Alan Hewer

p53-dependent global nucleotide excision repair of cisplatin-induced intrastrand cross links in human cells (2008)

Bhana, Sara, Hewer, Alan, Phillips, David H., Lloyd, Daniel R.

Cisplatin is an extremely effective chemotherapeutic agent used for the treatment of testicular and other solid tumours. It induces a variety of structural modifications in DNA, the most abundant...

A biomarker model of sublethal genotoxicity (DNA single-strand breaks and adducts) using the sentinel organism Aporrectodea longa in spiked soil. (2005)

Martin, Francis L., Piearce, Trevor G., Hewer, Alan, Phillips, David H., Semple, Kirk T.

There is a need to develop risk biomarkers during the remediation of contaminated land. We employed the earthworm, Aporrectodea longa (Ude), to determine whether genotoxicity measures could be...

Organ specificity of DNA adduct formation by tamoxifen and {alpha}-hydroxytamoxifen in the rat: implications for understanding the mechanism(s) of tamoxifen carcinogenicity and for human risk assessment (2005)

Phillips, David H., Hewer, Alan, Osborne, Martin R., Cole, Kathleen J., Churchill, Cyd, Arlt, Volker M.

Tamoxifen is an anti-oestrogen widely used in the adjuvant therapy of breast cancer and is also used as a prophylactic to prevent the disease in high-risk women. An increased risk of endometrial...

Hepatic DNA adduct dosimetry in rats fed tamoxifen: a comparison of methods (2005)

Schild, Laura J., Phillips, David H., Osborne, Martin R., Hewer, Alan, Beland, Frederick A., Churchwell, Mona I., ...

Liver homogenates from rats fed tamoxifen (TAM) in the diet were shared among four different laboratories. TAM–DNA adducts were assayed by high pressure liquid chromatography–electrospray tandem...

Hepatic DNA adduct dosimetry in rats fed tamoxifen: a comparison of methods (2005)

Schild, Laura J., Phillips, David H., Osborne, Martin R., Hewer, Alan, Beland, Frederick A., Churchwell, Mona I., ...

Liver homogenates from rats fed tamoxifen (TAM) in the diet were shared among four different laboratories. TAM-DNA adducts were assayed by high pressure liquid chromatography-electrospray tandem mass...

Organ specificity of DNA adduct formation by tamoxifen and {alpha}-hydroxytamoxifen in the rat: implications for understanding the mechanism(s) of tamoxifen carcinogenicity and for human risk assessment (2005)

Phillips, David H., Hewer, Alan, Osborne, Martin R., Cole, Kathleen J., Churchill, Cyd, Arlt, Volker M.

Tamoxifen is an anti-oestrogen widely used in the adjuvant therapy of breast cancer and is also used as a prophylactic to prevent the disease in high-risk women. An increased risk of endometrial...

Modulation of N-methyl-N-nitrosourea-induced crypt restricted metallothionein immunopositivity in mouse colon by a non-genotoxic diet-related chemical (2004)

Donnelly, Eilish T., Bardwell, Helen, Thomas, Geraldine Anne, Williams, E. Dillwyn, Hoper, Margaret, Crowe, Paul, ...

Red meat consumption is associated with endogenous metabolic generation of mutagenic N-nitroso compounds (NOC) and may be implicated in causation of colorectal cancer. Assessment of a biologically...

Modulation of N-methyl-N-nitrosourea (MNU) induced crypt restricted metallothionein (MT) immunopositivity in mouse colon by a non-genotoxic diet related chemical (2004)

Donnelly, Eilish T., Bardwell, Helen, Thomas, Geraldine Anne, Williams, E. Dillwyn, Hoper, Margaret, Crowe, Paul, ...

Red meat consumption is associated with endogenous metabolic generation of mutagenic N-nitroso compounds (NOC) and may be implicated in causation of colorectal cancer (CRC). Assessment of a...

Electrospray Ionization–Tandem Mass Spectrometry and 32P-Postlabeling Analyses of Tamoxifen–DNA Adducts in Humans (2004)

Beland, Frederick A., Churchwell, Mona I., Doerge, Daniel R., Parkin, Daniel R., Malejka-Giganti, Danuta, Hewer, Alan, ...

Background: Although the nonsteroidal antiestrogen tamoxifen is used as an adjuvant chemotherapeutic agent to treat hormone-dependent breast cancer and as a chemopreventive agent in women with...

