Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0007097 (carcinoma)
 152,788 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Biochemical modulation, which is more effective with the use of antitumor agents, has recently played very important role in cancer chemotherapy. In this review, it was reported that some of the methylxanthine derivatives, e.g. caffeine, were useful for modulator and attempted to defined the relation between the effect of methylxanthine derivatives on the doxorubicin transport and antitumor activity. Caffeine and theobromine inhibited the doxorubicin efflux from tumor cells, increased the doxorubicin concentration in a tumor, and enhanced the antitumor effect of doxorubicin. However, the caffeine metabolites, which had no effect on the doxorubicin efflux, did not increase antitumor activity. Moreover, caffeine and theobromine did not enhance the side toxicity of doxorubicin on the lipid peroxide level, DNA biosynthesis and the doxorubicin concentrations in normal tissues. Moreover, we investigated the effect of the combination of doxorubicin with caffeine or theobromine on the change in cyclic adenosine 3',5'-monophosphate (cyclic AMP) in tissues in vivo, and the effect of cyclic AMP on doxorubicin efflux in vitro, and measured the distribution of caffeine and theobromine in normal and tumor tissues. In Ehrlich ascites carcinoma bearing mice, the level of cyclic AMP in a tumor was decreased by doxorubicin. With the combination of caffeine or theobromine and doxorubicin, the cyclic AMP level recovered to the control level. This tendency was not seen in normal tissues (heart and liver). Moreover, the doxorubicin efflux from the Ehrlich cells was inhibited on the addition of cyclic AMP in vitro. And the caffeine concentration in the tumors was the same as that in the heart, and was increased in combination with doxorubicin compared with that in the caffeine-only group during the 4 hr after caffeine treatment. Furthermore, the doxorubicin efflux was promoted by the supply of energy (addition of glucose), influx was decreased relatively, doxorubicin efflux needs the existence of glucose and the inhibition of energy related drug export pump by caffeine induced inhibition of doxorubicin efflux. The treatment of doxorubicin nor caffeine, and any treatment schedule did not change the amount and appearance of GLUT 1 as glucose transporter on Ehrlich ascites carcinoma cell. For the mentioned above, we thought as concerns the increase of antitumor activity of doxorubicin by caffeine which is xanthine derivatives as follows. Caffeine distributes, high level in tumor, keeps the cyclic AMP level, and effects glucose transport or doxorubicin transport depend on energy and inhibits doxorubicin efflux. And then DNA synthesis was increased with the maintenance the concentration of doxorubicin in tumor. These action did not show in normal tissues, caffeine did not influence the side toxicity of doxorubicin. These results suggested that caffeine which is one of xanthine derivatives will be useful for biochemical modulator.
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PMID:Effect of methylxanthine derivatives on doxorubicin transport and antitumor activity. 1176 89

Long-term administration of caffeine at a dose of 20 mg /kg/day p.o. suppressed the viability, oxygen consumption and [3H]-thymidine incorporation of Ehrlich ascites carcinoma (EAC) cells. Though no significant change in the levels of plasma and adrenal corticosterone as well as both total and reduced adrenal ascorbic acid were observed following long-term caffeine consumption, pretreatment of caffeine and continuation of its treatment in the course of development of EAC cells restored the EAC Cell-induced changes in both corticosterone and ascorbic acid levels to control values. These results, thus, suggest that caffeine may suppress the growth of EAC cells by modulating the adrenal ascorbate level as well as corticosterone status.
