Ilona Djoric

Dr. Ilona Djoric

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Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

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

Representative Publications

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12 August 2022 in Diagnostics
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Journal Article
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JRJelena Rončević
Jelena Rončević
JMJelena Janković Miljuš
Jelena Janković Miljuš
TDTijana Išić Denčić
Tijana Išić Denčić
VBVesna Bozic
Vesna Bozic
Vladan ZivaljevicVladan Zivaljevic
Vladan Zivaljevic
IDIlona Djoric
Ilona Djoric
Papillary thyroid carcinoma represents a challenge from a prognostic standpoint. Molecular alterations responsible for PTC advancement include MMP-9 genetic promoter polymorphisms that bind transcription factors with varying degrees of affinity and, hence, constitute a predisposition for MMP-9 expression. We examined how two promoter polymorphisms (the -1562 C/T transition and -131 (CA)n tandem repeats) as well as levels of the c-Jun transcription factor and its modified form acetylated at Lys271 influence MMP-9 expression and PTC progression. A significant proportion of PTC samples were heterozygous for the (CA)n tandem repeat number, had a transcription-promoting T allele at -1562, and expressed high levels of c-Jun, acetylated c-Jun, and MMP-9 protein. The T allele at the -1562 position accompanied the elevated MMP-9 protein expression, while high acetylated c-Jun levels accompanied the high MMP-9 protein levels on mRNA. The -1562 C/T transition, MMP-9, and acetylated c-Jun were associated with the presence of extra-thyroid invasion and degree of tumor infiltration, while the T allele and acetylated c-Jun also correlated with tumor stage. We conclude that the -1562 MMP-9 polymorphism and levels of acetylated c-Jun affect PTC progression via modulation of MMP-9 levels. Genotyping the MMP-9 at -1562 and estimating the levels of MMP-9 and acetylated c-Jun in PTC may prove beneficial in identifying high-risk patients.

26 June 2023 in Cells
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Journal Article
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VJValentina Ignjatović Jocić
Valentina Ignjatović Jocić
JMJelena Janković Miljuš
Jelena Janković Miljuš
TDTijana Išić Denčić
Tijana Išić Denčić
Vladan ZivaljevicVladan Zivaljevic
Vladan Zivaljevic
STSvetislav Tatić
Svetislav Tatić
SSSonja Selemetjev
Sonja Selemetjev
Thyroid carcinomas are growing malignancies worldwide. They encompass several diagnostic categories with varying degrees of dedifferentiation. Focal adhesion kinase is involved in cellular communication and locomotion. It is regulated on a posttranscriptional level by miR-7, miR-135a, and miR-138 and on a posttranslational level by autophosphorylation at Y397 (pY397-FAK). We related regulators of FAK with histologic dedifferentiation, clinicopathological factors, and differential diagnosis in the thyroid neoplasia spectrum. We classified 82 cases into 5 groups with increasing aggressiveness: healthy tissue, follicular and classical variants of papillary thyroid carcinoma (PTC), dedifferentiated PTC, and anaplastic carcinoma. MiRs were analyzed by RT-qPCR. Protein expression of pY397-FAK was analyzed by immunohistochemistry (separately in the membrane, cytoplasm, and nuclear compartment) and Western blot. All three miRs were upregulated in healthy tissue compared to malignant, while pY397-FAK was downregulated. MiRs and pY397-FAK were not mutually correlated. MiR-135a-5p was decreasing while membranous and cytoplasmic pY397-FAK increased with dedifferentiation. Neither miR correlated with clinicopathological factors. MiR-135a-5p, miR-138-5p, and membranous and cytoplasmic pY397-FAK discriminated the follicular from the classical variant of PTC. Disturbances of FAK regulation on different levels contribute to neoplastic dedifferentiation. pY397-FAK exerts its oncogenic role in the membrane and cytoplasm. Diagnostically, miRs-135a-5p, miR-138-5p, and membranous and cytoplasmic pY397-FAK differentiated between classical and follicular PTC.

