1. Initiation and elongation factor co-expression correlates with recurrence and survival in epithelial ovarian cancerMonika Sobočan, Daniela Brunialti, S Sprung, Christoph Schatz, Jure Knez, Rajko Kavalar, Iztok Takač, Johannes Haybaeck, 2022, izvirni znanstveni članek Opis: High grade epithelial ovarian cancer (EOC) represents a diagnostic and therapeutic challenge due to its aggressive features and short recurrence free survival (RFS) after primary treatment. Novel targets to inform our understanding of the EOC carcinogenesis in the translational machinery can provide us with independent prognostic markers and provide drugable targets. We have identified candidate eukaryotic initiation factors (eIF) and eukaryotic elongation factors (eEF) in the translational machinery for differential expression in EOC through in-silico analysis. We present the analysis of 150 ovarian tissue microarray (TMA) samples on the expression of the translational markers eIF2α, eIF2G, eIF5 (eIF5A and eIF5B), eIF6 and eEF1A1. All translational markers were differentially expressed among non-neoplastic ovarian samples and tumour samples (borderline tumours and EOC). In EOC, expression of eIF5A was found to be significantly correlated with recurrence free survival (RFS) and expression of eIF2G and eEF1A1 with overall survival (OS). Expression correlation among factor subunits showed that the correlation of eEF1A1, eIF2G, EIF2α and eIF5A were significantly interconnected. eIF5A was also correlated with eIF5B and eIF6. Our study demonstrates that EOCs have different translational profile compared to benign ovarian tissue and that eIF5A is a central dysregulated factor of the translation machinery. Ključne besede: epithelial ovarian cancer, initiation and elongation factor, translational markers Objavljeno v DKUM: 12.12.2024; Ogledov: 0; Prenosov: 2 Celotno besedilo (1,70 MB) Gradivo ima več datotek! Več... |
2. Translational regulation in hepatocellular carcinogenesisSuzana Bračič Tomažič, Christoph Schatz, Johannes Haybaeck, 2021, pregledni znanstveni članek Opis: The mortality of hepatocellular carcinoma (HCC) is distributed unevenly worldwide. One of the major causes is hepatitis B or hepatitis C virus infection and the development and progression of liver cirrhosis. The carcinogenesis of HCC is among others regulated via the mTOR (mechanistic target of rapamycin) signaling pathway and represents a possible method of targeted treatment. The aim of our article was to address the most recent clinical advances and findings of basic studies on the mTOR signaling pathway and the involved factors. Risk factors play a key role in dysregulation of the signaling pathway, where both mTORCs are upregulated and protein synthesis is altered. eIFs and, to a lesser extent, eEFs play an essential role in this process. Whether the factor will be upregulated or downregulated, among others, depends on hepatitis B/C virus infection. The amount of a particular factor in a patient sample lets us know whether HCC recurrence will occur, what is the likelihood of chemoresistance, and what outcome is predicted for patients with an increased value. Our analysis shows that in addition to mTOR, eIF3, eIF4, and eIF5 play an important role, as they can serve as biomarkers for non- and virus-related HCC. Ključne besede: mTOR, virus related HCC, non-virus related HCC, cancer, translation initiation, liver Objavljeno v DKUM: 18.10.2024; Ogledov: 0; Prenosov: 2 Celotno besedilo (4,21 MB) Gradivo ima več datotek! Več... |
3. Autolysis affects the iron cargo of ferritins in neurons and glial cells at different rates in the human brainSowmya Sunkara, Snježana Radulović, Saška Lipovšek Delakorda, Christoph Birkl, Stefan Eggenreich, Anna Maria Birkl-Toeglhofer, Maximilian Schinagl, Daniel Funk, Michael Stöger-Pollach, Johannes Haybaeck, Walter Gössler, Stefan Ropele, Gerd Leitinger, 2023, izvirni znanstveni članek Opis: Iron is known to accumulate in neurological disorders, so a careful balance of the iron concentration is essential for healthy brain functioning. An imbalance in iron homeostasis could arise due to the dysfunction of proteins involved in iron homeostasis. Here, we focus on ferritin—the primary iron storage protein of the brain. In this study, we aimed to improve a method to measure ferritin-bound iron in the human post-mortem brain, and to discern its distribution in particular cell types and brain regions. Though it is known that glial cells and neurons differ in their ferritin concentration, the change in the number and distribution of iron-filled ferritin cores between different cell types during autolysis has not been revealed yet. Here, we show the cellular and region-wide distribution of ferritin in the human brain using state-of-the-art analytical electron microscopy. We validated the concentration of iron-filled ferritin cores to the absolute iron concentration measured by quantitative MRI and inductively coupled plasma mass spectrometry. We show that ferritins lose iron from their cores with the progression of autolysis whereas the overall iron concentrations were unaffected. Although the highest concentration of ferritin was found in glial cells, as the total ferritin concentration increased in a patient, ferritin accumulated more in neurons than in glial cells. Summed up, our findings point out the unique behaviour of neurons in storing iron during autolysis and explain the differences between the absolute iron concentrations and iron-filled ferritin in a cell-type-dependent manner in the human brain. Ključne besede: ferritin, human brain, energy-filtered transmission electron microscopy, quantitative magnetic resonance imaging, autolysis Objavljeno v DKUM: 20.03.2024; Ogledov: 228; Prenosov: 25 Celotno besedilo (2,73 MB) Gradivo ima več datotek! Več... |
4. Translacijski nadzor biologije raka jajčnikovMonika Sobočan, 2023, doktorska disertacija Opis: Rak jajčnikov (OC) se uvršča na peto mesto med vzroki za smrt žensk po vsem svetu. Razumevanje zapletenosti različnih histoloških podtipov je ključno za usmerjeno personalizirano zdravljenje bolezni. Epitelijski rak jajčnikov (EOC) je agresiven in ima omejeno preživetje brez ponovitve (RFS) po primarnem zdravljenju. Raziskovanje novih tarč za razumevanje karcinogeneze EOC v procesu translacije lahko omogoči prepoznavo novih, neodvisnih prognostičnih označevalcev in terapevtske cilje.
Metode: Po in silico analizi evkariotskih faktorjev iniciacije in elongacije (eIF in eEF) so bili vzorci tkiva jajčnika (neoplastični, ne-neoplastični) pripravljeni s pomočjo tehnike tkivnih mikromrež (TMA). Nato so vzorci bili obarvani z imunohistokemičnemi barvami za translacijske označevalce. Intenzivnost/obseg barvanja je bil analiziran glede na parametre RFS in celokupnega preživetja po zdravljenju.
Rezultati: Opazili smo statistično pomembno razliko v izraženosti translacijskih označevalcev med ne-neoplastičnimi in tumorskimi vzorci (mejni tumorji, EOC). Zlasti je eIF5A pomembno koreliral z RFS; eIF2G in eEF1A1 sta korelirala s celotnim preživetjem (OS) pri EOC. eIF5A je kazal povezave z eIF5B in eIF6, kar nakazuje njegovo osrednjo vlogo pri disfunkciji translacijskega mehanizma pri EOC.
Zaključek: Raziskava poudarja različen translacijski profil EOC v primerjavi z benignim tkivom jajčnikov. eIF5A se kaže kot ključen pri nenormalnem translacijskem mehanizmu EOC, kar bi lahko služilo kot prognostični označevalec in terapevtski cilj. Ključne besede: rak jajčnikov, evkariotski iniciacijski faktorji, evkariontski elongacijski faktorji Objavljeno v DKUM: 02.10.2023; Ogledov: 433; Prenosov: 53 Celotno besedilo (910,32 KB) |