I A Sesterhenn

Rajiv Gandhi Cancer Institute & Research Centre, New Dilli, NCT, India

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Publications (244)885.46 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Biomarkers that are validated in independent cohorts are needed to improve risk assessment for prostate cancer (PCa). A racially diverse cohort of men (20% African American [AA]) was used to evaluate the association of the clinically validated 17-gene Genomic Prostate Score (GPS) with recurrence after radical prostatectomy and adverse pathology (AP) at surgery. Biopsies from 431 men treated for National Comprehensive Cancer Network (NCCN) very low-, low-, or intermediate-risk PCa between 1990 and 2011 at two US military medical centers were tested to validate the association between GPS and biochemical recurrence (BCR) and to confirm the association with AP. Metastatic recurrence (MR) was also evaluated. Cox proportional hazards models were used for BCR and MR, and logistic regression was used for AP. Central pathology review was performed by one uropathologist. AP was defined as primary Gleason pattern 4 or any pattern 5 and/or pT3 disease. GPS results (scale: 0-100) were obtained in 402 cases (93%); 62 men (15%) experienced BCR, 5 developed metastases, and 163 had AP. Median follow-up was 5.2 yr. GPS predicted time to BCR in univariable analysis (hazard ratio per 20 GPS units [HR/20 units]: 2.9; p<0.001) and after adjusting for NCCN risk group (HR/20 units: 2.7; p<0.001). GPS also predicted time to metastases (HR/20 units: 3.8; p=0.032), although the event rate was low (n=5). GPS was strongly associated with AP (odds ratio per 20 GPS units: 3.3; p<0.001), adjusted for NCCN risk group. In AA and Caucasian men, the median GPS was 30.3 for both, the distributions of GPS results were similar, and GPS was similarly predictive of outcome. The association of GPS with near- and long-term clinical end points establishes the assay as a strong independent measure of PCa aggressiveness. Tumor aggressiveness, as measured by GPS, and outcomes were similar in AA and Caucasian men in this equal-access health care system. Predicting outcomes in men with newly diagnosed prostate cancer is challenging. This study demonstrates that a new molecular test, the Genomic Prostate Score, which can be performed on a patient's original prostate needle biopsy, can predict the aggressiveness of the cancer and help men make decisions regarding the need for immediate treatment of their cancer. Copyright © 2014 European Association of Urology. Published by Elsevier B.V. All rights reserved.
    European Urology 11/2014; · 12.48 Impact Factor
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    ABSTRACT: Erythroblast transformation-specific-related gene (ERG) fusions, the most common and validated prostate cancer (CaP) genome alteration, result in alterations in the expression of the ERG oncoprotein. Significantly lower frequencies of ERG have been reported in tumors of African American (AA) in comparison to Caucasian American (CA) men. Building on our preliminary observations, this study has focused on the increased association of the ERG-negative status with higher-grade prostate tumors in AA men. Representative whole-mount prostate sections from a matched cohort of 63 AA and 63 CA men with Gleason scores of 4+3 and those with Gleason scores of 8-10 were analyzed for ERG oncoprotein by immunohistochemistry. The striking finding of this study was that ERG expression was 3 times more likely to be present in the higher-grade index tumors of CA men compared to AA men (31 of 63 vs. 10 of 63 patients, respectively; P<0.0001). Although the mechanisms underlying these differences have not been elucidated, the present study along with our previous observations underscores that ERG typing may enhance the understanding of ethnic differences and future targeted therapy of CaP.
    Molecular and Clinical Oncology 11/2014; 2(6):982-986.
