Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029463 (osteosarcoma)
 16,637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have recently identified a locus exhibiting a high frequency of allelic imbalance (AI) in both spontaneous human (HSA 6q14.1-15) and radiogenic murine (MMU9, 42 cM) osteosarcoma. Here we describe the fine mapping of the locus in osteosarcoma arising in (BALB/cxCBA) F(1) hybrid mice. These studies have allowed us to identify Tbx18, a member of the T-box transcriptional regulator gene family, as a candidate gene. Three intragenic Tbx18 polymorphisms were used to map the region of maximum AI to within the gene itself; 16 of 17 tumours exhibited imbalances of at least one of these markers. The highest frequency was found in exon 1, where 14 of 17 tumours were affected at a single nucleotide polymorphism at 541 nt. Two polymorphic CA repeat markers in intron 2 and intron 5 demonstrated overlapping regions of imbalance in several tumours. Both markers flanking the Tbx18 gene (D9Osm48 and D9Mit269) revealed significantly lower frequencies of imbalance and confirmed the limitation of the common interval to Tbx18. Examination of both the mouse and human annotated genomic sequences indicated Tbx18 to be the only gene within the interval. Sequence analysis of the Tbx18 coding region did not reveal any evidence of mutation. Given the haploinsufficiency phenotypes reported for other T-box genes, we speculate that AI may influence the function of Tbx18 during osteosarcomagenesis.
Carcinogenesis 2003 Mar
PMID:Allelic imbalance at intragenic markers of Tbx18 is a hallmark of murine osteosarcoma. 1266 94

N,N-Dimethylaniline is used as a chemical intermediate in the synthesis of dyestuffs. Toxicology and carcinogenesis studies were conducted by administering N,N-dimethylaniline (greater than 98% pure) in corn oil by gavage to groups of F344/N rats and B6C3F1 mice of each sex for 2 weeks, 13 weeks, or 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, mouse lymphoma cells, and Chinese hamster ovary (CHO) cells. Two-Week and Thirteen-Week Studies: In the 2-week studies, doses were 94-1,500 mg/kg; deaths of rats and mice were observed in groups given doses of 750 or 1,500 mg/kg. The final mean body weights of male rats that received 375 or 750 mg/kg were 15% or 47% lower than that of vehicle controls; final mean body weights of other groups of rats and mice were similar to those of vehicle controls. Compound-related clinical signs observed included cyanosis in rats and lethargy and tremors in rats and mice. Splenomegaly occurred in nearly all dosed groups of rats and mice, and the incidences were dose related. In the 13-week studies, doses were 32-500 mg/kg; no compound-related deaths occurred. The final mean body weights of male rats that received 250 or 500 mg/kg were 15% or 27% lower than that of vehicle controls. The final mean body weights of all groups of dosed female rats and male and female mice were within 12% of those of vehicle controls. Compound-related clinical signs included lethargy in rats and mice and cyanosis in rats. Splenomegaly was observed in all dosed groups of rats and mice; the severity was dose related. Compound-related extramedullary hematopoiesis and hemosiderosis occurred in the kidney or testis of dosed rats and liver and spleen of dosed rats and mice. Two-year studies were conducted by administering 0, 3, or 30 mg/kg N,N-dimethylaniline in corn oil by gavage, 5 days per week for 103 weeks, to groups of 50 rats of each sex. The lower dose was selected to be one-tenth the higher dose to increase the likelihood that one dose would cause only a minimal nonneoplastic response. Groups of 50 mice of each sex were administered 0, 15, or 30 mg/kg on the same schedule. Body Weight and Survival in the Two-Year Studies: Mean body weights of vehicle control and dosed rats and mice were similar throughout the studies. Survival rates of all respective groups were similar after 2 years, except for the lowered survival of vehicle control female rats (vehicle control, 21/50; low dose 32/50; high dose, 36/50). This may reflect the large number (24/50) of vehicle control female rats killed when observed to be in a moribund state. Final survival for other groups was as follows: male rats--29/50; 32/50; 28/50; male mice-- 34/50; 30/50; 34/50; female mice--35/50; 39/50; 33/50. Nonneoplastic and Neoplastic Effects in the Two-Year Studies: In these 2-year studies, the spleen was the expected site of chemical-related effects. Fatty metamorphosis and fibrosis in the spleen of high dose male rats were increased (fatty metamorphosis: vehicle control, 0/49; low dose, 1/49; high dose, 10/50; fibrosis: 5/49; 2/49; 22/50). Splenic hemosiderosis and hematopoiesis were present at an incidence greater than 85% in all groups of rats; however, the severity of the lesions was greater in dosed groups than in vehicle controls. Sarcomas of the spleen were seen in 3/50 high dose male rats, and an osteosarcoma was seen in another high dose male rat. One additional high dose male rat had a sarcoma of the thymus. Splenic sarcomas are uncommon in corn oil vehicle control male F344/N rats (NTP historical incidence 3/2,081, 0.1%), and thus, these neoplasms in high dose male rats (4/50, 8%) were considered to be chemically related. Lower incidences of mononuclear cell leukemia (which apparently originates in the spleen) were seen in dosed male and female rats than in vehicle controls (male: 13/50; 4/50; 3/50; female: 11/50; 7/50; 0/50). The incidence of squamous cell papillomas of the forestomach in high dose female mice was marginally greater than