Louis Papageorgiou

Dr. Louis Papageorgiou

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Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

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

Representative Publications

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TZTheodora Eirini Zormpa
Theodora Eirini Zormpa
TTTrias Thireou
Trias Thireou
Apostolos BeloukasApostolos Beloukas
Apostolos Beloukas
DCDimitrios Chaniotis
Dimitrios Chaniotis
RGRebecca Golfinopoulou
Rebecca Golfinopoulou
LPLouis Papageorgiou
Louis Papageorgiou
Background: Ankylosing Spondylitis (AS) is a rare autoinflammatory disorder affecting 0.1–1.4% of the population, with increasing recognition over the past 20 years. Although the specific causes of AS remain unclear, the presence of the HLA-B27 gene is associated with increased risk, though only 1–5% of carriers develop the disease. Despite extensive research, no definitive lab tests exist, and many patients are diagnosed years after symptom onset. Methods: In the present study, in order to investigate the disease’s genetic background in correlation with autoimmune diseases, a metanalysis has been performed following PRISMA guidelines using Scopus and PubMed publications towards extracting single-nucleotide polymorphisms (SNPs) of high importance for the disease. Moreover, the polymorphisms have been annotated and analyzed using information from several databases, including PubMed, LitVar2, ClinVar, and Gene Ontology. Results: From 1940 screened titles and abstracts, 57,909 studies were selected, with 539 meeting the inclusion criteria. The genetic background of AS is described through 794 genetic variants, of which 76 SNPs are directly associated with AS (Classes A and B), predominantly located in intronic regions. ERAP1 and IL23R emerged as key genes implicated in AS, while chromosomes 1, 2, and 5 accumulated the most associated SNPs. Functional enrichment revealed strong associations with immune regulation and interleukin signaling pathways, particularly IL6 and IL10 signaling. IL-6 promotes inflammation in AS, while IL-10 tries to suppress it, acting as an anti-inflammatory cytokine. Of the 78 AS-related SNPs, 16 were unique to AS, while 66 were common to autoimmune diseases, especially rheumatoid arthritis (RA) and psoriasis (PsO), suggesting genetic overlap between these diseases. Conclusions: This study creates a comprehensive genetic map of AS-associated SNPs, highlighting key pathways and genetic overlap with autoimmune diseases. These findings contribute to understanding disease mechanisms and could guide therapeutic interventions, advancing precision medicine in AS management.

23 April 2024 in Genes
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LPLouis Papageorgiou
Louis Papageorgiou
LPLefteria Papa
Lefteria Papa
EPEleni Papakonstantinou
Eleni Papakonstantinou
Antonia Charalampos MataragkaAntonia Charalampos Mataragka
Antonia Charalampos Mataragka
KDKonstantina Dragoumani
Konstantina Dragoumani
Dimitrios P VlachakisDimitrios P Vlachakis
Dimitrios P Vlachakis
The evolutionary conserved Notch signaling pathway functions as a mediator of direct cell–cell communication between neighboring cells during development. Notch plays a crucial role in various fundamental biological processes in a wide range of tissues. Accordingly, the aberrant signaling of this pathway underlies multiple genetic pathologies such as developmental syndromes, congenital disorders, neurodegenerative diseases, and cancer. Over the last two decades, significant data have shown that the Notch signaling pathway displays a significant function in the mature brains of vertebrates and invertebrates beyond neuronal development and specification during embryonic development. Neuronal connection, synaptic plasticity, learning, and memory appear to be regulated by this pathway. Specific mutations in human Notch family proteins have been linked to several neurodegenerative diseases including Alzheimer’s disease, CADASIL, and ischemic injury. Neurodegenerative diseases are incurable disorders of the central nervous system that cause the progressive degeneration and/or death of brain nerve cells, affecting both mental function and movement (ataxia). There is currently a lot of study being conducted to better understand the molecular mechanisms by which Notch plays an essential role in the mature brain. In this study, an in silico analysis of polymorphisms and mutations in human Notch family members that lead to neurodegenerative diseases was performed in order to investigate the correlations among Notch family proteins and neurodegenerative diseases. Particular emphasis was placed on the study of mutations in the Notch3 protein and the structure analysis of the mutant Notch3 protein that leads to the manifestation of the CADASIL syndrome in order to spot possible conserved mutations and interpret the effect of these mutations in the Notch3 protein structure. Conserved mutations of cysteine residues may be candidate pharmacological targets for the potential therapy of CADASIL syndrome.

28 December 2024 in Journal of Clinical Medicine
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KHKYRIAKI HATZIAGAPIOU
KYRIAKI HATZIAGAPIOU
ASAmalia Sertedaki
Amalia Sertedaki
VDVasiliki Dermentzoglou
Vasiliki Dermentzoglou
NPNataša Čurović Popović
Nataša Čurović Popović
George I LambrouGeorge I Lambrou
George I Lambrou
SSSophia D. Sakka
Sophia D. Sakka
Background/Objectives: Kenny–Caffey syndrome 2 (KCS2) is a rare cause of hypoparathyroidism, inherited in an autosomal dominant mode, resulting from pathogenic variants of the FAM111A gene, which is implicated in intracellular pathways regulating parathormone (PTH) synthesis and skeletal and parathyroid gland development. Methods: The case of a boy is reported, presenting with the characteristic and newly identified clinical, biochemical, radiological, and genetic abnormalities of KCS2. Results: The proband had noticeable dysmorphic features, and the closure of the anterior fontanel was delayed until the age of 4 years. Biochemical evaluation at several ages revealed persistent hypocalcemia, high normal phosphorous, and inappropriately low normal PTH. To exclude other causes of short stature, the diagnostic approach revealed low levels of IGF-1, and on CNS MRI, small pituitary gland and empty sella. Nocturnal levels of growth hormone were normal. MRI also revealed bilateral symmetrical microphthalmia and torturous optic nerves. Skeletal survey was compatible with cortical thickening and medullary stenosis of the long bones. Genomic data analysis revealed a well-known pathogenic variant of the FAM111A gene (c.1706G>A, p. R569H), which is linked with KCS2 or nanophthalmos. Conclusions: KCS2, although a rare disease, should be included in the differential diagnosis of hypoparathyroidism and short stature. Understanding the association of pathogenic variants with KCS2 phenotypic variability will allow the advancement of clinical genetics and personalized long-term follow-up and will offer insights into the role of the FAM111A gene in the disease pathogenesis and normal embryogenesis of implicated tissues and organs.

