• A novel circulating tumour cell-derived xenograft (CDX) model to investigate uveal melanoma metastasis.

      Mahal, Katharina; Lee, Rebecca J; Garcia-Martinez, Pablo; Smith, Matthew; Dhomen, Nathalie; Marais, Richard; Univ Manchester, Manchester Canc Res Ctr, Manchester, Lancs, England (2018)
    • A simple one-pot preparation of 4-alkoxy and 4-alkylthio-catechols and o-benzoquinones.

      Cooksey, C J; Land, Edward J; Department of Chemistry, University College London, London, UK (1996)
    • Abarelix and other gonadotrophin-releasing hormone antagonists in prostate cancer.

      Kirby, Roger S; Fitzpatrick, John M; Clarke, Noel W; The Prostate Centre, London, UK. (2009-12)
      Hormonal therapy is the main recommended treatment for locally advanced and metastatic prostate cancer. Luteinizing hormone-releasing hormone (LHRH) agonists, such as buserelin, goserelin, leuprorelin and triptorelin, stimulate the pituitary's gonadotrophin-releasing hormone (GnRH) receptor, ultimately leading to its de-sensitization and subsequent reduction of LH and testosterone levels. However, this reduction is accompanied by a well described increase or 'surge' in LH and testosterone levels, necessitating the concomitant administration of an antiandrogen to combat the potential effects of transient acceleration in cancer activity. Two pure GnRH antagonists have been developed, abarelix and degarelix, that are devoid of any agonist effect on the GnRH receptor and consequently do not result in testosterone flare. Abarelix was the first GnRH antagonist to be developed and was approved by the USA Food and Drug Administration in 2004 for the initiation of hormonal castration in advanced or metastasizing hormone-dependent prostate carcinoma, when rapid androgen suppression is necessary. Clinical data on both abarelix and degarelix show that they can produce rapid and sustained decreases in testosterone to castrate levels without the need for co-administration of an antiandrogen, and with a very low complication rate in the short term.
    • Abatacept acute graft-versus-host disease prophylaxis is feasible and safe when combined with post-transplant cyclophosphamide in the mobilised peripheral blood haploidentical donor setting

      Yong, J.; Patel, Alkesh; Haematology, Clatterbridge Cancer Centre, Liverpool (2020)
      Acute graft-versus-host disease (aGVHD) remains a major limitation to allogeneic haematopoietic stem cell transplantation (HSCT), associated with high patient morbidity and mortality. Steroid refractory acute GVHD (SR-aGVHD) has the highest mortality (around 80%) despite treatment intensi'cation with available immunosuppressive therapy. This is complicated by poor response rates alongside increased toxicity and infectious complications from profound immunosuppression and prolonged uncontrolled GVHD. Novel immunotherapeutic strategies are therefore urgently needed for treatment of SR-aGVHD. Immunological manipulation of T-cell activation is a novel therapeutic treatment approach for aGVHD. Abatacept, a CTLA4-Ig exerting CD28-CD80/CD86 axis T-cell co-stimulation blockade, has been shown in the phase 1 clinical trial setting to be safe, well tolerated without dose limiting toxicities (DLTs), and ef'cacious in the treatment of heavily pretreated chronic extensive GVHD (cGVHD). Marked improvement in National Institutes of Health cGVHD scores alongside signi'cantly reduced steroid dose requirement in this cohort have led to a phase 2 trial (NCT01954979) and National Comprehensive Cancer Network (NCCN) recommendation. T-cell activation is a key component of aGvHD but it is currently unknown if Abatacept represents a potential therapy for SR-aGVHD. We report the feasibility, safety and ef'cacy of Abatacept added to the management of SR-aGVHD in a cohort of four heavily pretreated patients in a single centre. Institutional compassionate access was granted after exhaustion of all available therapies. Three of the four patients developed aGvHD after donor lymphocyte infusion (DLI), in the absence of pre-DLI conditioning or GVHD prophylaxis. Median overall MAGIC aGVHD score was 4, with two patients having predominant stage 4 gut aGVHD and two patients with predominant stage 4 skin aGVHD. The median prior lines of treatment were 5, including steroid therapy (Prednisolone or Methylprednisolone 2 mg/kg/day), calcineurin or mTOR inhibitor, mycophenolic acid and extracorporeal photophoresis (ECP) with 8methoxypsoralen (8-MOP). Patients with gut aGVHD were also treated with vedolizumab and/or in'iximab. Abatacept 10 mg/kg was administered IV in addition to concurrent treatments for SR-aGVHD at d0, d+14, d+28, d+56, d+72 and d+90. If a clinical response was observed after 6 doses, Abatacept was continued every 4'6 weeks up to 12 doses. Two patients achieved a clinical partial response and one patient a clinical complete response at d+100 after initiation of Abatacept. Importantly all patients achieved a median dose reduction in steroids of 98% by d+100. Three patients had viral reactivation diagnosed prior to Abatacept initiation (median of d'155 before Abatacept). Importantly, no new viral reactivations were detected in any patients after Abatacept initiation. No DLTs were observed; bacterial infections were not considered a DLT if they had already occurred with prior therapies, being attributed to pre-existing severe immunosuppression and SRaGVHD. We observed that patients with less than CR by d+100 developed chronic GVHD of the involved organ. Mortality was observed only in the two patients with gut involvement, as a result of chronic malnutrition and recurrent immunocompromised infection. Our experience suggests that Abatacept for SR-aGvHD is feasible, appears safe and may have ef'cacy in some patients. A prospective clinical trial is planned.
    • Aberrant activation of notch signaling in human breast cancer.