that in vehicle controls (2/50; 2/50; 8/50). No malignant forestomacin vehicle controls (2/50; 2/50; 8/50). No malignant forestomach neoplasms were observed. Genetic Toxicology: N,N-Dimethylaniline was not mutagenic in S. typhimurium strains TA98, TA100, TA1535, or TA1537 in the presence or absence of exogenous metabolic activation. In the mouse lymphoma assay, N,N-dimethylaniline produced a positive response with and without metabolic activation. In CHO cells, N,N-dimethylaniline induced both sister chromatid exchanges (SCEs) and chromosomal aberrations in the presence of exogenous metabolic activation. Without activation, an increase in chromosomal aberrations was observed, but no increase in SCEs occurred. Conclusions: Under the conditions of these 2-year gavage studies, there was some evidence of carcinogenic activity of N,N-dimethylaniline for male F344/N rats, as indicated by the increased incidences of sarcomas or osteosarcomas(combined) of the spleen. There was no evidence of carcinogenic activity of N,N-dimethylaniline for female F344/N rats given 3 or 30 mg/kg body weight by gavage for 2 years. There was no evidence of carcinogenic activity of N,N-dimethylaniline for male B6C3F1 mice given 15 or 30 mg/kg body weight by gavage for 2 years. There was equivocal evidence of carcinogenic activity of N,N-dimethylaniline for female B6C3F1 mice, as indicated by an increased incidence of squamous cell papillomas of the forestomach. Both rats and mice could have tolerated doses higher than those used in these studies. There were decreased incidences of mononuclear cell leukemia in dosed male and high dose female rats. Compound-related splenic fibrosis, hemosiderosis, and fatty metamorphosis were increased in male rats. Synonyms: dimethylaminobenzene; N,N-dimethylbenzeneamine; dimethylaniline; dimethylphenylamine; N,N-dimethylphenylamine
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PMID:Toxicology and Carcinogenesis Studies of N,N-Dimethylaniline (CAS No. 121-69-7) in F344/N Rats and B6C3F1 Mice (Gavage Studies). 1269 81

p-Chloroaniline has a large production volume and is used as a dye intermediate. Toxicology and carcinogenesis studies of p-chloroaniline (greater than 99% pure) were conducted by administering p-chloroaniline hydrochloride in water by gavage to groups of F344/N rats and B6C3F1 mice of each sex for 16 days, 13 weeks, or 2 years. Vehicle controls were given deionized water by gavage. All doses were calculated as p-chloroaniline; the chemical was administered as the hydrochloride after dissolution in water containing molar equivalents of hydrochloric acid. Genetic toxicology studies were conducted in Salmonella typhimurium, mouse L5178Y lymphoma cells, and Chinese hamster ovary (CHO) cells. Hematologic parameters were measured at the end of the 13-week studies and at 6, 12, 18, and 24 months in the 2-year studies. Supplemental studies of the distribution and disposition of p-chloroaniline were conducted in male F344 rats. Sixteen-Day and Thirteen-Week Studies: In the 16-day studies, male and female rats and mice received 25, 50, 100, or 400 mg/kg of body weight. The vehicle controls received deionized water. All rats and mice that received 200 or 400 mg/kg died during the first 6 days of the studies. Some deaths occurred in each of the lower dose groups of mice. Splenic enlargement was observed at necropsy in rats administered 25, 50, or 100 mg/kg. Congestion of the spleen and hemosiderin deposition in the renal cortical tubular epithelial cells were observed at 100 mg/kg in male and female rats. Compound-related lesions in mice included hemosiderosis of the liver Kupffer cells and congestion of the spleen. In the 13-week studies, 10 rats of each sex were administered doses of 0, 5, 10, 20, 40, or 80 mg/kg. All male rats lived to the end of the 13-week studies. One of 10 female rats that received 80 mg/kg died from unknown causes. The final mean body weights of rats that received 80 mg/kg were 16% lower than that of vehicle controls for males and 4% lower for females. In the 13-week studies in mice, 10 animals of each sex were administered doses of 0, 7.5, 15, 30, 60, or 120 mg/kg. Deaths in mice were not related to p-chloroaniline hydrochloride administration. The final mean body weights of dosed and vehicle control mice were similar. In both rats and mice, no chemically related effects on organ weights were observed at necropsy, except for the spleen, which was enlarged as a function of increasing dose. Methemoglobin was increased in dosed groups and resulted in a secondary anemia, the severity of which was dose related. Compound-related lesions observed histologically, including pigmentation (hemosiderin) in the kidney, spleen, and liver and hematopoiesis in the liver and spleen, reflected the response to the hemolytic anemia and methemoglobinemia induced by p-chloroaniline hydrochloride. Based on these results, groups of 50 rats of each sex were administered 2, 6, or 18 mg/kg p-chloroaniline hydrochloride in water by gavage, 5 days per week for 103 weeks. Groups of 50 mice of each sex were administered 3, 10, or 30 mg/kg on the same schedule. Metabolism and Disposition Studies in Rats: The metabolism and disposition studies in F344/N rats showed that metabolic and excretory pathways were not saturated by p-chloroaniline administered orally at doses ranging from 0.3 to 30 mg/kg. p-Chloroaniline was rapidly metabolized and excreted primarily in urine with a half-life of approximately 2 hours. Body Weight and Survival in the Two-Year Studies: Mean body weights of dosed rats were generally within 5% of those of vehicle controls