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Dive into the research topics where Kristopher Attwood is active.

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Featured researches published by Kristopher Attwood.


PLOS ONE | 2012

NY-ESO-1 Cancer Testis Antigen Demonstrates High Immunogenicity in Triple Negative Breast Cancer

Foluso O. Ademuyiwa; Wiam Bshara; Kristopher Attwood; Carl Morrison; Stephen B. Edge; Christine B. Ambrosone; Tracey L. O’Connor; Ellis G. Levine; Anthony Miliotto; Erika Ritter; Gerd Ritter; Sacha Gnjatic; Kunle Odunsi

Purpose NY-ESO-1 cancer testis (CT) antigen is an attractive candidate for immunotherapy as a result of its high immunogenicity. The aim of this study was to explore the potential for NY-ESO-1 antigen directed immunotherapy in triple negative breast cancer (TNBC) by determining the frequency of expression by immunohistochemistry (IHC) and the degree of inherent immunogenicity to NY-ESO-1. Experimental Design 168 TNBC and 47 ER+/HER2- primary breast cancer specimens were used to determine NY-ESO-1 frequency by IHC. As previous studies have shown that patients with a robust innate humoral immune response to CT antigens are more likely to develop CD8 T-cell responses to NY-ESO-1 peptides, we evaluated the degree to which patients with NY-ESO-1 expression had inherent immunogenicity by measuring antibodies. The relationship between NY-ESO-1 expression and CD8+ T lymphocytes was also examined. Results The frequency of NY-ESO-1 expression in the TNBC cohort was 16% versus 2% in ER+/HER2- patients. A higher NY-ESO-1 score was associated with a younger age at diagnosis in the TNBC patients with NY-ESO-1 expression (p = 0.026). No differences in OS (p = 0.278) or PFS (p = 0.238) by NY-ESO-1 expression status were detected. Antibody responses to NY-ESO-1 were found in 73% of TNBC patients whose tumors were NY-ESO-1 positive. NY-ESO-1 positive patients had higher CD8 counts than negative patients (p = 0.018). Conclusion NY-ESO-1 is expressed in a substantial subset of TNBC patients and leads to a high humoral immune response in a large proportion of these individuals. Given these observations, patients with TNBC may benefit from targeted therapies directed against NY-ESO-1.


Molecular Endocrinology | 2012

RhoA as a mediator of clinically relevant androgen action in prostate cancer cells.

Lucy J. Schmidt; Kelly Duncan; Neelu Yadav; Kevin M. Regan; Alissa R. Verone; Christine M. Lohse; Elena Pop; Kristopher Attwood; Gregory E. Wilding; James L. Mohler; Thomas J. Sebo; Donald J. Tindall; Hannelore V. Heemers

Recently, we have identified serum response factor (SRF) as a mediator of clinically relevant androgen receptor (AR) action in prostate cancer (PCa). Genes that rely on SRF for androgen responsiveness represent a small fraction of androgen-regulated genes, but distinguish benign from malignant prostate, correlate with aggressive disease, and are associated with biochemical recurrence. Thus, understanding the mechanism(s) by which SRF conveys androgen regulation to its target genes may provide novel opportunities to target clinically relevant androgen signaling. Here, we show that the small GTPase ras homolog family member A (RhoA) mediates androgen-responsiveness of more than half of SRF target genes. Interference with expression of RhoA, activity of the RhoA effector Rho-associated coiled-coil containing protein kinase 1 (ROCK), and actin polymerization necessary for nuclear translocation of the SRF cofactor megakaryocytic acute leukemia (MAL) prevented full androgen regulation of SRF target genes. Androgen treatment induced RhoA activation, increased the nuclear content of MAL, and led to MAL recruitment to the promoter of the SRF target gene FHL2. In clinical specimens RhoA expression was higher in PCa cells than benign prostate cells, and elevated RhoA expression levels were associated with aggressive disease features and decreased disease-free survival after radical prostatectomy. Overexpression of RhoA markedly increased the androgen-responsiveness of select SRF target genes, in a manner that depends on its GTPase activity. The use of isogenic cell lines and a xenograft model that mimics the transition from androgen-stimulated to castration-recurrent PCa indicated that RhoA levels are not altered during disease progression, suggesting that RhoA expression levels in the primary tumor determine disease aggressiveness. Androgen-responsiveness of SRF target genes in castration-recurrent PCa cells continued to rely on AR, RhoA, SRF, and MAL and the presence of intact SRF binding sites. Silencing of RhoA, use of Rho-associated coiled-coil containing protein kinase 1 inhibitors, or an inhibitor of SRF-MAL interaction attenuated (androgen-regulated) cell viability and blunted PCa cell migration. Taken together, these studies demonstrate that the RhoA signaling axis mediates clinically relevant AR action in PCa.