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PMID:Caffeine inhibits the development of Ehrlich ascites carcinoma cells in female mice. 1201 73

Irinotecan (CPT-11), a recently introduced component of a standard chemotherapy for colorectal cancer, induces in colon cancer cell lines in vitro cell cycle arrest and apoptosis. Since sporadic colon carcinomas exhibit in 50-60% mutations in the p53 gene and in 10-15% an MSI phenotype due in the great majority of the cases to hMLH1 inactivation, we investigated how these lesions influence the cellular effects of CPT-11 by using colorectal carcinoma cell line HCT116 (which has the genotype p53(+/+),hMLH1(-)) and 2 derivative cell lines with the genotypes p53(+/+),hMLH1(+) and p53(-/-),hMLH1(-). CPT-11 treatment induced G2/M arrest in all 3 cell lines within 48 hr. In the p53(+/+),hMLH1(+) cell line, G2/M arrest was maintained for at least 12 days. There was little concomitant apoptosis, but this was enhanced when the hMLH1 protein was absent. This enhanced apoptosis was accompanied by a shorter duration of the G2/M arrest than in the hMLH1(+) cell line. Partial abrogation of G2/M arrest by caffeine enhanced apoptosis in both hMLH1(+) and hMLH1(-) cells. By contrast, in the p53(-/-) cell line, the G2/M arrest was terminated within 4 days. Termination of the G2/M arrest was accompanied by a high level of apoptosis detectable through poly(ADP-ribose)polymerase (PARP) cleavage, DNA fragmentation and by the appearance of cells with a DNA content <2N. The triggering of G2/M arrest was accompanied in the 3 cell lines by a transient phosphorylation of cdc-2, while the maintenance of the arrest in the p53(+/+) cell lines was accompanied by the overexpression of p53 and p21 proteins and, consequently, by the inhibition of cdc-2 kinase activity. These data indicate that: (i) CPT-11 induces long-term arrest in p53(+/+) cells and a short-term arrest followed by apoptosis in p53(-/-) cells; (ii) triggering of the arrest is p53 independent and is associated with a brief increase of phosphorylation of cdc-2, while the p53-dependent maintenance of G2/M arrest is associated with the inhibition of cdc-2 kinase activity by p21; and (iii) lack of hMLH1 protein enhances CPT-11-induced apoptosis. These results may be useful for designing rational therapies dependent on the p53 and mismatch-repair status in the tumor.
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PMID:Cellular effects of CPT-11 on colon carcinoma cells: dependence on p53 and hMLH1 status. 1220 84

The effect of the broad-spectrum anticancer agent, cisplatin, on the expression of DNA ligase I in human pancreatic carcinoma MiaPaCa cells was examined in this study, since DNA ligase I is known to be involved in various DNA repair pathways. Upon exposure of MiaPaCa cells to cisplatin at near IC(50) value (2.5-5 microM), about 2-3-fold increase of DNA ligase I levels was observed within 24h, while levels of other DNA ligases (III and IV) remained unchanged or slightly decreased. The same fold-increase in DNA ligase I levels was also observed in MiaPaCa cells exposed to cytostatic concentrations, but not cytotoxic concentrations of cisplatin, which significantly reduced the number of cells. Flow cytometric analysis revealed that normal cell cycle progression was disrupted in the cells treated with cisplatin, resulting in an initial arrest of the cells in the S-phase, concomitant with a decrease of cells in G0/G1-phase. With time elapsing, the transition from S- to G2 + M-phase was observed, but further progression into G0/G1-phase was blocked. Overall, the increase of DNA ligase I expression seems to correlate well with the arrest of the cell cycle between the S- and G2-phases in response to cisplatin treatment. Interestingly, the cisplatin-induced DNA ligase I increase was abrogated by caffeine treatment in MiaPaCa cells, suggesting that caffeine sensitive kinases might be important mediators in the pathway, leading to the increase of DNA ligase I levels in response to cisplatin. We propose that the increase of DNA ligase I expression after exposure to cisplatin might be required for aiding the cells to recover from the damage by facilitating the repair process.
