Publications by Year: 2021

2021
Panoutsopoulou K, Dreyer T, Dorn J, Obermayr E, Mahner S, Gorp TV, Braicu I, Zeillinger R, Magdolen V, Avgeris M, Scorilas A. tRNAGlyGCC-Derived Internal Fragment (i-tRF-GlyGCC) in Ovarian Cancer Treatment Outcome and Progression. Cancers 2021;14(1)Abstract
Epithelial ovarian cancer (EOC) remains a highly-lethal gynecological malignancy, characterized by frequent recurrence, chemotherapy resistance and poor 5-year survival. Identifying novel predictive molecular markers remains an overdue challenge in the disease's clinical management. Herein, in silico analysis of TCGA-OV highlighted the tRNA-derived internal fragment (i-tRF-GlyGCC) among the most abundant tRFs in ovarian tumors, while target prediction and gene ontology (GO) enrichment analysis predicted its implication in key biological processes. Thereafter, i-tRF-GlyGCC levels were quantified in a screening EOC (n = 98) and an institutionally-independent serous ovarian cancer (SOC) validation cohort (n = 100, OVCAD multicenter study). Disease progression and patient death were used as clinical endpoints for the survival analysis. Internal validation was performed by bootstrap analysis and the clinical net benefit was estimated by decision curve analysis. The analysis highlighted the significant association of i-tRF-GlyGCC with advanced FIGO stages, suboptimal debulking and most importantly, with early progression and poor overall survival of EOC patients. The OVCAD validation cohort corroborated the unfavorable predictive value of i-tRF-GlyGCC in EOC. Ultimately, evaluation of i-tRF-GlyGCC with the established/clinically used prognostic markers offered superior patient risk-stratification and enhanced clinical benefit in EOC prognosis. In conclusion, i-tRF-GlyGCC assessment could aid towards personalized prognosis and support precision medicine decisions in EOC.
Papanota AM, Karousi P, Kontos CK, Artemaki PI, Liacos CI, Papadimitriou MA, Bagratuni T, Eleutherakis-Papaiakovou E, Malandrakis P, Ntanasis-Stathopoulos I, Gavriatopoulou M, Kastritis E, Avgeris M, Dimopoulos MA, Scorilas A, Terpos E. A Cancer-Related microRNA Signature Shows Biomarker Utility in Multiple Myeloma. Int J Mol Sci 2021;22(23)Abstract
Multiple myeloma (MM) is the second most common hematological malignancy, arising from terminally differentiated B cells, namely plasma cells. miRNAs are small non-coding RNAs that participate in the post-transcriptional regulation of gene expression. In this study, we investigated the role of nine miRNAs in MM. CD138+ plasma cells were selected from bone marrow aspirates from MM and smoldering MM (sMM) patients. Total RNA was extracted and in vitro polyadenylated. Next, first-strand cDNA synthesis was performed using an oligo-dT-adapter primer. For the relative quantification of the investigated miRNAs, an in-house real-time quantitative PCR (qPCR) assay was developed. A functional in silico analysis of the miRNAs was also performed. miR-16-5p and miR-155-5p expression was significantly lower in the CD138+ plasma cells of MM patients than in those of sMM patients. Furthermore, lower levels of miR-15a-5p, miR-16-5p, and miR-222-3p were observed in the CD138+ plasma cells of MM patients with osteolytic bone lesions, compared to those without. miR-125b-5p was also overexpressed in the CD138+ plasma cells of MM patients with bone disease that presented with skeletal-related events (SREs). Furthermore, lower levels of miR-223-3p were associated with significantly worse overall survival in MM patients. In conclusion, we propose a miRNA signature with putative clinical utility in MM.
