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Dive into the research topics where Aysegul Uner is active.

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Featured researches published by Aysegul Uner.


Cancer | 2004

The fragile genes FHIT and WWOX are inactivated coordinately in invasive breast carcinoma.

Gulnur Guler; Aysegul Uner; Nilufer Guler; Shuang-Yin Han; B S Dimitrios Iliopoulos; Walter W. Hauck; Peter McCue; Kay Huebner

FHIT and WWOX are a tumor suppressor and a candidate suppressor that encompass the FRA3B and FRA16D fragile sites at chromosomes 3p14.2 and 16q23.3–24.1, respectively. Reduced or absent Fhit expression has been reported in two‐thirds of invasive breast tumors in association with adverse prognostic factors. Loss of 16q has been reported frequently in low‐grade, invasive breast tumors.


Cancer | 2012

Prognostic significance of MYC, BCL2, and BCL6 rearrangements in patients with diffuse large B-cell lymphoma treated with cyclophosphamide, doxorubicin, vincristine, and prednisone plus rituximab.

Nalan Akyürek; Aysegul Uner; Mustafa Benekli; Ibrahim Barista

Diffuse large B‐cell lymphomas (DLBCLs) are a biologically heterogeneous group in which various gene alterations have been reported. The aim of this study was to investigate the frequency and prognostic impact of BCL2, BCL6, and MYC rearrangements in cyclophosphamide, doxorubicin, vincristine, and prednisone plus rituximab (R‐CHOP)‐treated DLBCL cases.


Pathology International | 2005

Concordant loss of fragile gene expression early in breast cancer development

Gulnur Guler; Aysegul Uner; Nilüfer Güler; Shuang-Yin Han; Dimitrios Iliopoulos; Peter McCue; Kay Huebner

The FHIT and WWOX genes encompass the FRA3B and FRA16D fragile sites at chromosomes 3p14.2 and 16q23.3, respectively. Reduced Fhit and Wwox expression has been reported in approximately two‐thirds of invasive breast tumors. Expression of these fragile gene products, as well as ErbB2 and p53, were evaluated immunohistochemically in 44 pure and 31 adjacent‐to‐invasive ductal carcinoma in‐situ (DCIS) cases. Reduced Fhit and Wwox expression were observed in (i) 70% and 68% of pure DCIS; (ii) 52% and 55% of DCIS adjacent‐to‐invasive tumor cases; and (iii) 20% and 50% of adjacent normal tissue in pure DCIS cases. Reduced Wwox expression in adjacent normal tissue was observed in 30% of cases in the DCIS adjacent‐to‐invasive group. Reduced Fhit and Wwox expression was observed in 61% of adjoining invasive tumors. In all normal, pure DCIS, and DCIS adjacent‐to‐invasive lesions, Fhit and Wwox expression was positively associated (P = 0.034, P = 0.042, P = 0.004, respectively) and in the invasive component there was a positive trend toward association (P = 0.075). Fhit and Wwox were more frequently reduced in high‐grade lesions in the DCIS adjacent‐to‐invasive (P = 0.025, P = 0.004, respectively). In the pure DCIS group, there was a statistically significant negative association between Fhit and ErbB2 expression in DCIS (P = 0.035). In summary, reduced Fhit and Wwox expression in in‐situ breast cancer was associated, which may contribute to the high‐grade DCIS–invasive tumor pathway.


Cancer Genetics and Cytogenetics | 2010

EGFR expression and gene copy number in triple-negative breast carcinoma

Berrak Gumuskaya; Murat Alper; Sema Hucumenoglu; Kadri Altundag; Aysegul Uner; Gulnur Guler