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PMID:Effects of cisplatin on expression of DNA ligases in MiaPaCa human pancreatic cancer cells. 1240 85

Theophylline is an alkaloid found in tea (Thea sinensis) and chocolate and is structurally related to caffeine and theobromine. Theophylline is used as a pharmaceutical agent. It stimulates the heart and central nervous system, relaxes the smooth muscles of the bronchi and blood vessels, and causes diuresis. The drug is used mainly as a bronchodilator in obstructive airway diseases, such as bronchial asthma, and for myocardial stimulation. Theophylline was nominated for toxicologic and carcinogenicity testing as a representative of the purine structural subclass, particularly because of its relationship to purines such as caffeine, 1-methyl-3-hydroxyguanine, and 3-hydroxy-1-methylxanthine, the latter two compounds having been shown to induce sarcomas in rats. Additional reasons for testing theophylline included its widespread use in humans as a pharmaceutical agent, its possible genotoxicity in vitro, and the lack of information on its potential toxicity and/or carcinogenicity under conditions of chronic oral usage. Based on reported teratogenicity and testicular toxicity, it was also recommended that reproductive studies be included in the evaluation of theophylline. The oral route of administration was selected because it is the primary route of human exposure, and the gavage route was selected because it mimics the pharmaceutical use of theophylline in humans. Male and female F344/N rats and B6C3F1 mice were given theophylline (greater than 99% pure) in feed or in corn oil by gavage for 16 days or 14 weeks or in corn oil by gavage for 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, cultured Chinese hamster ovary cells, mouse bone marrow, and mouse peripheral blood. 16-DAY FEED STUDY IN RATS: Groups of five male and five female F344/N rats were given 0, 500, 1,000, 2,000, 4,000, or 8,000 ppm theophylline in feed for 16 days, which resulted in approximate daily doses of 50, 100, 250, 450, or 1,000 mg theophylline/kg body weight to males and 75, 150, 250, 450, or 1,100 mg/kg to females. All rats survived until the end of the study. The final mean body weights and body weight gains of 8,000 ppm males and females were significantly less than those of the controls. The absolute and relative testis weights of 4,000 ppm males were significantly greater than those of the controls. Increased incidences of uterine hypoplasia were observed microscopically in exposed groups of females. 16-DAY GAVAGE STUDY IN RATS: Groups of five male and five female F344/N rats were given 0, 12.5 (twice daily), 25 (once daily), 50 (once daily), 50 (twice daily), 100 (once daily), 200 (once daily), 200 (twice daily), or 400 (once daily) mg theophylline/kg body weight in corn oil by gavage. All rats receiving 400 mg/kg once daily and all but one female receiving 200 mg/kg twice daily died during the study. In groups dosed once daily, final mean body weights and body weight gains of males receiving 100 or 200 mg/kg and mean body weight gains of females receiving 50, 100, or 200 mg/kg were less than those of controls. The final mean body weights and body weight gains of groups receiving theophylline twice daily were generally similar to those of groups receiving the same daily dosages once daily. Clinical findings included rapid or labored respiration, hunched posture, and squinting. In groups dosed once daily, absolute and relative uterus weights of females receiving 100 or 200 mg/kg once daily were significantly less than those of the controls, and the absolute and relative uterus weights of females receiving 100 mg/kg once daily were significantly less than those of females receiving 50 mg/kg twice daily. Uterine atrophy was observed in three females receiving 200 mg/kg twice daily. Periarteritis of the mesenteric arteries was observed in two males and two females receiving 400 mg/kg once daily. 16-DAY FEED STUDY IN MICE: Groups of five male and five female B6C3F1 mice were given 0, 500, 1,000, 2,000, 4,000, or 8,000 ppm theophylline in feed for 16 days, resulting in approximate daily doses of 250, 475, 950, 1,800, or800, or 2,000 mg theophylline/kg body weight to males and 300, 450, 1,225, 2,000, or 4,375 mg/kg to females. All mice survived until the end of the study. Final mean body weights of 4,000 and 8,000 ppm females and mean body weight gains of 2,000, 4,000, and 8,000 ppm females were significantly greater than those of the controls. Feed consumption by exposed groups was similar to that by the controls, except that by the 8,000 ppm males, which was approximately 40&percnt; the amount of feed consumed by the control group. Histopathologic examinations were not performed due to the absence of mortality and significant exposure-related lesions. 