Ahmet Alptekin

Dr. Ahmet Alptekin

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

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7 December 2023 in BioMedInformatics
Verified
Journal Article
Open access
PDF file
VVVishakha Vashisht
Vishakha Vashisht
AVASHUTOSH VASHISHT
ASHUTOSH VASHISHT
AMAshis Kumar Mondal
Ashis Kumar Mondal
JFJaspreet Farmaha
Jaspreet Farmaha
AAAhmet Alptekin
Ahmet Alptekin
RKRavindra Kolhe
Ravindra Kolhe
Emerging infectious diseases (EIDs) pose an increasingly significant global burden, driven by urbanization, population explosion, global travel, changes in human behavior, and inadequate public health systems. The recent SARS-CoV-2 pandemic highlights the urgent need for innovative and robust technologies to effectively monitor newly emerging pathogens. Rapid identification, epidemiological surveillance, and transmission mitigation are crucial challenges for ensuring public health safety. Genomics has emerged as a pivotal tool in public health during pandemics, enabling the diagnosis, management, and prediction of infections, as well as the analysis and identification of cross-species interactions and the categorization of infectious agents. Recent advancements in high-throughput DNA sequencing tools have facilitated rapid and precise identification and characterization of emerging pathogens. This review article provides insights into the latest advances in various genomic techniques for pathogen detection and tracking and their applications in global outbreak surveillance. We assess methods that leverage pathogen sequences and explore the role of genomic analysis in understanding the epidemiology of newly emerged infectious diseases. Additionally, we address technical challenges and limitations, ethical and legal considerations, and highlight opportunities for integrating genomics with other surveillance approaches. By delving into the prospects and obstacles of genomics, we can gain valuable insights into its role in mitigating the threats posed by emerging pathogens and improving global preparedness in the face of future outbreaks.

8 July 2022 in Immunological Reviews
Verified
Journal Article
Closed access
AAAhmet Alptekin
Ahmet Alptekin
MPMahrima Parvin
Mahrima Parvin
HCHasanul I. Chowdhury
Hasanul I. Chowdhury
MRMohammad H. Rashid
Mohammad H. Rashid
AAAli S. Arbab
Ali S. Arbab

30 August 2021 in Cell Death & Disease
Verified
Journal Article
Open access
PDF file
YYYajie Yu
Yajie Yu
JDJane Ding
Jane Ding
SZShunqin Zhu
Shunqin Zhu
AAAhmet Alptekin
Ahmet Alptekin
ZDZheng Dong
Zheng Dong
Hanfei DingHanfei Ding
Hanfei Ding
Metabolic reprogramming is an integral part of the growth-promoting program driven by the MYC family of oncogenes. However, this reprogramming also imposes metabolic dependencies that could be exploited therapeutically. Here we report that the pyrimidine biosynthetic enzyme dihydroorotate dehydrogenase (DHODH) is an attractive therapeutic target for MYCN-amplified neuroblastoma, a childhood cancer with poor prognosis. Gene expression profiling and metabolomic analysis reveal that MYCN promotes pyrimidine nucleotide production by transcriptional upregulation of DHODH and other enzymes of the pyrimidine-synthesis pathway. Genetic and pharmacological inhibition of DHODH suppresses the proliferation and tumorigenicity of MYCN-amplified neuroblastoma cell lines. Furthermore, we obtain evidence suggesting that serum uridine is a key factor in determining the efficacy of therapeutic agents that target DHODH. In the presence of physiological concentrations of uridine, neuroblastoma cell lines are highly resistant to DHODH inhibition. This uridine-dependent resistance to DHODH inhibitors can be abrogated by dipyridamole, an FDA-approved drug that blocks nucleoside transport. Importantly, dipyridamole synergizes with DHODH inhibition to suppress neuroblastoma growth in animal models. These findings suggest that a combination of targeting DHODH and nucleoside transport is a promising strategy to overcome intrinsic resistance to DHODH-based cancer therapeutics.

