Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Modern treatment has dramatically improved the prognosis for patients with polycythaemia vera (PV). Here a patient is described who has been followed and treated for PV for over 30 years, demonstrating that very long term survival can be achieved in PV. However, effective treatment modalities such as radioactive phosphorus, alkylating agents and, most recently, hydroxyurea, have all been shown to increase the risk to develop acute leukaemia when used in the treatment of myeloproliferative disorders. Hopefully, the prolonged survival of this patient may help to emphasize the need to use non-leukaemogenic agents when treating younger PV patients.
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PMID:Survival in a patient with polycythaemia vera for over thirty years: implications for treatment decisions in younger patients. 1003 17

31P NMR spectroscopy was used to study the products of the decomposition of the antitumor drug ifosfamide (IF, 1d) and its N-dechloroethylated metabolites, namely, 2,3-didechloroethylIF (1a) and 2- (1b) and 3-dechloroethylIF (1c), in buffered solutions at acidic pH. The first stage of acid hydrolysis of these four oxazaphosphorines is a P-N bond cleavage of the six-membered ring leading to the phosphoramidic acid monoesters (2a-d) of type R'HN(CH(2))(3)OP(O)(OH)NHR, with R and/or R' = H or (CH(2))(2)Cl. The electron-withdrawing chloroethyl group at the endocyclic and/or exocyclic nitrogens counteracts the endocyclic P-N bond hydrolysis. This effect is even more marked when the N-chloroethyl group is in the exocyclic position since the order of stability is 1d > 1c > 1b > 1a. In the second stage of hydrolysis, the remaining P-N bond is cleaved together with an intramolecular attack at the phosphorus atom by the non-P-linked nitrogen of the compounds 2a-d. This leads to the formation of a 2-hydroxyoxazaphosphorine ring with R = H (3a coming from compounds 2a,c) or (CH(2))(2)Cl (3b coming from compounds 2b,d) and to the release of ammonia or chloroethylamine. The third step is the P-N ring opening of the oxazaphosphorines 3a,b leading to the phosphoric acid monoesters, H(2)N(CH(2))(3)OP(O)(OH)(2) (4a) and Cl(CH(2))(2)HN(CH(2))(3)OP(O)(OH)(2) (4b-1), respectively. For the latter compound, the chloroethyl group is partially (at pH 5.5) or totally (at pH 7.0) cyclized into aziridine (4b-2), which is then progressively hydrolyzed into an N-hydroxyethyl group (4b-3). Compounds 3a,b are transient intermediates, which in strongly acidic medium are not observed with (31)P NMR. In this case, cleavage of the P-N bond of the type 2 phosphoramidic acid monoesters leads directly to the type 4 phosphoric acid monoesters. The phosphate anion, derived from P-O bond cleavage of these latter compounds, is only observed at low levels after a long period of hydrolysis. Compounds 1a-c and some of their hydrolytic degradation products (4b-1, 4b-2, diphosphoric diester [Cl(CH(2))(2)NH(CH(2))(3)OP(O)(OH)](2)O (5), and chloroethylamine) did not exhibit, as expected, any antitumor efficacy in vivo against P388 leukemia. (31)P NMR determination of the N-dechloroethylated metabolites of IF or its structural isomer, cyclophosphamide (CP), and their degradation compounds could provide an indirect and accurate estimation of chloroacetaldehyde amounts formed from CP or IF.
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PMID:Chemical stability and fate of the cytostatic drug ifosfamide and its N-dechloroethylated metabolites in acidic aqueous solutions. 1041 75

Photodynamic therapy (PDT), a cancer treatment already used early in this century, has distinctive advantages over conventional chemotherapy, namely its often observed preferential accumulation in cancer cells and its low intrinsic toxicity. Aggressive therapeutic modalities using high doses of chemotherapy and/or radiation therapy are now commonplace treatments for leukaemia, lymphoma and various non-haematologic malignancies. These intensive approaches have often been used in association with haematopoietic-progenitor-cell support and have induced major responses and remissions in patients with relapsed and refractory diseases, ultimately contributing to improve the disease-free survival of patients with high risk. This has encouraged Theratechnologies, a Montreal-based pharmaceutical company, to develop photodynamic ex vivo purging procedures, including the development of new photosensitizers and irradiation devices for the safe eradication of neoplastic cells from autologous grafts. Our first specific objective, therefore, was to design, synthesize, purify and test photoactive rhodamine derivatives. We have also selected a gas and phosphorus coating characteristic of an efficient scanning fluorescent source for extra-corporeal PDT using rhodamine derivatives. 4,5-Dibromorhodamine 123 (TH9402) was selected because of its photophysical properties, low toxicity and stability. TH9402 photodynamic-cell-therapy process conditions recognized as safe for normal human haematopoietic stem cells and progenitors demonstrated the efficacy of the purging procedure on various leukaemias (including chronic-myelogenous-leukaemia as well as non-Hodgkin-leukaemias and metastatic-breast-cancer cell lines.
