ПРОГНОСТИЧНЕ ЗНАЧЕННЯ ЕКСПРЕСІЇ RAD51 У ЛІКУВАННІ ПРЕПАРАТАМИ ПЛАТИНИ ПАЦІЄНТОК ІЗ СЕРОЗНОЮ КАРЦИНОМОЮ ЯЄЧНИКА ВИСОКОГО СТУПЕНЯ ЗЛОЯКІСНОСТІ
Background. The search for novel markers of predictive significance is an important issue in the management of ovarian cancer (OC) patients. Recently, the expression of the RAD51 protein, involved in homologous DNA repair has been shown to be predictive of platinum chemotherapy response in OC patien...
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| Date: | 2026 |
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| Pages: | 133-138 |
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Experimental Oncology| _version_ | 1874183256592613376 |
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| author | Gordiichuk, P. Doronina, M. Ponomarova, O. Gordiichuk, M. Shapochka, D. Melnyk, D. Tereshchenko, A. |
| author_facet | Gordiichuk, P. Doronina, M. Ponomarova, O. Gordiichuk, M. Shapochka, D. Melnyk, D. Tereshchenko, A. |
| author_institution_txt_mv | [
{
"author": "P. Gordiichuk",
"institution": "Shupyk National University of Healthcare of Ukraine, Kyiv, Ukraine",
"orcid": "0000-0003-2031-8772"
},
{
"author": "M. Doronina",
"institution": "Shupyk National University of Healthcare of Ukraine, Kyiv, Ukraine",
"orcid": ""
},
{
"author": "O. Ponomarova",
"institution": "Shupyk National University of Healthcare of Ukraine, Kyiv, Ukraine",
"orcid": ""
},
{
"author": "M. Gordiichuk",
"institution": "Communal nonprofit enterprise «Kyiv City Clinical Oncology Center», Kyiv, Ukraine",
"orcid": ""
},
{
"author": "D. Shapochka",
"institution": "«Feofaniya» Clinical Hospital, Kyiv, Ukraine",
"orcid": "0000-0001-5744-7872"
},
{
"author": "D. Melnyk",
"institution": "Shupyk National University of Healthcare of Ukraine, Kyiv, Ukraine",
"orcid": ""
},
{
"author": "A. Tereshchenko",
"institution": "ESC Institute of Biology and Medicine, Kyiv, Ukraine",
"orcid": ""
}
] |
| author_orcid_str_mv | 0000-0003-2031-8772 0000-0001-5744-7872 |
| author_sort | Gordiichuk, P. |
| baseUrl_str | https://exp-oncology.com.ua/index.php/Exp/oai |
| collection | OJS |
| container_end_page | 138 |
| container_issue | 2 |
| container_start_page | 133 |
| container_title | Експериментальна онкологія |
| container_volume | 48 |
| datestamp_date | 2026-08-21T12:36:17Z |
| description | Background. The search for novel markers of predictive significance is an important issue in the management of ovarian cancer (OC) patients. Recently, the expression of the RAD51 protein, involved in homologous DNA repair has been shown to be predictive of platinum chemotherapy response in OC patients. Aim. To establish the relationship between the level of RAD51 protein expression in patients with high-grade serous ovarian carcinoma (SOC) after neoadjuvant platinum chemotherapy and the frequency of recurrence, disease progression, and relapse-free survival. Materials and Methods. RAD51 status was assessed in the archival histological material of 30 patients with SOC of stage III who received perioperative platinum-based chemotherapy. RAD51 expression was analyzed using a double-staining technique in samples containing at least 100 geminin-positive tumor cells. RAD51 status was considered positive if > 10% of geminin-positive nuclei were positive for RAD51. Results. In 16 of 30 cases, the tumor had a RAD51–positive status (homologous repair proficient, HRP), and in 14 — RAD51-negative (homologous repair deficient, HRD). We found that the risk of disease progression in patients with RAD51 HRP status was 3.42 times higher compared to patients with RAD51 HRD status (HR = 3.42; 95% CI 1.38—8.46; p = 0.008). In SOC patients with RAD51 HRP status, a significantly higher (p < 0.001) rate of disease progression over 3 to 12 months of postoperative observation compared to patients with RAD51 HRD status was detected. Conclusions. RAD51 expression is predictive for the response of highgrade SOC to platinum therapy. |
| doi_str_mv | 10.15407/exp-oncology.2026.02.133 |
| first_indexed | 2026-08-22T01:00:36Z |
| format | Article |
| fulltext |
ISSN 1812-9269. Experimental Oncology 48 (2). 2026 133
ORIGINAL CONTRIBUTION
C i t a t i o n: Gordiichuk P, Doronina M, Ponomarova O, Gordiichuk M, Shapochka D, Melnyk D, Tereshchenko A. Study
of predictive value of RAD51 expression for the effectiveness of platinum-based therapy of high-grade serous ovarian
carcinoma. Exp Oncol. 2026; 48(2): 133-138. https://doi.org/10.15407/exp-oncology.2026.02.133.