16-DAY GAVAGE STUDY IN MICE: Groups of five male and five female B6C3F1 mice were given 0, 12.5 (twice daily), 25 (once daily), 50 (once daily), 50 (twice daily), 100 (once daily), 200 (once daily), 200 (twice daily), or 400 (once daily) mg theophylline/kg body weight in corn oil by gavage. Three males and all females receiving 400 mg/kg once daily died on day 1. There were no significant differences in final mean body weights or body weight gains. There were no histopathologic findings attributed directly to theophylline. 14-WEEK FEED STUDY IN RATS: Groups of 10 male and 10 female F344/N rats were given 0, 1,000, 2,000, or 4,000 ppm theophylline in feed for 14 weeks, which resulted in approximate daily doses of 75, 125, or 250 mg theophylline/kg body weight to males and 75, 125, or 275 mg/kg to females. The final mean body weight of 1,000 ppm females was significantly greater than that of the control group. Feed consumption by exposed groups was similar to that by the controls. Mean cell volume and mean cell hemoglobin were significantly greater in males exposed to 2,000 or 4,000 ppm than those in the control group. Segmented neutrophil counts of all groups of exposed females were significantly greater than that of the control group. The absolute and relative kidney weights of 4,000 ppm males were significantly greater than those of the controls, and there was an exposure-related increase in the severity of nephropathy in males. Exposure-related increases in the incidences of mesenteric and/or pancreatic periarteritis were observed in males and females. 14-WEEK GAVAGE STUDY IN RATS: Groups of 10 male and 10 female F344/N rats were given 0, 37.5, 75, or 150 mg theophylline/kg body weight in corn oil by gavage for 14 weeks. One male and one female receiving 150 mg/kg died before the end of the study. The mean body weight gain of 150 mg/kg females was significantly greater than that of the controls. Mean cell volume of 150 mg/kg males and mean cell hemoglobin of all groups of dosed males were significantly greater than those of the control group. There were slight dose-dependent increases in the incidences of mesenteric periarteritis in dosed males and females. 14-WEEK FEED STUDY IN MICE: Groups of 10 male and 10 female B6C3F1 mice were given 0, 1,000, 2,000, or 4,000 ppm theophylline in feed for 14 weeks, resulting in approximate daily doses of 175, 400, or 800 mg theophylline/kg body weight to males and 225, 425, or 850 mg/kg to females. All mice survived until the end of the study. The final mean body weights and body weight gains of all exposed groups of males and females were significantly less than those of the controls. Feed consumption by exposed groups was similar to that by the controls. Leukocyte, segmented neutrophil, and lymphocyte counts of 4,000 ppm males were significantly greater than those of the controls. Leukocyte and segmented neutrophil counts of 2,000 or 4,000 ppm females were significantly greater than those of the controls. There were no histopathologic findings attributed directly to theophylline exposure. 14-WEEK GAVAGE STUDY IN MICE: Groups of 10 male and 10 female B6C3F1 mice were given 0, 75, 150, or 300 mg theophylline/kg body weight in corn oil by gavage for 14 weeks. Three males and all females receiving 300 mg/kg, one 75 mg/kg male, and one control female died before the end of the study. Final mean body weights and body weight gains of 150 and 300 mg/kg males were significantly less than those of the controls. Mean cell volume and mean cell hemoglobin of 300 mg/kg males were significantly greater than those of the controls. There were no histopathologic findings attributed directly to theophylline treatment. 2-YEAR GAVAGE STUDY IN RATS: Groups of 50 male and 50 female rats were given 7.5, 25, or 75 mg theophylline/kg body weight in corn oil by gavage for 2 years. Survival and Body Weights: There were no significant differences in survival between dosed and control groups. Final mean body weights of all groups of dosed males and females were significantly less than those of the controls. Pathology Findings: There were no significantly increased incidences of neoplasms in dosed rats. The incidence of chronic inflammation of the mesenteric arteries was significantly increased in males receiving 75 mg/kg compared to the controls. There were doserelated negative trends in the incidences of mammary gland fibroadenoma and fibroadenoma or carcinoma (combined) in females; these differences correlated with decreased body weights. 