Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0699790 (colon cancer)
28,837 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. n-Butyrate, a short chain fatty acid produced by colonic fermentation, induces differentiation in human neoplastic cell lines, and reduces expression in vitro of a sialyltransferase that glycosylates N-linked glycoproteins in hepatoblastoma cells. Gangliosides are amphipathic, sialylated glycosphingolipids that undergo profound changes in many transformed cells and may protect neoplastic cells from host immune surveillance. Colonic mucosal cells are exposed to luminal short-chain fatty acid concentrations of up to 80 mmol/l, and there is some evidence that short-chain fatty acids may alter ganglioside expression in colon cancer cells. 2. Because of the importance of gangliosides in cancer pathogenesis, we investigated the effects of n-butyrate on ganglioside expression of colonic (human and murine) and non-colonic cancer cells. 3. Three separate colon cancer cell lines (LS174T, T84 and MCA-38), when butyrate treated, demonstrated striking amplification of specific individual gangliosides. However, the total lipid-bound sialic acid content of gangliosides of butyrate-treated LS174T cells diminished. In contrast to earlier reports, n-butyrate did not mediate expression of all gangliosides and specifically did not mediate expression of GM3. This effect persisted even after removal of butyrate. 4. In contrast, exposure of extracolonic cells to butyrate, including cervical cancer (HeLa) and laryngeal cancer (HEp-2) cell lines in this study and hepatoblastoma cells (Hep G2) in our previous work, caused no detectable changes in ganglioside expression. 5. In conclusion, our results indicate a relative tissue specificity of butyrate-mediated alterations in ganglioside expression that is not universal but is limited to specific gangliosides.
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PMID:n-Butyrate mediation of ganglioside expression of human and murine cancer cells demonstrates relative cell specificity. 778 51

Depletion of mevalonic acid (MVA), obtained by inhibition of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase using lovastatin, depressed the biosynthesis of dolichyl-phosphate and the rate of N-linked glycosylation and caused growth arrest in the melanoma cell line SK-MEL-2. The growth arrest was partially prevented by addition of high concentrations of insulin-like growth factor-1 (IGF-1) to the cells, indicating that MVA depletion may inhibit cell growth through decreasing the number of IGF-1 receptors (IGF-1R) at the cell surface. Such a decrease in receptor number might be a result of a lowered translocation of de novo synthesized receptors to the cell membrane which in turn might be a result of a decreased N-linked glycosylation of the receptor proteins. We could also demonstrate that IGF-1R became underglycosylated and that the amount of de novo synthesized IGF-1R proteins at the cell membrane was drastically decreased upon MVA depletion. Analysis of receptor proteins cross-linked with IGF-1, as well as binding assays and immunocytostaining confirmed that the number of functional membrane-bound IGF-1R was substantially reduced. The N-linked glycosylation and the expression of de novo synthesized IGF-1R proteins at the cell surface as well as the number of IGF-1 binding sites were completely restored upon replenishment of MVA. These effects of MVA were efficiently abrogated by the glycosylation inhibitor tunicamycin. The translocation of IGF-1R to the cell membrane was shown to take place just prior to initiation of DNA synthesis in arrested cells stimulated with MVA. Additionally, there was a clear correlation between IGF-1 binding and initiation of DNA synthesis with regard to the MVA dose requirement. It was confirmed that inhibition of HMG-CoA reductase activity and N-linked glycosylation also depressed the expression of functional IGF-1R in other cell types (i.e. hepatoblastoma cells and colon cancer cells). Our data suggest that this mechanism is involved in MVA-regulated cell growth.
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PMID:Mevalonic acid is limiting for N-linked glycosylation and translocation of the insulin-like growth factor-1 receptor to the cell surface. Evidence for a new link between 3-hydroxy-3-methylglutaryl-coenzyme a reductase and cell growth. 866 39

We used a yeast functional assay (functional analysis of separated alleles in yeast: FASAY) to determine the p53 gene status of human cell lines maintained in our laboratory. This assay enables the researcher to score wild-type p53 expression on the basis of the ability of expressed p53 to transactivate the reporter gene HIS 3 via the p53-responsive GAL 1 promoter in Saccharomyces cerevisiae. The cell lines examined were ten hepatoma, two hepatoblastoma, three in vitro immortalized fibroblast, two osteosarcoma, a chondrosarcoma, an ovarian teratocarcinoma and a colon cancer cell line. Out of 20 cell lines, 11 cell lines had mutations in both alleles of the p53 gene, and another 8 cell lines had no mutation in the p53 gene. Thus, 55% of the cell lines examined had mutations in the p53. Interestingly, PA-1 cells had both the normal and the mutant p53 alleles, showing that FASAY is a useful method for detecting the wild-type and mutated p53 genes simultaneously. As for the three liver cell lines harboring HBsAg, there was no relationship between their p53 gene status and the presence of HBsAg. Two cell lines were normal for p53 status, while the other had a mutation of the p53 gene.
