Yazar "Kaygin, Pinar" seçeneğine göre listele
Listeleniyor 1 - 9 / 9
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Chemoresistance in Malignant Intracranial Tumors: Longer Survival with Negative MDR1 Expression(Turkish Neurosurgical Soc, 2021) Ezgu, Mehmet Can; Kural, Cahit; Simsek, Gulcin Guler; Kaygin, Pinar; Oguztuzun, Serpil; Kirik, Alparslan; Yasar, SonerAIM: To analyze the Glutathione S-transferase (GST)-P, GST-M, cytochrome p450 (CYP)1-A1, CYP1-B1, and multidrug resistance (MDR)-1 expressions in malignant intracranial tumor (ICT)s, and to elicit their role on patient survival. MATERIAL and METHODS: GST-P, GST-M, CYP1-A1, CYP1-B1, and MDR-1 expressions were analyzed using immunostaining in 149 samples from 141 patients with preoperative ICT diagnosis. The case characteristics were reviewed, and the enzyme expressions were equated based on the age, gender, and tumor type. Then, 77 of 141 patients with malignant ICT and complete medical records postoperative were also investigated in detail for the relationship between the diagnosis, enzyme expression, and overall survival. RESULTS: The average age was 49.44 years, with 83 (58.45%) male patients. Among the 77 malignant ICTs, 38 (49.3%) and 29 were glial tumors and metastases, respectively, with a 13.35-month overall survival. Patients with metastatic tumor have approximately threefold higher GSTP level than those with glial tumors. MDR-1 expression was approximately twofold higher in > 60-year-old patients. No statistically significant association was found between patients' smoking behaviors, alcohol consumption, and overall survival. Only MDR-1 expression was correlated with overall survival. Better overall survival was observed in patients with a negative MDR-1 expression than those with a positive one. CONCLUSION: MDR-1 is an important indicator of survival in malignant intracranial tumor patients. Longer survival is associated with negative MDR-1 expression.Öğe Describing the Expression Profiles of Glutathione S-Transferase Mu and Tumor Protein 53 in Brain Tumor Tissue(Erciyes Univ Sch Medicine, 2024) Dirican, Onur; Kaygin, Pinar; Lti, Sezen Yilmaz Saria; Yilmaz, Can; Simsek, Gulcin; Oguztuzun, Serpil; Coban, TuelayObjective: This study aims to explore the expression profiles of the glutathione S-transferaseMu (GST-M) isozyme and tumor protein 53 (p53) in both healthy and tumorous brain tissues. The findings are compared with clinical features and lifestyle factors to identify potential associations or correlations. Materials and Methods: We retrospectively analyzed the medical records of 149 patients diagnosed with primary or metastatic intracranial tumors. The expression levels of GST-M and p53 proteins were assessed in healthy and tumorous brain tissues using immunohistochemical staining. We also evaluated the associated clinical features and lifestyle factors. Results: There was a significant difference in the expression levels of GST-M between tumorous and healthy brain tissues, with tumor tissues showing higher expression (p<0.0001). Conversely, robust p53 expression was absent in both normal (97.3%) and tumor (78.5%) tissues. Nevertheless, a significantly higher prevalence of samples with p53 expression was found in the tumor group (p<0.0001). No associations were found between expression levels and clinical features or lifestyle risk factors. Furthermore, GST-M and p53 expression did not impact postoperative survival rates. Conclusion: The findings indicate an elevated expression of GST-M in brain tumor tissues, suggesting a potential role for GST-M in brain tumorigenesis.Öğe Expression of Sigma-Class Glutathione-S-Transferase in Fetal and Pediatric Filum Terminale Samples: A Comparative Study(Mdpi, 2019) Kural, Cahit; Ogurtuzun, Serpil; Simsek, Gulcin Guler; Guresci, Servet; Kaygin, Pinar; Yasar, Soner; Izci, YusufBackground and objectives: The pathophysiology of tethered cord syndrome (TCS) in children is not well elucidated. An inelastic filum terminale (FT) is the main factor underlying the stretching of the spinal cord in TCS. Our study aimed to investigate the expression of glutathione-S-transferase (GST) in children and fetal FT samples in order to understand the relationship between this enzyme expression and the development of TCS. Materials and Methods: FT samples were obtained from ten children with TCS (Group 1) and histological and immunohistochemical examinations were performed. For comparison, FT samples from fifteen normal human fetuses (Group 2) were also analyzed using the same techniques. Statistical comparison was made using a Chi-square test. Results: Positive GST-sigma expression was detected in eight (80%) of 10 samples in Group 1. The positive GST-sigma expression was less frequent in nine (60%) of 15 samples from Group 2. No statistically significant difference was detected between the two groups (p = 0.197). Conclusions: Decreased FT elasticity in TCS may be associated with increased GST expression in FT. More prospective studies are needed to clarify the mechanism of the GST-TCS relationship in children.Öğe 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, HakanIn 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.