2-YEAR GAVAGE STUDY IN MICE: Groups of 50 male B6C3F1 mice were given 0, 15, 50, or 150 mg theophylline/kg body weight and groups of 50 female B6C3F1 mice were given 0, 7.5, 25, or 75 mg/kg in corn oil by gavage for 2 years. Survival and Body Weights: Survival of 150 mg/kg males was significantly less than that of the controls. The final mean body weights of 150 mg/kg males, 25 mg/kg females, and 75 mg/kg females were significantly less than those of the control groups. Pathology Findings: There were no treatment-related increases in incidences of nonneoplastic lesions or neoplasms. In males and females, there were decreased incidences of hepatocellular adenoma and of the combined incidences of hepatocellular adenoma or carcinoma compared to the controls. Male mice had a pattern of nonneoplastic liver lesions along with silver-staining helical organisms in the liver consistent with Helicobacter hepaticus infection. The incidences of these liver lesions in 150 mg/kg males were significantly lower than those in control males. Increases in the incidences of hepatocellular neoplasms in male mice have been shown to be associated with H. hepaticus infection when hepatitis is also present. Because of this association, interpretation of the decreased incidence of liver neoplasms in male mice was more difficult. Incidences of lesions at other sites in this study were not considered to have been significantly impacted by H. hepaticus infection or its associated hepatitis. GENETIC TOXICOLOGY: Theophylline was not mutagenic in Salmonella typhimurium, with or without metabolic activation (S9). It induced sister chromatid exchanges but not chromosomal aberrations in cultured Chinese hamster ovary cells. The positive sister chromatid exchange response was noted only in the absence of S9. In vivo, a mouse bone marrow sister chromatid exchange test showed positive results at a standard 23-hour harvest time; however, this test was not repeated and the response is unconfirmed. An in vivo mouse bone marrow chromosomal aberrations test, that employed both standard and extended exposure protocols, gave negative results. The frequency of micronucleated erythrocytes was determined in peripheral blood of male and female mice exposed to theophylline in dosed feed or in corn oil by gavage for 14 weeks. No significant increases in the frequencies of micronucleated cells were seen in male or female mice in either of the studies. CONCLUSIONS: Under the conditions of these 2-year gavage studies, there was no evidence of carcinogenic activity of theophylline in male or female F344/N rats administered 7.5, 25, or 75 mg/kg. There was no evidence of carcinogenic activity of theophylline in male B6C3F1 mice administered 15, 50, or 150 mg/kg or female B6C3F1 mice administered 7.5, 25, or 75 mg/kg. Gavage administration of theophylline caused chronic inflammation of the mesenteric arteries in dosed male rats. Decreased incidences of mammary neoplasms in female rats were likely associated with lower body weights. There were dose-related decreases in the incidences of hepatocellular adenoma and hepatocellular carcinoma in male and female mice. Synonyms: 3,7-dihydro-1,3-dimethyl-1H-purine-2,6-dione; 1,3-dimethylxanthine; 1H-purine-2,6-dione; NSC 2066; pseusdotheophylline; theocin; theophyllin; theophylline, anhydrous Trade names: Accurbron; Aerobin; Aerolate III; Afonilum; Aminophylline; Aquaphyllin; Armophylline; Asmalix; Bilordyl; Bronchoretard; Bronkodyl; Cetraphylline; Constant-T; Diffumal; Duraphyl; Duraphyllin; Elixicon; Elixophyllin; Euphylline L.A.; Euphylong; LaBID; Labophylline; Lanophyllin; Lasma; Liquophylline; Optiphyllin; Parkophyllin; Phylocontin; Physpan; Pro-Vent; PulmiDur; Pulmo-Timelets; Quibron; Respbid; Rona-Phyllin; Sabidal; Slo-bid; Slo-Phyllin; Solosin; Sustaire; Tefamin; Teobid; Teofyllamin; Tesona; Theal tablets; Theo-24; Theobid; Theocap; Theochron; Theoclear; Theocontin; Theo-Dur; Theofol; Theograd; Theolair; Theolan; Theolix; Theophyl; Theoplus; Theo-Sav; Theosol; Theospan; Theostat; Theovent; TheoX; T-Phyl; Truphylline; Uni-Dur; Unifyl; Uniphyl; Uniphyllin; Xanthium
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PMID:NTP Toxicology and Carcinogenesis Studies of Theophylline (CAS No. 58-55-9) in F344/N Rats and B6C3F1 Mice (Feed and Gavage Studies). 1257 77