      Stylianou, Spyros; Clarke, Robert B; Brennan, Keith; Wellcome Trust Centre for Cell Matrix Research, Faculty of Life Sciences, University of Manchester, Christie Hospital NHS Trust, Manchester M13 9PT, United Kingdom. (2006-02-01)
      A role for Notch signaling in human breast cancer has been suggested by both the development of adenocarcinomas in the murine mammary gland following pathway activation and the loss of Numb expression, a negative regulator of the Notch pathway, in a large proportion of breast carcinomas. However, it is not clear currently whether Notch signaling is frequently activated in breast tumors, and how it causes cellular transformation. Here, we show accumulation of the intracellular domain of Notch1 and hence increased Notch signaling in a wide variety of human breast carcinomas. In addition, we show that increased RBP-Jkappa-dependent Notch signaling is sufficient to transform normal breast epithelial cells and that the mechanism of transformation is most likely through the suppression of apoptosis. More significantly, we show that attenuation of Notch signaling reverts the transformed phenotype of human breast cancer cell lines, suggesting that inhibition of Notch signaling may be a therapeutic strategy for this disease.
    • Aberrant CDKN1A transcriptional response associates with abnormal sensitivity to radiation treatment.

      Badie, Christophe; Dziwura, S; Raffy, C; Tsigani, Theodora; Alsbeih, G; Moody, J; Finnon, Paul; Levine, Edward; Scott, David A; Bouffler, Simon; et al. (2008-06-03)
      Normal tissue reactions to radiation therapy vary in severity among patients and cannot be accurately predicted, limiting treatment doses. The existence of heritable radiosensitivity syndromes suggests that normal tissue reaction severity is determined, at least in part, by genetic factors and these may be revealed by differences in gene expression. To test this hypothesis, peripheral blood lymphocyte cultures from 22 breast cancer patients with either minimal (11) or very severe acute skin reactions (11) have been used to analyse gene expression. Basal and post-irradiation expression of four radiation-responsive genes (CDKN1A, GADD45A, CCNB1, and BBC3) was determined by quantitative real-time PCR in T-cell cultures established from the two patient groups before radiotherapy. Relative expression levels of BBC3, CCNB1, and GADD45A 2 h following 2 Gy X-rays did not discriminate between groups. However, post-irradiation expression response was significantly reduced for CDKN1A (P<0.002) in severe reactors compared to normal. Prediction of reaction severity of approximately 91% of individuals sampled was achieved using this end point. Analysis of TP53 Arg72Pro and CDKN1A Ser31Arg single nucleotide polymorphisms did not show any significant association with reaction sensitivity. Although these results require confirmation and extension, this study demonstrates the possibility of predicting the severity of acute skin radiation toxicity in simple tests.
    • Ability to undergo apoptosis does not correlate with the intrinsic radiosensitivity (SF2) of human cervix tumor cell lines.