throughout the studies. The survival of the low and mid dose groups of male rats and of the low and high dose groups of female rats was significantly greater than that of the vehicle controls (male: vehicle control, 18/49; low dose, 32/50; mid dose, 32/50; high dose, 21/50; female: 27/50; 39/50; 36/50; 37/50). The increased survival was attributed to the decreased incidences of mononuclear cell leukemia. Mean body weights of high dose male and female mice were generally within 5% of those of vehiclwithin 5% of those of vehicle controls throughout the studies. The survival of the mid dose group of male mice was lower than that of the vehicle controls after week 99 (male: 43/50; 36/50; 29/50; 35/50; female: 39/50; 42/50; 44/50; 41/50). Nonneoplastic and Neoplastic Effects in the Two-Year Studies: Fibrosis of the spleen was increased in dosed male and high dose female rats (male: vehicle control, 3/49; low dose, 11/50; mid dose, 12/50; high dose, 41/50; female: 1/50; 2/50; 3/50; 42/50). Cellular infiltration of lipocytes (fatty metaplasia) was observed in the spleen at increased incidences in high dose rats (male: 0/49; 0/50; 0/50; 24/50; female: 0/50; 0/50; 0/50; 11/50). The incidence of uncommon sarcomas of the spleen in high dose male rats was significantly greater than that in the vehicle controls (fibrosarcomas, osteosarcomas, or hemangiosarcomas, combined: 0/49; 1/50; 3/50; 38/50). Many of these tumors metastasized to one or more sites. In female rats, one fibrosarcoma of the spleen was found in a mid dose animal, and one osteosarcoma of the spleen was found in a high dose animal. The historical incidence of splenic connective tissue sarcomas (all types) in water gavage vehicle controls is 1/298 (0.3%) for male rats and 0/297 for female rats. The historical incidence of hemangiosarcomas in water gavage controls is 0/300 for male rats and 1/297 (0.3%) for female rats. Adrenal medullary hyperplasia was observed at an increased incidence in high dose female rats (4/50; 4/50; 7/50; 24/50). Marginally increased incidences of pheochromocytomas were seen in high dose male (13/49; 14/48; 15/48; 26/49) and female (2/50; 3/50; 1/50; 6/50) rats. The historical incidence of pheochromocytomas in water gavage vehicle control male F344/N rats is 121/299 (40% ± 16%); the historical incidence in water gavage vehicle control female F344/N rats is 20/295 (7% ± 2%). The incidences of mononuclear cell leukemia in dosed male and female rats were lower than those in vehicle controls (male: 21/49; 3/50; 2/50; 3/50; female: 10/50; 2/50; 1/50; 1/50). The incidences of malignant lymphomas in dosed male and female mice were lower than those in vehicle controls (male: 10/50; 3/49; 9/50; 3/50; female: 19/50; 12/50; 5/50; 10/50). Hematologic and methemoglobin measurements were made on blood samples collected from 15 randomly selected male and female rats per dose group at 6, 12, 18, and 24 months. In general, the high dose group at various intervals showed mild hemolytic anemia and dose-related increases in methemoglobin. In rats, compound-related nonneoplastic lesions were seen histopathologically in the bone marrow, spleen, and liver. These lesions included bone marrow hyperplasia, hepatic hemosiderosis, and splenic fibrosis and suggest compound-related effects on the hematopoietic system in general, the erythropoietic system specifically, and mesenchymal cells in the spleen. In male mice, the incidence of hemangiosarcomas of the liver or spleen in high dose male mice was greater than that in the vehicle controls (4/50; 4/49; 1/50; 10/50). The historical incidence of hemangiomas or hemangiosarcomas at all sites (combined) in water gavage vehicle control male B6C3F1 mice is 11/350 (3% ± 3%). The incidences of hepatocellular adenomas or carcinomas (combined) were increased in dosed male mice (11/50; 21/49; 20/50; 21/50), primarily due to increased incidences of hepatocellular carcinomas (3/50; 7/49; 11/50; 17/50). Hepatocellular carcinomas metastasized to the lung in 1/50 vehicle control, 1/49 low dose, 2/50 mid dose, and 9/50 high dose male mice. The historical incidence ofhepatocellular neoplasms in water gavage vehicle controls is 106/347 (31 ± 6%). Genetic Toxicology: p-Chloroaniline was mutagenic in S. typhimurium strains TA98 and TA100 in the presence of exogenous metabolic activation; no increase in revertant colonies was observed in strains TA97, TA1535, or TA1537. p-Chloroaniline induced trifluorothymidine (Tft) resistance in mouse L5178Y lymphoma cells with and without metabolic activation. In cultured CHO cells, treatment with p-chloroaniline produced significant increases in sister chromatid exchanges (SCEs) both with and without metabolic activation (S9); chromosomal aberrations were significantly increased only in the presence of S9. Audit: The data, documents, and pathology materials from the 2-year studies of p-chloroaniline have been audited. The audit findings show that the conduct of the studies is documented adequately and support the data and results given in this Technical Report. Conclusions: Under the conditions of these 2-year water gavage studies, there was clear evidence of carcinogenic activity of p-chloroaniline hydrochloride for male F344/N rats, as indicated by increased incidences of uncommon sarcomas of the spleen. Pheochromocytomas of the adrenal gland may also have been associated with chemical administration. There was equivocal evidence of carcinogenic activity of p-chloroaniline hydrochloride for female F344/N rats, as indicated by the presence of uncommon sarcomas of the spleen in one mid and one high dose animal and the increased incidence of pheochromocytomas of the adrenal gland. There was some evidence of carcinogenic activity of p-chloroaniline hydrochloride for male B6C3F1 mice, as indicated by increased incidences of hepatocellular neoplasms and of hemangiosarcomas of the liver or spleen. There was no evidence of carcinogenic activity of p-chloroaniline hydrochloride for female B6C3F1 mice administered 3, 10, or 30 mg/kg by gavage for 2 years. The incidences of mononuclear cell leukemia in male and female rats and of malignant lymphomas in male and female mice were decreased by administration of p-chloroaniline hydrochloride. Compound-related splenic fibrosis was present in male and female rats. Synonyms: 1-amino-4-chlorobenzene hydrochloride; 4-chlorophenylamine hydrochloride; 4-chlorobenzeneamine hydrochloride