23 March 2024 in Genes
Verified
Journal Article
Open access
PDF file
VGVivek Gupta
Vivek Gupta
VVVishakha Vashisht
Vishakha Vashisht
AVASHUTOSH VASHISHT
ASHUTOSH VASHISHT
AMAshis Kumar Mondal
Ashis Kumar Mondal
AAAhmet Alptekin
Ahmet Alptekin
RKRavindra Kolhe
Ravindra Kolhe
Copy number alterations (CNAs) are significant in tumor initiation and progression. Identifying these aberrations is crucial for targeted therapies and personalized cancer diagnostics. Next-generation sequencing (NGS) methods present advantages in scalability and cost-effectiveness, surpassing limitations associated with reference assemblies and probe capacities in traditional laboratory approaches. This retrospective study evaluated CNAs in 50 FFPE tumor samples (breast cancer, ovarian carcinoma, pancreatic cancer, melanoma, and prostate carcinoma) using Illumina’s TruSight Oncology 500 (TSO500) and the Affymetrix Oncoscan Molecular Inversion Probe (OS-MIP) (ThermoFisher Scientific, Waltham, MA, USA). NGS analysis with the NxClinical 6.2 software demonstrated a high sensitivity and specificity (100%) for CNA detection, with a complete concordance rate as compared to the OS-MIP. All 54 known CNAs were identified by NGS, with gains being the most prevalent (63%). Notable CNAs were observed in MYC (18%), TP53 (12%), BRAF (8%), PIK3CA, EGFR, and FGFR1 (6%) genes. The diagnostic parameters exhibited high accuracy, including a positive predictive value, negative predictive value, and overall diagnostic accuracy. This study underscores NxClinical as a reliable software for identifying clinically relevant gene alterations using NGS TSO500, offering valuable insights for personalized cancer treatment strategies based on CNA analysis.

16 September 2022 in Cancers
Verified
Journal Article
Open access
PDF file
WDWaaqo Daddacha
Waaqo Daddacha
DMDominique Monroe
Dominique Monroe
KCKristen Carver
Kristen Carver
EUEdidiong Usoro
Edidiong Usoro
AAAhmet Alptekin
Ahmet Alptekin
DSDaitoku Sakamuro
Daitoku Sakamuro
The current standard-of-care treatment for glioblastoma includes DNA damaging agents, γ-irradiation (IR) and temozolomide (TMZ). These treatments fail frequently and there is limited alternative strategy. Therefore, identifying a new therapeutic target is urgently needed to develop a strategy that improves the efficacy of the existing treatments. Here, we report that tumor samples from GBM patients express a high level of SAMHD1, emphasizing SAMHD1’s importance. The depletion of SAMHD1 using virus-like particles containing Vpx, VLP(+Vpx), sensitized two independent GBM cell lines (LN-229 and U-87) to veliparib, a well-established PARP inhibitor, and slowed cell growth in a dose-dependent manner. In the mouse GBM xenograft model, Vpx-mediated SAMHD1 depletion reduced tumor growth and SAMHD1 knockout (KO) improved survival. In combination with IR or TMZ, SAMHD1 KO and exposure to 50% growth inhibitory dose (gID50) of VLP(+Vpx) displayed a synergistic effect, resulting in impaired HR, and improved LN-229 cells’ sensitivity to TMZ and IR. In conclusion, our finding demonstrates that SAMHD1 promotes GBM resistance to treatment, and it is a plausible therapeutic target to improve the efficacy of TMZ and IR in GBM. Furthermore, we show that Vpx could be a potential therapeutic tool that can be utilized to deplete SAMHD1 in GBM.

25 July 2024 in Biomedicines
Verified
Journal Article
Open access
PDF file
HSHarmanpreet Singh
Harmanpreet Singh
NSNikhil Shri Sahajpal
Nikhil Shri Sahajpal
AMAshis Kumar Mondal
Ashis Kumar Mondal
SBStephanie Lynn Burke
Stephanie Lynn Burke
JFJaspreet Farmaha
Jaspreet Farmaha
RKRavindra Kolhe
Ravindra Kolhe
A glioma is a solid brain tumor which originates in the brain or brain stem area. The diagnosis of gliomas based on standard-of-care (SOC) techniques includes karyotyping, fluorescence in situ hybridization (FISH), and chromosomal microarray (CMA), for detecting the pathogenic variants and chromosomal abnormalities. But these techniques do not reveal the complete picture of genetic complexity, thus requiring an alternative technology for better characterization of these tumors. The present study aimed to evaluate the clinical performance and feasibility of using optical genome mapping (OGM) for chromosomal characterization of gliomas. Herein, we evaluated 10 cases of gliomas that were previously characterized by CMA. OGM analysis showed concordance with the results of CMA in identifying the characterized Structural Variants (SVs) in these cases. More notably, it also revealed additional clinically relevant aberrations, demonstrating a higher resolution and sensitivity. These clinically relevant SVs included cryptic translocation, and SVs which are beyond the detection capabilities of CMA. Our analysis highlights the unique capability of OGM to detect all classes of SVs within a single assay, thereby unveiling clinically significant data with a shorter turnaround time. Adopting this diagnostic tool as a standard of care for solid tumors like gliomas shows potential for improving therapeutic management, potentially leading to more personalized and timely interventions for patients.