      Sheridan, Mary T; West, Catharine M L; CRC Experimental Radiation Oncology Group, Paterson Institute for Cancer Research, Christie Hospital NHS Trust, Manchester, United Kingdom. (2001-06-01)
      PURPOSE: To investigate the relationship between radiation-induced apoptosis and clonogenic cell kill in 9 cervical cancer cell lines. METHODS AND MATERIALS: Cells were irradiated with 0, 2, 8, and 30 Gy. The level of apoptosis was evaluated using flow cytometry (Annexin-V binding), light microscropy (morphology), gel electrophoresis (DNA ladder formation), and TUNEL assay. Cell survival was measured using a clonogenic assay. RESULTS: Of the 9 cervical carcinoma cell lines analyzed, 3 underwent radiation-induced apoptosis: CaSki, HT3, and 778. The levels of apoptosis, obtained 72 h after a dose of 30 Gy, were 49%, 28%, and 26%, respectively. All cell lines exhibited some level of background apoptosis measured by Annexin-V binding (mean = 2.6%+/-0.8; range, 0.2-6.9%) that correlated with the level of radiation-induced apoptosis (r = 0.92, p = 0.001). In 6 of the 9 lines, necrosis was the dominant form of cell death. A significant inverse relationship was found between the level of radiation-induced apoptosis and necrosis after 30 Gy (r = -0.87, p = 0.002). No relationship was found between radiation-induced apoptosis and intrinsic radiosensitivity measured, using a clonogenic assay, as surviving fraction at 2 Gy (SF2). CONCLUSION: Cervical carcinoma cells do not readily undergo radiation-induced apoptosis in vitro. There is no relationship between ability to undergo apoptosis and intrinsic radiosensitivity measured using a clonogenic assay.
    • Abl protein kinase abrogates the response of multipotent haemopoietic cells to the growth inhibitor macrophage inflammatory protein-1 alpha.

      Wark, G; Heyworth, Clare M; Spooncer, Elaine; Czaplewski, L; Francis, Julia M; Dexter, T Michael; Whetton, Anthony D; Leukaemia Research Fund Cellular Development Unit, UMIST, Manchester, UK. (1998-03-12)
      The clonogenic cells of chronic myeloid leukaemia (CML), unlike normal haemopoietic progenitor cells, are resistant to the growth inhibitory effects of the chemokine macrophage inflammatory protein-1 alpha (MIP-1alpha). CML is also relatively resistant to chemotherapy and the disease is difficult to cure using conventional therapeutic routes. CML is associated with increased abl oncogene protein tyrosine kinase (PTK) activity. Here, we have tested the hypothesis that these aberrant responses to MIP-1alpha and the relative resistance to chemotherapy are directly related to this increased abl PTK activity in primitive haemopoietic cells. To do this we have expressed a temperature sensitive abl PTK in a growth factor dependent, multipotent stem cell line (FDCP-Mix) in which growth is normally suppressed by MIP-1alpha. In FDCP-Mix cells expressing the ts v-abl PTK and grown at the restrictive temperature for PTK activity the cells were relatively sensitive to cytotoxic agents such as cytosine arabinoside and 5-fluorouracil but MIP-1alpha could induce growth inhibition and confer some degree of protection from these agents. At the permissive temperature for abl PTK, the cells were relatively resistant to cytotoxic drugs and MIP-1alpha treatment neither induced growth inhibition nor protected the cells from cytotoxic drug induced cell death. This lack of response to MIP-1alpha was not due to receptor down modulation as neither the affinity nor the number of 125I-MIP-1alpha binding sites was altered by activating Abl PTK. However, MIP-1alpha mediated increases in cytosolic Ca2+ levels were abrogated by switching cells to the permissive temperature for Abl PTK activity. These data suggest that the relative resistance of CML progenitor cells to therapeutic drugs and the lack of response to MIP-1alpha occurs as a direct consequence of abl PTK activity and involves desensitisation of signal transduction events stimulated by MIP-1alpha receptors. Thus one contributory mechanism to transformation of primitive haemopoietic cells is abrogation of response to a growth inhibitor.
    • Ablation of murine jejunal crypts by alkylating agents.