Cancer Medicine | 2013

A contemporary analysis of morbidity and outcomes in cytoreduction/hyperthermic intraperitoneal chemoperfusion

Michelle Haslinger; Valerie Francescutti; Kristopher Attwood; Judith Andrea McCart; Marwan Fakih; John M. Kane; Joseph J. Skitzki

The risks and benefits of cytoreductive surgery combined with hyperthermic intraperitoneal chemotherapy (CS/HIPEC) continue to be debated by the oncology community. A retrospective analysis of contemporary data (2003–2011) was performed to provide objective information regarding surgical morbidity, mortality, and survival for patients undergoing CS/HIPEC at a comprehensive cancer center. While procedure‐associated morbidity was comparable to other major surgical oncology procedures, there was no operative or 30‐day mortality and 60‐day mortality was 2.7%. Increasing numbers of bowel resections were found to correlate to an increased incidence of deep surgical site infections (including abscess and enterocutaneous fistula) and need for reoperation which was in turn associated with a decreased overall survival (OS) and progression‐free survival (PFS). Five‐year OS rates varied by site of tumor origin and histology (disseminated peritoneal adenomucinosis [91.3%], Mesothelioma [80.8%], Appendiceal Adenocarcinoma [38.7%], and Colorectal Adenocarcinoma [38.2%]). With an acceptable morbidity and mortality rate, CS/HIPEC should be included as an effective treatment modality in the multidisciplinary care of select patients with peritoneal metastases.


Oncogene | 2016

YAP activation protects urothelial cell carcinoma from treatment-induced DNA damage

Eric Ciamporcero; H. Shen; Swathi Ramakrishnan; S. Yu Ku; Sreenivasulu Chintala; Li Shen; Remi Adelaiye; Kiersten Marie Miles; Chiara Ullio; Stefania Pizzimenti; Martina Daga; Gissou Azabdaftari; Kristopher Attwood; Candace S. Johnson; Jianliang Zhang; Giuseppina Barrera; Roberto Pili

Current standard of care for muscle-invasive urothelial cell carcinoma (UCC) is surgery along with perioperative platinum-based chemotherapy. UCC is sensitive to cisplatin-based regimens, but acquired resistance eventually occurs, and a subset of tumors is intrinsically resistant. Thus, there is an unmet need for new therapeutic approaches to target chemotherapy-resistant UCC. Yes-associated protein (YAP) is a transcriptional co-activator that has been associated with bladder cancer progression and cisplatin resistance in ovarian cancer. In contrast, YAP has been shown to induce DNA damage associated apoptosis in non-small cell lung carcinoma. However, no data have been reported on the YAP role in UCC chemo-resistance. Thus, we have investigated the potential dichotomous role of YAP in UCC response to chemotherapy utilizing two patient-derived xenograft models recently established. Constitutive expression and activation of YAP inversely correlated with in vitro and in vivo cisplatin sensitivity. YAP overexpression protected while YAP knockdown sensitized UCC cells to chemotherapy and radiation effects via increased accumulation of DNA damage and apoptosis. Furthermore, pharmacological YAP inhibition with verteporfin inhibited tumor cell proliferation and restored sensitivity to cisplatin. In addition, nuclear YAP expression was associated with poor outcome in UCC patients who received perioperative chemotherapy. In conclusion, these results suggest that YAP activation exerts a protective role and represents a pharmacological target to enhance the anti-tumor effects of DNA damaging modalities in the treatment of UCC.