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PMID:NTP Toxicology and Carcinogenesis Studies of para-Chloroaniline Hydrochloride (CAS No. 20265-96-7) in F344/N Rats and B6C3F1 Mice (Gavage Studies). 1270 33

Nitrofurantoin was studied and evaluated because of its widespread use as a drug for treating urinary tract infections in humans, its structural relationship to known carcinogenic 5-nitrofuran compounds, and the lack of adequate studies to assess its carcinogenicity. Toxicology and carcinogenesis studies of nitrofurantoin were conducted by administering nitrofurantoin (greater than 99% pure) in feed to groups of F344/N rats and B6C3F1 mice of each sex for 14 days, 13 weeks, or 2 years. Fourteen-Day and Thirteen-Week Studies: None of the rats (at dietary concentrations up to 20,000 ppm) died before the end of the 14-day studies. Rats that received 5,000, 10,000, or 20,000 ppm lost weight. Four of five male and 4/5 female mice that received 10,000 ppm and 1/5 females that received 5,000 ppm nitrofurantoin died before the end of the studies. Mice that received 5,000 ppm and male mice that received 10,000 ppm lost weight. In the 13-week studies, final mean body weights of rats that received 2,500, 5,000, or 10,000 ppm were 10%, 34%, or 47% lower than that of the controls for males and 15%, 31%, or 41% lower for females. Feed consumption by dosed and control rats was generally similar. Degeneration of the germinal epithelium of the seminiferous tubules of the testis was observed in male rats that received 2,500 to 10,000 ppm nitrofurantoin. Necrosis of the ovarian follicles was observed in 8/10 female rats that received 10,000 ppm, in 3/10 females that received 5,000 ppm, and in 1/10 that received 2,500 ppm. For mice, final mean body weights of the 5,000-ppm groups were 13% lower than that of the controls for males and 15% lower for females. Two of 10 male mice that received 5,000 ppm and 1/10 males that received 300 ppm died before the end of the 13-week studies. Estimated feed consumption was similar for dosed and control groups. Degeneration of the germinal epithelium of the testis was observed in males that received 1,300 to 5,000 ppm; necrosis of the ovarian follicles was observed in females that received 5,000 ppm but not in the lower dose groups. Necrosis of the renal tubular epithelium was observed in 2/9 males that received 5,000 ppm. Based on these results, 2-year studies of nitrofurantoin were conducted by feeding diets containing 0, 1,300, or 2,500 ppm nitrofurantoin to groups of 50 male F344/N rats and to groups of 50 male and female B6C3F1 mice for 103 weeks. Groups of 50 female F344/N rats were fed diets containing 0, 600, or 1,300 ppm nitrofurantoin on the same schedule. Body Weight and Survival in the Two-Year Studies: Mean body weight and average daily feed consumption of dosed male and female rats were similar to those of the controls throughout the studies. The average amount of nitrofurantoin consumed per day was estimated to be 60 and 110 mg/kg for low and high dose male rats and 30 and 60 mg/kg for low and high dose female rats. No significant differences in the number of rats surviving to the end of the studies were observed between any groups of rats of either sex (male: control, 24/50; low dose, 27/50; high dose, 26/50; female: 25/50; 26/50; 31/50). Mean body weights of high dose male and female mice were up to 12% lower than those of the controls throughout most of the studies. The average daily feed consumption by dosed mice ranged from 93% to 100% that by controls. The average amount of nitrofurantoin consumed per day was estimated to be 280-300 mg/kg and 570-580 mg/kg for low and high dose mice. The survival of the control group of female mice was lower than that of the dosed groups (control, 19/50; low dose, 37/50; high dose, 37/50). The decrease in survival was most likely related to the increase in microbial infection in the reproductive tract observed in the controls. Groups of male mice had similar survival (28/50; 29/50; 34/50). Nonneoplastic and Neoplastic Effects in the Two-Year Studies: Organs showing toxicity from nitrofurantoin exposure identified in the short-term studies were the testis in male rats and mice, the ovary in female rats and mice, and the kidney in male mice. Lesions oband mice, the ovary in female rats and mice, and the kidney in male mice. Lesions observed in the 2-year studies were in the testis in male rats and mice, ovary in female mice, and kidney in male rats. Chronic nephropathy was observed in nearly all rats, but the severity of the lesions was judged to be greater in dosed male rats. Hyperplasia of the transitional cell epithelium (control, 0/50; low dose, 5/50; high dose, 2/50) and hydronephrosis of the renal pelvis (0/50; 5/50; 2/50) were also observed in dosed male rats. In the standard single