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    ABSTRACT: Overexpression of ERG in the prostate epithelium, due to chromosomal translocations, contributes to prostate tumorigenesis. Here, genomic analysis of ERG siRNA-treated prostate cells harboring the endogenous TMPRSS2-ERG fusion revealed an inverse relationship between ERG and Annexin A2 (ANXA2) expression at both the RNA and protein level. ANXA2, a Ca2+-dependent and phospholipid-binding protein, is involved in various cellular functions, including maintenance of epithelial cell polarity. Mechanistic studies defined the prostate-specific transcription start site of ANXA2 and showed that the recruitment of ERG to the ANXA2 promoter is required for transcriptional repression by ERG. Knockdown of ERG enhanced the apical localization of ANXA2, the bundling of actin filaments at cell-cell junctions and formation of a polarized epithelial phenotype. ERG overexpression disrupted ANXA2 mediated cell polarity and promoted epithelial mesenchymal transition (EMT) by inhibiting CDC42 and RHOA, and by activating cofilin. Immunohistochemistry (IHC), demonstrated a reciprocal relationship of ANXA2 and ERG expression in a large fraction of primary prostate cancer clinical specimens. ANXA2 was absent or markedly reduced in ERG(+) tumors, which were mostly well-differentiated. ERG(-) tumors, meanwhile, expressed moderate to high levels of ANXA2, and were either poorly-differentiated or displayed subsets of poorly-differentiated cells. Taken together, the transcriptional repression of ANXA2 by ERG in prostate epithelial cells plays a critical role in abrogating differentiation, promoting EMT, and in the reciprocal correlation of ERG and ANXA2 expression observed in human prostate cancer. Implications: ANXA2 is a new component of the ERG network with potential to enhance biological stratification and therapeutic targeting of ERG stratified prostate cancers.
    Molecular Cancer Research 10/2014; · 4.50 Impact Factor
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    ABSTRACT: Overexpression of the erythroblast transformation‑specific‑related gene (ERG) oncoprotein due to transmembrane protease, serine 2 (TMPRSS2)‑ERG fusion, the most prevalent genomic alteration in prostate cancer (CaP), is more frequently observed among Caucasian patients compared to patients of African or Asian descent. To the best of our knowledge, this is the first study to investigate the prevalence of ERG alterations in a multiethnic cohort of CaP patients. A total of 191 formalin‑fixed paraffin‑embedded sections of transrectal ultrasound‑guided prostate biopsy specimens, collected from 120 patients treated at the Sime Darby Medical Centre, Subang Jaya, Malaysia, were analyzed for ERG protein expression by immunohistochemistry using the anti‑ERG monoclonal antibody 9FY as a surrogate for the detection of ERG fusion events. The overall frequency of ERG protein expression in the population evaluated in this study was 39.2%. Although seemingly similar to rates reported in other Asian communities, the expression of ERG was distinct amongst different ethnic groups (p=0.004). Malaysian Indian (MI) patients exhibited exceedingly high expression of ERG in their tumors, almost doubling that of Malaysian Chinese (MC) patients, whereas ERG expression was very low amongst Malay patients (12.5%). When collectively analyzing data, we observed a significant correlation between younger patients and higher ERG expression (p=0.04). The prevalence of ERG expression was significantly different amongst CaP patients of different ethnicities. The higher number of ERG‑expressing tumors among MI patients suggested that the TMPRSS2‑ERG fusion may be particularly important in the pathogenesis of CaP amongst this group of patients. Furthermore, the more frequent expression of ERG among the younger patients analyzed suggested an involvement of ERG in the early onset of CaP. The results of this study underline the value of using ERG status to better understand the differences in the etiology of CaP initiation and progression between ethnic groups.
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    ABSTRACT: The fusion between ERG coding sequences and the TMPRSS2 promoter is the most prevalent in prostate cancer (CaP). The presence of two main types of TMPRSS2-ERG fusion transcripts in CaP specimens, Type I and Type II, prompted us to hypothesize that the cumulative actions of different ERG variants may impact CaP development/progression. Using TMPRSS2-ERG3 (Type I) and TMPRSS2-ERG8 (Type II) expression vectors, we determined that the TMPRSS2- ERG8 encoded protein is deficient in transcriptional regulation compared to TMPRSS2-ERG3. Co-transfection of vectors resulted in decreased transcriptional regulation compared to TMPRSS2-ERG3 alone, suggesting transdominance of ERG8. Expression of exogenous ERG8 protein resulted in a decrease in endogenous ERG3 protein levels in TMPRSS2-ERG positive VCaP cells, with a concomitant decrease in C-MYC. Further, we showed a physical association between ERG3 and ERG8 in live cells by the bimolecular fluorescence complementation assay, providing a basis for the observed effects. Inhibitory effects of TMPRSS2-ERG8 on TMPRSS2- ERG3 were also corroborated by gene expression data from human prostate cancers, which showed a positive correlation between C-MYC expression and TMPRSS2-ERG3/TMPRSS2- ERG8 ratio. We propose that an elevated TMPRSS2-ERG3/TMPRSS2-ERG8 ratio results in elevated C-MYC in CaP, providing a strong rationale for the biomarker and therapeutic utility of ERG splice variants, along with C-MYC.
