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Dive into the research topics where Nazan Özsan is active.

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Featured researches published by Nazan Özsan.


Blood | 2012

Genome-wide analysis reveals recurrent structural abnormalities of TP63 and other p53-related genes in peripheral T-cell lymphomas

George Vasmatzis; Sarah H. Johnson; Ryan A. Knudson; Rhett P. Ketterling; Esteban Braggio; Rafael Fonseca; David S. Viswanatha; Mark E. Law; N. Sertac Kip; Nazan Özsan; Stefan K. Grebe; Lori A. Frederick; Bruce W. Eckloff; E. Aubrey Thompson; Marshall E. Kadin; Dragana Milosevic; Julie C. Porcher; Yan W. Asmann; David I. Smith; Irina V. Kovtun; Stephen M. Ansell; Ahmet Dogan; Andrew L. Feldman

Peripheral T-cell lymphomas (PTCLs) are aggressive malignancies of mature T lymphocytes with 5-year overall survival rates of only ∼ 35%. Improvement in outcomes has been stymied by poor understanding of the genetics and molecular pathogenesis of PTCL, with a resulting paucity of molecular targets for therapy. We developed bioinformatic tools to identify chromosomal rearrangements using genome-wide, next-generation sequencing analysis of mate-pair DNA libraries and applied these tools to 16 PTCL patient tissue samples and 6 PTCL cell lines. Thirteen recurrent abnormalities were identified, of which 5 involved p53-related genes (TP53, TP63, CDKN2A, WWOX, and ANKRD11). Among these abnormalities were novel TP63 rearrangements encoding fusion proteins homologous to ΔNp63, a dominant-negative p63 isoform that inhibits the p53 pathway. TP63 rearrangements were seen in 11 (5.8%) of 190 PTCLs and were associated with inferior overall survival; they also were detected in 2 (1.2%) of 164 diffuse large B-cell lymphomas. As TP53 mutations are rare in PTCL compared with other malignancies, our findings suggest that a constellation of alternate genetic abnormalities may contribute to disruption of p53-associated tumor suppressor function in PTCL.


Modern Pathology | 2011

Specificity of IRF4 translocations for primary cutaneous anaplastic large cell lymphoma: a multicenter study of 204 skin biopsies.

David A. Wada; Mark E. Law; Eric D. Hsi; David J. DiCaudo; Linglei Ma; Megan S. Lim; Aieska de Souza; Nneka I. Comfere; Roger H. Weenig; William R. Macon; Lori A. Erickson; Nazan Özsan; Stephen M. Ansell; Ahmet Dogan; Andrew L. Feldman

Current pathologic criteria cannot reliably distinguish cutaneous anaplastic large cell lymphoma from other CD30-positive T-cell lymphoproliferative disorders (lymphomatoid papulosis, systemic anaplastic large cell lymphoma with skin involvement, and transformed mycosis fungoides). We previously reported IRF4 (interferon regulatory factor-4) translocations in cutaneous anaplastic large cell lymphomas. Here, we investigated the clinical utility of detecting IRF4 translocations in skin biopsies. We performed fluorescence in situ hybridization (FISH) for IRF4 in 204 biopsies involved by T-cell lymphoproliferative disorders from 182 patients at three institutions. In all, 9 of 45 (20%) cutaneous anaplastic large cell lymphomas and 1 of 32 (3%) cases of lymphomatoid papulosis with informative results demonstrated an IRF4 translocation. Remaining informative cases were negative for a translocation (7 systemic anaplastic large cell lymphomas; 44 cases of mycosis fungoides/Sézary syndrome (13 transformed); 24 peripheral T-cell lymphomas, not otherwise specified; 12 CD4-positive small/medium-sized pleomorphic T-cell lymphomas; 5 extranodal NK/T-cell lymphomas, nasal type; 4 gamma-delta T-cell lymphomas; and 5 other uncommon T-cell lymphoproliferative disorders). Among all cutaneous T-cell lymphoproliferative disorders, FISH for IRF4 had a specificity and positive predictive value for cutaneous anaplastic large cell lymphoma of 99 and 90%, respectively (P=0.00002, Fishers exact test). Among anaplastic large cell lymphomas, lymphomatoid papulosis, and transformed mycosis fungoides, specificity and positive predictive value were 98 and 90%, respectively (P=0.005). FISH abnormalities other than translocations and IRF4 protein expression were seen in 13 and 65% of cases, respectively, but were nonspecific with regard to T-cell lymphoproliferative disorder subtype. Our findings support the clinical utility of FISH for IRF4 in the differential diagnosis of T-cell lymphoproliferative disorders in skin biopsies, with detection of a translocation favoring cutaneous anaplastic large cell lymphoma. Like all FISH studies, IRF4 testing must be interpreted in the context of morphology, phenotype, and clinical features.