sections of the left and right kidney from each rat, tubular cell adenomas were observed in one low dose and two high dose males; a tubular cell carcinoma was observed in another high dose male. Because the number of renal tubular cell neoplasms identified by standard procedures in the dosed male rats was low, additional step-sections of the kidney were evaluated. The incidences of tubular cell adenomas derived from the step-sections and original sections (combined) were significantly increased in dosed male rats (adenomas: 3/50; 11/50; 19/50); tubular cell carcinomas occurred in two high dose males only. Lesions considered to be associated with the nephropathy and nitrofurantoin exposure were observed in male rats and included hyperplasia of the parathyroid glands (3/49; 18/47; 23/49), fibrous osteodystrophy of the bone (0/50; 5/50; 5/50), and mineralization of the glandular stomach (1/49; 8/50; 14/50). Atypical cells of the epididymis (0/50; 0/50; 12/50) and degeneration of the testis (0/50; 0/50; 36/50) were observed in high dose male rats. Fibrinoid necrosis of arterioles (1/50; 8/50; 15/50) and perivascular infiltration of mononuclear cells (3/50; 9/50; 19/50) were also observed in the testis of male rats. Interstitial cell adenomas of the testis occurred with a negative trend (47/50; 45/50; 21/50), and no adenomas or carcinomas of the preputial gland were seen in high dose male rats (12/48; 11/50; 0/47). The incidence of clitoral gland neoplasms was increased in low dose female rats (5/44; 10/38; 4/42). Osteosarcomas were observed in the bone of one low dose and two high dose male rats. The historical incidence of osteosarcomas in untreated male F344/N rats is 8/1,937 (0.4%). The incidences of subcutaneous tissue neoplasms in dosed male rats were greater than that in the controls (1/50; 7/50; 5/50). No neoplastic lesions in dosed female rats or male mice were considered to be compound related at the doses of nitrofurantoin administered. For female mice, ovarian atrophy was observed in 48/50 low dose and 49/50 high dose mice but not in controls. Tubular cell adenomas of the ovary (0/50; 0/50; 5/50), benign mixed tumors (tubular and stromal) (0/50; 0/50; 4/50), and granulosa cell tumors (0/50; 3/50; 2/50)) were observed in dosed female mice. One granulosa cell tumor in the high dose group was malignant. Ovarian abscesses (18/50) and suppurative inflammation of the uterus (11/50) were observed in control female mice but not in dosed female mice and are believed to be related to indigenous microbial infections and most likely were the cause of early deaths in this group. Adenocarcinomas of the uterus were seen in one low dose and in one high dose mouse. Testicular aspermatogenesis (1/49; 1/49; 16/50), degeneration of the germinal epithelium (0/49; 3/49; 23/50), and atypical cells (0/50; 0/49; 26/50) and depletion (1/50; 1/49; 15/50) of the epididymis were observed at increased incidences in high dose male mice. Spindle cell hyperplasia of the adrenal cortex was observed in dosed female mice (3/50; 41/50; 45/50). A spindle cell adenoma (adrenal capsule adenoma) was seen in one low dose female mouse, and a spindle cell carcinoma (adrenal capsule carcinoma) was seen in one low dose male mouse. Mineralization of the renal medulla (male: 0/50; 0/50; 17/50; female: 0/50; 0/50; 7/50) and dilatation of the renal tubules (male: 0/50; 0/50; 14/50) were observed in high dose mice. Hepatocellular neoplasms (adenomas or carcinomas, combined) were observed at an increased incidence in high dose female mice (2/50; 2/50; 8/50). An Ito cell tumor of the liver was observed in one low dose and one high dose female mouse. Malignant lymphomas occurred in female mice (12/50; 19/50; 24/50). Genetic Toxicology: Nitrofurantoin was mutagenic in Salmonella typhimurium strains TA98 and TA100, with and without metabolic activation, but was not mutagenic for strains TA1535 or TA1537. Nitrofurantoin induced forward mutations at the TK+/- locus of L5178Y mouse lymphoma cells in the absence of metabolic activation (it was not tested with activation). Nitrofurantoin induced increased numbers of sister chromatid exchanges and chromosomal aberrations in cultured Chinese hamster ovary cells with and without metabolic activation. Results of the sex-linked recessive lethal assay in Drosophila were negative after administration of nitrofurantoin by feeding or by injection. Conclusions: Under the conditions of these 2-year feed studies, there was some evidence of carcinogenic activity of nitrofurantoin for male F344/N rats as shown by increased incidences of uncommon kidney tubular cell neoplasms. Uncommon osteosarcomas of the bone and neoplasms of the subcutaneous tissue were observed in dosed male rats. Incidences of interstitial cell adenomas of the testis and neoplasms of the preputial gland were decreased in the 2,500-ppm group of male rats. There was no evidence of carcinogenic activity of nitrofurantoin for female F344/N rats fed diets containing 600 ppm or 1,300 ppm for 2 years. Female rats may have been able to tolerate higher doses. There was no evidence of carcinogenic activity of nitrofurantoin for male B6C3F1 mice fed diets containing 1,300 ppm or 2,500 ppm for 2 years. There was clear evidence of carcinogenic activity of nitrofurantoin for female B6C3F1 mice as shown by increased incidences of tubular adenomas, benign mixed tumors, and granulosa cell tumors of the ovary. Nonneoplastic lesions considered related to nitrofurantoin exposure were chronic nephropathy and associated lesions (hyperplasia of the parathyroid gland, fibrous osteodystrophy of the bone, and mineralization of the glandular stomach) in male rats and testicular degeneration in male rats and mice. Ovarian atrophy and hyperplasia of the adrenal cortex spindle cells were observed in dosed female mice. Synonyms: 1-(((5-nitro-2-furanyl)methylene)amino-2,4-imidazolidinedione); 1-(5-nitro-2-furfurylideneamino)-hydantoin; N-(5-nitro-2-furfurlidene)-1-aminohydantoin; 1-((5-nitrofurfurylidene)amino)hydantoin Trade Names: Benkfuran; Benkfurin; Chemiofuran; Cyantin; Dantafur; Furadantin; Furadantine; Furadantoin; Furadonin; Furadonine; Furantoin; Furatoin; Furobactina; Ituran; Macrodantin; Nifurantin; NSC 2107; N-Toin; Orafuran; Parafuran; Urizept; USAF EA-2; Welfurin; Zoofurin