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PMID:Ex vivo photodynamic purging in chronic myelogenous leukaemia and other neoplasias with rhodamine derivatives. 1046 13

Essential thrombocythaemia (ET) is a clonal stem cell disorder that frequently presents as an incidental finding of elevated platelet counts. Diagnosis depends on exclusion of other myeloproliferative disorders and reactive thrombocytosis. Patients with platelet counts above 1000 x 10(9)/L should receive platelet-lowering therapy, even if asymptomatic. Definitive recommendations cannot yet be made for asymptomatic patients with lower platelet counts. ET can be treated with alkylating agents, radioactive phosphorus or hydroxyurea, but there is evidence that these agents increase transformation to acute leukaemia. Interferon alfa-2a and anagrelide are useful treatment agents, particularly in younger patients.
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PMID:Essential thrombocythaemia. 1049 40

We report an unusual case of congenital leukemia with leukemia cutis (LC) and diffuse calcinosis cutis. A newborn girl presented with widespread dusky red and yellowish cutaneous nodules and papules. Bone marrow morphology was consistent with the diagnosis of acute monocytic leukemia of the FAB M5 type. Skin biopsy specimens confirmed the presence of a leukemic infiltrate and revealed calcium salt deposition in the papillary and reticular dermis. Calcinosis was diffuse in the whole skin but spared other organs. Vascular calcification was not present. Serum calcium levels oscillated between 2.5 and 2.86 mmol/l, and phosphorus, parathyroid hormone and 25-hydroxyvitamin D(3) levels were normal. There were diffuse osteoporosis and spontaneous fractures of small tubular bones. The patient responded to chemotherapy but, following consolidation treatment, developed sepsis and died at 120 days of age. Congenital leukemia is rare and LC is uncommon. Hypercalcemia may be a complication of leukemia, which leads to multiorgan metastatic calcification. Despite the absence of frank hypercalcemia, the presence of bone lesions suggests that the patient's calcinosis cutis was of the metastatic type. However, the cutaneous leukemic infiltrate may also represent a triggering factor for calcium deposition in the skin.
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PMID:Diffuse calcinosis cutis in a patient with congenital leukemia and leukemia cutis. 1077 6

Here we report the synthesis and characterization of a lipophilic phosphatidylcholine containing the omega-3 fatty acid docosahexaenoic acid (DHA) and the cytotoxic drug methotrexate (MTX). This novel phospholipid combines the fatty acid's and the drug's anticancer activities in a molecule amenable to a liposome bilayer for safe, simultaneous delivery of the two agents. Two phosphatidylcholines were synthesized, from 1-stearoyl or 1-docosahexaenoyl, 2-hydroxy-sn-glycero-3-phosphocholine, to contain MTX in the sn-2 position and either stearic acid or DHA in the sn-1 position. The products contain fatty acid, MTX and phosphorus (1:1:1), and the MTX was released by phospholipase A(2), consistent with the proposed phospholipid structure. The predominant product linked MTX to the glycerol moiety through MTX's gamma-carboxyl group. Liposomes composed of 1-stearoyl, 2-oleoyl phosphatidylcholine plus 1-stearoyl, 2-oleoyl phosphatidylethanolamine and various concentrations of the novel phospholipids caused dose-dependent inhibition of murine leukemia cell proliferation in culture. The DHA- and MTX-containing phosphatidylcholine was more effective than that containing stearic acid, and DHA appeared to synergize with MTX when they were added as free agents or covalently linked in the phospholipid. These data show the feasibility of synthesizing, and the inhibitory activity of phosphatidylcholine with DHA in the sn-1 position and MTX in the sn-2 position, and suggest the compound's potential use in cancer chemotherapy.