    Genes & cancer. 07/2014; 5(7-8):273-84.
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    ABSTRACT: Filipinos with prostate cancer (CaP) are at increased risk of harboring advanced stages and lower survival rates compared to other Asians. This study aims to investigate prevalence of ETS-related gene (ERG) oncoprotein overexpression in Filipinos as surrogate of TMPRSS2-ERG gene fusions, using a highly specific monoclonal antibody (ERG-MAb), and conduct the first attempt to study the role of genetic alterations in the aggressive tumor biologic behaviour of CaP among Filipinos.
    The Prostate 06/2014; · 3.57 Impact Factor
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    ABSTRACT: The prostate transmembrane protein androgen induced 1 (PMEPA1) gene is highly expressed in prostate epithelial cells and is a direct transcriptional target for the androgen receptor (AR). AR protein levels are controlled by the AR-PMEPA1 negative feedback loop through NEDD4-E3 ligase. Reduced expression of PMEPA1 observed in prostate tumors, suggests that loss of PMEPA1 may play critical roles in prostate tumorigenesis. This study focuses on epigenetic mechanisms of reduced PMEPA1 expression in the cancer of the prostate (CaP). Benign (n = 77) and matched malignant (n = 77) prostate epithelial cells were laser capture micro-dissected from OCT embedded frozen prostate sections from 42 Caucasian American (CA) and 35 African American (AA) cases. Purified DNA specimens were analyzed for CpG methylation of the PMEPA1 gene. PMEPA1 mRNA expression levels were evaluated by qRT-PCR. Analysis of PMEPA1 methylation and mRNA expression in the same tumor cell populations indicated a significant inverse correlation between mRNA expression and methylation in CaP (P = 0.0115). We noted higher frequency of CpG methylation within the evaluated first intronic region of the PMEPA1 gene in prostate tumors of CA men as compared with AA. In CaP cell lines, PMEPA1 expression was induced and AR protein levels were diminished in response to treatment with the DNA methyltransferase inhibitor, 5-aza-2'-deoxycytidine (decitabine). Cell culture-based studies demonstrated that decitabine restores PMEPA1 expression in AR-positive CaP cell lines. This report reveals the potential role of PMEPA1 gene methylation in the regulation of AR stability. Thus, downregulation of PMEPA1 may result in increased AR protein levels and function in CaP cells, contributing to prostate tumorigenesis.
    Epigenetics: official journal of the DNA Methylation Society 04/2014; 9(6). · 5.11 Impact Factor
  • The Journal of Urology 04/2014; 191(4):e450. · 3.75 Impact Factor
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    ABSTRACT: Background:Approximately half of the prostate carcinomas are characterized by a chromosomal rearrangement fusing the androgen-regulated gene TMPRSS2 to the oncogenic ETS transcription factor ERG. Aim of this study was to comprehensively analyze the role and impact of the ERG rearrangement and protein expression on the progression to castration-resistant (CR) disease.Methods:We used a tissue microarray (TMA) constructed from 114 hormone naive (HN) and 117 CR PCs. We analyzed the ERG rearrangement status by fluorescence in situ hybridization and the expression profiles of ERG, androgen receptor (AR) and the proliferation marker Ki67 by immunohistochemistry.Results:Nearly half of the PC tissue specimens (HN: 38%, CR: 46%) harbored a TMPRSS2-ERG gene fusion. HN PCs with positive translocation status showed increased tumor cell proliferation (P<0.05). As expected, TMPRSS2-ERG gene fusion was strongly associated with increased ERG protein expression in HN and CR PCs (both P<0.0001). Remarkably, the study revealed a subgroup (26%) of CR PCs with ERG rearrangement but without any detectable ERG protein expression. This subgroup showed significantly lower levels of AR protein expression and androgen-regulated serum PSA (both P<0.05).Conclusions:In this study, we identified a subgroup of ERG-rearranged CR PCs without detectable ERG protein expression. Our results suggest that this subgroup could represent CR PCs with a dispensed AR pathway. These tumors might represent a thus far unrecognized subset of patients with AR-independent CR PC who may not benefit from conventional therapy directed against the AR pathway.Prostate Cancer and Prostatic Disease advance online publication, 28 January 2014; doi:10.1038/pcan.2013.62.