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PMID:NTP Toxicology and Carcinogenesis Studies of Nitrofurantoin (CAS No. 67-20-9) in F344/N Rats and B6C3F1 Mice (Feed Studies). 1272 84

2-Amino-5-nitrophenol is used as a colorant in semipermanent hair dyes and in the manufacture of C.I. Solvent Red 8, an azo dye for synthetic resins, lacquers, and wood stains. 2-Amino-5-nitrophenol was nominated for toxicology and carcinogenesis studies by the National Cancer Institute because of widespread human exposure associated with its use in hair dyes. Toxicology and carcinogenesis studies were conducted by administering 2-amino-5-nitrophenol (98% pure) by gavage in corn oil 5 days per week to groups of F344/N rats and B6C3F1 mice of each sex in 16-day, 13-week, and 2-year studies. In the 2-year studies, male and female rats were given doses of 0, 100, or 200 mg/kg and male and female mice were given doses of 0, 400, or 800 mg/kg. Sixteen-Day and Thirteen-Week Studies: During the 16-day studies, F344/N rats of each sex received 0, 156, 313, 625, 1,250, or 2,500 mg/kg 2-amino-5-nitrophenol by gavage in corn oil vehicle. One of the five males that received 2,500 mg/kg, 1/5 females that received 1,250 mg/kg, and 2/5 females that received 313 mg/kg died before the end of the studies. Final mean body weights of rats that received 1,250 or 2,500 mg/kg were 11% and 30% lower than that of vehicle controls for males and 9% and 13% lower for females. B6C3F1 mice of each sex received doses of 0, 313, 625, 1,250, 2,500, or 5,000 mg/kg 2-amino-5-nitrophenol. Two of five males and 5/5 females that received 5,000 mg/kg, 3/5 males and 3/5 females that received 2,500 mg/kg, 3/5 females that received 1,250 mg/kg, 1/5 females that received 625 mg/kg, and 2/5 male vehicle controls died before the end of the studies. Final mean body weights of chemically exposed mice were not different from those of the vehicle controls. Rats that received 625, 1,250, or 2,500 mg/kg and male mice that received 5,000 mg/kg had loose stools. In 13-week studies, F344/N rats and B6C3F1 mice of both sexes received 0, 100, 200, 400, 800, or 1,600 mg/kg 2-amino-5-nitrophenol by gavage in corn oil. Five of 10 male and 2/10 female rats that received 1,600 mg/kg, 1/10 male and 3/10 female rats that received 800 mg/kg, and 1/10 male rats that received 400 mg/kg died before the end of the studies. Final mean body weights of males that received 400, 800, or 1,600 mg/kg were 10%, 25%, and 43% lower than that of vehicle controls. The final mean body weight of females that received 1,600 mg/kg was 16% lower that of vehicle controls. Four of 10 male and 3/10 female mice that received 1,600 mg/kg died before the end of the 13-week studies. The final mean body weight of male mice that received 1,600 mg/kg was 11% lower than that of vehicle controls; male and female mice that received 1,600 mg/kg appeared lethargic. During the 13-week studies, acute/chronic perivasculitis of vessels of the cecum and colon was observed in rats that received 400, 800, or 1,600 mg/kg and in mice that received 1,600 mg/kg. Body Weight and Survival in the Two-Year Studies: Mean body weights of rats receiving 200 mg/kg were 5%-10% lower than those of vehicle controls after week 33 for males and 4%-5% lower than those of vehicle controls after week 93 for females. Survival of male rats was significantly lower than that of vehicle controls after week 99 for the 100 mg/kg dose group and after week 75 for the 200 mg/kg dose group (final survival: vehicle control, 33/50; 100 mg/kg group, 16/50; 200 mg/kg group, 4/50). Survival of female rats was comparable to that of vehicle controls (30/50; 32/50; 29/50). Loose or poorly formed stools were observed for male rats and occasionally for females that received 200 mg/kg. Mean body weights of mice that received 800 mg/kg were 8%-11% lower than those of vehicle controls between weeks 29 and 74 for males and 8%-13% lower than those of vehicle controls after week 69 for females; mean body weights of mice that received 400 mg/kg were greater than those of vehicle controls after week 69 for males and 5%-9% lower than those of vehicle controls after week 69 for females. Survival of mice that received 800 mg/kg was significantly reduced compared with that of ose of vehicle controls after week 69 for females. Survival of mice that received 800 mg/kg was significantly reduced compared with that of vehicle controls after week 20 for males and week 22 for females and was not considered adequate to evaluate a carcinogenic response (final survival--male: vehicle control, 31/50; 400 mg/kg group, 36/50; 800 mg/kg group, 12/50; female: 37/50; 36/50; 10/50). Nonneoplastic and Neoplastic Effects in the Two-Year Studies: Pigmentation was present at increased incidences in all groups of chemically exposed animals and was characterized by varying amounts of an orange, granular pigment present in the fibrous connective tissue of the lamina propria, in