Publications by Year: 2024

2024
Soureas K, Papadimitriou MA, Malandrakis P, Papanota AM, Adamopoulos PG, Ntanasis-Stathopoulos I, Liacos CI, Gavriatopoulou M, Sideris DC, Kastritis E, Dimopoulos MA, Scorilas A, Terpos E, Avgeris M. Small RNA-seq and clinical evaluation of tRNA-derived fragments in multiple myeloma: Loss of mitochondrial i-tRF(HisGTG) results in patients' poor treatment outcome. British Journal of Haematology 2024;204:1790-1800.Abstract
Despite the substantial progress in multiple myeloma (MM) therapy nowadays, treatment resistance and disease relapse remain major clinical hindrances. Herein, we have investigated tRNA-derived fragment (tRF) profiles in MM and precursor stages (smoldering MM/sMM; monoclonal gammopathy of undetermined significance/MGUS), aiming to unveil potential MM-related tRFs in ameliorating MM prognosis and risk stratification. Small RNA-seq was performed to profile tRFs in bone marrow CD138(+) plasma cells, revealing the significant deregulation of the mitochondrial internal tRF(HisGTG) (mt-i-tRF(HisGTG)) in MM versus sMM/MGUS. The screening cohort of the study consisted of 147 MM patients, and mt-i-tRF(HisGTG) levels were quantified by RT-qPCR. Disease progression was assessed as clinical end-point for survival analysis, while internal validation was performed by bootstrap and decision curve analyses. Screening cohort analysis highlighted the potent association of reduced mt-i-tRF(HisGTG) levels with patients' bone disease (p = 0.010), osteolysis (p = 0.023) and with significantly higher risk for short-term disease progression following first-line chemotherapy, independently of patients' clinical data (HR = 1.954; p = 0.036). Additionally, mt-i-tRF(HisGTG)-fitted multivariate models led to superior risk stratification of MM patients' treatment outcome and prognosis compared to disease-established markers. Notably, our study highlighted mt-i-tRF(HisGTG) loss as a powerful independent indicator of post-treatment progression of MM patients, leading to superior risk stratification of patients' treatment outcome.
Pilala KM, Kotronopoulos G, Levis P, Giagkos GC, Stravodimos K, Vassilacopoulou D, Scorilas A, Avgeris M. MIR145 Core Promoter Methylation in Pretreatment Cell-Free DNA: A Liquid Biopsy Tool for Muscle-Invasive Bladder Cancer Treatment Outcome. JCO Precision Oncology 2024;8:e2300414.Abstract
PURPOSE: The lack of personalized management of bladder cancer (BlCa) results in patients' lifelong post-treatment monitoring with invasive interventions, underlying the urgent need for tailored and minimally invasive health care services. On the basis of our previous findings on miR-143/145 cluster methylation in bladder tumors, we evaluated its clinical significance in pretreatment cell-free DNA (cfDNA) of patients with BlCa. MATERIALS AND METHODS: Methylation analysis was performed in our screening cohort (120 patients with BlCa; 20 age-matched healthy donors) by bisulfite-based pyrosequencing. Tumor recurrence/progression for patients with non-muscle-invasive bladder cancer, and progression and mortality for patients with muscle-invasive bladder cancer (MIBC) were used as clinical end point events in survival analysis. Bootstrap analysis was applied for internal validation of Cox regression models and decision curve analysis for assessment of clinical benefit on disease prognosis. RESULTS: Decreased methylation of MIR145 core promoter in pretreatment cfDNA was associated with short-term disease progression (multivariate Cox: hazard ratio [HR], 2.027 [95% CI, 1.157 to 3.551]; P = .010) and poor overall survival (multivariate Cox: HR, 2.098 [95% CI, 1.154 to 3.817]; P = .009) of patients with MIBC after radical cystectomy (RC). Multivariate models incorporating MIR145 promoter methylation in cfDNA with tumor stage clearly ameliorated patients' risk stratification, highlighting superior clinical benefit in MIBC prognostication. CONCLUSION: Reduced pretreatment cfDNA methylation of MIR145 core promoter was markedly correlated with increased risk for short-term progression and worse survival of patients with MIBC after RC and adjuvant therapy, supporting modern personalized and minimally invasive prognosis. Methylation profiling of MIR145 core promoter in pretreatment cfDNA could serve as a minimally invasive and independent predictor of MIBC treatment outcome and emerge as a promising marker for blood-based test in BlCa.
