Maria Papathanassiou

Mx. Maria Papathanassiou

University of Thessaly
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

View All Publications
14 November 2022 in Current Oncology
Verified
Journal Article
Open access
PDF file
PVPanagiotis Vlachostergios
Panagiotis Vlachostergios
ITIoannis Tamposis
Ioannis Tamposis
MAMaria Anagnostou
Maria Anagnostou
MPMaria Papathanassiou
Maria Papathanassiou
LMLAMPROS MITRAKAS
LAMPROS MITRAKAS
VTVassilios Tzortzis
Vassilios Tzortzis
Background: Hypoxia is recognized as a key feature of cancer growth and is involved in various cellular processes, including proliferation, angiogenesis, and immune surveillance. Besides hypoxia-inducible factor 1-alpha (HIF-1α), which is the main mediator of hypoxia effects and can also be activated under normoxic conditions, little is known about its counterpart, HIF-2. This study focused on investigating the clinical and molecular landscape of HIF-2-altered urothelial carcinoma (UC). Methods: Publicly available next-generation sequencing (NGS) data from muscle-invasive UC cell lines and patient tumor samples from the MSK/TCGA 2020 cohort (n = 476) were interrogated for the level of expression (mRNA, protein) and presence of mutations, copy number variations, structural variants in the EPAS1 gene encoding HIF-2, and findings among various clinical (stage, grade, progression-free and overall survival) and molecular (tumor mutational burden, enriched gene expression) parameters were compared between altered and unaltered tumors. Results: 19% (7/37) of UC cell lines and 7% (27/380) of patients with muscle-invasive UC display high EPAS1 mRNA and protein expression or/and EPAS1 alterations. EPAS1-altered tumors are associated with higher stage, grade, and lymph node metastasis as well as with shorter PFS (14 vs. 51 months, q = 0.01) and OS (15 vs. 55 months, q = 0.01). EPAS1 mRNA expression is directly correlated with that of its target-genes, including VEGF, FLT1, KDR, DLL4, CDH5, ANGPT1 (q < 0.001). While there is a slightly higher tumor mutational burden in EPAS1-altered tumors (9.9 vs. 4.9 mut/Mb), they are enriched in and associated with genes promoting immune evasion, including ARID5B, SPINT1, AAK1, CLIC3, SORT1, SASH1, and FGFR3, respectively (q < 0.001). Conclusions: HIF-2-altered UC has an aggressive clinical and a distinct genomic and immunogenomic profile enriched in angiogenesis- and immune evasion-promoting genes.

15 November 2021 in Current Oncology
Verified
Journal Article
Open access
PDF file
MSMARIA SAMARA
MARIA SAMARA
MPMaria Papathanassiou
Maria Papathanassiou
IFIoanna Farmakioti
Ioanna Farmakioti
MAMaria Anagnostou
Maria Anagnostou
MSMaria Satra
Maria Satra
PVPanagiotis Vlachostergios
Panagiotis Vlachostergios
The renin-angiotensin system (RAS), besides being a major regulator of blood pressure, is also involved in tumor angiogenesis. Emerging evidence suggests a correlation between the use of pharmacologic RAS inhibitors and a delay in urothelial bladder cancer (BC) progression. However, it is unknown whether RAS gene variants may predispose to the development of BC. This study examined the association of RAS single nucleotide polymorphisms (SNPs) including AT1R rs5186, AT2R rs11091046, REN rs12750834, ANG rs4762, and ANG rs699 with the risk of developing non-invasive BC. Peripheral blood samples from 73 patients with T1 urothelial BC (66 men, seven women) and an equal number of healthy subjects (control group) were collected. The TT genotype of the REN rs12750834 SNP (OR: 2.8 [1.3–6.05], p = 0.008) and to a lesser extent the presence of the T allele (OR: 2.3 [1.2–4.48], p = 0.01) conferred a higher risk of BC. The highest risk for BC within SNP carriers of the RAS system was associated with the presence of the CC genotype (OR: 17.6 [7.5–41.35], p < 0.001) and C allele (OR: 17.7 [8.8–35.9], p < 0.001) of the ANG rs699 SNP. The presence of the AT2R rs11091046 SNP, particularly the AA genotype, was associated with a protective effect against developing BC (OR: 0.268 [0.126–057], p < 0.001). In conclusion, these results support the clinical utility of RAS gene SNPs AT2R rs11091046, REN rs12750834, and ANG rs699 in the genetic cancer risk assessment of patients and families with BC.

14 May 2021 in Current Oncology
Verified
Journal Article
Open access
PDF file
MSMARIA SAMARA
MARIA SAMARA
MPMaria Papathanassiou
Maria Papathanassiou
LMLAMPROS MITRAKAS
LAMPROS MITRAKAS
GKGeorge Koukoulis
George Koukoulis
PVPanagiotis Vlachostergios
Panagiotis Vlachostergios
VTVassilios Tzortzis
Vassilios Tzortzis
Single nucleotide polymorphisms (SNPs) in DNA repair genes may predispose to urothelial carcinoma of the bladder (UCB). This study focused on three specific SNPs in a population with high exposure to environmental carcinogens including tobacco and alcohol. A case-control study design was used to assess for presence of XPC PAT +/−, XRCC3 Thr241Met, and ERCC2 Lys751Gln DNA repair gene SNPs in peripheral blood from patients with UCB and healthy individuals. One hundred patients and equal number of healthy subjects were enrolled. The XPC PAT +/+ genotype was associated with a 2-fold increased risk of UCB (OR = 2.16; 95%CI: 1.14–4; p = 0.01). The −/+ and +/+ XPC PAT genotypes were more frequently present in patients with multiple versus single tumors (p = 0.01). No association was detected between ERCC2 Lys751Gln genotypes/alleles, and risk for developing UCB. Presence of the XRCC3 TT genotype (OR = 0.14; 95%CI:0.07–0.25; p < 0.01) and of the T allele overall (OR = 0.26; 95%CI:0.16–0.41; p < 0.01) conferred a protective effect against developing UCB. The XPC PAT −/+ and XRCC3 Thr241Met SNPs are associated with predisposition to UCB. The XPC PAT −/+ SNP is also an indicator of bladder tumor multiplicity, which might require a more individualized surveillance and treatment.