43 research outputs found

    Eukaryotic Protein Kinases (ePKs) of the Helminth Parasite Schistosoma mansoni

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    <p>Abstract</p> <p>Background</p> <p>Schistosomiasis remains an important parasitic disease and a major economic problem in many countries. The <it>Schistosoma mansoni </it>genome and predicted proteome sequences were recently published providing the opportunity to identify new drug candidates. Eukaryotic protein kinases (ePKs) play a central role in mediating signal transduction through complex networks and are considered druggable targets from the medical and chemical viewpoints. Our work aimed at analyzing the <it>S. mansoni </it>predicted proteome in order to identify and classify all ePKs of this parasite through combined computational approaches. Functional annotation was performed mainly to yield insights into the parasite signaling processes relevant to its complex lifestyle and to select some ePKs as potential drug targets.</p> <p>Results</p> <p>We have identified 252 ePKs, which corresponds to 1.9% of the <it>S. mansoni </it>predicted proteome, through sequence similarity searches using HMMs (Hidden Markov Models). Amino acid sequences corresponding to the conserved catalytic domain of ePKs were aligned by MAFFT and further used in distance-based phylogenetic analysis as implemented in PHYLIP. Our analysis also included the ePK homologs from six other eukaryotes. The results show that <it>S. mansoni </it>has proteins in all ePK groups. Most of them are clearly clustered with known ePKs in other eukaryotes according to the phylogenetic analysis. None of the ePKs are exclusively found in <it>S. mansoni </it>or belong to an expanded family in this parasite. Only 16 <it>S. mansoni </it>ePKs were experimentally studied, 12 proteins are predicted to be catalytically inactive and approximately 2% of the parasite ePKs remain unclassified. Some proteins were mentioned as good target for drug development since they have a predicted essential function for the parasite.</p> <p>Conclusions</p> <p>Our approach has improved the functional annotation of 40% of <it>S. mansoni </it>ePKs through combined similarity and phylogenetic-based approaches. As we continue this work, we will highlight the biochemical and physiological adaptations of <it>S. mansoni </it>in response to diverse environments during the parasite development, vector interaction, and host infection.</p

    Patterns of Declining Use and the Adverse Effect of Primary Androgen Deprivation on All-cause Mortality in Elderly Men with Prostate Cancer.

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    BACKGROUND: Primary androgen deprivation therapy (pADT) is commonly used to treat elderly men diagnosed with localized prostate cancer (CaP), despite the lack of evidence supporting its use. OBJECTIVE: To examine the effect of pADT on mortality and to assess contemporary trends of pADT use in elderly men with CaP. DESIGN, SETTING, AND PARTICIPANTS: Men older than 65 yr residing in Surveillance, Epidemiology, and End Results (SEER) registry areas diagnosed with localized or locally advanced CaP between 1992 and 2009 and not receiving definitive therapy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Propensity score (PS)-weighted Cox proportional hazards models were used to estimate the effect of pADT use on overall survival among patients receiving pADT. The interaction between comorbidity-adjusted life expectancy (LE) and pADT use was assessed within the Cox and PS-weighted models. Contemporary (2004-2009) trends for pADT use were analyzed by linear regression. RESULTS AND LIMITATIONS: The primary cohort included 46 376 men, of whom 17 873 received pADT (39%). Patients with \u3e10 yr LE had lower pADT utilization rates than patients with short LE. Between 2004 and 2009, the use of pADT in men with localized CaP decreased by 14% (from 36% to 22%). Relative to observation, pADT was associated with a survival disadvantage, with a hazard ratio for all-cause mortality of 1.37 (95% confidence interval 1.20-1.56). Limitations included biases not accounted for by the PS-weighted model, changes in CaP staging over the study period, the absence of prostate-specific antigen (PSA) data prior to 2004, and the limits of retrospective analysis to demonstrate causality. CONCLUSIONS: The use of pADT in elderly men with localized CaP has decreased over time. For men forgoing primary definitive therapy, the use of pADT is not associated with a survival benefit compared to observation, and denies men an opportunity for cure with definitive therapy. The deleterious effect of pADT is most pronounced in men with prolonged LE. PATIENT SUMMARY: In this report, we assessed the effect of primary androgen deprivation (pADT) on prostate cancer mortality and determined current trends in the use of pADT. We showed that use of pADT in men aged \u3e65 yr with localized prostate cancer has decreased over time. We also found that pADT is detrimental to men with localized prostate cancer, and particularly men with longer life expectancy. Therefore, we conclude that ADT should not be used as a primary treatment for men with prostate cancer that has not spread beyond the prostate
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