Xagorari M, Marmarinos A, Kossiva L, Baka M, Doganis D, Servitzoglou M, Tsolia M, Scorilas A, Avgeris M, Gourgiotis D. Overexpression of the GR Riborepressor LncRNA GAS5 Results in Poor Treatment Response and Early Relapse in Childhood B-ALL. Cancers 2021;13(23)Abstract
Glucocorticoids (GCs) remain the cornerstone of childhood acute lymphoblastic leukemia (chALL) therapy, exerting their cytotoxic effects through binding and activating of the glucocorticoid receptor (GR). GAS5 lncRNA acts as a potent riborepressor of GR transcriptional activity, and thus targeting GAS5 in GC-treated chALL could provide further insights into GC resistance and support personalized treatment decisions. Herein, to study the clinical utility of GAS5 in chALL prognosis and chemotherapy response, GAS5 expression was quantified by RT-qPCR in bone marrow samples of chB-ALL patients at diagnosis (n = 164) and at end-of-induction (n = 109), treated with ALL-BFM protocol. Patients' relapse and death were used as clinical end-points for survival analysis. Bootstrap analysis was performed for internal validation, and decision curve analysis assessed the clinical net benefit for chALL prognosis. Our findings demonstrated the elevated GAS5 levels in blasts of chALL patients compared to controls and the significantly higher risk for short-term relapse and poor treatment outcome of patients overexpressing GAS5, independently of their clinicopathological data. The unfavorable prognostic value of GAS5 overexpression was strongly validated in the high-risk/stem-cell transplantation subgroup. Finally, multivariate models incorporating GAS5 levels resulted in superior risk stratification and clinical benefit for chALL prognostication, supporting personalized prognosis and precision medicine decisions in chALL.
Alygizakis N, Markou AN, Rousis NI, Galani A, Avgeris M, Adamopoulos PG, Scorilas A, Lianidou ES, Paraskevis D, Tsiodras S, Tsakris A, Dimopoulos MA, Thomaidis NS. Analytical methodologies for the detection of SARS-CoV-2 in wastewater: Protocols and future perspectives. Trends Analyt Chem 2021;134:116125.Abstract
In March 2020 the World Health Organization announced a pandemic outbreak. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative pathogen for the coronavirus disease-19 (COVID-19) pandemic. The authorities worldwide use clinical science to identify infected people, but this approach is not able to track all symptomatic and asymptomatic cases due to limited sampling capacity of the testing laboratories. This drawback is eliminated by the Wastewater-Based Epidemiology (WBE) approach. In this review, we summarized the peer-reviewed published literature (available as of September 28, 2020), in the field of WBE. The commonly used steps (sampling, storage, concentration, isolation, detection) of the analytical protocols were identified. The potential limitations of each stage of the protocols and good practices were discussed. Finally, new methods for the efficient detection of SARS-CoV-2 were proposed.
Avgeris M, Adamopoulos PG, Galani A, Xagorari M, Gourgiotis D, Trougakos IP, Voulgaris N, Dimopoulos MA, Thomaidis NS, Scorilas A. Novel Nested-Seq Approach for SARS-CoV-2 Real-Time Epidemiology and In-Depth Mutational Profiling in Wastewater. Int J Mol Sci 2021;22Abstract
Considering the lack of effective treatments against COVID-19, wastewater-based epidemiology (WBE) is emerging as a cost-effective approach for real-time population-wide SARS-CoV-2 monitoring. Here, we report novel molecular assays for sensitive detection and mutational/variant analysis of SARS-CoV-2 in wastewater. Highly stable regions of SARS-CoV-2 RNA were identified by RNA stability analysis and targeted for the development of novel nested PCR assays. Targeted DNA sequencing (DNA-seq) was applied for the analysis and quantification of SARS-CoV-2 mutations/variants, following hexamers-based reverse transcription and nested PCR-based amplification of targeted regions. Three-dimensional (3D) structure models were generated to examine the predicted structural modification caused by genomic variants. WBE of SARS-CoV-2 revealed to be assay dependent, and significantly improved sensitivity achieved by assay combination (94%) vs. single-assay screening (30%-60%). Targeted DNA-seq allowed the quantification of SARS-CoV-2 mutations/variants in wastewater, which agreed with COVID-19 patients' sequencing data. A mutational analysis indicated the prevalence of D614G (S) and P323L (RdRP) variants, as well as of the Beta.1.1.7/alpha variant of concern, in agreement with the frequency of Beta.1.1.7/alpha variant in clinical samples of the same period of the third pandemic wave at the national level. Our assays provide an innovative cost-effective platform for real-time monitoring and early-identification of SARS-CoV-2 variants at community/population levels.