the submucosa, and around vessels in the submucosa of the cecum and colon. Pigmentation of the rectum was observed at increased incidences in male rats that received 100 mg/kg, male and female rats that received 200 mg/kg, and both groups of chemically exposed mice. No pigmentation was found in the intestines of vehicle control rats or mice. Associated with pigmentation was an increased incidence of acute/chronic inflammation in the cecum and colon of all groups chemically exposed rats and mice; this inflammation was similar to that observed in the 13-week studies but was of greater severity. Acute/chronic inflammation was also present in the rectum of male rats that received 100 mg/kg, male and female rats that received 200 mg/kg, and male mice that received 800 mg/kg. The incidence of pancreatic acinar cell adenomas was significantly increased (P≤0.002) in male rats that received 100 mg/kg 2-amino-5-nitrophenol (vehicle control, 1/50; 100 mg/kg, 10/50; 200 mg/kg, 3/49); the increase was considered to be associated with chemical exposure. The reduced survival of male rats that received 200 mg/kg markedly reduced the sensitivity of this group for detecting the presence of neoplasms. The incidences of adenomas or carcinomas (combined) of the preputial or clitoral glands were marginally increased in male or female rats that received 200 mg/kg 2-amino-5-nitrophenol (preputial gland: 3/50; 2/50; 5/50; clitoral gland: 3/50; 3/50; 7/50). Neoplasms found in the intestinal tract of 3/50 male rats that received 100 mg/kg (one leiomyoma of the small intestine, one adenocarcinoma of the jejunum, one leiomyoma of the cecum), 2/50 male rats that received 200 mg/kg (one lipoma and one osteosarcoma of the cecum), and 1/50 female rats that received 200 mg/kg (one leiomyoma of the cecum) were not considered to be the result of chemical exposure. No compound-related neoplasms were found in mice exposed to 2-amino-5-nitrophenol in the 2-year studies. Genetic Toxicology: 2-Amino-5-nitrophenol was mutagenic in Salmonella typhimurium strains TA98, TA100, and TA1537 when tested in a preincubation protocol with and without exogenous metabolic activation, and it exhibited equivocal mutagenic activity in strain TA1535 in the presence of induced liver S9. 2-Amino-5-nitrophenol induced forward mutations in mouse L5178Y lymphoma cells in the absence of metabolic activation; it was not tested with S9. An increase in chromosomal aberrations and sister chromatid exchanges was observed in cultured Chinese hamster ovary (CHO) cells following incubation with 2-amino-5-nitrophenol both in the presence and absence of exogenous metabolic activation. Data Audit: The data, documents, and pathology materials from the 2-year studies of 2-amino-5-nitrophenol were audited at the NTP Archives. The audit findings show that the conduct of the studies is documented adequately and support the data and results given in this Technical Report. Conclusions: Under the conditions of these 2-year gavage studies, there was some evidence of carcinogenic activity for male F344/N rats that received 100 mg/kg 2-amino-5-nitrophenol, as shown by the increased incidence of acinar cell adenomas of the pancreas. Reduced survival of male F344/N rats that received 200 mg/kg decreased the sensitivity of this group for detecting a carcinogenic response. There was no evidence of carcinogenic activity for female rats that received 100 or 200 mg/kg per day. Marginally increased incidences of preputial or clitoral gland adenomas or carcinomas (combined) occurred in male and female F344/N rats administered 200 mg/kg 2-amino-5-nitrophenol. There was no evidence of carcinogenic activity for B6C3F1 mice that received 400 mg/kg 2-amino-5-nitrophenol; reduced survival of B6C3F1 mice that received 800 mg/kg caused this group to be considered inadequate for detecting a carcinogenic response.
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PMID:NTP Toxicology and Carcinogenesis Studies of 2-Amino-5-Nitrophenol (CAS No. 121-88-0) in F344/N Rats and B6C3F1 Mice (Gavage Studies). 1273 2

Elf-1 is a member of the Ets transcription factor family that regulates the genes involved in cellular growth and differentiation. Enhanced expression of Elf-1 has been reported in prostate cancer, breast cancer, and osteosarcoma. The aim of this study was to elucidate the involvement of Elf-1 in ovarian carcinogenesis. We analyzed serial frozen tissue sections from 26 patients with epithelial ovarian carcinoma and 10 patients with benign cystadenoma of ovary for Elf-1 protein expression, using fluorescent immunohistochemistry. We analyzed the relationship between the percentages of Elf-1-stained cells and patient characteristics, including histological classification, clinical stage, histological grade, clinical outcome, and survival rate. Elf-1 was weakly detected in some benign cystadenomas (0-5.5%). There was, however, abundant Elf-1 immunoreactivity in the nucleus of the ovarian carcinoma cells along with a little cytoplasmic staining. Scoring on the basis of the percentage of nuclear-positive cells indicated that nuclear Elf-1 expression was significantly associated with PCNA-labeling index (p=0.04), clinical stage (p<0.01), histological grade (p<0.01), and clinical outcome (p=0.02). However, there was no relationship between Elf-1 expression and histological classification. Survival data were available for all patients and demonstrated that Elf-1 expression was significantly associated with poor prognosis (p<0.01). Our results demonstrate that Elf-1 expression in ovarian carcinoma correlates with the malignant potential of this tumor.
