DNA BREAKS AND REPAIR IN LYMPHOCYTES AS A DIAGNOSTIC MARKER
 IN PATIENTS WITH GASTRIC CANCER

Abstract

Relevance: Timely detection of foci of double-strand DNA breaks with subsequent initiation of the repair mechanism plays a crucial role
 in the overall response to DNA damage. Untimely resolution of double-strand DNA breaks and disruptions in the repair pathway constitute
 a fundamental mechanism in cancer development and progression. A search for biomarkers is needed to identify foci of double-strand DNA
 breaks and achieve a better outcome of targeted therapy.
 The study aimed to identify comparative differences in double-strand breaks and DNA repair activity in γ-H2AX and 53BP1 parameters in
 conditionally healthy individuals and patients with gastric cancer.
 Methods: Analysis of focal points of γ-H2AX, 53BP1 with lymphocyte parameters using the automated AKLIDES® system in gastric cancer
 patients (n=30) and conditionally healthy individuals (n=30).
 Results: Statistically significant differences were found between conditionally healthy individuals and patients with gastric cancer in
 γ-H2AX parameters: ‘Total number of breaks’ (p=0.001), ‘Number of nuclei with break foci’ (p=0.015), ‘Average number of breaks per cell’
 (p=0.016), ‘Mean value of all break foci per cell’ (p=0.001), and in 53BP1 parameters: ‘Number of nuclei with repair foci’ (p=0.001), ‘Mean
 intensity of repair fluorescence in arbitrary units’ (p=0.001), ‘Mean number of repairs per cell’ (p=0.001), and ‘Damaged cells with low
 fluorescence intensity’ (p=0.019).
 Conclusion: Biomarkers of double-strand DNA breaks with repair activity (γ-H2AX, 53BP1) have clinical significance, contributing to the
 development of targeted medicine in oncology.