© PH “Akademperiodyka” of the NAS of Ukraine, 2026. This is an open access article under the CC BY-NC-ND license
(https://creativecommons.org/licenses/by-nc-nd/4.0/)
Ovarian cancer (OC) is associated with high mor-
bidity and mortality due to latent onset, lack of
early diagnostic biomarkers, high invasiveness, and
a tendency to develop distant metastases [1—4].
The average five-year survival rate is 40%. Approx-
imately 85%—90% of all OCs are of epithelial ori-
https://doi.org/10.15407/exp-oncology.2026.02.133
P. Gordiichuk 1, 2, *, M. Doronina 1, O. Ponomarova 1, 2,
M. Gordiichuk 1, 2, D. Shapochka 3, D. Melnyk 1, A. Tereshchenko 4
1 Shupyk National University of Healthcare of Ukraine, Kyiv, Ukraine
2 Communal nonprofit enterprise «Kyiv City Clinical Oncology Center»,
Kyiv, Ukraine
3 «Feofaniya» Clinical Hospital, Kyiv, Ukraine
4 ESC Institute of Biology and Medicine, Kyiv, Ukraine
* Correspondence: E-mail: p_gordijchuk@ukr.net
STUDY OF PREDICTIVE VALUE OF RAD51
EXPRESSION FOR THE EFFECTIVENESS
OF PLATINUM-BASED THERAPY OF HIGH-GRADE
SEROUS OVARIAN CARCINOMA
Background. The search for novel markers of predictive significance is an important issue in the management of ova
rian cancer (OC) patients. Recently, the expression of the RAD51 protein, involved in homologous DNA repair has been
shown to be predictive of platinum chemotherapy response in OC patients. Aim. To establish the relationship between
the level of RAD51 protein expression in patients with high-grade serous ovarian carcinoma (SOC) after neoadjuvant
platinum chemotherapy and the frequency of recurrence, disease progression, and relapse-free survival. Materials and
Methods. RAD51 status was assessed in the archival histological material of 30 patients with SOC of stage III who
received perioperative platinum-based chemotherapy. RAD51 expression was analyzed using a double-staining tech-
nique in samples containing at least 100 geminin-positive tumor cells. RAD51 status was considered positive if > 10%
of geminin-positive nuclei were positive for RAD51. Results. In 16 of 30 cases, the tumor had a RAD51–positive status
(homologous repair proficient, HRP), and in 14 — RAD51-negative (homologous repair deficient, HRD). We found
that the risk of disease progression in patients with RAD51 HRP status was 3.42 times higher compared to patients
with RAD51 HRD status (HR = 3.42; 95% CI 1.38—8.46; p = 0.008). In SOC patients with RAD51 HRP status, a sig-
nificantly higher (p < 0.001) rate of disease progression over 3 to 12 months of postoperative observation compared to
patients with RAD51 HRD status was detected. Conclusions. RAD51 expression is predictive for the response of high-
grade SOC to platinum therapy.