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PMID:The significance of Elf-1 expression in epithelial ovarian carcinoma. 1288 51

Lifetime bone tumor induction by the injection of a bone-seeking alpha emitter, 239Pu citrate, was compared among 630 female mice from three strains (C3H/He, C57BL/6 and B6C3F1) showing different genetic backgrounds for carcinogenesis. Bone tumors, mostly osteosarcomas, appeared early during the period from 200 to 600 days after the injection, showing an almost similar dose responsiveness with a peak incidence of 50% to 63% at skeletal doses of 2-3 Gy, in all mouse strains. The primary sites of bone tumors from these strains were also predominantly distributed in 80% to 90% of the skeletal bones, which had well-developed trabecular bone surfaces and large vascular sinusoids. The frequency of lymphoid neoplasms was significantly lower than the control values, and some appeared earlier at the higher injected doses than those of the controls. Fewer or no myeloid leukemias were found in all the control and injected animals, and the incidences of other solid tumors decreased, reaching zero at doses where the maximum incidences of bone tumors were noted. These findings indicate that osteosarcoma is the only specific tumor commonly observed among different mouse strains following the injection of soluble plutonium compounds.
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PMID:The specific induction of osteosarcomas in different mouse strains after injections of 239Pu citrate. 1367 41

p16(INK4a) (hereafter referred to as p16), a major cyclin-dependent kinase (CDK) inhibitor, is the product of a tumor-suppressor gene that has been found inactivated in different cancer types. In the present study, we sought to investigate the role of p16 in apoptosis induced by ultraviolet light (the most important etiological cause of skin cancer) and cisplatin (an anticancer DNA damaging agent). It is clearly shown that p16-compromised osteosarcoma U2OS cell line and p16-/- mouse embryo fibroblasts are sensitive to UV-induced apoptosis, as compared to their respective isogenic p16-expressing cells (EH1, EH2) and p16 +/+, indicating that p16 protects cells from undergoing apoptosis in response to UV light. Importantly, this reduction in UV-mediated apoptosis was associated with downregulation of the proapoptotic Bax protein, with no effect on Bcl-2 expression, suggesting that this antiapoptotic role of p16 is mediated via the intrinsic-mitochondrial pathway. On the other hand, p16 sensitized cells to cisplatin-mediated apoptosis through Bcl-2 decline. Interestingly, only proliferating but not G1-arrested EH1 cells underwent apoptosis in response to the anticancer drug. These novel findings provide further insight into the role of p16 in carcinogenesis, and has potential implications for future therapy strategies.
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PMID:The tumor suppressor p16(INK4a) gene is a regulator of apoptosis induced by ultraviolet light and cisplatin. 1471 25

The Wingless-type (Wnt) family of proteins and its coreceptor LRP5 have recently been implicated in human skeletal development. Wnt pathway modulates cell fate and cell proliferation during embryonic development and carcinogenesis through activation of receptor-mediated signaling. Osteosarcoma (OS) is a bone-forming tumor of mesenchymal origin whose growth control has been linked to autocrine or paracrine stimulation by several growth factor families. We examined 4 OS cell lines for WNT1, WNT4, WNT5A, WNT7A, WNT11, FZD1-10 and LRP5 expression by reverse transcription polymerase chain reaction (RT-PCR). In addition, RT-PCR for LRP5 expression was performed in 44 OS patient samples and the findings were correlated with clinical data. Expression profiling of Wnts and their receptors revealed the presence of several isoforms in OS cell lines. Overall, 22/44 (50%) of OS patient samples showed evidence of LRP5 expression. Presence of LRP5 correlated significantly with tumor metastasis (p = 0.005) and the chondroblastic subtype of OS (p = 0.045). In addition, patients whose tumors were positive for LRP5 showed a trend toward decreased event-free survival (p = 0.066). No significant association was found between LRP5 expression and age, gender, site of disease, site of metastasis or degree of chemotherapy-induced tumor necrosis. Sequencing of exon 3 of LRP5 in 10 OS patient-derived cell cultures showed no activating mutation of LRP5. These results showed that expression of LRP5 is a common event in OS and strongly suggest a role for LRP and Wnt signaling in the pathobiology and progression of this disease.
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PMID:Expression of LDL receptor-related protein 5 (LRP5) as a novel marker for disease progression in high-grade osteosarcoma. 1473 75

To establish a method for predicting the response to chemotherapy for osteosarcoma (OS), we performed expression profile analysis using cDNA microarray consisting of 23,040 genes. Hierarchical clustering based on the expression profiles of 19 biopsy samples of OS demonstrated two major clusters, one of which consisted exclusively of typical OS, i.e. conventional central OS in long bone of patients in the second decade. A set of genes was identified to characterize this subgroup, some of which have previously indicated some relation to carcinogenesis. Thirteen of the 19 patients were treated with an identical protocol of chemotherapy containing doxorubicin, cis-platinum and ifosfamide, and histological examination of resected specimens after operation classified 6 cases as responder and 7 as non-responder. A comparison of expression profiles of these two groups identified 60 genes whose expression levels were likely to be correlated with the response to chemotherapy (P<0.008). A drug response scoring (DRS) system was developed based on the expression levels of these genes, which proved to be applicable to predict the response to chemotherapy irrespective for the subclassification of OS. The reliability of the DRS system was further confirmed by testing additional 5 OS cases. These results indicated that scoring system based on gene-expression profiles might be useful to predict the response to chemotherapy for OS.
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PMID:Prediction of response to neoadjuvant chemotherapy for osteosarcoma by gene-expression profiles. 1476 49


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