Helen Koutselini
National and Kapodistrian University of Athens
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Publication
Featured researches published by Helen Koutselini.
Proceedings of the National Academy of Sciences of the United States of America | 2003
Hippokratis Kiaris; Ioulia Chatzistamou; Andrew V. Schally; Gabor Halmos; Jozsef L. Varga; Helen Koutselini; Anastasios Kalofoutis
Existing evidence indicates that, in addition to its neuroendocrine action, growth hormone-releasing hormone (GHRH) acts directly on several nonpituitary tissues, especially neoplasms, and stimulates cell proliferation. We have recently reported that a splice variant of the receptor (SV1) is expressed in various normal tissues and particularly in tumor tissues, producing mitogenic effects on GHRH binding. By using HEC-1A human endometrial carcinoma cells, which express endogenous SV1, we show that, in addition to its ability to mediate the mitogenic effects of GHRH, SV1 also possesses relatively high intrinsic, ligand-independent activity. By using an antisense RNA-based approach we found that SV1 ablation reduces the efficacy of colony formation and the rate of cell proliferation of HEC-1A cells in the absence of exogenous GHRH, and decreases their sensitivity to GHRH when the neurohormone is added to the culture media. This ligand-independent stimulation of cell proliferation appears to be a characteristic property of the truncated form of the receptor, because the expression of SV1 and not of the full-length GHRH receptor stimulated the proliferation of 3T3 fibroblasts in the absence of exogenous GHRH, whereas both forms mediated the proliferative effects of GHRH. Evaluation of 21 specimens of human primary endometrial carcinoma for expression of SV1 by immunohistochemistry indicated that in contrast to the GHRH receptor, which is absent, SV1 is expressed in ≈43% of the specimens. These findings indicate that SV1 can operate in a ligand-independent as well as a ligand-dependent manner. The overexpression of this form of GHRH receptor may be associated with carcinogenesis.
American Journal of Dermatopathology | 2006
Christos Cheretis; Frank Dietrich; Ioulia Chatzistamou; Katerina Politi; Eirini Angelidou; Hippokratis Kiaris; Souren Mkrtchian; Helen Koutselini
The role of endoplasmic reticulum (ER)-stress proteins in the pathogenesis of neoplasia remains obscure. ERp29 encodes for an ER protein that is thought to facilitate the transport of secretory proteins in the early secretory pathway. ERp29 is expressed at varying levels in virtually every tissue tested, yet its precise role remains obscure. To test if ERp29 is associated with the pathogenesis of skin cancer, in the present study we have assessed the expression of ERp29 in basal-cell carcinoma of the skin. A bank of 104 basal skin carcinoma, including 50 nodular, 29 infiltrating, 15 superficial, 7 sclerosing, 2 fibroepithelial, and 1 pigmented cell carcinoma, were assessed by immunohistochemistry for ERp29 expression. Thirty-nine (37.5%) of the samples tested expressed ERp29 with the infiltrating carcinomas displaying more intense (++,+++) immunoreactivity (6/29, P < 0.05) and the superficial carcinomas exhibiting the less intense anti-ERp29 staining (1/15, P < 0.05). Collectively our results suggest that ERp29 is expressed in a subset of basal-cell carcinoma of the skin with the infiltrating carcinomas exhibiting the highest incidence of immunopositivity. The role of ERp29 in the pathogenesis of the disease and its potential diagnostic value should be explored in future investigations.
Onkologie | 2005
John Kouvaris; Vassilis Kouloulias; Xenofon N. Papacharalampous; Helen Koutselini; Constantine Gennatas; George S. Limouris; Lambros Vlahos
Background: Acrometastases are very rare and have been identified in only a few cases on the foot. At the onset, they might be misdiagnosed as arthritis. Case Report: A 59-year-old woman with isolated metastasis to the talus, originating from breast carcinoma was treated by radiotherapy, letrazole, and intravenous bisphosphonates. Results: The review of the literature revealed that this is the first case of an isolated metastasis to the bone of talus from a breast carcinoma, while there are a few cases originating from other organs. The differential diagnosis of acrometastases may be difficult. Conclusion: Pain in the foot or hand of a patient with a known history of malignancy should be considered as potential metastasis.
European Journal of Gastroenterology & Hepatology | 2000
Helen Koutselini; Andreas C. Lazaris; Nikolaos Kavantzas; Thomae Kiritsi; Davaris P
Objective Classification of hepatic tumours and tumourlike conditions can sometimes be difficult to establish by light microscopy. Our aim was to determine the value of computerized interactive nuclear morphometry in the preoperative prediction of primary or metastatic malignancy as opposed to non‐malignant lesions, in fine‐needle aspirates (FNA) of hepatic lesions. Methods Alcohol‐fixed, Papanicolaou‐stained FNA smears of 99 histologically proven hepatocellular carcinomas (HCCs), metastatic neoplasms and benign lesions were measured by computerized image analysis with regard to nuclear major axis, minor axis, perimeter, area, shape factor and hyperchromasia. Data were coded, entered into a computerized database, and statistically analysed with SPSS programs. Results Tukey HSD test for multiple comparisons, assessed for all features except hyperchromasia, showed that the mean values of morphometric features of non‐malignant cells were significantly different from those of malignant cells, either primary or metastatic, whereas differences between morphometric characteristics of HCCs and metastatic neoplasms were insignificant. Kruskal‐Wallis analysis of variance revealed that hyperchromasia varied among the three groups of samples proportionally to the other nuclear features. The mean differences of all evaluated nuclear variables except minor axis were significant between grades II & III and grade IV HCCs. Morphometric mean values of well‐differentiated HCCs differed significantly in comparison with those of non‐malignant lesions; however, some degree of overlap was observed in the ranges of minor axis and hyperchromasia mean values. Conclusions The three most important cytological criteria of nuclear malignancy (hyperchromasia, enlargement and anisonucleosis), when quantified by morphometry, may be helpful in the differential diagnosis between non‐cancerous liver lesions and HCCs (even those of high differentiation), since all the morphometric data showed pronounced differences between malignant and benign groups. Morphometry may also be used as a complementary tool in the cytological grading of HCCs. Eur J Gastroenterol Hepatol 12:913‐921
Cytopathology | 2005
Ekaterini Politi; Andreas C. Lazaris; S. Lambropoulou; D. Alexopoulou; V. Kyriakidou; Helen Koutselini
Objective: To evaluate proliferating cell nuclear antigen (PCNA) and epidermal growth factor receptor (EGFR) expression in urine ThinPrep (TP) specimens, to compare these findings with clinical and histological features and to determine whether these immunomarkers are predictive of clinical stage.
