Didem Tastekin

Prof. Dr. Didem Tastekin


Research Focus & Metrics

Academic Career Length

2Years (2025-Present)

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

Representative Publications

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Verified
Journal Article
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amir monfaredanamir monfaredan
amir monfaredan
SSSena Sen
Sena Sen
NFNahideh Karimian Fathi
Nahideh Karimian Fathi
DTDidem Tastekin
Didem Tastekin
ANalavieh sadat hosseini nasab
alavieh sadat hosseini nasab
OOOral Oncul
Oral Oncul
Immunotherapy, particularly approaches that combine tumor-specific vaccines with immune checkpoint modulation, represents a promising strategy for overcoming tumor immune evasion. While most mRNA-based cancer vaccines focus solely on antigen delivery, there is a need for platforms that simultaneously enhance antigen presentation and modulate the tumor microenvironment to increase therapeutic efficacy. This study presents a novel dual-nanolipid exosome (NLE) platform that simultaneously delivers MUC1 mRNA and CTLA-4-targeted siRNA in a single system. These endogenous lipid-based nanoparticles are structurally designed to mimic exosomes and are modified with mannose to enable selective targeting to dendritic cells (DCs) via mannose receptors. The platform was evaluated both in vitro and in vivo in terms of mRNA encapsulation efficiency, nanoparticle stability, and uptake by DCs. The co-delivery platform significantly enhanced antitumor immune responses compared to monotherapies. Flow cytometry revealed a notable increase in tumor-infiltrating CD8+ T cells (p < 0.01), and ELISPOT assays showed elevated IFN-γ production upon MUC1-specific stimulation. In vivo CTL assays demonstrated enhanced MUC1-specific cytotoxicity. Combined therapy resulted in immune response enhancement compared to vaccine or CTLA-4 siRNA alone. The NLE platform exhibited favorable biodistribution and low systemic toxicity. By combining targeted delivery of dendritic cells, immune checkpoint gene silencing, and efficient antigen expression in a biomimetic nanoparticle system, this study represents a significant advance over current immunotherapy strategies. The NLE platform shows strong potential as a modular and safe approach for RNA-based cancer immunotherapy.

13 May 2025 in Cancers
Verified
Journal Article
Open access
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amir monfaredanamir monfaredan
amir monfaredan
SSSena Sen
Sena Sen
ANalavieh sadat hosseini nasab
alavieh sadat hosseini nasab
DTDidem Tastekin
Didem Tastekin
GFGhazaleh Fazli
Ghazaleh Fazli
RORidvan Seckin Ozen
Ridvan Seckin Ozen
Background/Objectives: Glioblastoma is a highly aggressive brain tumor with limited treatment options and poor prognosis. Signal Transducer and Activator of Transcription 3 (STAT3) plays a crucial role in glioblastoma progression, making it a promising therapeutic target. However, effective delivery of STAT3-silencing agents across the blood–brain barrier remains a significant challenge. This study evaluates the efficacy of Lipid Nanoparticles-EXOSOME COMPLEX STAT3-silencer treatment in reducing glioblastoma tumor growth by facilitating efficient small interfering RNA delivery and inhibiting STAT3 expression. Methods: A novel exosome-based drug delivery system was developed using NLP-EXOSOME COMPLEX nanoparticles loaded with STAT3-silencer siRNA. The therapeutic efficacy was assessed in vitro using human glioblastoma cell lines and in vivo using a glioblastoma mouse model. Tumor progression, STAT3 expression levels, and survival rates were analyzed. Results: The results demonstrated that Lipid Nanoparticles-EXOSOME COMPLEX effectively transported STAT3-silencer siRNA into glioblastoma cells, leading to significant STAT3 downregulation. This resulted in reduced tumor proliferation, increased apoptosis, and extended survival in vivo. The combination of lipid nanoparticles and exosomes provided a stable and efficient delivery mechanism with improved uptake and therapeutic efficacy. Conclusion: Lipid Nanoparticles-EXOSOME COMPLEX STAT3-silencer treatment offers a promising approach for targeted glioblastoma therapy by overcoming the blood–brain barrier limitations and enhancing STAT3 inhibition. Further research is necessary to optimize long-term efficacy, assess potential immune responses, and explore combinatory therapeutic strategies for improved patient outcomes.

