Publications by authors named "Cotter T"

Background: The aim of this study was to evaluate feasibility and tolerability of the three-drug combination of paclitaxel, ifosfamide and carboplatin (TIC) in patients with advanced non-small-cell lung cancer. The specific objectives of the study were: (i) to define the dose-limiting toxicities (DLTs) and the maximum-tolerated dose of ifosfamide administered as part of the combination; and (ii) to determine the overall response rate and overall survival of patients treated with this regimen.

Patients And Methods: Patients with untreated, stage IIIB (pleural effusion) or stage IV non-small-cell lung cancer were enrolled in one of three cohorts.

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Despite the high incidence and mortality rate of prostate cancer, the molecular mechanisms underlying the progression of the disease remain to be fully elucidated. This paper reviews the current state of knowledge on prostatic carcinogenesis, focusing not only on the molecular genetics of prostate cancer, but also on the role of oncogenes, tumour suppressor genes, and growth factors. The remarkable ability of prostate cancer cells to survive androgen withdrawal and apoptosis are discussed, with particular emphasis on how apoptosis may be manipulated from a therapeutic viewpoint.

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Motivation: Most supervised classification methods are limited by the requirement for more cases than variables. In microarray data the number of variables (genes) far exceeds the number of cases (arrays), and thus filtering and pre-selection of genes is required. We describe the application of Between Group Analysis (BGA) to the analysis of microarray data.

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Apoptosis is the mode of photoreceptor cell death in many retinal dystrophies. Exposure of Balb/c mice to excessive levels of light induces photoreceptor apoptosis and represents an animal model for the study of retinal degenerations. Caspases have emerged as central regulators of apoptosis, executing this tightly controlled death pathway in many cells.

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Treatment of the hormone refractory prostate cancer cell line DU 145 with sublethal concentrations of chemotherapeutic drugs has been reported to sensitise these cells to Fas mediated apoptosis. However, the mechanism by which this occurs has not been determined. Our group has shown that inhibition of JNK activity completely abrogates the effects of chemotherapeutic drugs.

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Bcr-Abl is a constitutively active tyrosine kinase involved in the development and progression of chronic myeloid leukaemia (CML). It has been demonstrated that Bcr-Abl-positive cells can be uniquely resistant to apoptosis induced by different types of stimuli, but the mechanism by which this is achieved is not defined. In this study we have investigated how cells expressing high expression levels of Bcr-Abl may gain resistance to cytotoxic drugs.

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Cells are constantly generating reactive oxygen species (ROS) during aerobic metabolism. As a consequence, each cell is equipped with an extensive antioxidant defence system to combat excessive production of ROS. Oxidative stress occurs in cells when the generation of ROS overwhelms the cell's natural antioxidant defences.

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The chimaeric BCR-ABL oncoprotein is the molecular hallmark of chronic myeloid leukaemia (CML). Expression of Bcr-Abl has been associated with arrested differentiation as well as resistance to apoptosis. The downstream pathway involved in apoptosis resistance has been extensively studied, whereas the role of Bcr-Abl in cell differentiation is largely unclear.

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Erythrocytes have a defined lifespan in vivo, and the signals that maintain their survival in circulation or trigger their death are unknown. Here, we investigated the control of erythrocyte survival and death in an in vitro culture system where erythrocytes survived for 10 days in serum-free medium in the presence or absence of bovine serum. Death of the cells in culture was correlated with increased exposure of phosphatidylserine and increased levels of intracellular calcium.

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A characteristic feature of chronic myeloid leukaemia (CML) is the inevitable advancement from a treatable chronic phase to a fatal, drug-resistant stage referred to as blast crisis. The molecular mechanisms responsible for this disease transition remain unknown. As increased expression of Bcr-Abl has been associated with blast crisis CML, we have established transfectants in 32D cells that express low and high levels of Bcr-Abl, and assessed their drug sensitivity.

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The synthetic peptide PrP-(106-126) has previously been shown to be neurotoxic. Here, for the first time, we report that it induces apoptosis in the human neuroblastoma cell line SH-SY5Y. The earliest detectable apoptotic event in this system is the rapid depolarization of mitochondrial membranes, occurring immediately upon treatment of cells with PrP-(106-126).

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The purpose of this study was to compare the independent and interactive effects of age and exercise training on selected parameters of the right ventricle (RV), left ventricular septum (LVS) and left ventricular free-wall (LVFW) extracellular matrix. Specifically, we evaluated collagen and collagen crosslinking (hydroxylysylpyridinoline, HP) concentrations in the myocardial extracellular matrix in young adult, Y (5.5 months) and old, O (25.

