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  • Küçük Resim
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    The expression of GST and CYP isoenzymes in thyroid nodular hyperplasia and papillary thyroid cancer tissue: Correlation with clinical parameters
    (Entomology & Applied Science Research Letters-Easletters, 2016) Oguztuzun, Serpil; Ergn, Duygu; Kilic, Murat; Bozer, Busra; Simsek, Gulcin Guler; Bulus, Hakan
    This study investigated the immunohistochemical staining characteristics of glutathione-S-transferase (GST) pi(P), mu(M), theta(T), omega(O) and kappa(K) cytochrome P450 (CYP) A1, B1 and 2E1 isoenzymes in thyroid nodular hyperplasia (NH) and papillary thyroid cancer (PTC) tissues. For immunohistochemical studies, tissues from 18 patients with thyroid nodular hyperplasia, 28 patients with papillary thyroid cancer at the Kecioren Training and Research Hospital, Ankara, Turkey, were used. Relationships between GST and CYP isoenzyme expressions in NH and PTC tissues were examined by the Mann-Whitney U test, and clinicopathological data were examined by the Pearson Correlation Test and Regression Analysis. When the NH and PTC tissues from these cases were compared with respect to their staining intensity, GSTP1, GSTO1, GSTK1, CYP1A1, CYP2E1 expressions in PTC cells were significantly higher than those in NH epithelial cells (p< 0.05). There were no statistically significant differences in the CYP1B1, GSTT1 and GSTM1 expressions between benign and tumor epithelium (p> 0.05). There were significant association between GSTO1, GSTK1 expressions and sT3 levels in PTC (p< 0.05) and CYP1B1 expression in NH. There was a significant association between GSTO1 expression and smoking status in NH ( p< 0.05). There was no statistical relationship between the GSTM1, GSTT1, GSTP1, GSTO1, GSTK1, CYP1A1, CYP1B1, CYP2E1 isoenzyme expressions and the clinicopathological data (age, TSH, sT4 levels, tumor stage) ( p> 0.05). GSTP1, GSTO1, GSTK1, CYP1A1 and CYP2E1 isoenzymes may have roles in the carcinogenesis of the papillary thyroid cancer.
  • Küçük Resim
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    Expressions of CYP and GST Isoenzymes in Human Gastric Tumor and Non-Tumor Tissues
    (Akad Doktorlar Yayinevi, 2018) Simsek, Gulcin G.; Oguztuzun, Serpil; Bozer, Busra; Kilic, Murat; Kocdogan, Arzu K.; Kaygin, Pinar; Bulus, Hakan
    In this study we investigated the immunohistochemical staining characteristics of cytochrome P450 1A1 (CYP1A1), CYPB1, CYP2E1 and glutathione S-transferase P1 (GSTP1), GSTT1, GSTO1, GSTK1 isoenzymes in gastric tumor and surrounding tumor free (normal) gastric tissues from 40 patients. For immunohistochemical studies, tissues were obtained from 40 patients with gastric adenocarcinoma. Tumor and non-tumoral control tissues of patients were compared according to their staining intensity. Relationships between CYP and GST isoenzyme expressions in adenocarcinoma tissues were examined by the Mann Whitney-U test, and the clinicopathological data were examined by the Spearman's Rank Correlation test. CYP1B1, GSTT1, GSTO1 and GSTK1 expressions in gastric cancer cells were significantly higher than those in gastric normal epithelial cells (p < 0.05). However, CYP1A1, CYP2E1 and GSTP1 expressions were not significantly higher in tumor epithelium than those in normal epithelium in human gastric adenocancer (p < 0.05). Among the studied CYPs and GSTs, there was not statistically significant association between the studied isoenzyme expressions and age, gender and tumor grade ( p > 0.05). In patients with gastric adenocarcinoma, CYP1B1, GSTO1, GSTT1, and GSTK1 protein expressions are higher in tumor than normal gastric tissues.