Verified
Journal Article
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BCBetül Ceylaner
Betül Ceylaner
FŞFurkan Şahin
Furkan Şahin
AYAnil Yildiz
Anil Yildiz
DTDidem Tastekin
Didem Tastekin
AGAli Fuat Kaan Gok
Ali Fuat Kaan Gok
ABAhmet Baykal
Ahmet Baykal
Gastric cancer is one of the leading causes of cancer-related deaths worldwide, and due to its late-stage diagnosis, the prognosis is poor. Therefore, researching biomarkers that can be used in early diagnosis and prognostic processes is crucial. Insulin-like growth factor (IGF) signaling pathways play critical roles in cellular proliferation, apoptosis, differentiation, and tumor progression. This study investigated the biomarker potential of IGF-1, IGFBP-4, IGFBP-5, and PAPP-A in gastric cancer. Forty gastric cancer patients and forty healthy individuals were included, and protein levels in serum samples were measured using the ELISA method. The findings showed that IGF-1 levels were significantly decreased in the gastric cancer group, while IGFBP-4 levels were significantly increased. IGFBP-5 levels were also lower in gastric cancer patients. In contrast, PAPP-A levels did not differ significantly between the two groups. ROC analyses revealed that IGF-1, IGFBP-4, and IGFBP-5 have good discriminatory properties in the diagnosis of gastric cancer, while PAPP-A offers low diagnostic value. In conclusion, this study suggests that IGF pathway components, particularly IGF-1, IGFBP-4, and IGFBP-5, might be promising biomarker candidates for gastric cancer.

27 September 2025 in Diagnostics
Verified
Journal Article
Open access
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SSSena Sen
Sena Sen
MÖMerve Çiğdem Özgel
Merve Çiğdem Özgel
STSeref Bugra Tuncer
Seref Bugra Tuncer
HBHamza Ugur Bozbey
Hamza Ugur Bozbey
SKSenem Karabulut
Senem Karabulut
DTDidem Tastekin
Didem Tastekin
Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies for which there are few effective biomarkers for diagnosis, prognosis, and treatment monitoring. Given the paucity of data in the literature, this study aimed to evaluate the biomarker potential of selected miRNAs (miR-222-3p, miR-3154, miR-3945, miR-4534, and miR-4742) and their protein targets in the context of PDAC. Methods: The expression levels of miRNA candidates were quantified by real-time quantitative PCR in lymphocyte samples from 46 PDAC patients and 50 healthy controls. In silico analyses were performed to identify potential target genes and proteins. ELISA was used to measure protein expression in both groups. Statistical analyses included ROC curve analysis, linear regression, and correlation analyses. In addition, correlations between miRNA/protein expression and clinicopathologic characteristics, including survival, were investigated. Results: miR-222-3p and miR-3154 were significantly downregulated in PDAC patients compared to controls (p < 0.001). Among the dual miRNA combinations, miR-222-3p and miR-4534 showed the highest discriminatory power (AUC = 0.629, p = 0.022). The miR-222-3p expression was significantly increased in patients with a history of alcohol consumption (p = 0.02). Significant correlations were observed between miR-3154 expression and T-stage (p = 0.01) and between perineural invasion and miR-222-3p levels (p = 0.02). Survival analysis showed that high miR-3945 expression was significantly associated with shorter overall survival (p = 0.001). Elevated levels of ESR1, HCFC1, and EPC1 were significantly associated with lymphatic invasion (p < 0.05), while high KCNA1 expression correlated with shorter survival (p = 0.006), indicating its potential as a negative prognostic biomarker. Linear regression analysis revealed a significant positive correlation between miR-3945 and KCNA1 expression (β = 0.259, p = 0.038), indicating a possible regulatory interaction. A borderline correlation was also found between miR-4742 and EPC1 expression (p = 0.055). Conclusions: This study identifies several miRNAs and associated proteins with diagnostic and prognostic significance in PDAC. The results emphasize the clinical relevance of integrating multi-layered analyses of miRNA–protein interactions. The observed associations highlight the role of these molecular markers in tumor progression and patient survival and offer promising opportunities for future research and clinical application in precision oncology.