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Dive into the research topics where Edward M. Schaeffer is active.

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Featured researches published by Edward M. Schaeffer.


Nature | 2000

PKC-θ is required for TCR-induced NF-κB activation in mature but not immature T lymphocytes

Zuoming Sun; Christopher Arendt; Wilfried Ellmeier; Edward M. Schaeffer; Mary Jean Sunshine; Leena Gandhi; Justin P. Annes; Daniela Petrzilka; Abraham Kupfer; Pamela L. Schwartzberg; Dan R. Littman

Productive interaction of a T lymphocyte with an antigen-presenting cell results in the clustering of the T-cell antigen receptor (TCR) and the recruitment of a large signalling complex to the site of cell–cell contact. Subsequent signal transduction resulting in cytokine gene expression requires the activation of one or more of the multiple isoenzymes of serine/threonine-specific protein kinase C (PKC). Among the several PKC isoenzymes expressed in T cells, PKC-θ is unique in being rapidly recruited to the site of TCR clustering. Here we show that PKC-θ is essential for TCR-mediated T-cell activation, but is dispensable during TCR-dependent thymocyte development. TCR-initiated NF-κB activation was absent from PKC-θ-/- mature T lymphocytes, but was intact in thymocytes. Activation of NF-κB by tumour-necrosis factor α and interleukin-1 was unaffected in the mutant mice. Although studies in T-cell lines had suggested that PKC-θ regulates activation of the JNK signalling pathway, induction of JNK was normal in T cells from mutant mice. These results indicate that PKC-θ functions in a unique pathway that links the TCR signalling complex to the activation of NF-κB in mature T lymphocytes.


The Journal of Urology | 2011

Complications After Prostate Biopsy: Data From SEER-Medicare

Stacy Loeb; H. Ballentine Carter; Sonja I. Berndt; Winnie Ricker; Edward M. Schaeffer

PURPOSE More than 1 million prostate biopsies are performed annually among Medicare beneficiaries. We determined the risk of serious complications requiring hospitalization. We hypothesized that with emerging multidrug resistant organisms there may be an increasing risk of infectious complications. MATERIALS AND METHODS In a 5% random sample of Medicare participants in SEER (Surveillance, Epidemiology and End Results) regions from 1991 to 2007 we compared 30-day hospitalization rates and ICD-9 primary diagnosis codes for admissions between 17,472 men who underwent prostate biopsy and a random sample of 134,977 controls. Multivariate logistic and Poisson regression were used to examine the risk and predictors of serious infectious and noninfectious complications with time. RESULTS The 30-day hospitalization rate was 6.9% within 30 days of prostate biopsy, which was substantially higher than the 2.7% in the control population. After adjusting for age, race, SEER region, year and comorbidities prostate biopsy was associated with a 2.65-fold (95% CI 2.47-2.84) increased risk of hospitalization within 30 days compared to the control population (p <0.0001). The risk of infectious complications requiring hospitalization after biopsy was significantly greater in more recent years (p(trend) = 0.001). Among men undergoing biopsy, later year, nonwhite race and higher comorbidity scores were significantly associated with an increased risk of infectious complications. CONCLUSIONS The risk of hospitalization within 30 days of prostate biopsy was significantly higher than in a control population. Infectious complications after prostate biopsy have increased in recent years while the rate of serious noninfectious complications is relatively stable. Careful patient selection for prostate biopsy is essential to minimize the potential harms.


Nature Immunology | 2001

Mutation of Tec family kinases alters T helper cell differentiation.

Edward M. Schaeffer; George S. Yap; Carol Lewis; Michael J. Czar; Daniel W. McVicar; Allen W. Cheever; Alan Sher; Pamela L. Schwartzberg

The Tec kinases Rlk and Itk are critical for full T cell receptor (TCR)-induced activation of phospholipase C-γ and mitogen-activated protein kinase. We show here that the mutation of Rlk and Itk impaired activation of the transcription factors NFAT and AP-1 and production of both T helper type 1 (TH1) and TH2 cytokines. Consistent with these biochemical defects, Itk−/− mice did not generate effective TH2 responses when challenged with Schistosoma mansoni eggs. Paradoxically, the more severely impaired Rlk−/−Itk−/− mice were able to mount a TH2 response and produced TH2 cytokines in response to this challenge. In addition, Rlk−/−Itk−/− cells showed impaired TCR-induced repression of the TH2-inducing transcription factor GATA-3, suggesting a potential mechanism for TH2 development in these hyporesponsive cells. Thus, mutations that affect Tec kinases lead to complex alterations in CD4+ TH cell differentiation.