    Prostate cancer and prostatic diseases 01/2014; · 2.10 Impact Factor
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    ABSTRACT: Ductal adenocarcinoma of the prostate (DAC) is clinically important as its behaviour may differ from that of acinar adenocarcinoma. Our aim was to investigate the interobserver variability of this diagnosis among experts in uropathology and define diagnostic criteria. Photomicrographs of 21 carcinomas with ductal features were distributed among 20 genitourinary pathologists from 8 countries. DAC was diagnosed by 18 observers (mean 13.2 cases, range 6-19). In 11 (52%) cases a 2/3 consensus was reached for a diagnosis of DAC and in 5 (24%) there was consensus against. In DAC the respondents reported papillary architecture (86%), stratification of nuclei (82%), high-grade nuclear features (54%), tall columnar epithelium (53%), elongated nuclei (52%), cribriform architecture (40%) and necrosis (7%). The most important diagnostic feature reported for DAC was papillary architecture (59%), while nuclear and cellular features were considered most important in only 2% to 11% of cases. The most common differential diagnoses were intraductal prostate cancer (52%), high-grade PIN (37%) and acinar adenocarcinoma (17%). The most common reason for not diagnosing DAC was lack of typical architecture (33%). Papillary architecture was the most useful diagnostic feature of DAC, while nuclear and cellular features were considered less important. This article is protected by copyright. All rights reserved.
    Histopathology 01/2014; · 3.30 Impact Factor
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    ABSTRACT: Background:To determine whether prostate cancers detected in the anterior vs posterior zones impact clinicopathological features and patient outcomes. This information could potentially affect clinical management.Methods:A retrospective pathological review of 1528 radical prostatectomy specimens submitted between 1989 and 2011 was completed. Specimens were characterized as anterior zone vs posterior zone based on index tumor and predominant tumor volume location. The chi-square test was used to determine associations between tumor location and categorical patient features. Kaplan-Meier unadjusted analysis was used to compare biochemical recurrence-free and overall survival.Results:Tumors occurred predominantly in the anterior location in 155 (10.1%) of specimens. There was no difference between mean age, body mass index, racial distribution, family history, number of previous biopsies, clinical Gleason sum or pathological stage in the two groups. Fewer patients had clinically palpable disease in the anterior tumor group, 28.8% vs 40.7% (P=0.0150). Pretreatment PSA was lower in the anterior tumor group. Total tumor volume did differ with anterior tumors having a mean 8.3 cc vs 5.6 cc (P<0.0001) size and a higher incidence of positive margins (P=0.0008). There were no differences in biochemical recurrence-free or overall survival.Conclusions:Despite the potential for adverse pathological features in anterior-based disease, there appears to be no demographic predilection, notable delay in diagnosis or significant difference in survival outcomes.Prostate Cancer and Prostatic Disease advance online publication, 3 December 2013; doi:10.1038/pcan.2013.54.
    Prostate cancer and prostatic diseases 12/2013; · 2.10 Impact Factor
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    ABSTRACT: Gene fusion between TMPRSS2 promoter and the ERG proto-oncogene is a major genomic alteration found in over half of prostate cancers (CaP), which leads to aberrant androgen dependent ERG expression. Despite extensive analysis for the biological functions of ERG in CaP, there is no systematic evaluation of the ERG responsive proteome (ERP). ERP has the potential to define new biomarkers and therapeutic targets for prostate tumors stratified by ERG expression. Global proteome analysis was performed by using ERG (+) and ERG (-) CaP cells isolated by ERG immunohistochemistry defined laser capture microdissection and by using TMPRSS2-ERG positive VCaP cells treated with ERG and control siRNA. We identified 1,196 and 2,190 unique proteins stratified by ERG status from prostate tumors and VCaP cells, respectively. Comparative analysis of these two proteomes identified 330 concordantly regulated proteins characterizing enrichment of pathways modulating cytoskeletal and actin reorganization, cell migration, protein biosynthesis, and proteasome and ER-associated protein degradation. ERPs unique for ERG (+) tumors reveal enrichment for cell growth and survival pathways while proteasome and redox function pathways were enriched in ERPs unique for ERG (-) tumors. Meta-analysis of ERPs against CaP gene expression data revealed that Myosin VI and Monoamine oxidase A were positively and negatively correlated to ERG expression, respectively. This study delineates the global proteome for prostate tumors stratified by ERG expression status. The ERP data confirm the functions of ERG in inhibiting cell differentiation and activating cell growth, and identify potentially novel biomarkers and therapeutic targets. Prostate 9999: XX-XX, 2013. © 2013 Wiley Periodicals, Inc.