Papailiou S, Soldatou A, Marmarinos A, Avgeris M, Papathoma E, Sindos M, Georgantzi S, Rodolakis A, Iacovidou N, Gourgiotis D, Tsolia M. Seroprevalence of diphtheria, tetanus and pertussis antibodies and Tdap vaccination in pregnant women in Greece - A cross- sectional study. Vaccine 2024;42:126435.Abstract
OBJECTIVES: We performed a cross- sectional study in two maternity hospitals in Athens, Greece between 2017 and 2019 assessing seroprevalence and Geometric Mean Titres (GMTs) of diphtheria, pertussis and tetanus antibodies in pregnant women and recorded adherence to Greek National Immunization Program (NIP) regarding Tdap vaccination in pregnancy. METHODS: Blood samples were collected from women in labour and anti- diphtheria, tetanus and pertussis toxin IgG antibodies were measured by Elisa kits. Seropositivity was defined as anti-diphtheria and anti- tetanus toxin IgG levels >/=0.1, and anti- pertussis >50 IU/mL. Seroprevalence and GMTs were calculated according to demographic factors. Tdap vaccination before and during pregnancy was self-reported by study participants. RESULTS: We analysed 253 blood samples and paired questionnaires. Seropositivity was 57.7 % for diphtheria. The lowest rate (38.2 %) was observed in the youngest age group (
Papadimitriou MA, Pilala KM, Panoutsopoulou K, Levis P, Kotronopoulos G, Kanaki Z, Loules G, Zamanakou M, Linardoutsos D, Sideris DC, Stravodimos K, Klinakis A, Scorilas A, Avgeris M. CDKN2A copy number alteration in bladder cancer: Integrative analysis in patient-derived xenografts and cancer patients. Molecular Therapy Oncology 2024;32:200818.Abstract
Bladder cancer (BlCa) is an extensively heterogeneous disease that leads to great variability in tumor evolution scenarios and lifelong patient surveillance, emphasizing the need for modern, minimally invasive precision medicine. Here, we explored the clinical significance of copy number alterations (CNAs) in BlCa. CNA profiling was performed in 15 patient-derived xenografts (PDXs) and validated in The Cancer Genome Atlas BlCa (TCGA-BLCA; n = 408) and Lindgren et al. (n = 143) cohorts. CDKN2A copy number loss was identified as the most frequent CNA in bladder tumors, associated with reduced CDKN2A expression, tumors of a papillary phenotype, and prolonged PDX survival. The study's screening cohort consisted of 243 BlCa patients, and CDKN2A copy number was assessed in genomic DNA and cell-free DNA (cfDNA) from 217 tumors and 189 pre-treatment serum samples, respectively. CDKN2A copy number loss was correlated with superior disease-free and progression-free survival of non-muscle-invasive BlCa (NMIBC) patients. Moreover, a higher CDKN2A index (CDKN2A/LEP ratio) in pre-treatment cfDNA was associated with advanced tumor stage and grade and short-term NMIBC progression to invasive disease, while multivariate models fitted for CDKN2A index in pre-treatment cfDNA offered superior risk stratification of T1/high-grade and EORTC high-risk patients, enhancing prediction of treatment outcome. CDKN2A copy number status could serve as a minimally invasive tool to improve risk stratification and support personalized prognosis in BlCa.
