Page 124 - SRPSKO DRUŠTVO ISTRAŽIVAČA RAKA

Serbian Association for Cancer Research SDIRSACR

P27

ABCB1 polymorphisms rs2032582 and rs1045642 in epithelial ovarian cancer pathogenesis and
progression

Emina Mališić , Jelena Milovanović , Nina Petrović , Marijana Milović-Kovačević , Ivana Boljević , Nataša Todorović-
1
1,2
1
1
1
Raković , Radmila Janković 1
1
1Institute for Oncology and Radiology of Serbia, Belgrade, Serbia
2Laboratory for Radiobiology and Molecular Genetics, “Vinča“ Institute of Nuclear Sciences-National Institute of the Republic of
Serbia, University of Belgrade, Belgrade, Serbia
Keywords: ABCB1, epithelial ovarian cancer, polymorphism

Background: The ABCB1 gene encodes for ATP-binding cassette subfamily B member 1 (ABCB1) P-glycoprotein (Pgp).
It is a transmembrane efflux pump for a broad range of xenobiotics including carcinogenic substances as well as
anticancer drugs. ABCB1 polymorphisms rs2032582 (A>C/T in exon 21) and rs1045642 (A>G in exon 26) could change
Pgp expression and cellular clearance of xenobiotics, and thus influence cancer development and clinical outcome. The
effect of these polymorphisms on epithelial ovarian cancer (EOC) onset and progression is still undefined.
Patients and Methods: The epithelial ovarian tumors (75 malignant and 24 benign) were genotyped by TaqMan allelic
discrimination real-time PCR. The association of genotypes with EOC development was evaluated by χ2 test and risk
ratio (RR) with 95% confidence interval (CI). The relationship of genotypes and haplotypes with clinicopathological
(CP) characteristics of EOC was analyzed by logistic regression. Fifty-eight patients who received taxane/carboplatine
chemotherapy were followed-up for progression-free survival (PFS). PFS between genotypes was compared by the
log-rank test.
Results: The rs2032582 CC genotype was significantly more frequent in malignant vs. benign tumors (43.5% vs. 9.1%)
compared to AA plus AC (p=0.007, RR (95%CI): 4.8 (1.2-18.4)). Also, the rs1045642 GG genotype was significantly more
frequent in malignant vs. benign tumors (36.5% vs. 12.5%) compared to AA plus AG (p=0.05, RR (95%CI): 2.9 (1.0-8.8)).
The investigated genotypes and haplotypes did not correlate with EOC CP features. In the first five years of follow-up,
the AA vs. AC plus CC rs2032582 genotypes showed a trend toward lower PFS (median 12.3 vs. 22.2 months; p=0.076).
Regarding AA vs. AG plus GG rs1045642 genotypes, the difference in PFS was significant (median 10.2 vs. 26.4 months;
p<0.001).
Conclusions: The results indicate that ABCB1 rs2032582 CC and rs1045642 GG genotypes may be risk factors for
EOC development. Furthermore, the rs2032582 AA and rs1045642 AA genotypes could be biomarkers of disease
progression. Larger cohorts are needed to confirm these findings.

Acknowledgments and funding: The study was supported by the Ministry of Science, Technological Development and
Innovation of the Republic of Serbia, Grant No. 451-03-136/2025-03/200043.

P28

Distribution of EGFR -216G/T (rs712829) polymorphism: Implications for cancer risk and
pharmacogenomics

Jasmina Obradovic1, Vladimir Jurisic2

1Department of Sciences, Institute for Information Technologies Kragujevac, University of Kragujevac, Kragujevac, Republic of
Serbia
2Faculty of Medical Sciences, University of Kragujevac, Kragujevac, Republic of Serbia

Keywords: EGFR; non-small-cell lung cancer; -216G/T polymorphism; rs712829; SNP

Background: The epidermal growth factor receptor (EGFR) gene polymorphism rs712829 has been associated with non-
small cell cancer (NSCLC) risk and drug response, with variability across populations. This study aimed to investigate the
genotype and allele distributions of rs712829 across East Asian (EAS), European (EUR), and Serbian (SRB) populations,
including an analysis of gender-based differences.

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