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PMID:Synthesis of a novel phosphatidylcholine conjugated to docosahexaenoic acid and methotrexate that inhibits cell proliferation. 1198 74

Barium chloride dihydrate, a white crystalline granule or powder, is used in pigments, aluminum refining, leather tanning and coloring, the manufacture of magnesium metal, ceramics, glass, and paper products, as a pesticide, and in medicine as a cardiac stimulant. Toxicology and carcinogenicity studies were conducted by administering barium chloride dihydrate (99% pure) in drinking water to F344/N rats and B6C3F1 mice for 15 days, 13 weeks, and 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, cultured Chinese hamster ovary cells, and mouse lymphoma cells. 15-DAY STUDY IN RATS: Groups of five males and five females received barium chloride dihydrate in the drinking water at concentrations of 0, 125, 250, 500, 1,000, or 2,000 ppm for 15 days, corresponding to average daily doses of 10, 15, 35, 60, or 110 mg barium/kg body weight to males and females. No chemical-related deaths, differences in final mean body weights, or clinical findings of toxicity were observed. Water consumption by male and female rats exposed to 2,000 ppm was slightly less (S16%) than controls during week 2. There were no significant differences in absolute or relative organ weights between exposed and control rats. No biologically significant differences in hematology, clinical chemistry, or neurobehavioral parameters occurred in rats. 15-DAY STUDY IN MICE: Groups of five males and five females received barium chloride dihydrate in the drinking water at concentrations of 0, 40, 80,173, 346, or 692 ppm for 15 days, corresponding to average daily doses of 5,10, 20, 40, or 70 mg barium/kg body weight to males and 5, 10, 15, 40, or 85 mg barium/kg body weight to females. No chemical-related deaths, differences in mean body weights or in water consumption, or clinical findings of toxicity were observed in mice. The relative liver weight of males receiving 692 ppm was significantly greater than that of the controls. The absolute and relative liver weights of females that received 692 ppm were significantly greater than those of the controls. No histopathologic evidence of toxicity was observed in mice. 13-WEEK STUDY IN RATS: Groups of 10 males and 10 females received barium chloride dihydrate in the drinking water at concentrations of 0, 125, 500, 1,000, 2,000, or 4,000 ppm for 13 weeks, corresponding to average daily doses of 10, 30, 65, 110, or 200 mg barium/kg body weight to males and 10, 35, 65, 115, or 180 mg barium/kg body weight to females. Three males and one female in the 4,000 ppm groups died during the last week of the study. The final mean body weights of male and female rats receiving 4,000 ppm were significantly lower (13% and 8%) than those of the controls. Water consumption by male and female rats in the 4,000 ppm groups was approximately 30% lower than that by the controls. No clearly chemical-related clinical findings of toxicity or neurobehavioral or cardiovascular effects were noted. Serum phosphorus levels in 2,000 and 4,000 ppm male and female rats were significantly higher than those in controls, but there were no biologically significant differences in hematology parameters or in serum sodium, potassium, or calcium levels. Renal tubule dilatation in the outer stripe of the outer medulla and cortex occurred in male and female rats receiving 4,000 ppm. 13-WEEK STUDY IN MICE: Groups of 10 males and 10 females received barium chloride dihydrate in the drinking water at concentrations of 0, 125, 500, 1,000, 2,000, or 4,000 ppm for 13 weeks, corresponding to average daily doses of 15, 55, 100, 205, or 450 mg barium/kg body weight to males and 15, 60, 110, 200, or 495 mg barium/kg body weight to females. Six males and seven females that received 4,000 ppm and one male that received 125 ppm died during the study. Final mean body weights of male and female mice receiving 4,000 ppm were significantly lower (>30%) than those of controls. Water consumption by male mice in the 4,000 ppm group was 18% lower than that by the controls; water consumption by other exposed groups of male and female mice was similar to thatd groups of male and female mice was similar to that by the controls. Clinical findings of toxicity were limited to debilitation in the surviving male and female mice receiving 4,000 ppm. The absolute and/or relative liver weights of mice receiving 1,000, 2,000, and 4,000 ppm were significantly lower than those of the controls. Multifocal to diffuse nephropathy characterized by tubule dilatation, regeneration, and atrophy occurred