were subsequently treated with a single intraperitoneal injection of MNU at a dose of 50 mg/kg b.w. at week 20. A subgroup was then given IM dissolved in the drinking water at a concentration of 20 ppm for 20 weeks. The experiment was terminated at week 40 when transitional cell carcinomas (TCC) were observed in all animals given BBN, regardless of the administration of MNU and/or IM (incidences ranged from 80 to 100%). The extent of invasion was significantly greater with the additional MNU treatment but no inhibitory effects of IM were noted. A low frequency of p53 mutations was detected without relation to the extent of tumor invasion. Thus, only two mutations were found, one in a Ta and the other in a T1 carcinoma. The present study thus demonstrated that p53 mutations are not involved in MNU-induced progression in rat urinary bladder cancers, suggesting that they are not critical for malignancy.

Animals↗

Promotion of NCI-Black-Reiter male rat bladder carcinogenesis by dimethylarsinic acid an organic arsenic compound.

Dimethylarsinic acid (DMAA) is a major metabolite of inorganic arsenicals in mammals. In the present study, we investigated its promoting effects on urinary bladder carcinogenesis in NCI-Black-Reiter (NBR) rats, which lack alpha2u-globulin synthesizing ability. Male 9-14-week-old NBR rats were treated sequentially with 0.05% N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) for 4 weeks and then given 100 ppm DMAA in their drinking water (group 1) for 32 weeks. Induction of preneoplastic lesions (papillary or nodular hyperplasia) in this DMAA-treated group was significantly increased as compared to the carcinogen alone control group (P < 0.01). The development of carcinomas was also enhanced and a significant increase in the 5-bromo-2'-deoxyuridine (BrdU) labeling index of the urinary bladder epithelial cells was observed for the DMAA treatment group. These results indicate that DMAA has promoting effects on urinary bladder carcinogenesis even in NBR rats, so its effects are not dependent on the presence of alpha2u-globulin.

Alpha-Globulins↗

Enhancement of urinary bladder carcinogenesis in nullizygous p53-deficient mice by N-butyl-N-(4-hydroxybutyl)nitrosamine.

We recently reported p53 mutations to be frequent in mouse invasive urinary bladder carcinomas, with and without metastasis. However, the role of p53 dysfunctions during carcinogenesis remains unclear. In the present study, heterozygous and nullizygous p53-deficient mice and their littermates were treated with the urinary bladder carcinogen, N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN), at a concentration of 0.01% in the drinking water throughout the experiment. This markedly accelerated urinary bladder carcinogenesis but not development of other tumors in the nullizygous p53-deficient mice. Thus the appearance of neoplastic urothelial lesions in nullizygotes (at day 60 of the experiment) was earlier than in wild-type mice and heterozygotes (at day 125). Moreover, malignant vascular tumors (hemangiosarcomas (HS)) were found in all four nullizygotes killed later than day 108. Mutational inactivation of the wild-type allele was not apparent in either the single transitional cell carcinoma observed in a wild-type mouse and a hemangiosarcoma in a heterozygote. Overall, it can be concluded that the number of normal p53 alleles is a significant determining factor in the susceptibility of urothelial cells to carcinogens. The role of the p53 defect in mouse urinary bladder carcinogenesis may thus be to diminish the threshold for occurrence of additional genetic alterations.

Animals↗

Promoting effects of intravesical instillation of saline on bladder lesion development in rats pretreated with N-butyl-N-(4-hydroxybutyl) nitrosamine are inhibited by bacillus Calmette-Guerin.

The promoting effects of intravesical instillation of saline and the efficacy of bacillus Calmette-Guerin (BCG) for prophylaxis of bladder carcinogenesis were assessed. Rats were given 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) for 10 weeks; they were then given 6 weekly intravesical instillations of BCG, saline or distilled water starting 1 week or 15 weeks after the BBN treatment. At 32 weeks, both the incidences and numbers of bladder cancers were elevated in animals receiving the saline. An exception was the early phase BCG group. Significant increases in tumor size were also noted for the saline, but not the distilled water group. The results indicate that intravesical instillation of saline promotes urinary bladder carcinogenesis. However, the inhibitory influence of BCG was suggested if administered at the early, but not the late phase, of carcinogenesis.

Animals↗

Concentration dependent promoting effects of sodium L-ascorbate with the same total dose in a rat two-stage urinary bladder carcinogenesis.

Sodium L-ascorbate (Na-AsA) has been demonstrated to be a strong promoter of rat urinary bladder tumor development initiated by N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN). In the present study, we investigated variation in its promoting activity when the same total dose was given with different concentrations and exposure times. After 4 weeks administration of 0.05% BBN, group 1 served as a control without any post-initiation treatment. The rats in groups 2-4 received 1.25% Na-AsA diet for 36 weeks, 2.5% Na-AsA for 18 weeks and 5% Na-AsA for 8 weeks, respectively. Tumor number (papillomas and carcinomas) was greatest in group 3, and area in group 4 (P < 0.05). However, no enhancement was noted in group 2, although preneoplastic lesions were significantly increased. These results suggest that with the same total administration dose, high concentration of Na-AsA has the strongest promoting effects on tumor development in urinary bladder carcinogenesis.

Animals↗

Post-initiation effects of a super critical extract of propolis in a rat two-stage carcinogenesis model in female F344 rats.

Post-initiation modifying effects of dietary administration of a super critical extract of propolis on major organs were examined using a two-stage carcinogenesis model. Groups of 21 or 22 F344 female rats were treated sequentially with 2,2'-dihydroxy-di-n-propylnitrosamine (DHPN, i.g.), 7,12-dimethylbenz[a]anthracene (DMBA, i.g.), 1,2-dimethylhydrazine (DMH, s.c.) and N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN, in drinking water) during the first 3 weeks for initiation, and then administered diet containing 0.1 or 0.01% propolis for 33 weeks. Further groups were treated with the carcinogens alone, 0.1% propolis alone or basal diet alone. All surviving animals were killed at week 36, and major organs were examined histopathologically for development of preneoplastic and neoplastic lesions. The incidence and multiplicity of mammary carcinomas were significantly decreased by the 0.1 and 0.01% propolis treatments. In the urinary bladder, the incidence of PN hyperplasia but not tumors was, in contrast, significantly increased by 0.1% propolis. Similarly, the number and area of glutathione S-transferase placental form (GST-P)-positive liver foci were significantly elevated with this high dose. The results indicate that a low dose of a super critical extract of propolis may find application as a potent chemopreventor of mammary carcinogenesis.

1,2-Dimethylhydrazine↗

Inhibitory effect of peptide vilon on the development of induced rat urinary bladder tumors in rats.

The effect of peptide vilon (Lys-Glu) on urinary bladder carcinogenesis in rats was studied. Urinary bladder tumors were induced with a selective carcinogen N-butyl-N-(4-hydroxybutyl)nitrosamine. The tumors developed in 56% vilon-treated animals and in 75.5% controls. Vilon 2-fold decreased the incidence of preneoplastic and early neoplastic changes in urinary bladder mucosa and significantly inhibited carcinogenesis.

Adjuvants, Immunologic↗