PLOS ONE | 2013

Reduced mitochondrial DNA content associates with poor prognosis of prostate cancer in African American men.

Shahriar Koochekpour; Timothy Marlowe; Keshav K. Singh; Kristopher Attwood; Dhyan Chandra

Reduction or depletion of mitochondrial DNA (mtDNA) has been associated with cancer progression. Although imbalanced mtDNA content is known to occur in prostate cancer, differences in mtDNA content between African American (AA) and Caucasian American (CA) men are not defined. We provide the first evidence that tumors in AA men possess reduced level of mtDNA compared to CA men. The median tumor mtDNA content was reduced in AA men. mtDNA content was also reduced in normal prostate tissues of AA men compared to CA men, suggesting a possible predisposition to cancer in AA men. mtDNA content was also reduced in benign prostatic hyperplasia (BPH) tissue from AA men. Tumor and BPH tissues from patients ≥60 years of age possess reduced mtDNA content compared to patients <60 years of age. In addition, mtDNA content was higher in normal tissues from patients with malignant T3 stage disease compared to patients with T2 stage disease. mtDNA levels in matched normal prostate tissues were nearly doubled in Gleason grade of >7 compared to ≤7, whereas reduced mtDNA content was observed in tumors of Gleason grade >7 compared to ≤7. Together, our data suggest that AA men possess lower mtDNA levels in normal and tumor tissues compared to CA men, which could contribute to higher risk and more aggressive prostate cancer in AA men.


JAMA Surgery | 2015

Role of Repeat 18F-Fluorodeoxyglucose Positron Emission Tomography Examination in Predicting Pathologic Response Following Neoadjuvant Chemoradiotherapy for Esophageal Adenocarcinoma

Moshim Kukar; Raed M. Alnaji; Feraas Jabi; Timothy A. Platz; Kristopher Attwood; Hector R. Nava; Kfir Ben-David; David Mattson; Kilian E. Salerno; Usha Malhotra; Kazunori Kanehira; James Gannon; Steven N. Hochwald

IMPORTANCE Predicting complete pathologic response (CPR) preoperatively can significantly affect surgical decision making. There are conflicting data regarding positron emission tomography computed tomography (PET CT) characteristics and the ability of PET CT to predict pathologic response following neoadjuvant chemoradiotherapy in esophageal adenocarcinoma because most existing studies that include squamous histology have limited numbers and use nonstandardized PET CT imaging. OBJECTIVE To determine if PET CT characteristics are associated with CPR in patients undergoing trimodality treatment for esophageal adenocarcinoma. DESIGN, SETTING, AND PARTICIPANTS A retrospective medical record review was conducted at a large tertiary cancer center from a prospectively maintained database from January 1, 2005, to December 31, 2012. Inclusion criteria were patients undergoing esophagectomy for locally advanced esophageal adenocarcinoma post-neoadjuvant chemoradiotherapy with 2 standardized PET CT studies done at our institution (pre-neoadjuvant chemoradiotherapy and post-neoadjuvant chemoradiotherapy) for review. Data collected included clinical, pathologic, imaging, and treatment characteristics. MAIN OUTCOME AND MEASURE The primary study outcome was the association of PET CT characteristics with histologic confirmed pathologic response. RESULTS Of the total participants, 77 patients met the inclusion criteria. Twenty-two patients (28.6%) had CPR vs 55 patients (71.4%) who had incomplete pathologic response. The 2 groups were similar in age, sex, race/ethnicity, comorbid conditions, Eastern Cooperative Oncology Group status, tumor grade, chemotherapy, and radiation regimen and days between the 2 PET CTs. The mean prestandardized uptake variable (SUV; 14.5 vs 11.2; P = .05), δ SUV (10.3 vs 5.4; P = .02), and relative δ SUV (0.6 vs 0.4; P = .02) were significantly higher in those with CPR vs incomplete pathologic response. Using the Youden Index, a δ SUV value less than 45% was predictive of residual disease with a positive predictive value of 91.7% (95% CI, 73-99; P < .05). CONCLUSIONS AND RELEVANCE To our knowledge, this is the largest study examining the role of PET CT characteristics in esophageal adenocarcinoma for patients undergoing neoadjuvant chemoradiotherapy that demonstrates that δ SUV of less than 45% is associated with patients with residual disease but not CPR. Based on the findings from our study, the current recommendation is still surgical resection regardless of the posttherapy PET SUV in the primary tumor. However, our study highlights the ability to detect patients with residual disease and the need to critically evaluate these patients for consideration of additional therapies.