      Moore, James V; Paterson Laboratories, Christie Hospital and Holt Radium Institute, Manchester (1979-02)
      The gut microcolony assay has been used to measure damage to intestinal crypts by single and split doses of 3 alkylating agents: mechlorethamine hydrochloride (HN2), bis-chloroethyl-nitrosourea (BCNU) and isopropyl methane sulphonate (IMS). The single-dose survival curves for whole crypts were distinguished by extrapolation numbers (3.0, 176 and 1.5 respectively) that were lower than most previously published values for assay by irradiation. Significant sparing of crypts occurred when doses of HN2 or BCNU, but not IMS, were given in 2 equal fractions separated by more than 2 h. Deduced D0 values for those cells from which crypts regenerate were 1.9 mg/kg HN2, 19 mg/kg BCNU and 487 mg/kg IMS.
    • The abnormal cytotoxicities of 2,5-diaziridinyl-1,4-benzoquinone-3-phenyl esters.

      Di Francesco, A; Hargreaves, R; Wallace, T; Mayalarp, Stephen P; Hazrati, A; Hartley, J; Butler, John; Department of Biological Sciences, Salford University, UK. (2000-10)
      Several derivatives of 2,5-diaziridinyl-3-phenyl-1,4-benzoquinone have been synthesized and their cytotoxicities in six different human cancer cell lines (H460, H596, HT29, BE, K562 and A2780) have been determined. It was observed that certain phenol-ester derivatives were significantly more cytotoxic in all of the cell lines investigated. These esters were shown to be cleaved by esterases to form a stable meta-phenol and an unstable para-phenol. The meta-phenol was also highly cytotoxic. Several of these compounds were studied in detail using DNA cross-linking, clonogenic, apoptosis and flow cytometry assays. It is proposed that although the phenol-esters and the phenols can efficiently cross-link DNA, this mechanism alone is not sufficient to explain the toxicities of these compounds.
    • Abnormal expression of CCND1 and RB1 in resection margin epithelia of lung cancer patients.

      Betticher, Daniel C; Heighway, Jim; Thatcher, Nick; Hasleton, Philip S; CRC Department of Med. Oncology, Christie Hospital (NHS) Trust, Manchester, UK. (1997)
      Tumours develop through the accumulation of genetic alterations associated with a progressive increase of the malignant phenotype. In lung cancer, chronic exposure of bronchial epithelium to carcinogens in cigarette smoke may lead to multiple dysplastic and hyperplastic lesions scattered throughout the tracheobronchial tree. Little is known about the genetic alterations in such lesions. This study was carried out to examine cyclin D1 (CCND1) and retinoblastoma (RB1) gene expression in the bronchial epithelium of patients with lung cancer. Lung tumours and their corresponding tumour-free resection margins from 33 patients who underwent resection of non-small-cell lung cancer (NSCLC) were examined by immunostaining with monoclonal antibodies against cyclin D1 (DCS-6; Novocastra) and pRb (NCL Rb-1; Novocastra). Examination of the resection margins revealed four carcinomas in situ, 19 hyperplasias and ten sections showing apparently normal bronchial epithelium. A control group of patients, without lung tumours and who had never smoked, revealed no or weak cyclin D1 and positive pRb staining within bronchial epithelia. Increased cyclin D1 and diminished pRb expression were found in 76% (n = 25) and 27% (n = 9) of the resection margins respectively, and in 12% (n = 4) both cyclin D1 and pRb expression were altered. In the corresponding tumours, 48% (n = 16) were normal, while altered expression was found for cyclin D1 in 33% (n = 11), pRb in 27% (n = 9) and both in 9% (n = 3) of cases. It appears that altered expression of cyclin D1 and pRb is an early event in NSCLC development in almost half of cases analysed. Further investigations are needed to determine the significance of immunostaining of bronchial specimens in individuals at risk of lung cancer, with the possibility that the observations are of importance in the early diagnosis of NSCLC.
    • Abnormal intracellular distribution of O6-alkylguanine-DNA-alkyltransferase in hepatitis B cirrhotic human liver: a potential cofactor in the development of hepatocellular carcinoma.