Avgeris M, Marmarinos A, Gourgiotis D, Scorilas A. Jagged Ends of Cell-Free DNA: Rebranding Fragmentomics in Modern Liquid Biopsy Diagnostics. Clin Chem 2021;67:576-578.
Kanaki Z, Voutsina A, Markou A, Pateras IS, Potaris K, Avgeris M, Makrythanasis P, Athanasiadis EI, Vamvakaris I, Patsea E, Vachlas K, Lianidou E, Georgoulias V, Kotsakis A, Klinakis A. Generation of Non-Small Cell Lung Cancer Patient-Derived Xenografts to Study Intratumor Heterogeneity. Cancers (Basel) 2021;13Abstract
Recent advances in sequencing technologies have allowed the in-depth molecular study of tumors, even at the single cell level. Sequencing efforts have uncovered a previously unappreciated heterogeneity among tumor cells, which has been postulated to be the driving force of tumor evolution and to facilitate recurrence, metastasis, and drug resistance. In the current study, focused on early-stage operable non-small cell lung cancer, we used tumor growth in patient-derived xenograft (PDX) models in mice as a fast-forward tumor evolution process to investigate the molecular characteristics of tumor cells that grow in mice, as well as the parameters that affect the grafting efficiency. We found that squamous cell carcinomas grafted significantly more efficiently compared with adenocarcinomas. Advanced stage, patient age and primary tumor size were positively correlated with grafting. Additionally, we isolated and characterized circulating tumor cells (CTC) from patients' peripheral blood and found that the presence of CTCs expressing epithelial-to-mesenchymal (EMT) markers correlated with the grafting potential. Interestingly, exome sequencing of the PDX tumor identified genetic alterations in DNA repair and genome integrity genes that were under-represented in the human primary counterpart. In conclusion, through the generation of a PDX biobank of NSCLC, we identified the clinical and molecular properties of tumors that affected growth in mice.
Papanota AM, Tsiakanikas P, Kontos CK, Malandrakis P, Liacos CI, Ntanasis-Stathopoulos I, Kanellias N, Gavriatopoulou M, Kastritis E, Avgeris M, Dimopoulos MA, Scorilas A, Terpos E. A Molecular Signature of Circulating MicroRNA Can Predict Osteolytic Bone Disease in Multiple Myeloma. Cancers (Basel) 2021;13Abstract
BACKGROUND: Multiple myeloma bone disease (MMBD) constitutes a common and severe complication of multiple myeloma (MM), impacting the quality of life and survival. We evaluated the clinical value of a panel of 19 miRNAs associated with osteoporosis in MMBD. METHODS: miRNAs were isolated from the plasma of 62 newly diagnosed MM patients with or without MMBD. First-strand cDNA was synthesized, and relative quantification was performed using qPCR. Lastly, we carried out extensive biostatistical analysis. RESULTS: Circulating levels of let-7b-5p, miR-143-3p, miR-17-5p, miR-214-3p, and miR-335-5p were significantly higher in the blood plasma of MM patients with MMBD compared to those without. Receiver operating characteristic curve and logistic regression analyses showed that these miRNAs could accurately predict MMBD. Furthermore, a standalone multi-miRNA-based logistic regression model exhibited the best predictive potential regarding MMBD. Two of those miRNAs also have a prognostic role in MM since survival analysis indicated that lower circulating levels of both let-7b-5p and miR-335-5p were associated with significantly worse progression-free survival, independently of the established prognostic factors. CONCLUSIONS: Our study proposes a miRNA signature to facilitate MMBD diagnosis, especially in ambiguous cases. Moreover, we provide evidence of the prognostic role of let-7b-5p and miR-335-5p as non-invasive prognostic biomarkers in MM.