in 4,000 ppm male and female mice. 2-YEAR STUDY IN RATS: Groups of 60 males and 60 females received barium chloride dihydrate in the drinking water at concentrations of 0, 500, 1,250, or 2,500 ppm for 104 (males) or 105 weeks (females), corresponding to average daily doses of 15, 30, or 60 mg barium/kg body weight for males and 15, 45, or 75 mg barium/kg body weight for females. The high dose of 2,500 ppm was selected based on decreased final mean body weights, mortality, decreased water consumption, and chemical-related kidney lesions observed in the 4,000 ppm groups in the 13-week study. Survival, Body Weights, Water Consumption, and Clinical Findings: Two-year survival of exposed male and female rats was similar to that of the controls. The final mean body weights of male and female rats that received 2,500 ppm were (5% and 11%) lower than those of controls. Beginning as early as week 5, water consumption by male and female rats receiving 2,500 ppm was substantially lower than that by controls (male: 11% to 30%; female: 19% to 33%). There were no chemical-related clinical findings. Hematology and Clinical Chemistry: There were no chemical-related differences in hematology or clinical chemistry parameters in male or female rats. Special Studies: At the 15-month interim evaluation, the plasma barium concentrations (mg/ml) were significantly increased in males receiving 1,250 and 2,500 ppm and in all exposed groups of females (male: 0 ppm, 0.98; 500 ppm, 1.00; 1,250 ppm, 1.23; 2,500 ppm, 1.68; female: 0 ppm, 0.74; 500 ppm, 0.99; 1,250 ppm, 0.97; 2,500 ppm, 1.43). Barium levels in bone in rats from the 2,500 ppm groups were about 400 times greater than those in the controls. Pathology Findings: At the end of 2 years, there were no increased incidences of neoplasms or nonneoplastic lesions that could be attributed to barium chloride dihydrate. However, there were dose-related decreased incidences of adrenal medulla pheochromocytomas and mononuclear cell leukemia in male rats. 2-YEAR STUDY IN MICE: Groups of 60 males and 60 females received barium chloride dihydrate in the drinking water at concentrations of 0, 500, 1,250, or 2,500 ppm for 103 (males) or 104 weeks (females), corresponding to average daily doses of 30, 75, or 160 mg barium/kg body weight for males and 40, 90, or 200 mg barium/kg body weight for females. The high dose of 2,500 ppm was selected based on decreased final mean body weights, mortality, decreased water consumption, and chemical-related kidney lesions observed in the 4,000 ppm groups in the 13-week study. Survival, Body Weights, Water Consumption, and Clinical Findings: Two-year survival of male and female mice receiving 2,500 ppm was significantly lower than that of the controls due to renal toxicity. Final mean body weights of 2,500 ppm males and females were 9% and 12% lower than those of controls. Water consumption by male and female mice receiving barium chloride was similar to that by the controls. There were no chemical-related clinical findings. Hematology and Clinical Chemistry: There were no differences in hematology or clinical chemistry parameters measured at the 15-month interim evaluation. Special Studies: At the 15-month interim evaluation, plasma barium concentrations (mg/mL) were significantly increased in all exposed groups of mice (male: 0 ppm, 0.62; 500 ppm, 0.77; 1,250 ppm, 0.89; 2,500 ppm, 1.49; female: 0 ppm, 0.52; 500 ppm, 0.74; 1,250 ppm, 1.01; 2,500 ppm, 1.35). Pathology Findings: At the end of the 2-year study, there were increased incidences of nephropathy in male and female mice (male: 1/50, 0/50, 2/48, 19/50; female: 0/50, 2/53, 1/50, 37/54). There were no chemical-related increased incidences of neoplasms in male or female mice. The incidence of hepatocellular adenoma was significantly decreased in male mice receiving 2,500 ppm. GENETIC TOXICOLOGY: Barium chloride dihydrate was not mutagenic in Salmonella typhimurium strains TA97, TA98, TA100, TA1535, or TA1537, with or without exogenous metabolic activation (S9). It was mutagenic in L5178Y mouse lymphoma cells in the presence of S9, but it did not induce sister chromatid exchanges or chromosomal aberrations in cultured Chinese hamster ovary cells, with or without S9. CONCLUSIONS: Under the conditions of these 2-year drinking water studies, there was no evidence of carcinogenic activity of barium chloride dihydrate in male or female F344/N rats that received 500, 1,250, or 2,500 ppm. There was no evidence of carcinogenic activity of barium chloride dihydrate in male or female B6C3F1 mice that received 500, 1,250, or 2,500 ppm. There were chemical-related increased incidences of nephropathy in male and female mice.