29 May 2020
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LPLouis Papageorgiou
Louis Papageorgiou
EPEleni Papakonstantinou
Eleni Papakonstantinou
CSConstantinos Salis
Constantinos Salis
EPEleytheria Polychronidou
Eleytheria Polychronidou
MHMarianna Hagidimitriou
Marianna Hagidimitriou
Dimitrios P VlachakisDimitrios P Vlachakis
Dimitrios P Vlachakis

27 June 2025 in Genes
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Journal Article
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SSSofia Spanou
Sofia Spanou
AAAthena Andreou
Athena Andreou
KGKaterina Gioti
Katerina Gioti
DCDimitrios Chaniotis
Dimitrios Chaniotis
Apostolos BeloukasApostolos Beloukas
Apostolos Beloukas
TTTrias Thireou
Trias Thireou
Background: Deficiency of IL-36 Receptor Antagonist (DITRA) is a rare monogenic autoinflammatory disease, characterized by dysregulation of IL-36 signaling and phenotypically classified as a subtype of generalized pustular psoriasis. Objectives: This study aimed to explore the role of potentially coding and non-coding RNAs (ncRNAs) in the IL36RN interactome to identify putative pathogenic mechanisms, biomarkers, and therapeutic targets for DITRA. Methods: A systems biology approach was applied using the STRING database to construct the IL36RN protein–protein interaction network. Key ncRNA interactions were identified using RNAInter. The networks were visualized and analyzed with Cytoscape v3 and the CytoHubba plugin to identify central nodes and interaction hubs. Pathway enrichment analysis was then performed to determine the biological relevance of candidate ncRNAs and genes. Results: Analysis identified thirty-eight ncRNAs interacting with the IL36RN network, including six lncRNAs and thirty-two miRNAs. Of these, thirty-three were associated with key DITRA-related signaling pathways, while five remain to be validated. Additionally, seven protein-coding genes were highlighted, with three (TINCR, PLEKHA1, and HNF4A) directly implicated in biological pathways related to DITRA. Many of the identified ncRNAs have prior associations with immune-mediated diseases, including psoriasis, supporting their potential relevance in DITRA pathogenesis. Conclusions: This study provides novel insights into the ncRNA-mediated regulation of IL36RN and its network in the context of DITRA. The findings support the potential utility of specific ncRNAs and genes, such as TINCR, PLEKHA1, and HNF4A, as key genomic elements warrant further functional characterization to confirm their mechanistic roles and may inform biomarker discovery and targeted therapeutic development in DITRA.

22 February 2026 in Genes
Verified
Journal Article
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LPLouis Papageorgiou
Louis Papageorgiou
ENElena Nikolopoulou
Elena Nikolopoulou
EKEleni THEODORE Koniari
Eleni THEODORE Koniari
KHKYRIAKI HATZIAGAPIOU
KYRIAKI HATZIAGAPIOU
DCDimitrios Chaniotis
Dimitrios Chaniotis
TTTrias Thireou
Trias Thireou
Background: 22q11.2 deletion syndrome (DiGeorge Syndrome) is a rare disorder that involves a de novo hemizygous microdeletion within the 22q11.2 chromosomal locus. Individuals affected by this condition display a wide array of clinical phenotypes as well as haplotype sequences, which render understanding the genotype–phenotype relationship quite difficult. Additionally, the complex structure of the 22q11.2 low-copy repeats (LCRs), which usually inhibits sequencing efforts, has complicated the study of possible breakpoints that instigate the deletion events. In this study, 22q11.2 deletion syndrome is investigated on a genomic and phenotypic level for the purpose of determining the impact of each deletion type and identifying possible candidate breakpoints. Methods: In the present study, a systematic review combined with a secondary genomic analysis has been executed following PRISMA guidelines using PubMed and Scopus publications in order to estimate its holistic genomic map, genomic functional elements, and key genomic regions such as LCRs. A statistical content analysis of the affected chromosomal regions was also performed. Groups of functional elements with common traits were composed, and their contribution to the deletion events was investigated. Finally, the 22q11.2 repeat regions were screened for palindromic AT-rich repeats. Results: Of the 8202 unique publications studied in this work, only 65 met the inclusion criteria. The estimated genomic map of 22q11.2 deletion syndrome in the secondary genomic analysis revealed 11 distinct microdeletions occurring between eight LCRs, and a new repeat region within the CES region (CESRR), of which the LCR22A-LCR22D deletion was the most frequently reported. Last but not least, the palindromic analyses indicated eight critical groups as candidate breakpoints that potentially form four distinct patterns, and ten palindromic AT-rich repeat (PATRR) regions were identified amongst LCR22A, LCR22B, LCR22D, LCR22F and LCR22H. Conclusions: The study results validate the differentiating clinical contribution between the proximal and the distal segments. Eight novel candidate breakpoints and five new PATRRs were identified that require further study to establish their involvement in 22q11.2 microdeletion events.