Most basal-like breast carcinomas are estrogen receptor negative, progesterone receptor negative, and cerb-B2/HER-2/neu negative--the so-called triple-negative breast carcinomas--with high epidermal growth factor receptor (EGFR) expression, which makes EGFR a target of treatment. We evaluated EGFR expression by immunohistochemistry (IHC) with two different clones (EGFR.31G7 and EGFR.25) and gene copy number by fluorescence in situ hybridization (FISH) with Locus specific identifier EGFR/CEP 7 dual probe in 62 triple-negative breast carcinomas. Any complete or incomplete membranous and/or cytoplasmic expression was regarded as IHC positive. Cases showing gene amplification (a ratio of EGFR gene to chromosome 7 of ≥ 2 or 15 copies per cell in ≥ 10% of cells) and high polysomy (≥ 4 copies in ≥ 40% of cells) were considered FISH po sitive. We detected EGFR.31G7 positivity in 38 of 62 cases (61.4%), which was composed of 12 of 62 (19.4%) cytoplasmic, 14 of 62 (22.6%) incomplete membranous, and 12 of 62 (19.4%) complete membranous staining. Among 38 of 49 (77.6%) EGFR.25-positive cases, 7 of 49 (14.3%) exhibited cytoplasmic, 10 of 49 (20.4%) exhibited incomplete membranous, and 21 of 49 (42.9%) exhibited complete membranous staining pattern. Ten of 62 (16.1%) FISH-positive cases were identified; 1 of 62 (1.6%) showed amplification, and the rest showed high polysomy. All FISH-positive cases were also found to be IHC positive (P = 0.01) by both EGFR clones. The amplified case displayed strong complete membranous staining with both clones. Among the high polysomic cases; 4 of 9 (44.4%) incomplete membranous, 4 of 9 (44.4%) complete membranous and 1 of 9 (11.1%) cytoplasmic expression of EGFR.31G7, and 6 of 8 (75%) complete membranous and 2 of 6 (25%) cytoplasmic expression of EGFR.25 were detected. Here, we report that membranous EGFR expression is associated with increased gene copy number (P = 0.035 for EGFR.31G7 and P = 0.026 for EGFR.25 clone). Because the markers to predict anti-EGFR treatment response in other system tumors such as EGFR mutation and amplification seem to be rare events in breast cancer, membranous staining pattern of EGFR might be the best way to decide the patient eligibility for anti-EGFR therapy.


Leukemia & Lymphoma | 2006

Over-expression of angiotensin-converting enzyme (CD 143) on leukemic blasts as a clue for the activated local bone marrow RAS in AML

Salih Aksu; Yavuz Beyazit; Ibrahim C. Haznedaroglu; Hande Canpinar; Murat Kekilli; Aysegul Uner; Nilgun Sayinalp; Yahya Buyukasik; Hakan Goker; Osman Özcebe

Local bone marrow renin-angiotensin system (RAS) is an autocrine-paracrine system affecting hematopoiesis. Angiotensin II type 1a (AT1a) receptors are present on the CD34+ hematopoietic stem cells. Angiotensin II stimulates the proliferation of bone marrow and umbilical cord blood hematopoietic progenitors. There are preliminary data that local RAS might also be involved in leukemogenesis. ACE hyper-function may lead to the acceleration of negative hematopoietic regulator peptide, AcSDKP, metabolism, which in turn lowers its level in the bone marrow micro-environment, finally removing the anti-proliferative effect of AcSDKP on the hematopoietic cells and blasts. Renin expression could have a role on the leukemia development and angiotensin may act as an autocrine growth factor for acute myeloid leukemia (AML) cells. The aim of this study is to search ACE (CD 143) surface antigen by flow-cytometric analyses on the leukemic blast cells taken from the bone marrow of the patients with AML. Bone marrow aspiration materials and peripheral blood samples were obtained from 11 patients with AML (eight males, three females; aged 46 (range 26–67) years) and six patients with non-malignant hematological disorders (four males, two females; aged 56 (range 22–71) years). ACE (CD 143) surface antigen was shown to be over-expressed in leukemic myeloid blast cells. ACE is positively correlated with bone marrow blast count. Elucidation of the pathological activity of the local RAS-mediated regulation of the leukemogenesis is both pathobiologically and clinically important, since the angiotensin peptides represent a molecular target in the disease management.


Apmis | 2011

The presence of Epstein–Barr virus (EBV) in diffuse large B-cell lymphomas (DLBCLs) in Turkey: special emphasis on ‘EBV-positive DLBCL of the elderly’

Aysegul Uner; Nalan Akyürek; Arzu Saglam; Samir Abdullazade; Nuket Uzum; Sevgen Onder; Ibrahim Barista; Mustafa Benekli

Uner A, Akyurek N, Saglam A, Abdullazade S, Uzum N, Onder S, Barista I, Benekli M. The presence of Epstein–Barr virus (EBV) in diffuse large B‐cell lymphomas (DLBCLs) in Turkey: special emphasis on ‘EBV‐positive DLBCL of the elderly’. APMIS 2011; 119: 309–16.


Journal of Breast Cancer | 2012

Efficiency of ultrasound and ultrasound-guided fine needle aspiration cytology in preoperative assessment of axillary lymph node metastases in breast cancer.

