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991.
Casein kinase II (CK2) enhances death-inducing signaling complex (DISC) activity in TRAIL-induced apoptosis in human colon carcinoma cell lines 总被引:2,自引:0,他引:2
Protein kinase casein kinase II (CK2) is increased in response to diverse growth stimuli, as well as being elevated in many human cancers examined. We have demonstrated that CK2 is a key survival factor that protects human colon carcinoma cells from TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis. We determined that inhibition of CK2 phosphorylation events by DRB (5,6-dichlorobenzimidazole) resulted in dramatic sensitization of tumor cells to TRAIL-induced apoptosis, in the absence of effects in normal cells. Sensitization was caspase dependent, and independent of regulation via NF-kappaB. Further, inhibition of phosphorylation by CK2 did not modify the expression level of antiapoptotic proteins. Analysis of TRAIL-induced death-inducing signaling complex (DISC) formation demonstrated enhanced formation of the DISC, enhanced cleavage of caspase-8 and cleavage of Bid in the presence of DRB, thereby facilitating the release of proapoptotic factors from the mitochondria with subsequent downregulation of the expression of XIAP and c-IAP1. Further, silencing of CK2alpha in HT29 cells following transfection of CK2alpha shRNA abrogated CK2 kinase activity while simultaneously increasing TRAIL sensitivity. These findings demonstrate that CK2 plays a critical antiapoptotic role by conferring resistance to TRAIL at the level of the DISC. 相似文献
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995.
Despite substantial contributions on the part of public, non-profit, and private sector organizations, the burden of cancer in the United States remains high. As public health organizations, particularly county, state, tribal, and territorial health departments, try to reduce the significant burden of cancer, they face additional issues that make it difficult to address cancer in a comprehensive way. These challenges along with the need to accelerate progress in reducing the U.S. cancer burden, prompted the Centers for Disease Control and Prevention (CDC) and its national partners to begin to work together to further define and describe comprehensive cancer control (CCC) as an approach to reducing the burden of cancer. CCC is defined as "an integrated and coordinated approach to reducing cancer incidence, morbidity, and mortality through prevention, early detection, treatment, rehabilitation, and palliation." This article describes the national effort to support comprehensive cancer control, outlines national and state level success in comprehensive cancer control, and provides a call to action to public, private, and non-profit organizations, governments of all levels, and individuals to renew their commitments to reducing the burden of cancer. 相似文献
996.
Lovastatin-induced apoptosis in human melanoma cell lines 总被引:7,自引:0,他引:7
Shellman YG Ribble D Miller L Gendall J Vanbuskirk K Kelly D Norris DA Dellavalle RP 《Melanoma research》2005,15(2):83-89
The cholesterol-lowering medications, statins, inhibit cellular proliferation and induce apoptosis in an array of cancer cell lines, including melanoma. We investigated the apoptotic mechanism of lovastatin on human melanoma cell lines in vitro. The cytotoxicity of statins on multiple cell lines was examined by Cell Titer 96 Aqueous One solution cell proliferation assay (MTS assay). Apoptosis was assayed by ethidium bromide and acridine orange morphologic assays, an Annexin V apoptosis detection kit and active caspase 3 assays. Farnesyl pyrophosphate and geranylgeranyl pyrophosphate add-back experiments were performed to better define the molecular mechanisms mediating lovastatin cytotoxicity. Lovastatin caused cytotoxicity in human and murine melanoma cells, but did not induce toxicity in an epidermoid carcinoma cell line A431. For human melanoma cells, lovastatin precipitated cell rounding, increased the percentage of apoptotic cells detected by ethidium bromide and acridine orange staining and by the Annexin V apoptosis detection kit, and resulted in a 50-fold increase in active caspase 3, corroborating that lovastatin induced apoptosis. Adding back geranylgeranyl pyrophosphate, but not farnesyl pyrophosphate, reversed the effects of lovastatin in A375 cells. Of the five statins tested, pravastatin was least effective in killing melanoma cells. Lovastatin induced caspase-dependent apoptosis in multiple melanoma cell lines via a geranylation-specific mechanism. This study supports a possible role of lovastatin as a therapeutic, adjuvant or chemopreventive agent for melanoma. 相似文献
997.