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PMID:Yeast functional assay of the p53 gene status in human cell lines maintained in our laboratory. 935 23

Rice is a staple diet in Asia, where the incidence of breast and colon cancer is markedly below that in the Western world. We investigated potential colon and breast tumor-suppressive properties of rice, testing the hypothesis that rice contains phenols that interfere with the proliferation or colony-forming ability of breast or colon cells. Brown rice, its white milled counterpart, and bran from brown rice were boiled and extracted with ethyl acetate. The extracts were analyzed by high pressure liquid chromatography-mass spectrometry. Eight phenols, protocatechuic acid, p-coumaric acid, caffeic acid, ferulic acid, sinapic acid, vanillic acid, methoxycinnamic acid, and tricin, were identified in the extracts of bran and intact brown rice. These extracts were separated into nine fractions by column chromatography. The effect of bran extract and its fractions at 100 microg/ml on cell viability and colony-forming ability of human-derived breast and colon cell lines was assessed. Bran extract decreased numbers of viable MDA MB 468 and HBL 100 breast cells and colon-derived SW 480 and human colonic epithelial cells as judged by the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4 -sulfophenyl)-2H-tetrazolium assay. It also reduced colony formation of SW 480 colon and MDA MB 468 breast cells. Of the eight phenols identified in the brown rice bran, when applied at 50 microM, caffeic acid decreased numbers of all cell types except HBL 100. Tricin, ferulic acid, and methoxycinnamic acid interfered with cell viability in one or more cell lines. Tricin (50 microM) and the other phenols (200 microM) inhibited colony formation of SW 480 cells. Clonogenicity of MDA MB 468 cells was inhibited by caffeic acid, ferulic acid, and tricin (50 microM). Tricin was the most potent anticlonogenic of the compounds with IC50s of 16 microM in the SW 480 colon cells and 0.6 microM in the MDA MB 468 breast cells. The results suggest that: (a) brown rice and bran contain compounds with putative cancer chemopreventive properties; (b) certain phenols contained in brown rice bran, e.g., tricin, may be associated with this activity; and (c) these phenols are present at much lower levels in white than in brown rice. Thus, the consumption of rice bran or brown rice instead of milled white rice may be advantageous with respect to cancer prevention.
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PMID:Characterization of potentially chemopreventive phenols in extracts of brown rice that inhibit the growth of human breast and colon cancer cells. 1109 23

We have reported that glutathione-doxorubicin conjugate (GSH-DXR) exhibited potent cytotoxicity against tumor cells and inhibited glutathione-S-transferase (GST) enzyme activity. In order to determine whether or not the expression of GST-pi lowered the cytotoxicity of GSH-DXR, cytocidal activity of the conjugate was examined using tumor cells in which the level of GST-pi expression was regulated by transfecting GST-pi cDNA in the correct or reverse direction and comparing with that of DXR. Enhancement of GST-pi expression by transfecting GST-pi sense cDNA into human hepatoblastoma HepG2 cells in which GST-pi expression was extremely low caused an increase in GST activity from 0.26 to 55.0 nmol/mg/min and a marked reduction in transfectant sensitivity to GSH-DXR to 1/120 (0.15-18 nM IC50) although the sensitivity to DXR was slightly decreased to 1/2.6 (380-990 nM IC50). By contrast, a high GST-pi-expressing human colon cancer cell line, HT29, showed a decrease in GST enzyme activity from 72.0 to 45.9 nmol/mg/min after transfecting GST-pi antisense cDNA and a marked improvement in transfectant sensitivity to GSH-DXR was observed (28-2.9 nM IC50) compared with the transfectant sensitivity to DXR (1020-320 nM IC50). Additionally, the expression of GST-pi in HepG2 cells caused a decrease in GSH-DXR-induced activation of caspase-3, which was an apoptotic marker, whereas the suppression of GST-pi in HT29 cells showed an increase in caspase-3 activation. These results suggested that the cytocidal efficacy of GSH-DXR, but not that of DXR, was controlled by the level of GST-pi expression in the cells.