Medical Physics | 2011

Statistical variability and confidence intervals for planar dose QA pass rates.

D Bailey; Benjamin E. Nelms; Kristopher Attwood; L Kumaraswamy; Matthew B. Podgorsak

PURPOSE The most common metric for comparing measured to calculated dose, such as for pretreatment quality assurance of intensity-modulated photon fields, is a pass rate (%) generated using percent difference (%Diff), distance-to-agreement (DTA), or some combination of the two (e.g., gamma evaluation). For many dosimeters, the grid of analyzed points corresponds to an array with a low areal density of point detectors. In these cases, the pass rates for any given comparison criteria are not absolute but exhibit statistical variability that is a function, in part, on the detector sampling geometry. In this work, the authors analyze the statistics of various methods commonly used to calculate pass rates and propose methods for establishing confidence intervals for pass rates obtained with low-density arrays. METHODS Dose planes were acquired for 25 prostate and 79 head and neck intensity-modulated fields via diode array and electronic portal imaging device (EPID), and matching calculated dose planes were created via a commercial treatment planning system. Pass rates for each dose plane pair (both centered to the beam central axis) were calculated with several common comparison methods: %Diff/DTA composite analysis and gamma evaluation, using absolute dose comparison with both local and global normalization. Specialized software was designed to selectively sample the measured EPID response (very high data density) down to discrete points to simulate low-density measurements. The software was used to realign the simulated detector grid at many simulated positions with respect to the beam central axis, thereby altering the low-density sampled grid. Simulations were repeated with 100 positional iterations using a 1 detector/cm(2) uniform grid, a 2 detector/cm(2) uniform grid, and similar random detector grids. For each simulation, %/DTA composite pass rates were calculated with various %Diff/DTA criteria and for both local and global %Diff normalization techniques. RESULTS For the prostate and head/neck cases studied, the pass rates obtained with gamma analysis of high density dose planes were 2%-5% higher than respective %/DTA composite analysis on average (ranging as high as 11%), depending on tolerances and normalization. Meanwhile, the pass rates obtained via local normalization were 2%-12% lower than with global maximum normalization on average (ranging as high as 27%), depending on tolerances and calculation method. Repositioning of simulated low-density sampled grids leads to a distribution of possible pass rates for each measured/calculated dose plane pair. These distributions can be predicted using a binomial distribution in order to establish confidence intervals that depend largely on the sampling density and the observed pass rate (i.e., the degree of difference between measured and calculated dose). These results can be extended to apply to 3D arrays of detectors, as well. CONCLUSIONS Dose plane QA analysis can be greatly affected by choice of calculation metric and user-defined parameters, and so all pass rates should be reported with a complete description of calculation method. Pass rates for low-density arrays are subject to statistical uncertainty (vs. the high-density pass rate), but these sampling errors can be modeled using statistical confidence intervals derived from the sampled pass rate and detector density. Thus, pass rates for low-density array measurements should be accompanied by a confidence interval indicating the uncertainty of each pass rate.