Cytopathology | 2008
Ekaterini Politi; Andreas C. Lazaris; M. Kehriotis; Thomas Papathomas; Nikolakopoulou E; Helen Koutselini
Objective: The aim of the present study was to evaluate the expression of pan‐cadherin and β‐catenin in cervical smears with various types of infectious agents.
Journal of Obstetrics and Gynaecology Research | 2008
Vasileios D. Sioulas; Irene Lambrinoudaki; Ekaterini Politi; Aspasia Kyroudi; Theodoros N. Sergentanis; Constantinos Panoulis; Areti Augoulea; George Kaparos; Maria Creatsa; Helen Koutselini; Konstantinos Papadias
Aim: Epithelial cadherin (E‐cadherin), a transmembrane glycoprotein involved in calcium‐dependent homophilic cell‐cell adhesion, is expressed aberrantly during cervical carcinogenesis. E‐cadherin expression and putatively implicated predictors in healthy women remain a rather under‐investigated area. The objective of this study is to evaluate the possible associations between E‐cadherin expression and reproductive/lifestyle factors in cervical epithelial cells from postmenopausal women.
International Ophthalmology | 2016
Georgios A. Laspias; Georgia-Heleni Thomopoulou; Andreas C. Lazaris; Nikolaos Kavantzas; Helen Koutselini; Nikolaos Pagonis; Eugenia Tsapeli; Ekaterini Politi
Abstract The aim of the study is to evaluate and correlate the morphology and cell density of epithelial cells adhering to lens capsule surgically removed from the anterior central region with lens clarity and type of cataract present in patients with or without type 2 diabetes. Capsulorhexis specimens were obtained from patients who had undergone phacoemulsification cataract surgery. All the samples were centrifuged and stained by the aid of Papanicolaou technique and were observed under light microscope. We determinated the mean cell density, the degree of epithelial damage, and morphological indicators of cells such as cell area and the nucleus–plasma ratio. Patients with cataract demonstrated a statistical significant decrease in cell density and an heterogeneous cell picture in which enlarged cells dominated. In addition, type 2 diabetics with cataract had a significantly even lower mean epithelial cell density by the presence of larger cell area with smaller nucleus–plasma ratio. More pronounced alterations in the lens epithelium were correlated not only with the presence of cortical cataract, increased fasting blood sugar, and increased HbA1c but also with the prolonged duration of diabetes and the co-existence of diabetic retinopathy. It seems that density and morphology of the anterior lens epithelial cells determine the lens epithelium damage which is more profound in hyperglycemia and in cortical cataracts. The changes in lens epithelium seem to play an important role in cataractogenesis.
International Journal of Gynecological Cancer | 2008
V. Kapetanios; Andreas C. Lazaris; P. Bogris; S. Kouneli; Aphrodite Nonni; H. Arvaniti; E. Kouri; M. Tzavara; G. Giannakodimos; Helen Koutselini; E. Patsouris
The cell cycle control system includes cyclins, cyclin-dependent kinases (CDK), and their inhibitors (CDK1). Extracellular regulated kinase (ERK1/2) (p44 and p42 mitogen-activated protein kinases [MAPKs]) is a component of the MAPK pathway, which is associated with cyclin D1 and CDK. It is a critical signaling system for the induction of cell proliferation, differentiation, and cell survival. The aim of this study was to investigate the usefulness of ERK2 expression as a marker of biological aggressiveness complementary to cervical intraepithelial neoplasia (CIN) grade as well as to compare its expression in preinvasive lesions with that in invasive carcinoma. Paraffin-embedded sections of 146 CIN lesions (32 CIN I, 49 CIN II, and 43 CIN III) and 22 invasive cervical carcinomas (13 squamous and 9 adenocarcinomas) were used for the standard immunohistochemical procedure with the application of the ERK2 monoclonal antibody. ERK2 staining displayed a cytoplasmic and nuclear pattern. The staining intensity was gradually increased according to the severity of the dysplastic lesions; ERK2 immunoreactivity was significantly increased in high-grade dysplastic lesions (CIN II and CIN III) and invasive carcinomas by comparison to low-grade dysplastic lesions (CIN I) (P < 0.001). When high-grade lesions were separately assessed, the differences between each one of them and CIN I retained their statistical significance: CIN II versus CIN I (P < 0.001) and CIN III versus CIN I (P < 0.001). In conclusion, our study found a direct relationship between the increasing grade of the dysplastic cervical lesions and the intensity of ERK2 staining, thus implying a role of ERK2 as an early event in cervical carcinogenesis.
European Journal of Endocrinology | 2004
Ioulia Chatzistamou; Andrew V. Schally; Hippokratis Kiaris; Ekaterini Politi; Jozsef L. Varga; George Kanellis; Anastasios Kalofoutis; Agatha Pafiti; Helen Koutselini