European Urology | 2012

A Critical Analysis of the Long-Term Impact of Radical Prostatectomy on Cancer Control and Function Outcomes

Stephen A. Boorjian; James A. Eastham; Markus Graefen; Bertrand Guillonneau; R. Jeffrey Karnes; Judd W. Moul; Edward M. Schaeffer; Christian G. Stief; Kevin C. Zorn

CONTEXT The optimal management strategy for men with newly diagnosed clinically localized prostate cancer remains a matter of debate. Numerous series have reported cancer control and quality-of-life (QoL) outcomes following treatment with radical prostatectomy (RP). OBJECTIVE Critically review published oncologic and functional outcomes after RP, and evaluate factors associated with these outcome measures. EVIDENCE ACQUISITION A review of the literature was performed using the Medline and Web of Sciences databases. Relevant reports published between 1980 and 2011 identified using the keywords prostate cancer, radical prostatectomy, prostate-specific antigen, biochemical recurrence, incontinence, and erectile dysfunction were reviewed and summarized. EVIDENCE SYNTHESIS Cancer control rates following RP largely depend on the definition of treatment efficacy. While up to 40% of men have been reported to experience postoperative biochemical recurrence on long-term follow-up, death from prostate cancer has been noted in <10% of men at 15 yr after surgery in contemporary series. For men with high-risk disease, surgery affords pathologic staging, thereby facilitating the selective application of secondary therapies, and has been associated with decreased mortality risk versus radiation in retrospective series. Reported functional outcomes after surgery, particularly urinary continence and erectile dysfunction, have varied greatly to date. These assessments have been limited by nonstandardized reporting methodology. The use of robot-assisted radical prostatectomy has increased in recent years, and while follow-up is thus far short, available data do not suggest the superiority of either approach in terms of functional or oncologic outcomes. CONCLUSIONS RP is associated with excellent long-term cancer control. Continued efforts to conduct prospective assessments of postoperative functional outcomes are necessary using validated QoL instruments. The importance of surgical approach will also require further study, incorporating comparative oncologic, functional, and economic data.


Oncogene | 2008

Androgen-induced programs for prostate epithelial growth and invasion arise in embryogenesis and are reactivated in cancer

Edward M. Schaeffer; Luigi Marchionni; Zhenhua Huang; Brian W. Simons; A. Blackman; Wayne Yu; Giovanni Parmigiani; David M. Berman

Cancer cells differentiate along specific lineages that largely determine their clinical and biologic behavior. Distinct cancer phenotypes from different cells and organs likely result from unique gene expression repertoires established in the embryo and maintained after malignant transformation. We used comprehensive gene expression analysis to examine this concept in the prostate, an organ with a tractable developmental program and a high propensity for cancer. We focused on gene expression in the murine prostate rudiment at three time points during the first 48 h of exposure to androgen, which initiates proliferation and invasion of prostate epithelial buds into surrounding urogenital sinus mesenchyme. Here, we show that androgen exposure regulates genes previously implicated in prostate carcinogenesis comprising pathways for the phosphatase and tensin homolog (PTEN), fibroblast growth factor (FGF)/mitogen-activated protein kinase (MAPK), and Wnt signaling along with cellular programs regulating such ‘hallmarks’ of cancer as angiogenesis, apoptosis, migration and proliferation. We found statistically significant evidence for novel androgen-induced gene regulation events that establish and/or maintain prostate cell fate. These include modulation of gene expression through microRNAs, expression of specific transcription factors, and regulation of their predicted targets. By querying public gene expression databases from other tissues, we found that rather than generally characterizing androgen exposure or epithelial budding, the early prostate development program more closely resembles the program for human prostate cancer. Most importantly, early androgen-regulated genes and functional themes associated with prostate development were highly enriched in contrasts between increasingly lethal forms of prostate cancer, confirming a ‘reactivation’ of embryonic pathways for proliferation and invasion in prostate cancer progression. Among the genes with the most significant links to the development and cancer, we highlight coordinate induction of the transcription factor Sox9 and suppression of the proapoptotic phospholipid-binding protein Annexin A1 that link early prostate development to early prostate carcinogenesis. These results credential early prostate development as a reliable and valid model system for the investigation of genes and pathways that drive prostate cancer.