Blood | 2012

Expression of Myc, but not pSTAT3, is an adverse prognostic factor for diffuse large B-cell lymphoma treated with epratuzumab/R-CHOP

Mamta Gupta; Matthew J. Maurer; Linda Wellik; Mark E. Law; Jing Jing Han; Nazan Özsan; Ivana N. Micallef; Ahmet Dogan; Thomas E. Witzig

STAT3 regulates cell growth by up-regulating downstream targets, such as Myc. The frequency of phosphorylated STAT3 (pSTAT3) and Myc expression and their prognostic relevance is unknown within diffuse large B-cell lymphoma (DLBCL) germinal center B-cell (GCB) and non-GCB subtypes. pSTAT3 and Myc were studied by immunohistochemistry (IHC) on tumors from 40 DLBCL patients uniformly treated on a clinical trial of epratuzumab/rituximab-CHOP. A total of 35% of cases were pSTAT3-positive, and pSTAT3 positivity was more frequent in the non-GCB (P = .06) type but did not correlate with event-free survival (EFS). Myc expression was observed in 50% of cases and was more frequent in non-GCB type (P = .07). Myc-positive cases had inferior EFS in all patients, including the GCB and pSTAT3-positive cases, were more likely to express Myc (P = .06). Myc translocations involving the major breakpoint regions were found in 10% (3 of 29) of cases, and all 3 cases were GCB and had an inferior EFS (P = .09). pSTAT3, but not Myc expression, was correlated with elevated pretreatment serum cytokines, such as IL-10 (P = .05), G-CSF (P = .03), and TNF-α (P = .04). pSTAT3 IHC in DLBCL tumors has the potential to identify patients for STAT3 pathway-directed therapy; Myc IHC is a potential marker for inferior EFS in GCB patients.


Leukemia & Lymphoma | 2012

Absolute monocyte/lymphocyte count prognostic score is independent of immunohistochemically determined cell of origin in predicting survival in diffuse large B-cell lymphoma.

Luis F. Porrata; Kay Ristow; Thomas M. Habermann; Nazan Özsan; Ahmet Dogan; William R. Macon; Joseph P. Colgan; Thomas E. Witzig; David J. Inwards; Stephen M. Ansell; Ivana N. Micallef; Patrick B. Johnston; Grzegorz S. Nowakowski; Carrie A. Thompson; Svetomir N. Markovic

Abstract The absolute monocyte/lymphocyte count prognostic score (AMC/ALC score) has not been directly compared with the cell of origin (COO) to predict overall survival (OS) and progression-free survival (PFS) in diffuse large B-cell lymphoma (DLBCL). Thus, we retrospectively examined a new cohort of 99 patients with DLBCL treated from 2008 to 2010, (1) to validate whether AMC/ALC score affects survival, (2) to investigate whether AMC/ALC score is independent of COO to predict survival and (3) to assess whether AMC/ALC score can further stratify clinical outcomes by COO. By univariate analysis, the AMC/ALC score was a predictor for OS and PFS. On multivariate analysis performed including the COO and the International Prognostic Index, AMC/ALC score remained an independent predictor for OS and PFS. The AMC/ALC score was able to further stratify DLBCL clinical outcomes by COO. The AMC/ALC score was independent of COO and added to its ability to identify patients with high-risk disease.


Rheumatology International | 2007

Hodgkin’s lymphoma following treatment with etanercept in ankylosing spondylitis

Kenan Aksu; Seckin Cagirgan; Nazan Özsan; Gokhan Keser; Fahri Sahin

It has been well known that anti-TNF drugs might increase lymphoma risk in rheumatoid arthritis (RA), where the rate of lymphoma has already been increased. However, unlike RA, an increased rate of lymphoma has not been reported in ankylosing spondylitis (AS). Hereby, we present a case with AS developing Hodgkin’s lymphoma (HL) following 6 months of etanercept treatment. Pathological analysis revealed mixed cellular type of HL. Although we report a single case, it should be kept in mind that anti-TNF drugs might cause lymphoma development not only in RA, but also in AS.


Immunotherapy | 2012

Granulomatous skin lesions, severe scrotal and lower limb edema due to mycobacterial infections in a child with complete IFN-γ receptor-1 deficiency.

Neslihan Edeer Karaca; Stéphanie Boisson-Dupuis; Guzide Aksu; Jacinta Bustamante; Gulsen Kandiloglu; Nazan Özsan; Mine Hekimgil; Jean-Laurent Casanova; Necil Kutukculer

Interferon-γ receptor-1 (IFNγR1) deficiency is caused by mutations in the IFNγR1 gene and is characterized mainly by susceptibility to mycobacterial disease. Herein, we report an 8-month-old boy with complete recessive IFNγR1 deficiency, afflicted by recurrent mycobacterial diseases with Mycobacterium bovis, Mycobacterium tuberculosis, Mycobacterium avium intracellulare and Mycobacterium fortuitum. Genetic analysis showed a homozygous mutation (106insT) in the IFNγR1 gene leading to complete IFNγR1 deficiency. In addition, he had atypical mycobacterial skin lesions caused by M. avium intracellulare and developed scrotal and lower limb lymphedema secondary to compression of large and fixed inguinal lymphadenopathies. Hematopoietic stem cell transplantation was performed from a matched unrelated donor at 5 years of age; however, he died at 9 months post-transplant. To our knowledge, the patient is the first case with IL-12/IFN-γ pathway defect and severe lymphedema. We have also reviewed and summarized the literature related with IFNγR1 deficiency.