  • [ X ]
    Öğe
    Immunohistochemical approach to obesity disease in terms of expression levels of glutathione s-transferase (sigma, zeta, theta) isozymes
    (2023) Davudov, Mahammad; Bulus, Hakan; Dirican, Onur; Kaygın, Pınar; Şımşek, Gülçin Güler; Sarıaltın, Sezen Yılmaz; Gürbüz, Fatıma Nurdan
    Objectives: Obesity is a complex multifactorial disease with recently increasing prevalence and incidence. Several studies have been conducted to explain the ethiology, pathophysiology, epidemiology, molecular and genetic mechanisms, and effective treatments of obesity. Glutathione S-transferase (GST) S1, GSTZ1, and GSTT1 are essential enzymes for oxidative stress and metabolism-related disorders. For this purpose, we aimed to reveal the role of GSTS1, GSTZ1, and GSTT1 in obesity. Methods: The gastric tissue samples were taken from the patients diagnosed with obesity who underwent bariatric surgery in Ankara Keçiören Training and Research Hospital General Surgery Clinic between 2017 and 2019. Immunostaining was performed on paraffin-embedded tissues to evaluate GSTS1, GSTZ1, and GSTT1 expressions. Laboratory data of the patients were recorded. All the results were analyzed statistically. Results: Weak GSTS1 expression was observed in 38.1% of tissues and moderate in 6.3%. 37.3% of the tissues presented weak GSTZ1 expression, and 11 (8.7%) displayed moderate. There were weak GSTT1 expressions in 7.1% of the tissues and moderate 0.8% of them. A positive and statistically significant correlation was observed between GSTS1 and GSTT1 expression levels ((r)=0.028, p = 0.010; p < 0.05). There were no significant differences between expression levels and gender, age, comorbidities, and medication usage (p > 0.05). Conclusions: GSTs, in particular GSTS1, GSTT1, and GSTZ1, might contribute to molecular mechanisms and the progression of obesity. In our study, GSTS1, GSTT1, and GSTZ1 were found to be moderately expressed in gastric tissues taken from obese patients. However, new studies using more samples and advanced techniques are needed to elucidate the relationship.
  • [ X ]
    Öğe
    Investigation of the role of CYP1A1 and CYP1B1 expressions in obesity susceptibility
    (2022) Polat, Fatih; Bulus, Hakan; Kaygın, Pınar; Dirican, Onur; Şımşek, Gülçin Güler; Sarıaltın, Sezen Yılmaz; Gurbuz, Nurdan
    Metabolik işleyiş, etkileri ve neden olduğu hastalıklar açısından daha multidisipliner bir bakış açısıyla anlaşılması gereken obezite, son yıllarda prevalansı ve insidansı artan hastalıklardan biri olarak görülmektedir. Bu hastalığın metabolik yolunda önemli enzim gruplarından biri olan sitokrom p450 (CYP1A1 ve CYP1B1) izozimlerinin rolünün ortaya konulması amaçlanmıştır. 2017-2019 yılları arasında Ankara Keçiören Eğitim ve Araştırma Hastanesi Genel Cerrahi Kliniği'nde obezite tanısı konulan ve bariatrik cerrahi, ksenobiyotik metabolizması uygulanan 152 hastaya immünohistokimya yöntemiyle CYP1A1 ve CYPB1 izoenzimlerinin ekspresyonu araştırılmıştır. CYP1A1 açısından elde edilen bulgular; 152 kişide CYP1A1 ve CYP1B1 immünohistokimya boyama düzeyleri incelenen dokuların %12.7'sinde CYP1A1 ekspresyonu gözlenmezken; %33.3, %32.5 ve %21.4'te zayıf bir CYP1A1 ifadesi gözlenmiştir. Dokuların %71.4'ünde CYP1B1 ekspresyonu görülmezken, dokuların %28.6'sında zayıf ekspresyon izlenmiştir. Hiçbir dokuda orta veya güçlü CYP1B1 ekspresyonu gözlenmemiştir. Kadın hastalardan alınan dokuların ortalama CYP1A1 ve CYP1B1 boyama seviyeleri erkek hastalardan daha yüksek bulunmuştur. Klinik verilerden diyabet parametresi (p