18 December 2023 in Biomedicines
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Journal Article
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SSStefana Stojanović
Stefana Stojanović
SSSonja Selemetjev
Sonja Selemetjev
IDIlona Djoric
Ilona Djoric
JMJelena Janković Miljuš
Jelena Janković Miljuš
STSvetislav Tatić
Svetislav Tatić
TDTijana Išić Denčić
Tijana Išić Denčić
In order to enhance the risk stratification of papillary thyroid carcinoma (PTC) patients, we assessed the presence of the most common mutation in PTC (BRAFV600E) with the expression profiles of long non-coding RNA activated by BRAFV600E (BANCR) and microRNAs, which share complementarity with BANCR (miR-203a-3p and miR-204-3p), and thereafter correlated it with several clinicopathological features of PTC. BRAFV600E was detected by mutant allele-specific PCR amplification. BANCR and miRs levels were determined by quantitative RT-PCR. Bioinformatic analysis was applied to determine the miRs’ targets. The expression profile of miR-203a-3p/204-3p in PTC was not affected by BRAFV600E. In the BRAFV600E-positive PTC, high expression of miR-203a-3p correlated with extrathyroidal invasion (Ei), but the patients with both high miR-203a-3p and upregulated BANCR were not at risk of Ei. In the BRAFV600E-negative PTC, low expression of miR-204-3p correlated with Ei, intraglandular dissemination and pT status (p < 0.05), and the mutual presence of low miR-204-3p and upregulated BANCR increased the occurrence of Ei. Bioinformatic analysis predicted complementary binding between miR-203a-3p/204-3p and BANCR. The co-occurrence of tested factors might influence the spreading of PTC. These findings partially describe the complicated network of interactions that may occur during the development of PTC aggressiveness, potentially providing a new approach for high-risk PTC patient selection.

22 November 2023 in Bioanalysis
Verified
Journal Article
Closed access
IDIlona Djoric
Ilona Djoric
SSSonja Selemetjev
Sonja Selemetjev
Thyroglobulin (Tg) is a large protein secreted exclusively by the thyroid gland. In a clinical setting, it is measured for the purpose of follow-up of thyroidectomy patients. However, Tg measuremen... Plain language summary Thyroglobulin (Tg) is a large protein produced only by the thyroid gland. It helps physicians follow-up with patients who have had thyroid surgery. Nevertheless, Tg autoantib...

Verified
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IDIlona Djoric
Ilona Djoric
ATAleksandra Todorović
Aleksandra Todorović
MGMarija Gnjatovic
Marija Gnjatovic
SGSnežana Golubović
Snežana Golubović
MŽMiloš Žarković
Miloš Žarković
SSSonja Selemetjev
Sonja Selemetjev
Thyroglobulin (Tg) is a reliable marker for detecting recurrence in differentiated thyroid cancer (DTC) patients, but frequently occurring Tg antibodies (TgAbs) can hinder accurate measurement. We aimed to develop a preanalytical protocol for precise Tg detection in TgAb presence using the immunoradiometric assay (IRMA) platform. This study involved forty-five patients who underwent IRMA Tg and radioimmunoassay (RIA) TgAb measurements, including two patients monitored for recurrence and one with confirmed recurrence. All three had undetectable Tg levels. We evaluated three preanalytical methods in aiming to separate Tg from TgAbs: buffer only (Protocol 1), micro-spin filters only (Protocol 2), and a combination of both (Protocol 3). All preanalytical protocols showed high concordance with the original test (r = 0.981, 0.985, 0.971, respectively, p < 0.001), regardless of TgAb values. Protocols 1 and 3 yielded higher Tg levels than the original test (p < 0.001), especially in the group with a high TgAb titer. Protocol 1 managed to detect Tg in two patients under follow up with initially unmeasurable Tg and high TgAb titers and in one confirmed recurrent case. Sample pre-processing positively influenced Tg detection in TgAb-positive cases. These preanalytical approaches show promise, but further testing with larger sample sizes and more investigated conditions is warranted.