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PMID:NTP Toxicology and Carcinogenesis Studies of Barium Chloride Dihydrate (CAS No. 10326-27-9) in F344/N Rats and B6C3F1 Mice (Drinking Water Studies). 1261 99

Furan serves as an intermediate in the synthesis and preparation of numerous linear polymers used to prepare temperature-resistant structural laminates and to prepare copolymers used in machine dishwashing products as alternatives to phosphorus- and nitrogen-containing detergents. Toxicology and carcinogenesis studies were conducted by administering furan (purity > 99%) in corn oil by gavage to groups of F344/N rats and B6C3F1 mice of each sex for 16 days, 13 weeks, and 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, Drosophila melanogaster, mouse bone marrow cells, mouse L5178Y lymphoma cells, and Chinese hamster ovary cells. 16-Day Studies: Groups of five male rats received doses of 0, 5, 10, 20, 40, or 80 mg of furan per kg of body weight and groups of five female rats and five mice of each sex received doses of 0, 10, 20, 40, 80, and 160 mg/kg in corn oil by gavage. All male and female mice and female rats that received 160 mg/kg, all male and female rats and all male and four female mice that received 80 mg/kg, and three male mice that received 40 mg/kg died by day 8. Final mean body weights of male rats that received 20 mg/kg and of male and female rats that received 40 mg/kg were significantly lower than controls. Final mean body weights of male mice that received 10 or 20 mg/kg were significantly greater than controls. Mottled and enlarged livers were observed at necropsy in male rats that received 20, 40, or 80 mg/kg and in females that received 40, 80, or 160 mg/kg. No lesions were observed at necropsy that were considered related to furan administration in mice. 13-Week Studies: Groups of 10 rats of each sex and groups of 10 female mice received doses of 0, 4, 8, 15, 30, or 60 mg of furan per kg of body weight, and groups of 10 male mice received doses of 0, 2, 4, 8, 15, or 30 mg/kg in corn oil by gavage. Nine male and four female rats that received 60 mg/kg died before the end of the studies. There were no chemical-related deaths in mice. Final mean body weights of male rats that received 15 or 30 mg/kg and female rats that received 60 mg/kg were significantly lower than controls. Final mean body weights of male mice that received 60 mg/kg were significantly lower than controls. Relative and absolute liver weights in both sexes of rats and mice were increased in groups that received furan, as were relative and absolute kidney weights in female rats that received furan. Thymus weights were decreased in all groups of rats that received furan. Toxic lesions of the liver (bile duct hyperplasia, cholangiofibrosis, cytomegaly and degeneration of hepatocytes, and nodular hyperplasia of hepatocytes) were associated with furan administration in all dose groups of rats; the severity of the lesions increased with dose. Kidney lesions (tubule dilatation and necrosis of tubule epithelium) were present in rats that received 30 or 60 mg/kg. Thymic atrophy and testicular or ovarian atrophy were also observed in rats exposed to 60 mg/kg furan. Toxic liver lesions (cytomegaly, degeneration, and necrosis of hepatocytes) were also present in all groups of furan-exposed mice. Bile duct hyperplasia and cholangiofibrosis were observed in groups of mice receiving 30 or 60 mg/kg. Doses selected for the 2-year studies of rats and mice were based on the hepatotoxicity associated with exposure to furan. 2-Year Studies: Groups of 70 rats of each sex were administered 2, 4, or 8 mg furan per kg body weight in corn oil by gavage 5 days per week for 2 years. After 9 and 15 months of chemical exposure, 10 rats per group were evaluated for the presence of treatment-associated lesions. Groups of 50 mice of each sex received doses of 8 or 15 mg/kg furan 5 days per week for 2 years. Body Weight and Survival: Mean body weights of male rats that received 8 mg/kg furan were lower than controls from approximately week 73 to the end of the study. Survival of male and female rats that received 8 mg/kg was lower than controls from approximately week 85 to the end of the studies as a result of moribund condition associatedassociated with liver