Lack of evidence for tamoxifen- and toremifene-DNA adducts in lymphocytes of treated patients (2000)

Bartsch, Helmut, Phillips, David H., Nair, Jagadeesan, Hewer, Alan, Meyberg-Solomeyer, Gabriele, Grischke, Eva-Maria

Tamoxifen (TAM) is used for the adjuvant treatment of women with breast cancer and has also been recommended as a chemopreventive agent. Among unwanted side effects, TAM was shown to increase...

Pathways of heterocyclic amine activation in the breast: DNA adducts of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) formed by peroxidases and in human mammary epithelial cells and fibroblasts (2000)

Williams, J.Andrew, Stone, Elaine M., Millar, Barbara C., Hewer, Alan, Phillips, David H.

Most human mammary carcinomas originate in the epithelial cells of the breast ducts. A potential role of heterocyclic amines (HAs) in the aetiology of this disease has led us to investigate...

Metabolic proficiency and benzo[a]pyrene DNA adduct formation in APCMin mouse adenomas and uninvolved mucosa (1999)

Sattar, Abid, Hewer, Alan, Phillips, David H., Campbell, Frederick C.

Tumour formation may involve interactions between genetic factors and environmental carcinogens. Adenoma formation in APCMin/+ mice is associated homozygous adenomatous polyposis coli (APC) gene...

Idoxifene derivatives are less reactive to DNA than tamoxifen derivatives, both chemically and in human and rat liver cells (1999)

Osborne, Martin R., Hewer, Alan, Davis, Warren, Strain, Alastair J., Keogh, Adrian, Hardcastle, Ian R., ...

The drug tamoxifen shows evidence of genotoxicity, and induces liver tumours in rats. Covalent DNA adducts have been detected in the liver of rats treated with tamoxifen, and these arise through...

N-Demethylation accompanies {alpha}-hydroxylation in the metabolic activation of tamoxifen in rat liver cells (1999)

Phillips, David H., Hewer, Alan, Horton, Martin N., Cole, Kathleen J., Carmichael, Paul L., Davis, Warren, ...

Previous work has shown that a major route of activation of tamoxifen to DNA-binding products in rat liver cells is via α-hydroxylation leading to modification of the N2-position of guanine in DNA...

p53mutations in lung tumours: relationship to gender and lung DNA adduct levels (1996)

Kure, Elin H., Ryberg, David, Hewer, Alan, Phillips, David H., Skaug, Vidar, Bæera, Rita, ...

Human lung cancer exhibits a high frequency of transver-sion mutations at G: C base pairs of the p53 gene, possibly the result of DNA damage by cigarette smoke constituents, most notably...

Activation of tamoxifen and its metabolite {alpha}-hydroxytamoxifen to DNA-binding products: comparisons between human, rat and mouse hepatocytes (1996)

Phillips, David H., Carmichael, Paul L., Hewer, Alan, Cole, Kathleen J., Hardcastle, Ian R., Poon, Grace K., ...

The metabolic activation of tamoxifen and its metabolite α-hydroxytamoxifen in primary cultures of rat, mouse and human hepatocytes has been compared. The extent of formation of DNA adducts in these...

Tamoxifen does not form detectable DNA adducts in white blood cells of breast cancer patients (1996)

Phillips, David H., Hewer, Alan, Grover, Philip L., Poon, Grace K., Carmichael, Paul L.

DNA from white blood cells of seven women receiving tamoxifen as adjuvant therapy for breast cancer and of three women who served as healthy controls was analysed for the presence of tamoxifen-DNA...

Co-chromatography of a tamoxifen epoxide-deoxyguanylic acid adduct with a major DNA adduct formed in the livers of tamoxifen-treated rats (1994)

Phillips, David H., Hewer, Alan, White, Ian N. H., Farmer, Peter B.

Tamoxifen is a potent liver carcinogen in rats and has been shown to form covalent DNA adducts in the livers of several species of rodent. We have shown previously by 32P-postlabelling...

Genotoxicity characteristics of reverse diol-epoxides of chrysene (1993)

Glatt, Hansruedi, Wameling, Christa, Elsberg, Sabine, Thomas, Helmut, Marquardt, Hans, Hewer, Alan, ...