Öğe Glutathione S-Transferases and Cytochrome P450 Enzyme Expression in Patients with Intracranial Tumors: Preliminary Report of 55 Patients(Karger, 2019) Kural, Cahit; Kocdogan, Arzu Kaya; Simsek, Gulcin Guler; Oguztuzun, Serpil; Kaygin, Pinar; Yilmaz, Irmak; Izci, YusufObjective: Intracranial tumors are one of the most frightening and difficult-to-treat tumor types. In addition to surgery, protocols such as chemotherapy and radiotherapy also take place in the treatment. Glutathione S-transferase (GST) and cytochrome P450 (CYP) enzymes are prominent drug-metabolizing enzymes in the human body. The aim of this study is to show the expression of GSTP1, GSTM1, CYP1A1, and CYP1B1 in different types of brain tumors and compare our results with those in the literature. Subjects and Methods: The expression of GSTP1, GSTM1, CYP1A1, and CYP1B1 was analyzed using immunostaining in 55 patients with intracranial tumors in 2016-2017. For GST and CYP expression in normal brain tissue, samples of a portion of surrounding normal brain tissue as well as a matched far neighbor of tumor tissue were used. The demographic features of the patients were documented and the expression results compared. Results: The mean age of the patients was 46.72 years; 29 patients were female and 26 were male. Fifty-seven specimens were obtained from 55 patients. Among them, meningioma was diagnosed in 12, metastases in 12, glioblastoma in 9, and pituitary adenoma in 5. The highest GSTP1, GSTM1, and CYP1A1 expressions were observed in pituitary adenomas. The lowest GSTP1 expression was detected in glioblastomas and the lowest CYP1B1 expression in pituitary adenomas. Conclusion: GSTP1 and CYP expression is increased in intracranial tumors. These results should be confirmed with a larger series and different enzyme subtypes. (c) 2018 The Author(s) Published by S. Karger AG, BaselÖğe Glutathione-S-Transferase And P53 Expressions In Human Malignant, Benign And Metastasis Ovarian Tumor Tissues(Wiley, 2019) Dirican, Onur; Kaygin, Pinar; Oguztuzun, Serpil; Erdem, Aysegul; Simsek, Gulcin Guler; Sarialtin, Sezen Yilmaz; Coban, Tulay…Öğe Immunocytochemical Evaluation of Glutathione-S-Transferase P1 Enzyme in Patients with Rheumatoid Arthritis(Wiley, 2019) Dirican, Onur; Kaygin, Pinar; Oguztuzun, Serpil; Simsek, Gulcin Guler; Hayat, Buket; Sarialtin, Sezen Yilmaz; Coban, Tulay…Öğe NLRP3 Expression in Peripheral Blood Mononuclear Cells of Patients with Rheumatoid Arthritis(Society of Pharmaceutical Sciences of Ankara (FABAD), 2023) Sarialtin, Sezen Yilmaz; Küçükşahin, Orhan; Nural, Cemil; Kozaci, Leyla Didem; Kaygin, Pinar; Şimşek, Gülçin Güler; O?uztüzün, SerpilRheumatoid arthritis (RA) is a systemic autoimmune disease characterized by painful, swollen, and inflamed joints. Individual, genetic, and environmental factors influence the development of the disease, which causes involvement not only in the joints but also in other extra-articular tissues. However, the etiopathogenesis of the disease has not yet been fully elucidated. NLRP3, a crucial component of the innate immune system, may contribute to recurrent and chronic inflammation, resulting in inflammation-related diseases. Therefore, we aimed to examine the expression pattern of NLRP3 in peripheral blood mononuclear cells isolated from patients with RA using immunocytochemical approaches in this study. Our findings demonstrated that NLRP3 expression was significantly increased in patients with RA compared to the healthy controls (p<0.01). The highest expression among the patient groups was observed in the active period cases, and this expression considerably increased compared to the control group (p<0.01). Patients in the remission period possessed the lowest expression among the patient groups. Since female gender is considered an independent risk factor for the disease, the effect of gender on expressions was also investigated. NLRP3 was expressed at higher levels in female patients than in males; however, this difference was not significant (p>0.05). The expression patterns of the patient and control groups suggest that NLRP3 may be involved in the development and progression of the disease. To our knowledge, our study is the first research investigating NLRP3 expression profile in peripheral blood mononuclear cells obtained from patients with RA using immunocytochemical approaches. The results of our study highlight significant aspects. However, further research using more sensitive methods with a larger number of cases is required to assess the function of NLRP3 in RA and to provide a deeper insight into the mechanism. © 2023 Society of Pharmaceutical Sciences of Ankara (FABAD). All rights reserved.Öğe The Administration of Steroids and its Impact on Caspase-3 Expression in Pediatric Adenoid Hypertrophy(Springer India, 2024) Apaydin, Emre; Yasar, Buse; Simsek, Gulcin; Kaygin, Pinar; Sarialtin, Sezen Yilmaz; Dirican, Onur; Cetin, Hazal EylemObjectiveAdenoid hypertrophy is a prevalent pediatric condition, often necessitating surgical intervention. Intranasal steroid administration shows promise as a conservative treatment, particularly by inducing apoptosis in adenoidal cells, leading to a reduction in adenoid size and inflammation. This study aims to characterize the expression profile of caspase-3 as an apoptotic inducer protein in inflammatory and epithelial adenoid tissues and explore its association with steroid administration. MethodsWe performed immunohistochemical staining for caspase-3 proteins in adenoid tissues obtained from 51 pediatric patients aged between 2.5 and 12 years (mean age: 6.09 +/- 2.1 years) who underwent adenoid surgery. A retrospective analysis of clinical data was conducted, categorizing participants into steroid treatment receivers (n = 25) and non-receivers (n = 26). Subsequently, the lymphoid inflammatory tissue and epithelial tissue from the adenoid were compared in terms of caspase-3 protein expression, and associated clinical variables were assessed. ResultsImmunohistochemical analysis revealed significant caspase-3 expression in inflammatory tissues. The expression levels were scored, and no significant correlation was observed between inflammation and epithelium based on caspase-3 expression (correlation coefficient = 0.143; p > 0.05). Furthermore, demographic and clinical characteristics did not show a statistically significant difference in caspase-3 expression levels. ConclusionCaspase-3 expression was significant in inflammatory adenoid tissue, but it showed no association with nasal steroid administration.