and biliary tract neoplasms and mononuclear cell leukemia. Mean body weights of male and female mice that received 15 mg/kg furan were lower than controls during the studies. Survival of low- and high-dose male and high-dose female mice was lower than controls from approximately week 80 to the end of the studies as a result of moribund condition associated with liver neoplasms. Neoplastic and Nonneoplastic Lesions: Cholangiocarcinoma of the liver occurred in all groups of dosed rats (males: control, 0/50; low dose, 43/50; mid dose, 48/50; high dose, 49/50; females: 0/50; 49/50; 50/50; 48/50) and was present in many rats of each sex at the 9- and 15-month interim evaluations (9-month: males - 0/10, 5/10, 7/10, 10/10; females - 0/10, 4/10, 9/10, 10/10; 15-month: males - 0/10, 7/10, 9/10, 6/10; females - 0/10, 9/10, 9/10, 7/10). Hepatocellular adenomas or carcinomas (combined) were significantly increased in male rats after 2 years of chemical administration (1/50, 5/50, 22/50, 35/50) and hepatocellular adenomas were significantly increased in female rats (0/50, 2/50, 4/50, 7/50); hepatocellular neoplasms were not observed at the 9- or 15-month interim evaluations. Increased incidences of numerous nonneoplastic liver lesions were present in rats administered furan. These lesions included biliary tract fibrosis, hyperplasia, chronic inflammation, and proliferation and hepatocyte cytomegaly, cytoplasmic vacuolization, degeneration, nodular hyperplasia, and necrosis. The incidence of mononuclear cell leukemia was increased in male and female rats that received 4 or 8 mg/kg furan (males: 8/50, 11/50, 17/50, 25/50; females: 8/50, 9/50, 17/50, 21/50); the incidence in the 8 mg/kg groups of each sex exceeded the historical control ranges for corn oil gavage studies. The severity of nephropathy increased with dose and the incidence was significantly increased in all groups of dosed rats; this increased severity was accompanied by an associated increased incidence of parathyroid hyperplasia (renal secondary hyperparathyroidism). The incidence of forestomach hyperplasia was increased in male and female rats (males: 1/50, 4/49, 7/50, 6/50; females: 0/50, 2/50, 5/50, 5/50) and the incidence of subacute inflammation of the forestomach was increased in female rats (0/50, 1/50, 5/50, 6/50). No forestomach neoplasms were observed in males; a squamous papilloma was present in one low-dose female. The incidences of hepatocellular adenomas and carcinomas were significantly increased in mice receiving furan (males: adenoma - 20/50, 33/50, 42/50; carcinoma - 7/50, 32/50, 34/50; females: adenoma - 5/50, 31/50, 48/50; carcinoma - 2/50, 7/50, 27/50). The incidences of numerous nonneoplastic hepatocellular lesions were increased in dosed mice. These lesions included hepatocyte cytomegaly, degeneration, necrosis, multifocal hyperplasia, and cytoplasmic vacuolization and biliary tract dilatation, fibrosis, hyperplasia, and inflammation. The incidences of benign pheochromocytoma and focal hyperplasia of the adrenal medulla were increased in low- and high-dose male and in high-dose female mice (benign pheochromocytoma: males - 1/49, 6/50, 10/50; females - 2/50, 1/50, 6/50). The incidences of squamous papilloma, focal inflammation, and papillary hyperplasia of the forestomach were increased in male mice (squamous papilloma: 0/49, 1/50, 3/50; focal inflammation: 9/49, 13/50, 21/50; papillary hyperplasia: 7/49, 14/50, 22/50). Stop-Exposure Study: A separate 2-year study was conducted in which 50 male rats were administered 30 mg/kg furan in corn oil by gavage 5 days per week for 13 weeks and then maintained for the remainder of the 2 years without additional furan administration. Groups of 10 animals were evaluated for the presence of treatment-related lesions at the end of the 13-week period of furan administration and at 9 and 15 months. Neoplastic and Nonneoplastic Lesions: Cholangiocarcinoma of the liver occurred with an overall incidence of 100% (40/40) and hepatocellular carcinoma occurred with an overall incidence of 15% (6/40) in stop-exposure male rats that survived at least 9 months. Cholangiocarcinoma was observed in all 10 males at both the 9-month and 15-month interim evaluations. Hepatocellular carcinoma was first observed in 2 males at the 15-month