Trichloroethylene (TCE) is an industrial solvent used for vapor degreasing and cold cleaning of fabricated metal parts. TCE has also been used as a carrier solvent for the active ingredients of insecticides and fungicides, as a solvent for waxes, fats, resins, and oils, as an anesthetic for medical and dental use, and as an extractant for spice oleoresins and for caffeine from coffee. Trichloroethylene may be found in printing inks, varnishes, adhesives, paints, lacquers, spot removers, rug cleaners, disinfectants, and cosmetic cleansing fluids. TCE may also be used as a chain terminator in polyvinyl chloride production and as an intermediate in the production of pentachloroethane. Trichloroethylene is no longer used with food, drugs, or cosmetics. NTP Carcinogenesis studies of epichlorohydrin-free trichloroethylene were conducted by administering the test chemical in corn oil by gavage to groups of 50 male and 50 female F344/N rats and B6C3F1 mice. Dosage levels were 500 and 1,000 mg/kg for rats and 1,000 mg/kg for mice. Trichloroethylene was administered five times per week for 103 weeks, and surviving animals were killed between weeks 103 and 107. Groups of 50 rats and 50 mice of each sex received corn oil by gavage on the same schedule and served as vehicle controls. Groups of 50 male and 50 female rats were used as untreated controls. The dosage levels selected for the 2-year study were based on the results of the 13-week studies. Groups of 10 male and 10 female rats received TCE by gavage at doses of 125 to 2,000 mg/kg (males) and 62.5 to 1,000 mg/kg (females) for 13 weeks. Groups of 10 male and 10 female mice received gavage doses of 375 to 6,000 mg/kg of TCE for 13 weeks. Survival, body weight gains, and previous experience with TCE were used to select doses for the 2-year study. All rats survived the 13-week study, but males receiving 2,000 mg/kg exhibited a 24% difference in final body weight. At the 1,000 mg/kg dose, final body weights for males (-3%) and for females (-2%) were similar to those of controls. The doses selected for the 2-year study in rats were 500 and 1,000 mg/kg for both sexes. The initial doses used in the earlier bioassay in Osborne-Mendel rats were 549 and 1,097 mg/kg for both sexes. A total of 8/10 male mice and 10/10 female mice receiving doses of TCE as high as 1,500 mg/kg survived the 13-week experimental period. The single dosage level selected for the 2-year study in mice was 1,000 mg/kg for both sexes. This dose was less than the high dose used in the earlier bioassay in B6C3F1 mice (2,339 mg/kg for males and 1,739 for females) and was similar to the previous low doses (1,169 mg/kg for males and 869 for females). In the 2-year study, the survival of both low and high dose male rats and dosed male mice was less (P</=0.005) than that of the vehicle controls. Mean body weights of dosed rats of each sex were lower than those of the vehicle controls, and after week 65, the decrements in body weight gains were dose related. The mean body weight of dosed male mice was lower than that of the vehicle controls throughout the study, while those of the dosed and vehicle control female mice were comparable. Cytomegaly (toxic nephrosis) of the kidney was observed in 96/98 male and in 97/97 female rats given TCE, with none being found in male or female vehicle control rats. This lesion was more severe in males, particularly in the high dose group. Cytomegaly was observed in 45/50 male mice and in 48/49 female mice administered TCE, and in none of the vehicle controls. Renal tubular cell adenocarcinomas were found in the three high dose male rats; these neoplasms were observed in those male rats killed at the end of the study (0/33, 0/20, and 3/16, 19%). The incidence in the high dose male rats at the end of the study was greater (P<0.05) than that in the controls. Renal tubular cell adenocarcinomas are considered uncommon occurrences in F344/N rats, with 3/748 (0.4%) being observed in historical vehicle gavage controls. Additional renal tumors in dosed male rats included one transitional cell carcats included one transitional cell carcinoma of the renal pelvis and two tubular cell adenomas in low dose animals and one carcinoma of the renal pelvis in a high dose animal. No renal neoplasms were found in vehicle control rats; one untreated control male rat had a transitional cell papilloma of the renal pelvis. In female rats, one tubular cell adenocarcinoma was found in the high dose group. An increased incidence (P&lt;0.05, life table) of peritoneal mesotheliomas was detected in low dose male rats (control, 1/50; low dose, 5/50; high dose, 1/49). Mesotheliomas have