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PMID:Glutathione-S-transferase-pi expression regulates sensitivity to glutathione-doxorubicin conjugate. 1160 59

1-Amino-2,4-dibromoanthraquinone is an anthraquinone-derived vat dye, a member of a class of insoluble dyes that are impregnated into textile fibers. Five anthraquinone-derived dyes with representative and diverse structures, as well as the parent chemical, anthraquinone, were selected for NTP Toxicology and Carcinogenesis evaluation. Similar to the benzidine dye initiative, the rationale for selecting these vat dyes was to generate sufficient toxicologic data to permit more reliable predictions of carcinogenicity to be made on other chemicals in this class, thereby eliminating or reducing the need to study every anthraquinone dye. 1-Amino-2,4-dibromoanthraquinone is the last anthraquinone-derived dye in this group to be studied. Groups of male and female F344/N rats and B6C3F1 mice were exposed to 1-amino-2,4-dibromoanthraquinone (87% to 97% pure) for 13 weeks or for 9, 15, or 24 months. Because 1-amino-2,4-dibromoanthraquinone was predicted to be carcinogenic, these studies were designed to evaluate the potential for tumor progression and regression. Absorption and excretion studies were carried out in male F344/N rats. Genetic toxicity was determined in vitro using Salmonella typhimurium and cultured Chinese hamster ovary cells. Extensive chemical analyses were performed to identify and characterize impurities of the 1-amino-2,4-dibromoanthraquinone used in these studies. 13-WEEK STUDY IN RATS: Groups of 10 male and 10 female rats were given 0, 2,500, 5,000, 10,000, 25,000, or 50,000 ppm 1-amino-2,4-dibromoanthraquinone in feed for 13 weeks. These levels correspond to approximately 150 to 3,200 mg 1-amino-2,4-dibromoanthraquinone/kg body weight per day for males and to approximately 170 to 3,200 mg/kg for females. Chemical-related mortality was limited to one male and one female in the 50,000 ppm groups. Final mean body weights and body weight gains of all exposed groups of rats were significantly lower than those of the controls. Feed consumption by all exposed groups was less than that by the controls throughout the study and generally decreased with increasing exposure concentration. Pink-red staining of the fur and tail was observed in all exposed groups. Absolute and relative liver weights of all exposed groups were generally significantly greater than those of the controls. Chemical-related lesions were present in the liver, kidney, and spleen of male and female rats. Nonneoplastic lesions in the liver included foci of hepatocellular alteration, diffuse hepatocellular hypertrophy (cytomegaly), hepatocellular cytoplasmic vacuolation, bile duct hyperplasia, inflammation, and pigmentation. These differences were observed primarily in the 25,000 and 50,000 ppm groups of males and females; the spectrum of proliferative lesions of the bile ducts (hyperplasia, fibrosis, and necrotizing cholangitis) in the 25,000 and 50,000 ppm groups was morphologically consistent with the lesion described as cholangiofibrosis. Pigmentation was present in the renal tubule epithelium of all groups of exposed rats; nuclear enlargement (karyomegaly) was also present in the renal tubule epithelium in some of the exposed rats. Accumulation of hyaline droplets in the cytoplasm of the renal tubule epithelium and tubule lumina was present in 2,500, 5,000, 10,000, and 25,000 ppm males. Incidences of hematopoiesis of the spleen in exposed groups of males and females were increased compared to those in the controls. 13-WEEK STUDY IN MICE: Groups of 10 male and 10 female mice were given 0, 2,500, 5,000, 10,000, 25,000, or 50,000 ppm 1-amino-2,4-dibromoanthraquinone in feed for 13 weeks. These levels correspond to approximately 500 to 10,600 mg 1-amino-2,4-dibromoanthraquinone/kg body weight per day for males and approximately 660 to 11,700 mg/kg per day for females. There was no chemical-related mortality. Feed consumption and final mean body weights of exposed groups were similar to those of the controls. Red staining of the fur was observed in all exposed groups. Absolute and relative liver weights of the exposed groups were greater than those er than those of the controls except for the absolute liver weight of 2,500 ppm males. Absolute and relative kidney weights of 25,000 and 50,000 ppm males were lower than those of the controls. Chemical-related lesions were limited to the livers of males and consisted of pigmentation of hepatocytes at all exposure concentrations and centrilobular hepatocellular hypertrophy at 10,000, 25,000, and 50,000 ppm. Minimal pigment was present in the liver of one female in the 25,000 ppm group and in one female in the 50,000 ppm group. 