      Lee, Siow Ming; Portmann, B C; Margison, Geoffrey P; CRC Department of Carcinogenesis, Paterson Institute for Cancer Research, Manchester, UK. (1996-11)
      The expression of O6-alkylguanine-DNA-alkyltransferase (ATase), which is responsible for repair of the promutagenic and cytotoxic DNA lesion O6-alkylguanine, was examined by immunostaining in a series of liver sections from normal and hepatitis-B cirrhosis patients using a polyclonal anti-human ATase antiserum. In 10 normal liver sections, the ATase staining was predominantly nuclear and very intense in the majority of the hepatocytes with a panacinar distribution. In contrast, in 15 hepatitis-B sections, the ATase was located mainly in the cytoplasm of the majority of the hepatocytes and had a perinuclear distribution. Scattered hepatocytes showed a more intense staining involving all or part of their cytoplasm; nuclear staining, however, was reduced in intensity, being inconspicuous in seven and patchy and weak in eight. ATase activity in extracts of 10 of the hepatitis-B livers varied from approximately 90 to 360 fmoles/mg protein and there was no apparent relationship between these levels and the cellular distribution of the enzyme. The sequestration of the ATase protein in the cytoplasm, away from its site of action in the cell nucleus suggests that in hepatitis-B cirrhosis, the repair of O6-alkylguanine lesions by ATase may be less efficient than in normal hepatocytes. The abnormal cellular distribution of ATase may thus be an additional cofactor in the development of hepatitis-B-associated hepatocellular carcinoma.
    • Abnormal radiosensitivity of lymphocytes from breast cancer patients with excessive normal tissue damage after radiotherapy: chromosome aberrations after low dose-rate irradiation.

      Jones, L A; Scott, David; Cowan, Richard A; Roberts, Stephen A; Paterson Institute for Cancer Research, Christie CRC Research Centre, Manchester, UK. (1995-05)
      There is a need for a simple, rapid assay for predicting normal tissue reactions in radiotherapy patients to reduce morbidity in sensitive patients and to allow dose escalation in resistant cases. Towards this goal we have investigated the gamma-ray sensitivity of lymphocytes from 16 breast cancer patients who had shown an exaggerated acute or late radiation reaction ('overreaction') of normal tissues after radiotherapy, using chromosome damage (dicentrics) as the endpoint because of its close relationship with cell killing. The use of a low dose-rate (LDR; 0.31 cGy min-1) was found to be better than a high dose-rate (170 cGy min-1) in discriminating between over-reactors and controls, as predicted (and here confirmed) from previous studies on ataxia-telangiectasia (A-T) homozygotes and heterozygotes. Five of seven patients with excessive early skin reactions (e.g. erythema, moist desquamation) showed abnormal radiosensitivity, manifested either as aberration yields above the control range after LDR exposure or as less sparing than controls. The average LDR yield for early over-reactions was significantly higher than for controls (p = 0.009) and average sparing was less (p = 0.0002). Two of 10 patients with late complications (fibrosis, telangiectasia) had LDR yields above the control range, but the average yield for late over-reactors was not significantly above that of controls. Unexpectedly, two patients (one early, one late reaction) had LDR aberration yields below the control range. Quantitatively our results are consistent with the notion that over-reacting breast cancer patients are carriers of the A-T gene. Pilot studies on controls showed that the sparing effect of LDR irradiation was increased by lowering the dose-rate to 0.13 cGy min-1 and by using micronuclei rather than metaphase damage as the endpoint. These modifications to the protocol will be used in a large-scale prospective study.
    • Abnormal regulation of the oestrogen receptor in benign breast lesions.