    The Prostate 09/2013; · 3.57 Impact Factor
  • Cancer Research 08/2013; 73(8 Supplement):1206-1206. · 9.28 Impact Factor
  • Cancer Research 05/2013; 72(4 Supplement):A27-A27. · 9.28 Impact Factor
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    ABSTRACT: ERG oncogene fusions (predominantly TMPRSS2-ERG) represent the most common (50-70% frequency) and validated prostate cancer (CaP) genome alteration in the Western countries. A common TMPRSS2-ERG fusion type leads to the androgen dependent tumor cell specific expression of the TMPRSS2-ERG fusion transcript and amino terminally truncated ERG oncoprotein. CaP prevalence and aggressiveness, as well as genomic alterations vary in different geographic locations in the world. Recent studies from our group highlighted significantly lower frequency of ERG alterations in prostate index tumors of African American men (~30%) in comparison to Caucasian Americans (~60%). Further, much lower frequencies (10 -25%) of ERG alterations have been reported in studies from China and Japan. There is no study on ERG alterations in CaP patients from India, representing a significant portion of the world male population. This study focuses on the frequency of ERG oncoprotein expression in CaP patients from India. De-identified formalin-fixed paraffin-embedded (FFPE) specimens from radical prostatectomy (RP) specimens of 51 patients from the Rajiv Gandhi Cancer Institute and Research Centre (RGCI), New Delhi, India, were analyzed for ERG alterations. The ERG oncoprotein expression as a surrogate of ERG gene fusions was analyzed by using a highly specific ERG monoclonal antibody (9FY). TMPRSS2-ERG fusion was assessed by fluorescent in situ hybridization (FISH) assays using the break-apart ERG probes. Specimens reflecting prior hormonal treatment, or lacking any tumor content, were excluded from the analyses. Of the thirty evaluable specimens, ERG positive tumors were present in 8 cases (27%) and one tumor specimen exhibited rare ERG positive cells. None of the benign glands were positive for ERG supporting previous studies showing complete specificity of the ERG oncoprotein for detection of tumors cells in prostate. Frequency of ERG oncoprotein expression is much lower in CaP patients from India in comparison to higher frequency of ERG alterations noted in Western countries. ERG frequency in Indian CaP is similar to observations from Japan and China. Since ERG oncogenic activation is a promising biomarker and therapeutic target for CaP, careful evaluation of ERG is needed in CaP patients from different parts of the world.
    Journal of Cancer. 01/2013; 4(6):468-72.
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    ABSTRACT: To systematically evaluate the ETS-related gene (ERG) alterations in the multifocal tumor context using whole-mount prostatectomy specimens from African and Caucasian American patients matched for age, pathologic grade and stage. Oncogenic activation of the ERG is the most common early genomic alteration in patients with prostate cancer (CaP) in Western countries. However, ERG alterations have not been systematically examined in African American patients with a known greater risk of CaP incidence and mortality. ERG oncoprotein expression was analyzed in 91 Caucasian and 91 African American patients with CaP, who were matched for age, Gleason score, and pathologic stage. A unique aspect of the present study was the evaluation of ERG in whole-mount prostatectomy sections, minimizing sampling bias and allowing the careful assessment of the ERG in the multifocal tumor context of CaP. The frequency of ERG-positive prostate tumors was significantly greater among Caucasian Americans than among African Americans when assessed in all tumor foci (41.9% vs 23.9%, P < .0001). A markedly greater frequency of ERG oncoprotein expression was noted between the index tumors of the Caucasian Americans (63.3%) and those of the African Americans (28.6%). Also, in the African American patients, the higher grade index tumors were predominantly ERG negative. ERG typing of CaP established a major difference between the index tumors of Caucasian and African American patients. ERG-negative index tumors might indicate a less favorable outcome for African American patients. The results of the present study underscore that typing of CaP for the ERG could enhance our understanding of the biologic differences between the examined ethnic groups.