2-YEAR STUDY IN RATS: Groups of 70 male and 70 female rats were given 0, 5,000, or 10,000 ppm 1-amino-2,4-dibromoanthraquinone in feed for 103 weeks. In addition, groups of 50 male and 50 female rats were given 2,000 ppm 1-amino-2,4-dibromoanthraquinone in feed for 104 weeks. These exposure concentrations were approximately equal to 90, 240, or 490 mg 1-amino-2,4-dibromoanthraquinone/kg body weight for males and 110, 285, or 600 mg/kg for females. Ten animals from each group were evaluated for histopathology at 9 months. Additional groups of 10 animals from the 0 and 10,000 ppm groups were evaluated for histopathology at 15 months. Survival, Body Weights, Feed Consumption, and Clinical Findings In the 2-year study, survival of the 10,000 ppm males and females was significantly lower than that of the controls. Survival of the 2,000 and 5,000 ppm groups was similar to that of the controls. During the last year of the study, the mean body weights of exposed males were 80% to 91% those of controls, and the mean body weights of exposed females were 67% to 84% those of controls. Feed consumption among exposed groups was generally similar, but was less than that by controls. The fur and urine of all exposed male and female groups were discolored. Pathology Findings In the 2-year study, 1-amino-2,4-dibromoanthraquinone was associated with significant chemical-related increases in the incidences of benign and malignant neoplasms in the liver, large intestine, kidney, and urinary bladder of males and females. Chemical-related nonneoplastic proliferative and degenerative lesions occurred in the liver, kidney, urinary bladder, and forestomach of males and females. The incidences of foci of hepatocellular alteration and pigmentation in the liver of males and females were increased at the 9-month interim evaluation, and a hepatocellular adenoma was present in one 5,000 ppm male. At the 15-month interim evaluation, hepatocellular adenoma or carcinoma (combined) occurred in all males and nine females in the 10,000 ppm groups. By the end of the 2-year study, hepatocellular adenoma, carcinoma, cholangioma, or cholangiocarcinoma were observed in males and females in the 5,000 and 10,000 ppm groups. In the 2,000 ppm groups, similar liver neoplasms were present in 63% of the males and in 83% of the females. Of the hepatocellular carcinomas in the 5,000 and 10,000 ppm groups of males and females, 31% to 49% were metastatic to the lungs or other sites. Increases in the incidences of foci of hepatocellular alteration (basophilic, eosinophilic, and clear cell) and pigmentation of the liver were also observed in exposed groups of males and females. Adenomatous polyps (adenoma) of the large intestine were present in six 10,000 ppm males at the 15-month interim evaluation. Incidences of adenomatous polyp (adenoma) and carcinoma of the large intestine were significantly increased in exposed groups of males and females after 2 years; multiple benign and malignant intestinal neoplasms were observed in many of these rats. In the kidney, incidences of renal tubule adenoma and carcinoma were significantly increased in exposed groups of males and females after 2 years. Renal tubule adenomas were present in two 10,000 ppm males at 15 months. There were also chemical-related increases in the incidences and severities of renal tubule epithelial hyperplasia, pigmentation, and transitional cell hyperplasia in the kidney of males and females. Hyaline droplet accumulation was present in all exposed male rats at 9 months. Incidences of transitional cell papilloma and carcinoma of the urinary bladder were increased at 2 years in males and females in the 10,000 ppm groups. Transitional cell hyperplasia was observed in exposed males and females at the 15-month interim evaluation. Other nonneoplastic lesions observed in the urinary bladder at 2 years included metaplasia of the transitional epithelium and submucosal stromal tissue. In the forestomach, the incidences and severities of inflammation, ulceration, hyperkeratosis, and hyperplasia of the squamous mucosa were increased in all exposed groups of males and females at 2 years, but not at the 9- or 15-month interim evaluations. In exposed males and females, the incidences of mononuclear cell leukemia were significantly decreased. The incidences of atrophy of the seminal vesicle were increased in exposed male rats in the 2-year study. Stop-Exposure Evaluation in Rats Groups of 40 male and 40 female rats were given 20,000 ppm 1-amino-2,4-dibromoanthraquinone in feed for 9 or 15 months. At 9 months, 10 males and 10 females were evaluated for histopathology (9-month interim evaluation groups). After 9 months of exposure, an additional 10 males and 10 females were fed control diet until the end of the 15-month evaluation (9-month stop-exposure groups), and 20 males and 20 females continued to receive 20,000 ppm 1-amino-2,4-dibromoanthraquinone until the end of the evaluation (15-month exposure groups). The approximate daily consumption of 1-amino-2,4-dibromoanthraquinone was 1,335 mg/kg for males and 1,790 mg/kg for females in the 9-month stop-exposure groups and 1,115 mg/kg for males and 1,435 mg/kg for females in the 15-month exposure groups. Survival was similar among groups except for the females in the 15-month exposure group; the survival of this group was lower than that of the controls. Lower mean body weights were related to increased exposure duration. The mean body weights of exposed males were 76% to 82% that of controls, and the mean body weights of exposed females were 73% to 84% that of controls. For the stop-exposure evaluation, similar chemical-related neoplasms and nonneoplastic lesions were observed in the same sites as in the 2-year study: liver, large intestine, kidney, urinary bladder, and forestomach. After 9 months of dietary exposure to a concentration of 20,000 ppm 1-amino-2,4-dibromoanthraquinone, hepatocellular adenoma and carcinoma occurred in males and females. Nonneoplastic chemical-related lesions in the liver of exposed rats included pigmentation, focal hepatocellular alteration, and bile duct hyperplasia. Neoplasms at other sites in males included one adenomatous polyp (adenoma) in the large intestine and one transitional cell papilloma in the urinary bladder. Hyaline droplet accumulation was present in the kidney of exposed males at 9 months. In the stop-exposure groups examined at 15 months, hepatocellular adenoma and carcinoma were present in most males and females. Adenomatous polyp (adenoma) of the colon, renal tubule cell adenoma, and urinary bladder transitional cell papilloma and carcinoma also occurred in males and females. Nonneoplastic chemical-related lesions included foci of hepatocellular alteration in the liver and hyperplasia of the renal tubule epithelium and urinary bladder transitional epithelium. Hyperplasia, hyperkeratosis, inflammation, and ulceration were observed in the forestomach of some male and female rats continuously exposed for 15 months. 2-YEAR STUDY IN MICE: Groups of 60 male and 60 female mice were given 0, 10,000, or 20,000 ppm 1-amino-2,4-dibromoanthraquinone in feed for 104 weeks. The daily compound consumption was approximately 1,690 or 3,470 mg 1-amino-2,4-dibromoanthraquinone/kg body weight for males and 1,950 or 4,350 mg/kg for females. Ten animals from each group were evaluated for histopathology at 15 months. Survival, Body Weights, Feed Consumption, and Clinical Findings In the 2-year study, survival of exposed males was significantly lower than that of the controls. Survival of exposed females was similar to that of the controls. The final mean body weights of exposed males were 83% to 85% that of controls, and the final mean body weights of exposed females were 81% to 86% that of controls. Feed consumption by exposed groups was generally similar to that by controls. Discoloration of the fur, urine, and feces was observed in all exposed groups. Pathology Findings In the 2-year study, 1-amino-2,4-dibromoanthraquinone was associated with significant chemical-related increases in the incidences of benign and malignant neoplasms in the liver, forestomach, and lung of males and females. Incidences of hepatocellular adenoma and carcinoma were increased in exposed groups at the 15-month interim evaluation and at 2 years. At 2 years, there were significant increases in the incidences of multiple hepatocellular adenoma and carcinoma in males and females and in the incidences of hepatoblastoma in males. Centrilobular hypertrophy of hepatocytes in males and foci of hepatocellular alteration and pigmentation in the liver of males and females were also chemical-related changes. Sqamous cell papilloma of the forestomach mucosa occurred in 10,000 ppm females and 20,000 ppm males and females at the 15-month interim evaluation, and the incidences of squamous cell papilloma and carcinoma were significantly increased in exposed groups of males and females at 2 years. Chemical-related hyperplasia of forestomach epithelium was also present at 15 months and at 2 years. Alveolar/bronchiolar adenomas were present only in the exposed groups of males and females at 15 months, and the incidences of alveolar/bronchiolar adenoma were significantly increased in exposed males and females at 2 years. The incidences of multiple alveolar/bronchiolar