Tomislav Sajko

Dr. Tomislav Sajko


Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

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

Representative Publications

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Dragana FabrisDragana Fabris
Dragana Fabris
IKIvana Karmelić
Ivana Karmelić
HMHasan Muharemovic
Hasan Muharemovic
TSTomislav Sajko
Tomislav Sajko
MSMia Jurilj Sajko
Mia Jurilj Sajko
ŽVŽeljka Vukelić
Željka Vukelić
Gangliosides serve as antitumor therapy targets and aberrations in their composition strongly correlate with tumor growth and invasiveness. Anaplastic ganglioglioma is a rare, poorly characterized, malignant neuronal–glial tumor type. We present the first comparative characterization of ganglioside composition in anaplastic ganglioglioma vs. peritumoral and healthy brain tissues by combining mass spectrometry and thin-layer chromatography. Anaplastic ganglioglioma ganglioside composition was highly distinguishable from both peritumoral and healthy tissue despite having five to six times lower total content. Ten out of twelve MS-identified ganglioside classes, defined by unique glycan residues, were represented by a large number and considerable abundance of individual species with different fatty acid residues (C16–C24) in ceramide portions. The major structurally identified class was tumor-associated GD3 (>50%) with 11 species; GD3 (d18:1/24:0) being the most abundant. The dominant sphingoid base residue in ganglioside ceramides was sphingosine (d18:1), followed by eicosasphingosine (d20:1). The peritumoral tissue ganglioside composition was estimated as normal. Specific ganglioside composition and large variability of ganglioside ceramide structures determined in anaplastic ganglioglioma demonstrate realistic ganglioside expression patterns and correspond to the profile of high-grade malignancy brain tumors.

23 June 2022 in Molecules
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RIRaluca Ica
Raluca Ica
Kristina Mlinac-JerkovićKristina Mlinac-Jerković
Kristina Mlinac-Jerković
KIKatarina Ilic
Katarina Ilic
TSTomislav Sajko
Tomislav Sajko
CMCristian V. A. Munteanu
Cristian V. A. Munteanu
SBSvjetlana Bognar
Svjetlana Bognar
In this study, we developed a high-resolution tandem mass spectrometry (HR MS) approach to assess presumed changes in gangliosidome of a human hippocampus affected by temporal lobe epilepsy (TLE) in comparison with a normal hippocampus. Gangliosides, membrane glycolipids, are particularly diverse and abundant in the human brain, and participate in ion transport and modulation of neuronal excitability. Changes in structural ganglioside pattern potentially linked to TLE molecular pathogenesis have not been explored in detail. Aiming to characterize TLE-specific gangliosidome, we analyzed the native gangliosides purified from a human hippocampal tissue sample affected by TLE and a control hippocampus using HR MS. Marked differences of ganglioside expression were shown in TLE vs. control, particularly with respect to the sialylation degree of components, discovered as a characteristic feature of TLE. Another major finding is the occurrence of tetrasialofucogangliosides in TLE and species modified by either O-acetylation or CH3COO−. Structural analysis by higher-energy collisional dissociation (HCD) MS/MS gave rise to fragmentation patterns implying that the GQ1b (d18:1/18:0) isomer is specifically associated with TLE. Further investigation in a larger sample is needed in order to confirm the discovery of ganglioside structures specifically expressed in human TLE and to provide information on the probable role of gangliosides in the molecular events underlying seizures.

2 July 2015 in Acta Neurochirurgica
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TSTomislav Sajko
Tomislav Sajko
ŽGŽivko Gnjidić
Živko Gnjidić
NSNikolina Sesar
Nikolina Sesar
MMMasa Malenica
Masa Malenica

2 August 2024 in Biomedicines
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IKIvana Karmelić
Ivana Karmelić
IRIvana Rubić
Ivana Rubić
KSKatarina Starcevic
Katarina Starcevic
DODavid Ozretic
David Ozretic
ZPZdravka Poljaković
Zdravka Poljaković
Dragana FabrisDragana Fabris
Dragana Fabris
Ischemic stroke is one of the leading causes of death and permanent disability in the world. Rapid diagnosis and intervention are crucial for reducing its consequences on individuals and societies. Therefore, identifying reliable biomarkers for early detection, prognostics, and therapy can facilitate the early prediction and prevention of stroke. Metabolomics has been shown as a promising tool for biomarker discovery since many post-ischemic metabolites can be found in the plasma or serum of the patient. In this research, we performed a comparative targeted metabolomic analysis of stroke thrombi, stroke patient serums, and healthy control serums in order to determine the alteration in the patients’ metabolomes, which might serve as biomarkers for early prediction or stroke prevention. The most statistically altered metabolites characterized in the patient serums compared with the control serums were glutamate and serotonin, followed by phospholipids and triacylglycerols. In stroke thrombi compared with the patients’ serums, the most significantly altered metabolites were classified as lipids, with choline-containing phospholipids and sphingomyelins having the highest discriminatory score. The results of this preliminary study could help in understanding the roles of different metabolic changes that occur during thrombosis and cerebral ischemia and possibly suggest new metabolic biomarkers for ischemic stroke.

1 January 2012 in Translational Neuroscience
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HČHrvoje Čupić
Hrvoje Čupić
TSTomislav Sajko
Tomislav Sajko
NSNikolina Sesar
Nikolina Sesar
MIMihovil Ivica
Mihovil Ivica
LPLeo Pažanin
Leo Pažanin
Gangliogliomas are well differentiated and slowly growing neuroepithelial tumors composed of neoplastic ganglion cells and neoplastic glial cells corresponding mostly to the World Health Organization grade I tumors. However, some of these tumors disclose histologically more malignant glial component and correspond to grade II or grade III tumors. We report a case of left temporal lobe tumor in a 42-year-old woman fulfilling the diagnostic criteria for atypical (grade II) ganglioglioma with high Ki-67 proliferation index and p53 immunoreactive tumor cells. In spite of gross total removal of the tumor, it recurred eight months after surgery. Histopathological examination of the recurrent tumor revealed that it had undergone malignant transformation into a glioblastoma. This case indicates that gangliogliomas with high Ki-67 proliferating index and p53 immunoreactivity should be carefully monitored for recurrence and malignant progression regardless of their morphological grading and seemingly total surgical removal.