Aysegul Oz; Figen Başaran Demirkazık; Meltem Gulsun Akpinar; Isıl Soygur; Atac Baykal; Sevgen Onder; Aysegul Uner

Purpose We performed this study to detect preoperative axillary metastases with ultrasound (US)-guided fine needle aspiration biopsy (FNAB), to eliminate the need for time-consuming and costly sentinel lymph node (SLN) scintigraphy and biopsy steps in the treatment of breast cancer patients, and in that of with suspicious US findings, and to evaluate the accuracy of preoperative US-guided FNAB for patients with suspicious lymph node metastases on US. Methods Patients with a suspicious breast lump or histopathologically proven breast cancer underwent breast-axillary US. Increase in lymph node size, cortical thickening, non-hilar cortical flow, and hilar changes were evaluated with gray scale-color Doppler US. FNAB was performed if US results were suspicious for malignancy. Results Thirty-eight axillary lymph nodes (ALN) underwent FNAB. ALN dissection, SLN scintigraphy, and biopsy steps were bypassed in 23 axillas with positive ALN FNAB (60.5%). The sensitivity of ALN FNAB was 88.46%; specificity and positive predictive value were 100%; and negative predictive value was 66.6% (inadequate cytology included; 76.7%, 100%, 100%, 53.3%, respectively). Asymmetrical cortical thickening, non-hilar cortical flow, and increase in hypoechogenity were only detected in metastatic nodes. Cortical thickening, and lymph node and breast mass size was higher in the metastatic group. Conclusion By performing FNAB on suspicious lymph nodes, the routine, high-cost SLN scintigraphy and intraoperative gamma probe steps may be skipped, and axilla dissection can be performed directly. This leads to the elimination of the need for SLN investigation in more than half of the patients. The assessment of ALN metastases with preoperative US-guided FNAB is a cost-effective method with high specificity, that eliminates the need for costly and time-consuming SLN scintigraphy and biopsy steps, and helps in preoperative staging.


Apmis | 2008

Immunohistochemical expression of multidrug resistance proteins in mature T/NK-cell lymphomas.

Arzu Saglam; Mutlu Hayran; Aysegul Uner

Multidrug resistance (MDR) is defined as resistance of tumor cells to a wide spectrum of structurally and functionally unrelated drugs. One of the most important mechanisms in mediating MDR is that involving cellular drug efflux transporters. Drug resistance is a common and formidable obstacle to therapy in mature T/NK‐cell lymphomas and the MDR phenotype is thought to be one of the contributing mechanisms. In this study we assessed the immunohistochemical expression of P‐gp (P‐glycoprotein), MRP‐1 (multidrug resistance associated protein 1), BCRP (breast cancer resistance protein) and LRP (lung resistance protein) in 45 mature T/NK‐cell lymphomas diagnosed at our hospital. We detected P‐gp expression in 31% (13/42), MRP‐1 expression in 74% (31/42), BCRP in 78% (32/ 41) and LRP in 59% (26/44) of the cases. These findings show that our T/NK‐cell lymphoma cases display high frequency of MDR protein expression.


Clinical and Experimental Ophthalmology | 2009

Isolated extraocular muscle involvement as the ophthalmic manifestation of leukaemia

Hayyam Kiratli; Kadriye Erkan Balcı; Cigdem Himmetoglu; Aysegul Uner

Background:  Clinical and imaging features of patients with orbital leukaemia primarily involving extraocular muscles were evaluated.


Leukemia & Lymphoma | 2005

PTEN and p27 expression in mature T-cell and NK-cell neoplasms

Aysegul Uner; Arzu Saglam; ünsal Han; Mutlu Hayran; Arzu Sungur; Sevket Ruacan

PTEN is a tumor suppressor gene located on chromosome 10q23 and is amongst the most commonly mutated genes in human cancers. The lipid phosphatase activity of Pten enables it to dephosphorylate PIP3, thereby antagonizing growth factor stimulated PI3-kinase signaling mediated by AKT/PKB. The growth inhibition effect of PTEN has been shown to be mediated by p27 which is one of the important effector molecules downstream of the AKT pathway. Recently the importance of the Pten and AKT pathway in the regulation of the immune system and development of hematological malignancies has been shown. Loss of Pten and p27 expressions were examined immunohistochemically in 45 patients with peripheral T- and NK-cell lymphoma. Partial or complete loss of Pten was detected in 66.7% of the cases of anaplastic large cell lymphoma (ALCL) compared to only 12.5% of all other mature T-/NK-cell lymphomas combined. Loss of p27 was identified in 64.9% of cases, which showed a positive correlation with Pten loss. In this study, we showed that loss of Pten is more frequent in ALCL as compared to other mature T-/NK-cell lymphomas, which strongly correlates with the loss of p27 expression. Our findings provide further evidence for the importance of the deregulation of the PI3K-AKT pathway in ALCL.

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