adenomas were also increased in exposed males. In the kidney, pigmentation was present in the renal tubules of most mice after 2 years of exposure. DISPOSITION AND METABOLISM STUDIES: Adult male F344/N rats were given [14C]-labeled 1-amino-2,4-dibromoanthraquinone as a single intravenous dose of 0.4 mg/kg body weight or as a single oral dose of 2, 23, 118, 814, or 1,473 mg/kg. A 6-hour bile cannulation study was also performed. From day 0 through day 3 after intravenous administration, about 50% of the 14C was excreted in the feces, 15% in the urine, and 6% in expired air. Unmetabolized 1-amino-2,4-dibromoanthraquinone accounted for less than 3% of the excreted 14C after intravenous administration. For oral doses administered, the amount of the dose that was absorbed fit the equation: absorbed dose = 6.6 x log(dose). After intravenous administration, the metabolites of 1-amino-2,4-dibromoanthraquinone in blood were primarily in the plasma fraction (blood:plasma ratio of approximately 0.5:1). The highest concentrations of 14C in tissues 15 minutes after intravenous dosing were in excretory organs, lung, kidney, small intestine, liver, adipose tissue, and adrenal gland. GENETIC TOXICOLOGY: 1-Amino-2,4-dibromoanthraquinone was mutagenic in Salmonella typhimurium strains TA98 and TA1537 in the absence of S9; with S9, an equivocal response was observed in TA1537. 1-Amino-2,4-dibromoanthraquinone resulted in an equivocal response in TA100 with and without S9, and no mutagenic activity was detected with strain TA1535. In cultured Chinese hamster ovary cells, 1-amino-2,4-dibromoanthraquinone induced sister chromatid exchanges with and without S9; chromosomal aberrations were induced in the absence of S9. CONCLUSIONS: Under the conditions of these 2-year feed studies, there was clear evidence of carcinogenic activity of 1-amino-2,4-dibromoanthraquinone in male and female F344/N rats based on increased incidences of neoplasms in the liver, large intestine, kidney, and urinary bladder. There was clear evidence of carcinogenic activity of 1-amino-2,4-dibromoanthraquinone in male and female B6C3F1 mice based on increased incidences of neoplasms in the liver, forestomach, and lung. Exposure of male and female rats to 1-amino-2,4-dibromoanthraquinone for 2 years was associated with basophilic focus (males only), clear cell focus, eosinophilic focus, and pigmentation in the liver; renal tubule hyperplasia, renal tubule pigmentation, and transitional cell hyperplasia in the kidney; transitional cell hyperplasia, squamous metaplasia, and stromal metaplasia (females only) in the urinary bladder; squamous hyperplasia, hyperkeratosis, ulceration, and inflammation of the forestomach mucosa; and seminal vesicle atrophy. Exposure of male and female mice to 1-amino-2,4-dibromoanthraquinone for 2 years was associated with centrilobular hepatocellular hypertrophy (males only), basophilic focus, clear cell focus (females only), eosinophilic focus, and pigmentation in the liver; pigmentation in the kidney; and hyperplasia, basal cell hyperplasia, hyperkeratosis, and inflammation of the forestomach mucosa. Synonym: ADBAQ
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PMID:NTP Toxicology and Carcinogenesis Studies of 1-Amino-2,4-Dibromoanthraquinone (CAS No. 81-49-2) in F344/N Rats and B6C3F1 Mice (Feed Studies). 1269 53

The in vitro cytotoxic activity profile of nine novel phenylarsonic acid (CAS 98-05-5, PAA) compounds against 17 human cancer cell lines including (a) ovarian cancer cell lines ES-2, PA-1, CAOV-3, OVCAR-3, (b) testicular cancer cell lines Ntera-2, Tera-2, N2NICP, 833K, and 64CP, (c) multiple myeloma cell lines ARH77, HS-Sultan, RPMI-8226, and U266, and (d) acute lymphoblastic leukemia (ALL) cell lines NALM-6, MOLT-3, ALL-1, and RS4; 11, was determined by the MTT assay. The lead compounds, 2-methylthio-4-[(4'-aminophenylazo)-phenylarsonic acid] pyrimidine (PHI-370) and 2-methylthio-4-(4'-phenylarsonic acid)-aminopyrimidine (PHI-380) caused apoptotic death in all 17 cancer cell lines at low micromolar concentrations, as documented by TUNEL assays and confocal laser scanning microscopy. PHI-380 was also tested and found to be very active against primary tumor cells isolated from surgical biopsy specimens of 14 patients with therapy-refractory non-small cell lung cancer, breast cancer, colon cancer, lymphoma, hepatoblastoma, or Wilm's tumor as well. Because of their broad-spectrum and potent anticancer activity and ability to induce apoptosis in primary tumor cells from therapy-refractory cancer patients, PAA compounds such as PHI-370 and PHI-380 may provide the basis for effective salvage regimens for patients with recurrent cancer.