      Shoker, B S; Jarvis, C; Clarke, Robert B; Anderson, Elizabeth; Munro, C; Davies, M P; Sibson, D R; Sloane, J P; Department of Pathology, University of Liverpool, UK. b.s.shoker@Liverpool.ac.uk (2000-10)
      BACKGROUND: In normal breast tissue the oestrogen receptor (ER) and the proliferation associated antigen Ki67 are negatively associated, indicating that ER+ cells are non-dividing, or that the receptor is downregulated as cells enter cycle. This relation is completely or partially lost in many ER+ breast cancers and in in situ proliferations associated with an increased cancer risk, where coexpression of the two markers is often found. AIMS: To determine whether similar changes can be identified in other risk associated breast lesions. PATIENTS/METHODS: Paraffin wax blocks from 12 cases of lactational change, 21 apocrine metaplasias, 22 duct ectasias, 20 sclerosing adenosis, 20 fibroadenomas, 19 phyllodes tumours, 20 radial scars, 21 papillomas (15 solitary and six multiple), 15 gynaecomastias, and nine postmortem male breast tissues were retrieved. Immunohistochemistry was used to determine the expression of ER and dual labelling immunofluorescence was used to detect cells expressing both ER and Ki67. RESULTS: Increased numbers of ER+ cells were seen in sclerosing adenosis, radial scars, papillomas, fibroadenomas, and phyllodes tumours but not in apocrine cysts (where no ER+ cells were detected) or duct ectasia (where normal numbers were found). As in the normal breast, the proportion of ER+ cells increased with age in all lesions with the exception of fibroadenomas. Coexpression of ER and Ki67 was found in an increased proportion of cells of all risk associated lesions studied. ER+ cells were less likely to be dividing than ER- cells in all cases, although this was significant only for sclerosing adenosis. The data on sclerosing adenosis, radial scars, papillomas, and fibroadenomas are comparable with those reported previously in hyperplasia of usual type, whereas those in duct ectasia are similar to those of the normal breast. The findings in all lesions, however, differed from those in ductal carcinoma in situ, where proportions of ER+ and ER+/Ki67+ cells are higher and the relation between ER+ cell numbers and age is lost. Thus, the nature and degree of dysregulation of ER in benign breast lesions is broadly in accordance with the degree of risk of developing breast cancer with which they are associated. In gynaecomastia, the proportions of ER+ and ER+/Ki67+ cells were comparable with those seen in benign female breast lesions, but changes with age were not observed. However, the changes in gynaecomastia were similar to those seen in normal male breast. CONCLUSION: These findings are in keeping with the contention that the dissociation of ER and Ki67 expression is a very early change in the pathway to many breast cancers. However, this change might only have preneoplastic importance in the hormonal milieu of the female breast.
    • Abrogation of adriamycin toxicity in vivo by cycloheximide.

      Thakker, Nalin; Potten, Christopher S; CRC Department of Epithelial Biology, Paterson Institute of Cancer Research, Christie Hospital NHS Trust, Manchester, U.K. (1992-04-15)
      The processes involved in cell killing by Adriamycin (ADR) and other agents that interact with topoisomerase II are unclear. To investigate the mode of ADR cytotoxicity in vivo, we have investigated the effects of the protein synthesis inhibitor, cycloheximide (CH), on cell killing by ADR in the murine intestinal tract. We have used morphological criteria to assay the cell death. ADR rapidly induces cell death in this tissue that has the morphology of apoptosis or programmed cell death. CH, when administered immediately after ADR, reduced the incidence of cell death by approximately 81% at 3 hr and approximately 51% at 6 hr after treatment. The inhibitor was only effective when administered within 0.5 hr of ADR suggesting that critical events leading to cell death may occur during this period. The inhibitor did not interfere with the ADR uptake or retention. Significant positive correlation was observed between protein and DNA synthesis inhibition (as measured by precursor uptake) and apoptosis inhibition. CH delayed progression of cells through all phases of the cell cycle except mitosis. However, ADR also had a similar effect, suggesting that progression through the cell cycle is not necessary for the expression of apoptosis. The effectiveness of CH in apoptosis inhibition, even when administered 0.5 hr after the ADR, coupled with the rapid uptake of ADR by the intestinal epithelium suggests that the mode of inhibition is unlikely to be modulation of cellular targets of ADR such as topoisomerase II or inhibition of formation of ADR-topoisomerase II complex. These data indicate that topoisomerase II-interacting agents such as ADR may induce apoptosis; the processes leading to cell death in this situation are thought to be gene dependent and require protein synthesis for their expression. Thus, the cytoprotective effect of CH may be due directly to the inhibition of protein synthesis.
    • Absence of a fractionation effect in irradiated HeLa cells.