been diagnosed in 16/752 (2.1&percnt;) historical vehicle control male F344/N rats, and the increased incidence in the present study may have been related to the administration of TCE. The results in male F344/N rats were considered equivocal for detecting a carcinogenic response because both groups receiving TCE showed significantly reduced survival compared to vehicle controls (35/50, 70&percnt;, 20/50, 40&percnt;; 16/50, 32&percnt;) and because 20&percnt; of the animals in the high dose group were killed accidently by gavage error. Negative trends were observed for chromophobe adenomas of the pituitary gland and for endometrial stomal polyps in female rats. These decreases were not considered to be related to the administration of TCE. The administration of TCE to mice caused increased incidences of hepatocellular carcinoma in males (control, 8/48; dosed, 31/50; P&lt;0.001) and in females (control, 2/48; dosed, 13/49; P&lt;0.005). Hepatocellular carcinomas metastasized to the lungs in five dosed male mice and one control male mouse, and none were observed in females. The incidence of hepatocellular adenomas was increased in male mice (control, 7/48; dosed 14/50) and in female mice (control, 4/48; dosed, 16/49; P&lt;0.05). Under the conditions of these studies, epichlorohydrin-free trichloroethylene caused renal tubular-cell neoplasms in male F344/N rats, produced toxic nephrosis in both sexes, and shortened the survival time of males. This experiment in male F344/N rats was considered to be inadequate to evaluate the presence or absence of a carcinogenic response to trichloroethylene. For female F344/N rats receiving trichloroethylene, containing no epichlorohydrin, there was no evidence of carcinogenicity. Trichloroethylene (without epichlorohydrin) was carcinogenic for B6C3F1 mice, causing increased incidences of hepatocellular carcinomas in males and females and of hepatocellular adenomas in females. Levels of Evidence of Carcinogenicity: Male Rats: Inadequate Study Female Rats: Negative Male Mice: Positive Female Mice: Positive Synonym: TCE
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PMID:NTP Carcinogenesis Studies of Trichloroethylene (Without Epichlorohydrin) (CAS No. 79-01-6) in F344/N Rats and B6C3F1 Mice (Gavage Studies). 1275 Jul 50

In locally advanced pancreatic cancer, the utilization of chemotherapy and radiotherapy is increasing, although in view of the reported long-term results of several contemporary trials, further improvements are certainly needed. Encouraging results using the combination of cisplatin, cytarabine, caffeine, and continuous infusion (CI) 5-fluorouracil (5-FU) (PACE) for the treatment of advanced pancreatic carcinoma prompted a phase II study using PACE followed by external beam radiotherapy with CI of 5-FU (PACE-RT) for localized disease. Forty-one patients were treated with PACE-RT as adjuvant therapy after surgical resection (21 patients), or as primary therapy for locally advanced, unresectable disease (20 patients), with reevaluation for resection after completion of treatment. PACE consisted of cisplatin 100 mg/m2 IV on day 1, cytarabine 2 g/m2 IV every 12 hours x 2 doses, and caffeine 400 mg/m2 subcutaneously after each cytarabine dose; and days 3 to 21, 5-FU 250 mg/m2/d given by CI. Cycles were repeated every 28 days. After 2 cycles of PACE, radiation therapy was given concurrently with 5-FU at 200 mg/m2/d. In the adjuvant setting, the tumor bed and the draining lymph node basin received 50.4 Gy and 45 Gy, respectively. In the neoadjuvant setting, the primary and regional lymph nodes were to receive 39.6 Gy followed by a neutron boost of 8 NGy to the gross tumor volume. Photon therapy was delivered at 1.8 Gy per fraction and neutron therapy at 0.8 NGy per fraction, 5 days a week. All patients were evaluable for toxicity and survival. The most common toxicity was myelosuppression, with grade III to IV neutropenia occurring in 59% of the patients. The median survival times in the locally advanced and adjuvant patients were 13.4 and 18.1 months, with 1-year survival rates of 52% and 65%, respectively. Nine of 20 patients receiving PACE-RT for unresectable carcinoma had sufficient tumor regression to meet clinical criteria for exploration; three were resected with curative intent. The survival of these three patients undergoing resection after neo-adjuvant therapy was 22.4, 24.3 and 40 months. The treatment program was active, but only moderately well tolerated. Modification of this regimen with newer, less toxic drugs may provide better results and reduced toxicity.