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PMID:Phenylarsonic acid compounds with broad-spectrum and potent cytotoxic activity against human cancer cells. 1287 14

Human carcinoembryonic antigen (CEA) is overexpressed in most colorectal cancers and has been widely used as a clinical marker for the management of colon cancer patients. The transcriptional regulatory elements (TREs) of CEA include two enhancer elements and a promoter in the 5'-flanking region of the CEA gene. By using these elements in different combinations to control reporter gene expression and the replication of adenovirus variants in various tumor cells, we have identified an optimal CEA regulatory cassette that tightly controls gene expression and viral replication in CEA-producing colon cancer cells. One of these variants, OV798, in which this regulatory cassette controls E1A expression, was further characterized. OV798 preferentially replicates in and kills CEA-producing colorectal cancer cell lines such as LoVo and SW1463, but its replication is attenuated by 1000-fold in the CEA-negative cell lines Colo-320DM (colon cancer), PA-1 (ovarian cancer), G361 (melanoma), U118 MG (glioma), and HBL-100 (human breast epithelial cell). The antitumor activity of OV798 was further examined in BALB/c nu/nu mice carrying s.c. human colon tumor xenografts. A single intratumoral administration of OV798 resulted in growth inhibition of human LoVo colon cancer xenografts. Six weeks after treatment, relative tumor volume decreased to 90% of baseline for the OV798 treatment group, compared to an increase to 1200% of baseline at 4 weeks for the vehicle-treated group. In vitro and in vivo characterization indicate that OV798 could be used as a therapy for human colon cancer.
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PMID:Carcinoembryonic antigen-producing cell-specific oncolytic adenovirus, OV798, for colorectal cancer therapy. 1457 65

Cyclin D1, encoded by the gene CCND1, is a major regulator of the cell cycle transition from G1 phase to S phase. A CCND1 polymorphism (G to A) at codon 242, the boundary of exon 4 and intron 4, affects splicing such that exon 5 is not expressed in the A allele. Since exon 5 is involved in rapid turnover, the variant cyclin D1 corresponding to the A allele may have a longer half-life. A previous study demonstrated that in families with hereditary nonpolyposis colorectal cancer, the age of onset of colorectal cancer varied according to variation at this polymorphic site. We examined this CCND1polymorphism in a series hepatoblastoma, a childhood liver cancer that shares other molecular features with colon cancer. We determined in an analysis of 84 children with hepatoblastoma that the G/A exon 4 polymorphism in CCND1 is correlated with the age of onset of hepatoblastomas. The A/A genotype is associated with an earlier age of onset compared to the G/A or G/G genotype. The median age of patients with the G/G genotype was 22 months, compared to 17 months in patients with the G/A genotype and 11 months for the A/A genotype. These findings suggest that the CCND1 A polymorphism may contribute to tumor development in children with hepatoblastoma.
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PMID:CCND1 polymorphism and age of onset of hepatoblastoma. 1513 90

Two brothers with hepatoblastoma were noted to have a family history of early onset colon cancer. Genetic testing of the younger brother revealed a deletion in exon 15 of the adenomatous polyposis coli (APC) gene (2710-2711delAG), consistent with a diagnosis of familial adenomatous polyposis (FAP). We review the clinical and molecular aspects of the relationship between hepatoblastoma and FAP, and the implications for diagnostic testing and cancer screening in affected patients.
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PMID:Familial adenomatous polyposis in two brothers with hepatoblastoma: implications for diagnosis and screening. 1610 29


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