Behavioural Pharmacology | 1997

Drugs acting upon the cyclic adenosine monophosphate/protein kinase A signalling pathway modulate memory consolidation when given late after training into rat hippocampus but not amygdala.

Lia R. M. Bevilaqua; Patricia Ardenghi; Nadja Schröder; Elke Bromberg; Paulo Sergio Kroeff Schmitz; Edward M. Schaeffer; João Quevedo; M. Bianchin; Roger Walz; Jorge H. Medina; Ivan Izquierdo

Rats implanted bilaterally with cannulae in the CA1 region of the dorsal hippocampus or in the amygdala were trained in one-trial step-down inhibitory (passive) avoidance using a 0.4 mA footshock. At various times after training (0,1.5,3,6 or 9 h for animals implanted in the hippocampus; 0 or 3 h for those implanted in the amygdala), they received infusions of 8-Br-cAMP (cyclic adenosine monophosphate) (1.25 μg/side), SKF38393 (7.5 μg/side), SCH23390 (0.5 μg/side), norepinephrine C1H (0.3 μg/side), timolol C1H (0.3 μg/side), 8-HO-DPAT (2.5 μg/side), NAN-190 (2.5 μg/side), forskolin (0.5 μg/side) or KT5720 (0.5 μg/side). Rats were tested for retention 24 h after training. SKF38393 is an agonist and SCH23390 an antagonist at dopamine D1 receptors, timolol is a β-adrenoceptor antagonist, 8-HO-DPAT is an agonist and NAN-190 an antagonist at 5HT1A receptors, forskolin enhances adenylyl cyclase, and KT5720 inhibits protein kinase A. When given into the hippocampus 0 h post-training, norepinephrine enhanced memory and KT5720 was amnestic. When given 1.5 h after training, all treatments were ineffective. When given 3 or 6 h post-training, 8-Br-cAMP, forskolin, SKF 38393, noradrenaline and NAN-190 caused memory facilitation, and KT5720, SCH23390, timolol and 8-HO-DPAT caused retrograde amnesia. At 9 h from training, all treatments were again ineffective. When given into the amygdala 0 or 3 h post-training all treatments were ineffective, except for noradrenaline at 0 h, which caused retrograde facilitation. The data agree with the suggestion that in the hippocampus, but not the amygdala, a cAMP/protein kinase A pathway is involved in memory consolidation at 3 and 6 h from training, and that this is regulated by D1, β, and 5HT1A receptors. This correlates with a previous report of increased cAMP levels, protein kinase A activity and P-CREB levels at 3-6 h from training in rat hippocampus in this task. This may be taken to suggest that the hippocampus, but not the amygdala, is involved in the long-term storage of step-down inhibitory avoidance in the rat.


Current Opinion in Immunology | 2000

Tec family kinases in lymphocyte signaling and function

Edward M. Schaeffer; Pamela L. Schwartzberg

The Tec kinases are required for full Ca(2+) mobilization in lymphocytes. Recent data suggest that this process occurs via a multiprotein complex that includes LAT and SLP-76 in T cells and BLNK/SLP-65 in B cells. Mutational analyses have revealed critical roles for Tec kinases in lymphocyte development and function.


The Journal of Urology | 2008

High anterior release of the levator fascia improves sexual function following open radical retropubic prostatectomy.