    Urology 08/2012; 80(4):749-53. · 2.13 Impact Factor
  • Cancer Research 06/2012; 72(8 Supplement):2614-2614. · 9.28 Impact Factor
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    ABSTRACT: Oncogenic activation of ERG resulting from gene fusion is present in over half of all patients with prostate cancer in Western countries. Although the underlying genetic mechanisms have been extensively studied, evaluation of the ERG oncoprotein--the translational product of ERG gene fusions--has just begun. The robust correlation between ERG oncoprotein detection and gene fusion status enables rapid characterization of this protein in large patient cohorts. Recent studies have focused on characterizing the ERG oncoprotein and determining its potential role in the diagnosis and biological stratification of prostate cancer.
    Nature Reviews Urology 02/2012; 9(3):131-7. · 4.79 Impact Factor
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    ABSTRACT: Neural-cadherin is a member of the cadherin gene family encoding the N-cadherin protein that mediates cell adhesion. N-cadherin is a marker of Sertoli cells and is also expressed in germ cells of varying stages of maturation. The purpose of this study was to determine the presence and distribution of this protein by immunohistochemistry in 105 germ cell tumors of both single and mixed histological types and 12 gonadal stromal tumors. Twenty-four germ cell tumors consisted of one cell type and the remaining were mixed. Of the 23 seminomas in either pure or mixed tumors, 74% were positive. Two spermatocytic seminomas were positive. Of the 83 cases with yolk sac tumor, 99% were positive for N-cadherin. The teratomas were positive in 73% in neuroectodermal and / or glandular components. In contrast, 87% of embryonal carcinomas did not express N-cadherin. Only 17% of the syncytiotrophoblastic cells were positive for N-cadherin. In conclusion, N-cadherin expression is very helpful in the identification of yolk sac tumors. In addition to glypican-3 and Sal-like protein 4, N-cadherin can be beneficial for the diagnosis and classification of this subtype of testicular germ cell tumor. Nine of the 12 gonadal stromal tumors were positive to a variable extent.
    Journal of Cancer. 01/2012; 3:381-9.
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    ABSTRACT: The majority of prostate cancers (CaP) are detected in early stages with uncertain prognosis. Therefore, an intensive effort is underway to define early predictive markers of CaP with aggressive progression characteristics.
    Prostate cancer and prostatic diseases 12/2011; · 2.10 Impact Factor

Publication Stats

6k Citations
885.46 Total Impact Points


  • 2013
    • Rajiv Gandhi Cancer Institute & Research Centre
      New Dilli, NCT, India
  • 1994–2013
    • Uniformed Services University of the Health Sciences
      • Department of Surgery
      Maryland, United States
  • 2012
    • Tulane University
      New Orleans, Louisiana, United States
  • 1984–2012
    • Walter Reed National Military Medical Center
      • Department of Surgery
      Washington, Washington, D.C., United States
  • 1986–2011
    • Armed Forces Institute of Pathology
      Ralalpindi, Punjab, Pakistan
  • 2008
    • The Queen's Medical Center
      Honolulu, Hawaii, United States
  • 2007
    • National Institutes of Health
      • Division of Cancer Prevention
      Bethesda, MD, United States
  • 2001–2006
    • University of Maryland, Baltimore
      Baltimore, Maryland, United States
  • 2005
    • Northwestern Memorial Hospital
      Chicago, Illinois, United States
  • 1999–2000
    • Georgetown University
      • Department of Radiology
      Washington, D. C., DC, United States
    • Shady Grove Adventist Hospital
      Maryland, United States
  • 1997–1999
    • University of Cologne
      • • Department of Urology
      • • Department of Neurology
      Köln, North Rhine-Westphalia, Germany
  • 1998
    • The Catholic University of America
      • Department of Electrical Engineering and Computer Science
      Washington, D. C., DC, United States
  • 1990
    • The Washington Hospital
      Washington, Pennsylvania, United States
  • 1989
    • Auburn University
      Auburn, Alabama, United States