Hyperbaric oxygen for carbon monoxide poisoning : a systematic review and critical analysis of the evidence 总被引:2,自引:0,他引:2
Poisoning with carbon monoxide (CO) is an important cause of unintentional and intentional injury worldwide. Hyperbaric oxygen (HBO) enhances CO elimination and has been postulated to reduce the incidence of neurological sequelae. These observations have led some clinicians to use HBO for selected patients with CO poisoning, although there is considerable variability in clinical practice. This article assesses the effectiveness of HBO compared with normobaric oxygen (NBO) for the prevention of neurological sequelae in patients with acute CO poisoning. The following databases were searched: MEDLINE (1966 to present), EMBASE (1980 to present), and the Controlled Trials Register of the Cochrane Collaboration, supplemented by a manual review of bibliographies of identified articles and discussion with recognised content experts. All randomised controlled trials involving people acutely poisoned with CO, regardless of severity, were examined. The primary analysis included all trials from which data could be extracted. Sensitivity analysis examined trials with better validity (defined using the validated instrument of Jadad) and those enrolling more severely poisoned patients. Two reviewers independently extracted from each trial, including information on the number of randomised patients, types of participants, the dose and duration of the intervention, and the prevalence of neurological sequelae at follow-up. A pooled odds ratio (OR) for the presence of neurological symptoms at 1-month follow-up was calculated using a random effects model. Bayesian models were also investigated to illustrate the degree of certainty about clinical effectiveness. Eight randomised controlled trials were identified. Two had no evaluable data and were excluded. The remaining trials were of varying quality and two have been published only as abstracts. The severity of CO poisoning varied among trials. At 1-month follow-up after treatment, sequelae possibly related to CO poisoning were present in 242 of 761 patients (36.1%) treated with NBO, compared with 259 of 718 patients (31.8%) treated with HBO. Restricting the analysis to the trials with the highest quality scores or those that enrolled all patients regardless of severity did not change the lack of statistical significance in the outcome of the pooled analysis. We found empiric evidence of multiple biases that operated to inflate the benefit of HBO in two positive trials. In contrast, the interpretation of negative trials was hampered by low rates of follow-up, unusual interventions for control patients and inclusion of less severely poisoned patients. Collectively, these limitations may have led negative trials to overlook a real and substantial benefit of HBO (type II error). There is conflicting evidence regarding the efficacy of HBO treatment for patients with CO poisoning. Methodological shortcomings are evident in all published trials, with empiric evidence of bias in some, particularly those that suggest a benefit of HBO. Bayesian analysis further illustrates the uncertainty about a meaningful clinical benefit. Consequently, firm guidelines regarding the use of HBO for patients with CO poisoning cannot be established. Further research is needed to better define the role of HBO, if any, in the treatment of CO poisoning. Such research should not exclude patients with severe poisoning, have a primary outcome that is clinically meaningful and have oversight from an independent data monitoring and ethics committee. 相似文献
998.
Buckley PF 《Expert opinion on pharmacotherapy》2005,6(12):2077-2089
The purpose of this review is to critically review the current literature on olanzapine with an emphasis on emergent themes and key findings in the use of this agent for the treatment of mood disorders and schizophrenia. New information continues to emerge on the impact of olanzapine on schizophrenia and on aspects of the course of mood disorders. There are also continued efforts to understand, predict and manage the side-effect risk with olanzapine. 相似文献
999.
Reimschuessel R Stewart L Squibb E Hirokawa K Brady T Brooks D Shaikh B Hodsdon C 《The AAPS journal》2005,7(2):E288-E327
Information about drug residues and pharmacokinetic parameters in aquatic species is relatively sparse. In addition, it is difficult to rapidly compare data between studies due to differences in experimental conditions, such as water temperatures and salinity. To facilitate the study of aquatic species drug metabolism, we constructed a Fish Drug/Chemical Analysis Phish-Pharm (FDA-PP) database. This database consists of more than 400 articles that include data from 90 species (64 genera) of fish. Data fields include genus, species, water temperatures, the average animal weight, sample types analyzed, drug (or chemical) name, dosage, route of administration, metabolites identified, method of analysis, protein binding, clearance, volume of distribution in a central compartment (Vc) or volume of distribution at steady-state (Vd), and drug half-lives (t((1/2))). Additional fields list the citation, authors, title, and Internet links. The document will be periodically updated, and users are invited to submit additional data. Updates will be announced in future issues of The AAPS Journal. This database will be a valuable resource to investigators of drug metabolism in aquatic species as well as government and private organizations involved in the drug approval process for aquatic species. 相似文献
1000.
Torok H Taylor S Baumann L Jones T Wieder J Lowe N Jarret M Rich P Pariser D Tschen E Martin D Menter A Weiss J 《Journal of drugs in dermatology : JDD》2005,4(5):592-597
This was a 12-month extension of a randomized, investigator-blinded, multicenter, 8-week trial with triple combination (TC) cream in facial melasma. A total of 585 patients were enrolled in the study and 569 patients received study medication. Three hundred eighty-nine patients completed 6 months of treatment and 327 patients completed 12 months of treatment. TC cream demonstrated a favorable safety profile: only 14 patients (2.5%) discontinued the study due to treatment-related adverse events (AEs). The 2 cases of skin atrophy were mild and did not lead to withdrawal. From the 23 cases of mild telangiectasia, only 2 resulted in discontinuation. All others were transient. Results confirmed those of a previous smaller study, with both physicians and patients reporting clinically significant improvements in melasma. By month 12, 80% of patients had lesions completely cleared or nearly cleared. Once daily application of TC cream applied intermittently over a long period is a safe, tolerable, and effective treatment for moderate to severe melasma of the face. 相似文献