interim evaluation. Genetic Toxicology: Furan was negative for induction of gene mutations in Salmonella typhimurium strains TA100, TA1535, TA1537, and TA98 in the presence and the absence of exogenous metabolic activation (S9). Furan was negative for the induction of sex-linked recessive lethal mutations in germ cells of male Drosophila melanogaster when administered either by feeding or by injection. In vitro tests for genotoxicity in mammalian cells, however, were positive. Furan induced trifluorothymidine resistance in mouse L5178Y lymphoma cells in the absence of S9, and sister chromatid exchanges and chromosomal aberrations in Chinese hamster ovary cells, with and without S9. Furan administered to male B6C3F1 mice by intraperitoneal injection induced chromosomal aberrations but not sister chromatid exchanges in bone marrow cells. Conclusions: Under the conditions of these 2-year gavage studies there was clear evidence of carcinogenic activity of furan in male and female F344/N rats based on increased incidences of cholangiocarcinoma and hepatocellular neoplasms of the liver and on increased incidences of mononuclear cell leukemia. There was clear evidence of carcinogenic activity of furan in male and female B6C3F1 mice based on increased incidences of hepatocellular neoplasms of the liver and benign pheochromocytomas of the adrenal gland. Nonneoplastic liver lesions associated with furan administration in rats and mice included biliary tract fibrosis, hyperplasia, inflammation, and proliferation, as well as hepatocellular cytomegaly, degeneration, hyperplasia, necrosis, and vacuolization. In rats, increased severity of nephropathy with an associated increased incidence of parathyroid hyperplasia was associated with exposure to furan. Synonyms: Divinylene oxide, tetrole, furfuran, oxole, 1,4-epoxy-1,3-butadiene, axole, oxacyclopentadiene
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PMID:Toxicology and Carcinogenesis Studies of Furan (CAS No. 110-00-9) in F344 Rats and B6C3F1 Mice(Gavage Studies). 1262 16

A new series of 1-(6-chloro-1,1-dioxo-1,4,2-benzodithiazin-3-yl)-4-arylsemicarbazides (4-16) were obtained. Intramolecular ring closure in semicarbazides 4-16 upon treatment with phosphorus oxychloride resulted in the formation of 2-amino-8-chloro-5,5-dioxo[1,2,4]triazolo[2,3-b][1,4,2]benzodithiazines 17-29 with potential antitumor activity. The structures of these compounds were confirmed on the basis of elemental analysis, spectral data and X-ray analysis. Compounds 17-29 were screened at the US National Cancer Institute (NCI) for their activities against a panel of 59 tumor cell lines, and relationships between structure and antitumor activity in vitro are discussed. The benzodithiazines 18, 19, 23, 28 and 29 were inactive, whereas the other compounds exhibited reasonable activity against numerous human tumor cell lines. The prominent compound 17 showed significant activity against the leukemia SR cell line (log GI(50)=-7.67, log TGI=-6.90 and log LC(50)=-4.77).
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PMID:Synthesis and anticancer activity of 2-amino-8-chloro-5,5-dioxo[1,2,4]triazolo[2,3-b][1,4,2]benzodithiazine derivatives. 1262 53

The risk of development of cancer, and more specifically acute leukaemia, after use of phosphorus-32 in patients with polycythaemia vera has been recognised for approximately 40 years. As a consequence of this risk, the indications for, and contraindications to, 32P are unclear in the physician's mind. This paper aims to clarify the problem. The relation between polycythaemia vera and leukaemia is explored and the question of whether chemotherapy represents an alternative to 32P is discussed. From the results obtained to date, two clear conclusions can be drawn: First, whatever the age of the patient, phlebotomy must be used to avoid the menace of vascular complications before the institution of basic treatment, but it cannot be used as the sole form of treatment. Second, 32P treatment retains an important role at least when chemotherapy fails and in elderly patients (>70 years).
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PMID:Use and risks of phosphorus-32 in the treatment of polycythaemia vera. 1295 83


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