Dimopoulou D, Charakida M, Marmarinos A, Karaviti D, Avgeris M, Gourgiotis D, Tsolia MN. SARS-CoV-2 Antibody Kinetics in Unvaccinated Hospitalized Children With COVID-19. Pediatr Infect Dis J 2024;43:536-542.Abstract
BACKGROUND: Antibody levels decline a few months post-acute COVID-19, but humoral memory persists in adults. Age and disease severity may affect antibody responses. This study aims to evaluate the presence and durability of antibody responses in children with COVID-19. METHODS: A prospective, single-center study, involving unvaccinated children 0-16 years of age who were hospitalized with COVID-19 between October 2020 and December 2021, was conducted. Serological testing for anti-Spike severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG and neutralizing antibodies was performed at diagnosis and at 1-, 3-, 6- and 12-months post-infection. RESULTS: A total of 65 immunocompetent children were enrolled [mean age (+/-SD): 6.7 (+/-6.4) years; males: 56.9%]. At 3 months, 40/44 (91%) children were seropositive; seropositivity persisted in 22/26 (85%) children at 6 months and in 10/12 (83%) children at 12 months. There was no evidence that age was modifying the prediction of variance of SARS-CoV-2 IgG levels. In contrast, SARS-CoV-2 IgG levels varied with time and disease severity. The association with time was non-linear, so that with increasing time there was a significant reduction in SARS-CoV-2 IgG levels [coef, 0.044 (95% confidence interval CI: 0.061-0.028), P < 0.001]. For each increment of time, the higher disease severity group was associated with 0.9 lower SARS-CoV-2 IgG levels. Everyone varied from the average effect of time with an SD of 0.01, suggesting that individuals may have different trajectories across time. CONCLUSION: Disease severity, but not age, influences antibody titers among children hospitalized with COVID-19. SARS-CoV-2 infection induces durable seroconversion in these children with detectable IgG levels at 1 year after infection.
Adamopoulos PG, Diamantopoulos MA, Boti MA, Zafeiriadou A, Galani A, Kostakis M, Markou A, Sideris DC, Avgeris M, Thomaidis NS, Scorilas A. Spike-Seq: An amplicon-based high-throughput sequencing approach for the sensitive detection and characterization of SARS-CoV-2 genetic variations in environmental samples. Sci Total Environ 2024;914:169747.Abstract
Ever since the outbreak of COVID-19 disease in Wuhan, China, different variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been identified. Wastewater-based epidemiology (WBE), an approach that has been successfully applied in numerous case studies worldwide, offers a cost-effective and rapid way for monitoring trends of SARS-Cov-2 in the community level without selection bias. Despite being a gold-standard procedure, WBE is a challenging approach due to the sample instability and the moderate efficiency of SARS-CoV-2 concentration in wastewater. In the present study, we introduce Spike-Seq, a custom amplicon-based approach for the S gene sequencing of SARS-CoV-2 in wastewater samples, which enables not only the accurate identification of the existing Spike-related genetic markers, but also the estimation of their frequency in the investigated samples. The implementation of Spike-Seq involves the combination of nested PCR-based assays that efficiently amplify the entire nucleotide sequence of the S gene and next-generation sequencing, which enables the variant detection and the estimation of their frequency. In the framework of the current work, Spike-Seq was performed to investigate the mutational profile of SARS-CoV-2 in samples from the Wastewater Treatment Plant (WWTP) of Athens, Greece, which originated from multiple timepoints, ranging from March 2021 until July 2022. Our findings demonstrate that Spike-Seq efficiently detected major genetic markers of B.1.1.7 (Alpha), B.1.617.2 (Delta) as well as B.1.1.529 (Omicron) variants in wastewater samples and provided their frequency levels, showing similar variant distributions with the published clinical data from the National Public Health organization. The presented approach can prove to be a useful tool for the detection of SARS-CoV-2 in challenging wastewater samples and the identification of the existing genetic variants of S gene.