Auris Nasus Larynx | 2011

Primary diffuse large B-cell lymphoma of the lacrimal sac simulating chronic dacryocystitis ☆

Melis Palamar; Raşit Midilli; Nazan Özsan; Sait Egrilmez; Fahri Sahin; Ayse Yagci

Primary diffuse large B-cell lymphoma of the lacrimal sac is rare. Herein we report a 55-year-old female presented with epiphora in the right eye. Distention of the lacrimal sac secondary to nasolacrimal duct obstruction was observed. She was scheduled for external dacryocystorinostomy for the next month. When she came for surgery, a growing mass was recognised over the lacrimal sac region. On computer tomography scan, a subdermal mass causing nasal bone destruction was detected. Excisional biopsy of the mass was performed. Histopathologic and immunohistochemical evaluations revealed primary diffuse large B-cell non-Hodgkin lymphoma of the lacrimal sac. She was treated with cyclophospamide, vincristine, adriablastine and prednisone for eight courses combined with rituximab for 6 months. During a follow-up period of 25 months, patient is stable with no systemic disease. Although rare, lacrimal sac tumors can mimic dacryocystitis and must be considered in differential diagnosis. In suspicious cases incisional biopsy is recommended.


World Journal of Emergency Surgery | 2009

A rare cause of recurrent gastrointestinal bleeding: mesenteric hemangioma

Mircelal Kazimi; Murat Ulas; Cem Ibis; Mutlu Unver; Nazan Özsan; Funda Yilmaz; Galip Ersoz; Murat Zeytunlu; Murat Kilic; Ahmet Coker

Lower gastrointestinal hemorrhage accounts for approximately 20% of gastrointestinal hemorrhage. The most common causes of lower gastrointestinal hemorrhage in adults are diverticular disease, inflammatory bowel disease, benign anorectal diseases, intestinal neoplasias, coagulopathies and arterio-venous malformations. Hemangiomas of gastrointestinal tract are rare. Mesenteric hemangiomas are also extremely rare.We present a 25-year-old female who was admitted to the emergency room with recurrent lower gastrointestinal bleeding. An intraluminal bleeding mass inside the small intestinal segment was detected during explorative laparotomy as the cause of the recurrent lower gastrointestinal bleeding. After partial resection of small bowel segment, the histopathologic examination revealed a cavernous hemagioma of mesenteric origin.Although rare, gastrointestinal hemangioma should be thought in differential diagnosis as a cause of recurrent lower gastrointestinal bleeding.


Japanese Journal of Clinical Oncology | 2013

Anti-Yo Antibody-mediated Paraneoplastic Cerebellar Degeneration in a Female Patient with Pleural Malignant Mesothelioma

Ozgur Tanriverdi; Nezih Meydan; Sabri Barutca; Nazan Özsan; Duygu Gurel; Ali Veral

Paraneoplastic cerebellar degeneration is a rare non-metastatic complication of malignancies. It presents with acute or subacute onset of ataxia, dysarthria and intention tremor. Paraneoplastic cerebellar degeneration is most commonly associated with malignancies of the ovary, breast and lung. The anti-Yo (anti-Purkinje cells) antibodies that specifically damage the Purkinje cells of the cerebellum are found in the serum and cerebrospinal fluid. Anti-Yo-related paraneoplastic cerebellar degeneration is most commonly found in women with gynecological and breast cancers, but it is reported in other malignancies. Patients with paraneoplastic syndromes most often present with neurologic symptoms before an underlying cancer is detected. We report a case of anti-Yo-related paraneoplastic cerebellar degeneration associated with pleural malignant mesothelioma in a 51-year-old female patient. She presented to our department with a 2-week history after the last chemotherapy of progressive dizziness related to head movement, nausea, vomiting, ataxia and unsteady gait. A western blot assay was negative for anti-Hu, anti-Ri, anti-Ma2, anti-CV2 and anti-amphiphysin paraneoplastic antibody markers but positive for anti-Yo. In conclusion, we report a case of paraneoplastic cerebellar degeneration in a patient with pleural malignant mesothelioma because of the rarity of this neurologic presentation after the diagnosis of malignant mesothelioma and of the association with anti-Yo antibodies.


Thrombosis Journal | 2009

Non ST-segment elevation myocardial infarction in patient with essential thrombocythemia

Emin Alioglu; Nurullah Tuzun; Fahri Sahin; Buket Kosova; Serkan Saygı; Istemihan Tengiz; Ugur Turk; Nazan Özsan; E. Ercan

A 68-year-old woman presented with acute chest pain and a greatly increased platelet count. Cardiac catheterization revealed subtotal occlusion and a thrombus-like filling defect in the right coronary artery. The patient was successfully treated with intravenous tirofiban. Essential thrombocythemia was diagnosed based on bone marrow findings, clinical presentation and laboratory analysis. The relationship between intracoronary thrombus and essential thrombocythemia is discussed.

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Ahmet Dogan

Memorial Sloan Kettering Cancer Center

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