Ev Ev

Prof. Dr. Ev Ev

orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
31 October 2025 in BMC Oral Health
Verified
Journal Article
Open access
PDF file
SSSena Sen
Sena Sen
CDCan Doruk
Can Doruk
EEEv Ev
Ev Ev
VOVakur Olgac
Vakur Olgac
GAGülsüm Ak
Gülsüm Ak
SEMRA DEMOKANSEMRA DEMOKAN
SEMRA DEMOKAN
Oral squamous cell carcinoma (OSCC) remains a major global health burden, often diagnosed at advanced stages, with limited survival improvement. Epigenetic dysregulation, particularly promoter hypermethylation, plays a significant role in OSCC pathogenesis. Previous study by Demokan et al. identified Gamma-Aminobutyric Acid Receptor Beta-2 (GABRB2) as a candidate gene subject to methylation-dependent transcriptional silencing. This study aimed to evaluate the methylation and expression profiles of GABRB2 in OSCC and to explore its potential as a diagnostic biomarker. Tissue and serum samples from 48 OSCC patients and 15 healthy controls were analyzed for GABRB2 promoter methylation via quantitative methylation-specific PCR and for gene expression levels via quantitative real-time PCR. Relationships between methylation, expression levels, clinicopathological parameters, and patient outcomes were statistically assessed. GABRB2 promoter hypermethylation was detected in 14.6% of tumor samples, predominantly in floor of the mouth and buccal tumors. Decreased GABRB2 expression was observed in 52.1% of tumor tissues compared to matched-normal tissues, while 22.9% of tumors exhibited increased expression. Methylation-dependent expression loss was confirmed in 71.4% of methylated tumors. Notably, decreased expression and hypermethylation of GABRB2 were correlated with poor prognosis parameters (p < 0.05). ROC analysis showed moderate discrimination for GABRB2 expression in distinguishing tumor from normal tissues (AUC = 0.635, p = 0.022), while serum-based analysis demonstrated poor diagnostic performance. Survival analysis revealed no statistically significant prognostic impact of GABRB2 expression levels (p > 0.05). However, alcohol consumption (p = 0.006) and recurrence developed (p = 0.030) as independent predictors of poor prognosis in multivariate analysis. Our study suggests that there was association between methylation-based expression loss of GABRB2 with OSCC’ subgroups. To our knowledge, this is the first study to investigate GABRB2 gene methylation and expression profiling in both invasive/non-invasive samples from OSCC patients. Hypermethylation in the newly identified candidate GABRB2 gene may play a role in the development of tumors originating from the mouth floor and buccal anatomical regions of the oral cavity. However, since the loss of expression seen in the majority of our patients, we thought that only methylation may not the inhibition mechanism for GABRB2 gene decreased expression. The new identified candidate gene may be specific for the OSCC’s subgroups.

25 June 2021 in Medical Oncology
Verified
Journal Article
Closed access
PDF file
LALevent Aydemir
Levent Aydemir
SBSinem Bireller
Sinem Bireller
BEBaris Ertugrul
Baris Ertugrul
GKGoksu Kasarci
Goksu Kasarci
MAMerve Nur Atas
Merve Nur Atas
BCBedia Cakmakoglu
Bedia Cakmakoglu

30 October 2025 in Biology
Verified
Journal Article
Open access
PDF file
MOMustafa Onel
Mustafa Onel
Hayriye Kırkoyun UysalHayriye Kırkoyun Uysal
Hayriye Kırkoyun Uysal
EEEv Ev
Ev Ev
UAUtkucan Ayeser
Utkucan Ayeser
Kutay SarsarKutay Sarsar
Kutay Sarsar
AAAli Agacfidan
Ali Agacfidan
(1) Background: This study investigated the presence of human papillomavirus (HPV), HPV genotypes, Epstein–Barr virus (EBV), cytomegalovirus (CMV) and herpes simplex virus (HSV) in patients with Head and Neck Cancer (HNC) at both molecular and serological levels. (2) Methods Fifty patients with histopathologically confirmed HNC who were admitted to the Department of Otorhinolaryngology, Istanbul Faculty of Medicine. Viral DNA was detected using quantitative real-time PCR, and serological IgM and IgG antibodies were analyzed using the CMIA method; (3) Results: In blood samples, CMV and HSV DNA were not detected, whereas EBV DNA was identified in 2% and HPV DNA in 4% of patients. In tumor tissues, CMV DNA was detected in 8%, EBV DNA in 10%, and HPV DNA in 6%; HSV DNA is 6%. HPV genotypes 18, 45, and 69 were found in tissue samples. Serologically, IgG positivity for CMV, EBV, and HSV-1 exceeded 90%, whereas IgM positivity was low and not statistically significant; (4) Conclusions: HPV, EBV, and CMV DNA were detected at low frequencies in patients with HNC, while HSV DNA was absent. These findings underline the need for larger multi-center studies and support the consideration of routine viral screening, particularly for HPV, in specific tumor subtypes.