      Nias, A H; Swallow, A John; Keene, J P; Hodgson, B W; Paterson Laboratories, Christie Hospital and Holt Radium Institute, Manchester (1973-06)
    • Absence of mutations in the ATM gene in breast cancer patients with severe responses to radiotherapy.

      Appleby, J; Barber, J B; Levine, Edward; Varley, Jennifer; Taylor, A M; Stankovic, T; Heighway, Jim; Warren, C; Scott, David; CRC Department of Cancer Genetics, Paterson Institute for Cancer Research, Christie Hospital (NHS) Trust, Manchester, UK. (1997)
      The effectiveness of cancer radiotherapy is compromised by the small proportion (approximately 5%) of patients who sustain severe normal tissue damage after standard radiotherapy treatments. Predictive tests are required to identify these highly radiosensitive cases. Patients with the rare, recessively inherited, cancer-prone syndrome ataxia-telangiectasia (A-T) sustain extremely severe normal tissue necrosis after radiotherapy and their cultured cells are also highly radiosensitive. Clinically normal carriers (heterozygotes) of the A-T gene have an increased risk of breast cancer, account for approximately 4% of all breast cancer cases and show a modest increase in cellular radiosensitivity in vitro. It has been suggested that a substantial proportion of highly radiosensitive (HR) breast cancer patients may be A-T heterozygotes, and that screening for mutations in the A-T gene could be used as a predictive test. We have tested this hypothesis in a group of cancer patients who showed adverse reactions to radiotherapy. Sixteen HR breast cancer patients showing mainly acute reactions (and seven HR patients with other cancers) were tested for ATM mutations using the restriction endonuclease fingerprinting assay. No mutations typical of those found in obligate A-T heterozygotes were detected. If the estimate that 4% of breast cancer cases are A-T gene carriers is correct, then ATM mutations do not confer clinical radiosensitivity. These early results suggest that screening for ATM mutations in cancer patients may not be of value in predicting adverse reactions.
    • Absolute Quantification of Endogenous Ras Isoform Abundance.

      Mageean, C; Griffiths, J; Smith, Duncan L; Clague, M; Prior, I; Division of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool (2015)
      Ras proteins are important signalling hubs situated near the top of networks controlling cell proliferation, differentiation and survival. Three almost identical isoforms, HRAS, KRAS and NRAS, are ubiquitously expressed yet have differing biological and oncogenic properties. In order to help understand the relative biological contributions of each isoform we have optimised a quantitative proteomics method for accurately measuring Ras isoform protein copy number per cell. The use of isotopic protein standards together with selected reaction monitoring for diagnostic peptides is sensitive, robust and suitable for application to sub-milligram quantities of lysates. We find that in a panel of isogenic SW48 colorectal cancer cells, endogenous Ras proteins are highly abundant with ≥260,000 total Ras protein copies per cell and the rank order of isoform abundance is KRAS>NRAS≥HRAS. A subset of oncogenic KRAS mutants exhibit increased total cellular Ras abundance and altered the ratio of mutant versus wild type KRAS protein. These data and methodology are significant because Ras protein copy number is required to parameterise models of signalling networks and informs interpretation of isoform-specific Ras functional data.
    • Absolute versus relative measures of plasma fatty acids and health outcomes: example of phospholipid omega-3 and omega-6 fatty acids and all-cause mortality in women.

      Miura, K; Hughes, M; Ungerer, J; Smith, D; Green, Adèle C; Cancer and Population Studies Group, QIMR Berghofer Medical Research Institute, 300 Herston Road, Herston, Brisbane, QLD, 4006, Australia. (2016-12-19)
      In a well-characterised community-based prospective study, we aimed to systematically assess the differences in associations of plasma omega-3 and omega-6 fatty acid (FA) status with all-cause mortality when plasma FA status is expressed in absolute concentrations versus relative levels.
    • Absorption spectra of radical ions of polyenes of biological interest.

      Lafferty, J; Roach, A; Sinclair, R; Truscott, T George; Land, Edward J (1977)