Keywords: ovarian cancer, RAD51, platinum-containing chemotherapy, potential predictor of platinum sensitivity, ho-
mologous repair system.
https://doi.org/10.15407/exp-oncology.2026.02.133
https://creativecommons.org/licenses/by-nc-nd/4.0/
https://doi.org/10.15407/exp-oncology.2026.02.133
mailto:P_Gordijchuk@ukr.net
134 ISSN 1812-9269. Experimental Oncology 48 (2). 2026
P. Gordiichuk, M. Doronina, O. Ponomarova, M. Gordiichuk, D. Shapochka, D. Melnyk, A. Tereshchenko
gin, and approximately 70% of them are poorly
differentiated serous adenocarcinoma [5—7]. The
standard of treatment consists of surgical cytore-
duction and combination therapy with platinum
and taxanes. Most women with late-stage epithe-
lial OC are diagnosed with a relapse of the disease,
which requires additional treatment [2].
Platinum-containing chemotherapy is the basic
treatment of high-grade serous ovarian carcinoma
(SOC) at different stages. Platinum compounds
induce double-stranded DNA breaks in cells du
ring their replication, which leads to the death of
cancer cells.
According to the literature, the most advanced
way to repair double-stranded DNA breaks is ho-
mologous recombination repair (HRR). It is
known that various cancers, including OC, are
characterized by a homologous repair deficiency
(HRD), leading to incorrect repair of DNA breaks
and ultimately to increased tumor sensitivity to
platinum compounds and PARP inhibitors [8, 9].
HRD is often caused by loss-of-function muta-
tions in the BRCA1, BRCA2, RAD51C, RAD51D,
or PALB2 genes, or by other factors that are still
unknown [10].
Approximately 50% of high-grade SOC cases are
associated with abnormalities in HRR, including
mutations in the BRCA genes [11—13].
Genomic testing is used to detect HRD, inclu
ding analysis of BRCA status and assessment of ge-
nomic scars, which reflect genomic instability. In
turn, genomic instability is the result of HRD [8].
A genomic scar is detected by calculating the
HRD index (HRDi) or loss of heterozygosity
(LOH) [14]. However, these assays are of high cost
and require long processing time. Most impor-
tantly, they do not reflect the current functional
HRD status of tumors [15], just past events.
Therefore, in recent years, functional HRD assays
have been developed that target one of its bio-
markers, namely, the expression of the RAD51
protein [16—18] predictive of platinum chemo-
therapy response in OC patients [19].
To date, the clinical validity of RAD51 as a bio-
marker of HRD has been confirmed [20—23]. The
RAD51 test is based on the (in)ability of the RAD51
protein to accumulate at sites of DNA double-
strand breaks [16, 20, 24, 25]. It can be performed
on formalin-fixed paraffin-embedded (FFPE) tu-
mor tissue samples and includes RAD51/geminin
co-immunofluorescence staining. The RAD51 test
is of high sensitivity for detecting pathogenic
BRCA1/2 variants [26] and high predictive power
for response to platinum [27, 28] and PARP inhib-
itor therapy [25, 29].
The aim of the study was to establish the rela-
tionship between the level of RAD51 protein ex-
pression in patients with high-grade SOC after
neoadjuvant chemotherapy and the rates of relapse,
disease progression, and relapse-free survival.
Materials and Methods
The study was performed on archival histological
material (paraffin blocks and slides) from 30 pa-
tients with high-grade SOC of stage III. The study
was reviewed and approved by the Ethics and Aca-
demic Integrity Commission of the P.L. Shupyk Na-
tional University of Health Care of Ukraine (proto-
col No. 1/2024-4 dated 01.02.2024).
All the patients received neoadjuvant chemo-
therapy (NAC) and adjuvant chemotherapy (ACT):
paclitaxel 175 mg/m2 followed by cisplatin 75—
80 mg/m2 (or carboplatin AUC 5- 6) intravenously
on day 1 every 3 weeks, with a total number of cy-
cles of 6 to 8. Information from archival inpatient
and outpatient medical records indicated that all
patients had a positive radiological response to
NAC (according to RECIST 1.1) (Table 1).