20 March 2026 in Cancers
Verified
Journal Article
Open access
PDF file
CSComert Sen
Comert Sen
MKMehmet Furkan Kurşun
Mehmet Furkan Kurşun
OÖOnur Özçelik
Onur Özçelik
SSSinan Seyrek
Sinan Seyrek
EEEv Ev
Ev Ev
IAIsmet Aslan
Ismet Aslan
Background/Objectives: Recent meta-analyses have established that factors such as sarcopenia, male sex, and low serum albumin significantly correlate with increased postoperative complications in head and neck surgery, with routine neck computed tomography (CT) at the third cervical vertebra (C3) serving as a practical tool for muscle mass assessment. This study aimed to confirm the prognostic value of C3-based sarcopenia and specific clinical comorbidities in predicting early postoperative complications in patients with oral squamous cell carcinoma (OSCC). Methods: A retrospective cohort study was conducted on 167 patients undergoing primary surgery for OSCC. Sarcopenia was assessed using the C3-vertebra skeletal muscle index (SMI) derived from routine preoperative neck CT scans. Clinical and surgical variables, including preoperative serum albumin levels, comorbidities, and flap reconstruction types, were evaluated. A priori multivariate logistic regression models were utilized to identify independent predictors of surgical site and pulmonary and total complications (Clavien–Dindo classification) within 30 days. Results: The overall complication rate was 51%. Multivariate analysis revealed that sarcopenia (aOR: 3.26; 95% CI: 1.11–9.56), male sex (aOR: 3.48; 95% CI: 1.11–10.85), coronary artery disease (CAD) (aOR: 4.30; 95% CI: 1.21–15.36), and free-flap reconstruction (aOR: 15.06; 95% CI: 2.47–92.01) were robust independent predictors of total complications. Male sex (aOR: 4.17; 95% CI: 1.51–11.58) and preoperative hypoalbuminemia (<3.5 g/dL) (aOR: 3.43; 95% CI: 1.20–9.82) were independent predictors of surgical site complications, while regional flap reconstruction was independently associated with pulmonary complications (aOR: 5.97; 95% CI: 1.38–25.97). Conclusions: Sarcopenia, male sex, CAD, and flap reconstruction type are strong independent predictors of postoperative morbidity in OSCC. These findings advocate for “opportunistic screening” of muscle mass via routine preoperative neck CT, alongside rigorous cardiovascular profiling, to identify high-risk phenotypes for targeted perioperative optimization.

19 September 2023 in Environmental and Molecular Mutagenesis
Verified
Journal Article
Closed access
BEBaris Ertugrul
Baris Ertugrul
AMAmal Mohammed
Amal Mohammed
GKGoksu Kasarci
Goksu Kasarci
SBSinem Bireller
Sinem Bireller
EEEv Ev
Ev Ev
BCBedia Cakmakoglu
Bedia Cakmakoglu

20 March 2024 in American Journal of Otolaryngology
Verified
Journal Article
Closed access
CSComert Sen
Comert Sen
EEEv Ev
Ev Ev
EYEren Yilmaz
Eren Yilmaz
SSSaid Sonmez
Said Sonmez
MÇMehmet Çelik
Mehmet Çelik
KOKadir Serkan Orhan
Kadir Serkan Orhan