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To explore the possible influence of defined genetic backgrounds on photoreceptor viability and function in mice carrying a targeted disruption of the rhodopsin gene, the severities of retinopathies in Rho-/- mice on C57BL/6J and 129Sv congenic backgrounds were compared by light microscopy and electroretinography and qualitatively by in situ end labeling of DNA in apoptotic photoreceptor nuclei of retinal sections. Cone photoreceptor viability and function were shown to deteriorate more slowly on the C57BL/6J background in comparison to that of the 129Sv, with significantly greater numbers of outer nuclear layer nuclei in the retinas of C57BL/6J mice at 3 and 4 months of age. Both amplitude and waveform features of the ERG were shown to be remarkably different in the two strains, indicating an approximately 6-fold difference in C57BL/6J Rho-/- mice compared to 129Sv Rho-/- mice at 80 days.

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Increasing resistance to chemotherapeutic regimes remains a serious problem in the treatment of acute myeloid leukaemia. We have shown that phosphatidylinositol (PI) 3-kinase inhibition significantly sensitises the AML derived cell line, HL60 to chemotherapeutic drug- and Fas-induced apoptosis. PI3-kinase inhibition significantly potentiates cytotoxic drug-induced c-jun N-terminal kinase (JNK) activation, reported to be a requirement for apoptosis.

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Reactive oxygen species (ROS) are frequently associated with cytotoxicity, often being described as damaging, harmful or toxic. It is generally assumed that, under pathological circumstances, ROS elicit wide-spread and random acts of oxidation. This passive attack of cellular components by ROS, in conditions where oxidative stress is the initiating stimulus for apoptosis, is assumed to simply trigger cell death as a result of cumulative oxidative damage.

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Interactions between proteins of the Bcl-2 family play an important role in the regulation of apoptosis. Anti-apoptotic family members can heterodimerize with pro-apoptotic family members and antagonize their function, thus protecting against death. In cells protected from death by overexpression of Bcl-2 much of the Bax is present in Bax/Bcl-2 hetero-multimers and its death signal is blocked as it cannot homodimerize.

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Apoptosis is the mode of photoreceptor cell death in inherited and induced retinal degeneration. However, the molecular mechanisms of photoreceptor cell death in human cases and animal models of retinal dystrophies remain undefined. Exposure of Balb/c mice to excessive levels of white light results in photoreceptor apoptosis.

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Drug resistance, to date, has primarily been attributed to increased drug export or detoxification mechanisms. Despite correlations between drug export and drug resistance, it is increasingly apparent that such mechanisms cannot fully account for chemoresistance in neoplasia. It is now widely accepted that chemotherapeutic drugs kill tumour cells by inducing apoptosis, a genetically regulated cell death programme.

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Chronic myeloid leukemia (CML) is a disease of the hematopoietic system, characterized by the presence of the Bcr-Abl oncoprotein. The main characteristics of this disease include adhesion independence, growth factor independence, and resistance to apoptosis. Loss or mutation of the tumor suppressor gene, p53, is one of the most frequent secondary mutations in CML blast crisis.

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A combined total of approximately 100 mutations have been encountered within the rhodopsin gene in retinitis pigmentosa (RP) and congenital night blindness. Mice carrying a targeted disruption of the rhodopsin gene phenotypically mimic RP, losing their photoreceptors over a period of 3 months and having no recordable rod electroretinogram. These animals will serve as a model for both recessive and dominant disease (in the latter case, the presence of normal and mutant human rod opsin transgenes on the murine Rho(-/-)background).

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Apoptosis is a genetically programmed, physiological method of cell destruction. A variety of genes are now recognised as positive or negative regulators of this process. Expression of inducible heat shock proteins (hsp) is known to correlate with increased resistance to apoptosis induced by a range of diverse cytotoxic agents and has been implicated in chemotherapeutic resistance of tumours and carcinogenesis.

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Heat shock protein 70 (hsp70) is a stress-inducible protein that prevents apoptosis induced by a wide range of cytotoxic agents by an as yet undefined mechanism. The caspase family of cysteine proteases have been attributed a central role in the execution of apoptosis. However, several cases of caspase-independent apoptosis have been recently reported, suggesting that caspases may not be necessary for apoptosis in all cells.

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