Matthew E. Nielsen; Edward M. Schaeffer; Penny Marschke; Patrick C. Walsh

PURPOSE Recent anatomical studies have shown that branches of the cavernous nerves running adjacent to the prostate at the apex travel more anteriorly than previously recognized. Outcomes of robot assisted radical prostatectomy suggest improved postoperative sexual outcomes following high anterior release of the levator fascia. We prospectively evaluated the effect of high anterior release on oncological and sexual function outcomes following open radical retropubic prostatectomy. MATERIALS AND METHODS A total of 167 patients with clinically localized prostate cancer with a preoperative Sexual Health Inventory for Men score of greater than 21 underwent radical retropubic prostatectomy with bilateral nerve sparing and selective high anterior release, as performed by a single surgeon. Data on postoperative sexual function were collected by an independent third party. Sexual function outcomes at 12 months were defined as 1) a Sexual Health Inventory for Men score of 16 or greater and/or a satisfaction score of 4 or greater and 2) a Sexual Health Inventory for Men score of 22 or greater. RESULTS Because unilateral high anterior release was equivalent to bilateral high anterior release for both definitions (p >0.3), they were combined into 1 group for analyses. Patients undergoing high anterior release were more likely to achieve a Sexual Health Inventory for Men score of 16 or greater and/or a satisfaction score of 4 (93% vs 77%, p = 0.007), and a Sexual Health Inventory for Men score of 22 or greater (70% vs 54%, p = 0.07) at 1 year. Return to baseline (a Sexual Health Inventory for Men score of 22 or greater) was even higher among patients receiving high anterior release who were more sexually active (greater than 1 attempt per week) preoperatively (78% vs 52%, p <0.05). The improved outcomes in potency achieved with high anterior release did not increase the likelihood of a positive surgical margin. CONCLUSIONS Unilateral or bilateral high anterior release of the levator fascia in open radical retropubic prostatectomy provides excellent oncological results and is associated with improved postoperative sexual function.


The Journal of Urology | 2008

Prostate Specific Antigen Testing Among the Elderly—When To Stop?

Edward M. Schaeffer; H. Ballentine Carter; Anna Kettermann; Stacy Loeb; Luigi Ferrucci; Patricia Landis; Bruce J. Trock; E. Jeffrey Metter

PURPOSE Prostate specific antigen testing is common in the elderly despite evidence that older men without aggressive prostate cancer are unlikely to benefit from diagnosis and treatment. We evaluated the relationship between prostate specific antigen and the risk of aggressive prostate cancer developing in men of various ages. MATERIALS AND METHODS This longitudinal cohort study consisted of 849 men (122 with and 727 without prostate cancer) with serial prostate specific antigen measurements participating in the Baltimore Longitudinal Study of Aging. The primary outcome measure was the proportion of men by prostate specific antigen and age who died of prostate cancer or in whom aggressive prostate cancer developed (death from prostate cancer, a prostate specific antigen 20 ng/ml or greater, or Gleason score 8 or greater). RESULTS No participants between 75 and 80 years old with a prostate specific antigen less than 3.0 ng/ml died of prostate cancer. In contrast, men of all ages with a prostate specific antigen of 3.0 ng/ml or greater had a continually increasing probability of death from prostate cancer (Fishers exact test p <0.001). The time to death or diagnosis of aggressive prostate cancer after age 75 years was not significantly different between the prostate specific antigen categories of 3 to 3.9 and 4 to 9.9 ng/ml (p = 0.634), whereas the time to death or diagnosis of high risk prostate cancer was significantly longer for the prostate specific antigen category of less than 3 vs 3 ng/ml or greater (p = 0.019). CONCLUSIONS Men 75 to 80 years old with a prostate specific antigen less than 3 ng/ml are unlikely to die of or experience aggressive prostate cancer during their remaining life, suggesting that prostate specific antigen testing might be safely discontinued for these men.


The Prostate | 2011

Gene expression pathways of high grade localized prostate cancer.

Ashley E. Ross; Luigi Marchionni; Milena Vuica-Ross; Chris Cheadle; Jinshui Fan; David M. Berman; Edward M. Schaeffer

Despite advances in screening and local therapy, prostate cancer remains the second most common cause of cancer related death among American men, with those having high grade disease being at highest risk for prostate cancer mortality. Here we identify the genes and cellular pathways that distinguish high grade from low grade pathologically localized prostate cancer.

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Ashley E. Ross

Johns Hopkins University

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Phillip M. Pierorazio

Johns Hopkins University School of Medicine

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Christian P. Pavlovich

Johns Hopkins University School of Medicine

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Jonathan I. Epstein

Johns Hopkins University School of Medicine

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Alan W. Partin

Johns Hopkins University

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Misop Han

Johns Hopkins University

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Mohamad E. Allaf

Johns Hopkins University School of Medicine

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