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PMID:Chemoradiotherapy in the treatment of regional pancreatic carcinoma: a phase II study. 1466 69

Caffeine has been widely described as a chemo/radiosensitizing agent, presumably by inhibiting DNA repair, and affecting preferentially cells with an altered p53 status. We evaluated the effects of caffeine using isogenic and isophenotypic K1 cells derived from a papillary thyroid carcinoma and displaying either a wild type or a mutated p53 status. Apoptosis and clonogenic survival were examined after exposure of the cells to cisplatin or UVc irradiation. We find that at the most currently used concentration, 2mM, caffeine hinders cisplatin or UVc induced apoptosis in K1 cells. In addition, at this already barely achievable concentration in vivo, caffeine does not decrease their clonogenic survival. Hence in our cellular model, caffeine does not behave as a chemo- or a radiosensitizer. Although surprising, these results (1) are in agreement with the delayed G2/M block caused by caffeine that we previously observed in normal human fibroblasts and K1 cells and (2) allow us to elucidate some discrepancies concerning this molecule throughout the literature such as increase or decrease of apoptosis and clonogenic survival, activation or deactivation of molecules involved in DNA damage repair and proliferation inhibition but accelerated G2/M traverse.
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PMID:Conflicting effects of caffeine on apoptosis and clonogenic survival of human K1 thyroid carcinoma cell lines with different p53 status after exposure to cisplatin or UVc irradiation. 1475 Dec 46

We previously reported a method of preparing finely powdered green tea (PT), powder characteristics and release profiles of green tea components from PT. In this study, we performed formulation studies of PT tablets containing mitomycin C (MMC), expecting its combined antitumor effects with mitomycin C and green tea components. The hardness of PT tablets was low (22-50 N) and the disintegration time was about 180 min regardless of hardness or tabletting pressure (15-200 MPa). Perfiller-101 improved tablet characteristics practically into 90 N of hardness and 18.5 min of disintegration time. Release rates of MMC, caffeine and EGCG from the tablets were similar, and depended on the disintegration time. PT and epigallocatechin gallate (EGCG) increased significantly in MMC uptake in Ehrlich ascites carcinoma cells as compared with the control dose-dependently in vitro.
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PMID:A dosage design of mitomycin C tablets containing finely powdered green tea. 1508 Nov 58

Chronic ingestion (for 22-30 consecutive days) of caffeine (20 mg/kg/day, p.o.) increased the activities of the hepatic enzymes- catalase (CAT) and superoxide dismutase (SOD) and decreased its lipid peroxidation (LP) in mice. Development of Ehrlich ascites carcinoma (EAC) cell decreased the activities of hepatic CAT and SOD and increased LP. But pretreatment of caffeine for 12 consecutive days and continuation of its treatment during the course of development of EAC cells restored the EAC cell-induced changes in liver CAT, SOD and LP to their corresponding control values. Thus, the present results by confirming the results of others previously published, suggest that caffeine is an antioxidant and may act as an anticarcinogen.
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PMID:Chronic administration of caffeine: effect on the activities of hepatic antioxidant enzymes of Ehrlich ascites tumor-bearing mice. 1525 35


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