Trans-3,4-dihydroxy-3,4-dihydrochrysene (chrysene-3,4-diol), a major metabolite of chrysene, is further metabolized by rat liver enzymes to products which effectively revert the his− Salmonella...

Interaction of omeprazole with DNA in rat tissues (1992)

Phillips, David H., Hewer, Alan, Osborne, Martin R.

There has been concern recently over the possible genotoxicity of omeprazole, a potent inhibitor of gastric acid secretion in humans. In order to investigate its possible DNA binding activity in...

Genotoxic potential of tamoxifen and analogues in female Fischer F344/n rats, DBA/2 and C57BL/6 mice and in human MCL-5 cells (1992)

White, Ian N.H., De Matteis, Francesco, Davies, Adrian, Smith, Lewis L., Crofton-Sleigh, Christopher, Venitt, Stanley, ...

Chronic administration of tamoxifen to female rats causes hepatocellular carcinomas. We have investigated damage to liver DNA caused by the administration of tamoxifen to female Fischer F344/N...

Evaluation of DNA-binding activity of hydroxyanthraquinones occurring in Rubia tinctorum L (1991)

Poginsky, Barbara, Westendorf, Johannes, Blömeke, Brunhilde, Marquardt, Hans, Hewer, Alan, Grover, Philip L., ...

The naturally-occurring anthraquinones (AQs), alizarin (1,2-dihydroxyanthraquinone) and lucidin (1,3-dihydroxy-2-hydroxymethylanthraquinone), were incubated with DNA in the presence of S9 mix. The...

The metabolic activation of dibenz[a,h]anthracene in mouse skin examined by 32P-postlabelling: minor contribution of the 3,4-diol 1,2-oxides to DNA binding (1991)

Lecoq, Sophie, Ni She, Meadhbh, Hewer, Alan, Grover, Philip L., Platt, Karl L., Oesch, Franz, ...

Dibenz[a,h]anthracene (DB[a,h]A) and the related 3,4-diol and anti- and syn-3,4-diol 1,2-oxides were applied to the shaved dorsal skin of groups of four C57B1/CB1 mice. Twenty-four hours later the...

Tissue distribution of DNA adducts in CDF1 mice fed 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and 2-amino-3,4-dimethylimidazo[4,5-fquinoline (MeIQ) (1990)

Hall, Michael, Shé, Meadhbh Ni, Wild, Dieter, Fasshauer, Ingrid, Hewer, Alan, Phillips, David H.

Male and female CDF, mice were administered a single oral dose of 3 µmol of the food mutagens 2-amino-3-methyl-imidazo[4,5-f]quinoline (IQ) or 2-amino-3,4-dimethylimidazo [4,5-f]quinoline (MeIQ) and...

32P-Postlabelling analysis of DNA adducts in the skin of mice treated with petrol and diesel engine lubricating oils and exhaust condensates (1989)

Schoket, Bernadette, Hewer, Alan, Grover, Phillip L., Phillips, David H.

Samples of unused or used petrol and diesel engine lubricating oils were applied to the shaved dorsal skin of 4- to 6-week-old male Parkes mice, either as a single treatment (50 μ/mouse) or as four...

Enzyme-mediated phosphorylation of polycyclic hydrocarbon metabolites: detection of non-adduct compounds in the 32P-postlabelling assay (1989)

Masento, Mark S., Hewer, Alan, Grover, Philip L., Phillips, David H.

32P-Postlabelling analysis is a sensitive method of detecting covalent modification of DNA by chemical carcinogens. We demonstrate that tetrol derivatives of the polycyclk aromatic hydrocarbons...

Covalent binding of components of coal-tar, creosote and bitumen to the DNA of the skin and lungs of mice following topical application (1988)

Schoket, Bernadette, Hewer, Alan, Grover, Philip L., Philips, David H.

In order to assess the DNA damaging ability of complex carcinogenic mixtures, male Parkes mice were treated topically with solutions of (i) pharmaceutical coal-tar, (ii) creosote, a blend of coal-tar...

Aromatic DNA adducts in human bone marrow and peripheral blood leukocytes (1986)

Phillips, David H., Hewer, Alan, Grover, Philip L.

DNA from normal human bone marrow mononuclear and non-mononuclear cells was analysed by 32P-post-labelling for the presence of aromatic adducts. Ten out of 10 individuals showed the presence of...