Embo Molecular Medicine | 2014

Neoadjuvant antiangiogenic therapy reveals contrasts in primary and metastatic tumor efficacy

John M. L. Ebos; Michalis Mastri; Christina R. Lee; Amanda Tracz; John M. Hudson; Kristopher Attwood; William Cruz-Munoz; Christopher Jedeszko; Peter N. Burns; Robert S. Kerbel

Thousands of cancer patients are currently in clinical trials evaluating antiangiogenic therapy in the neoadjuvant setting, which is the treatment of localized primary tumors prior to surgical intervention. The rationale is that shrinking a tumor will improve surgical outcomes and minimize growth of occult micrometastatic disease—thus delaying post‐surgical recurrence and improving survival. But approved VEGF pathway inhibitors have not been tested in clinically relevant neoadjuvant models that compare pre‐ and post‐surgical treatment effects. Using mouse models of breast, kidney, and melanoma metastasis, we demonstrate that primary tumor responses to neoadjuvant VEGFR TKI treatment do not consistently correlate with improved post‐surgical survival, with survival worsened in certain settings. Similar negative effects did not extend to protein‐based VEGF pathway inhibitors and could be reversed with altered dose, surgical timing, and treatment duration, or when VEGFR TKIs are combined with metronomic ‘anti‐metastatic’ chemotherapy regimens. These studies represent the first attempt to recapitulate the complex clinical parameters of neoadjuvant therapy in mice and identify a novel tool to compare systemic antiangiogenic treatment effects on localized and disseminated disease.


Annals of Surgery | 2018

Enhanced Recovery After Surgery for Noncolorectal Surgery?: A Systematic Review and Meta-analysis of Major Abdominal Surgery.

Anthony Visioni; Rupen Shah; Emmanuel Gabriel; Kristopher Attwood; Moshim Kukar; Steven Nurkin

Objective: To evaluate the impact of enhanced recovery after surgery (ERAS) protocols across noncolorectal abdominal surgical procedures. Background: ERAS programs have been studied extensively in colorectal surgery and adopted at many centers. Several studies testing such protocols have shown promising results in improving postoperative outcomes across various surgical procedures. However, surgeons performing major abdominal procedures have been slower to adopt these ERAS protocols. Methods: A systematic review was performed using “enhanced recovery after surgery” or “fast track” as search terms and excluded studies of colorectal procedures. Primary endpoints for the meta-analysis include length of stay (LOS) and complication rate. Secondary endpoints were time to first flatus, readmission rate, and costs. Results: A total of 39 studies (6511 patients) met inclusion and exclusion criteria. Among them 14 studies were randomized trials, and the remaining 25 studies were cohort studies. Meta-analysis showed a decrease in LOS of 2.5 days (95% confidence interval, CI: 1.8–3.2, P < 0.001) and a complication rate of 0.70 (95% CI: 0.56–0.86, P = 0.001) for patient treated in ERAS programs. There was also a significant reduction in time to first flatus of 0.8 days (95% CI: 0.4–1.1, P < 0.001) and cost reduction of


British Journal of Dermatology | 2015

Identification of a new disease cluster of pemphigus vulgaris with autoimmune thyroid disease, rheumatoid arthritis and type I diabetes

A. Parameswaran; Kristopher Attwood; R. Sato; Kristina Seiffert-Sinha; Animesh A. Sinha

5109.10 (95% CI:

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Emmanuel Gabriel

Roswell Park Cancer Institute

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Steven Nurkin

Roswell Park Cancer Institute

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Steven N. Hochwald

Roswell Park Cancer Institute

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Moshim Kukar

Roswell Park Cancer Institute

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James L. Mohler

Roswell Park Cancer Institute

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Diana Mehedint

Roswell Park Cancer Institute

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Thomas Schwaab

Roswell Park Cancer Institute

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Boris W. Kuvshinoff

Roswell Park Cancer Institute

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Eric C. Kauffman

Roswell Park Cancer Institute

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