Pateras IS, Kotsakis A, Avgeris M, Baliou E, Kouroupakis P, Patsea E, Georgoulias V, Menez-Jamet J, Kinet JP, Kosmatopoulos K. Clinical Activity of an hTERT-Specific Cancer Vaccine (Vx-001) in "Immune Desert" NSCLC. Cancers (Basel) 2021;13Abstract
BACKGROUND: Tumors can be separated into immunogenic/hot and non-immunogenic/cold on the basis of the presence of tumor-infiltrating lymphocytes (TILs), the expression of PD-L1 and the tumor mutation burden (TMB). In immunogenic tumors, TILs become unable to control tumor growth because their activity is suppressed by different inhibitory pathways, including PD-1/PD-L1. We hypothesized that tumor vaccines may not be active in the immunosuppressive microenvironment of immunogenic/hot tumors while they could be efficient in the immune naive microenvironment of non-immunogenic/cold tumors. METHODS: The randomized phase II Vx-001-201 study investigated the effect of the Vx-001 vaccine as maintenance treatment in metastatic non-small cell lung cancer (NSCLC) patients. Biopsies from 131 (68 placebo and 63 Vx-001) patients were retrospectively analyzed for PD-L1 expression and TIL infiltration. TILs were measured as tumor-associated immune cells (TAICs), CD3-TILs, CD8-TILs and granzyme B-producing TILs (GZMB-TILs). Patients were distinguished into PD-L1(+) and PD-L1(-) and into TIL high and TIL low. FINDINGS: There was no correlation between PD-L1 expression and Vx-001 clinical activity. In contrast, Vx-001 showed a significant improvement of overall survival (OS) vs. placebo in TAIC low (21 vs. 8.1 months, p = 0.003, HR = 0.404, 95% CI 0.219-0.745), CD3-TIL low (21.6 vs. 6.6 months, p < 0.001, HR = 0.279, 95% CI 0.131-0.595), CD8-TIL low (21 vs. 6.6 months, p < 0.001; HR = 0.240, 95% CI 0.11-0.522) and GZMB-TIL low (20.7 vs. 11.1 months, p = 0.011, HR = 0.490, 95% CI 0.278-0.863). Vx-001 did not offer any clinical benefit in patients with TAIC high, CD3-TIL high, CD8-TIL high or GZMB-TIL high tumors. CD3-TIL, CD8-TIL and GZMB-TIL were independent predictive factors of Vx-001 efficacy. CONCLUSIONS: These results support the hypothesis that Vx-001 may be efficient in patients with non-immunogenic/cold but not with immunogenic/hot tumors.
Tokas T, Avgeris M, Leotsakos I, Nagele U, Gozen AS. Impact of three-dimensional vision in laparoscopic partial nephrectomy for renal tumors. Turk J Urol 2021;47:144-150.Abstract
OBJECTIVE: To compare three-dimensional (3D) with standard two-dimensional (2D) laparoscopic partial nephrectomy (LPN) with respect to intra- and postoperative outcomes. MATERIAL AND METHODS: Data from 112 patients who underwent transperitoneal LPN from 2012 to 2014 by a single experienced surgeon were collected. Sixty patients (group 1) underwent conventional 2D LPN and 52 patients (group 2) 3D LPN. Perioperative patient, procedure, and tumor data were recorded. The follow-up period was 1-5 years. RESULTS: The two groups had similar patient age (p=0.834) and body mass index (p=0.141). The total laparoscopy time (LT) was shorter in group 2 (119.0 vs. 106.0 min; p=0.009). Warm ischemia times (WITs) were also shorter in group 2 (11.5 vs. 10.0 min; p=0.032). The estimated blood loss (EBL) (350.0 vs. 250.0 mL; p<0.001) and hemoglobin (Hb) decrease (1.55 vs. 1.35 g/dL; p=0.536) were lower in the 3D LPN group. Creatinine (0 vs. 0 g/dL; p=0.610) increase and estimated glomerular filtration rate (eGFR) decrease (0 vs. 0 mL/min/1.73 m(2); p=0.553) did not demonstrate statistically significant differences. Duration of hospitalization (7 vs. 7 days; p=0.099) and complication rates (p=0.559) were similar between the two groups. CONCLUSION: The new-generation 3D laparoscope has a great impact on significant LPN intraoperative parameters, mainly LT, WIT, and EBL. Hb decrease is also in favor of 3D vision, although not dramatically altered. Therefore, 3D LPN appears to be superior to conventional 2D LPNs.