The study was performed on FFPE samples of tu-
mor tissue. 4-μm thick sections were routinely pre-
pared from paraffin blocks. Antigen retrieval and
immunostaining were performed using EnVision
(Dako, Denmark), primary RAD51 antibodies
(monoclonal anti-RAD51, clone 4C11-B4, Sigma-
Aldrich, USA), secondary antibodies to RAD51 (an-
Table 1. Clinical characteristics of patients
stratified by FIGO stage and treatment response
to NAC according to RECIST 1.1 criteria (n = 30)
FIGO
stage, n
Response
by RECIST 1.1
Average
age ± σ,
years
Median body
mass index ± σ,
kg/m2SD PR
IIIA, 4 3 1
59.4 ± 6.2 26.9 ± 3.3IIIB, 2 1 1
IIIC, 24 11 13
Notes: NAC — Neoadjuvant chemotherapy; FIGO —
International Federation of Gynecology and Obstetrics;
RECIST 1.1 — Response Evaluation Criteria for Solid
Tumors; PR — partial response; SD — stable disease.
ISSN 1812-9269. Experimental Oncology 48 (2). 2026 135
Study of Predictive Value of RAD51 Expression for the Effectiveness of Platinum-Based Therapy
ti-mouse IgG(H+L) F(ab`)2 CF568, Sigma-Aldrich,
USA), primary geminin antibodies (polyclonal anti-
GMNN, HPA049977, Sigma-Aldrich, USA), and
secondary antibodies specific for geminin antibodies
(anti-rabbit IgG(H+L) F(ab`)2 CF488A, Sigma-Al-
drich, USA). The double-staining protocol, allowing
for optimal visualization of marker co-localization
in the nuclei of tumor cells, was applied. The stained
slides were examined using a Leica DM6 fluores-
cence microscope with LUCIA software at 60x mag-
nification. The cell nuclei exhibited green and blue
staining. Green nuclei were classified as geminin-
positive, whereas blue nuclei (DAPI-stained) were
classified as geminin-negative. Firstly, nuclei positive
for geminin were counted, then RAD51 expression
was assessed in samples with at least 100 tumor cells
positive for geminin, as described in [16, 28]. On
average, 5 fields were analyzed per sample. The ana-
lyzed tissue area was standardized as a tumor region
encompassing 100 geminin-positive nuclei. In such
samples, RAD51 expression (red dots) in nuclei pos-
itive for geminin was assessed. RAD51 status was
considered positive if > 10% of geminin-positive nu-
clei were positive for RAD51.
Statistical analysis was performed using IBM SPSS
Statistics, version 29.0 (SPSS Inc., Chicago, IL, USA).
The continuous variables were presented as M ± σ
(mean ± standard deviation). The differences be-
tween the parametric variables were assessed using
the two-tailed Student’s t-test. Owing to the small
sample size, Fisher’s exact test was used to compare
categorical variables and progression rates. Survival
was estimated using the Kaplan–Meier method, and
differences between survival curves were evaluated
with the log-rank test. The risk of recurrence was
calculated using the Cox proportional hazards mod-
el and expressed as hazard ratios (HRs) with 95%
confidence intervals (CIs). A p-value < 0.05 was con-
sidered statistically significant.
Results
The tumor in 16 of 30 patients had RAD51–posi-
tive HRP status (53.33%), and in 14 — negative
HRD (46.66%) (Figs. 1, 2).
The effectiveness of ACT, depending on the
RAD51 expression, was assessed by the patient’s
overall performance status (ECOG), time to dis-
ease progression, and progression-free survival
(PFS) (Table 2).
Fig. 1. RAD51-positive nuclei in cells of high-grade SOC
Fig. 2. RAD51-negative nuclei in cells of high-grade SOC
Table 2. Clinicopathological characteristics
of patients (n = 30)
Indicator
RAD51 positive
(proficient > 10%;
n = 16)
RAD51 negative
(deficient < 10%;
n = 14)
IIIA 0 4
IIIB 1 1
IIIC 15 9
ECOG (grade)
0
1
2
4
9
3
4
9
1
PFS (months)
≤ 3
≤ 6
≤ 12
< 18
24
36
6
4
5
0
1
0
0
2
3
1
1
1
Notes: ECOG — Eastern Cooperative Oncology Group
performance status; PFS — progression-free survival.
136 ISSN 1812-9269. Experimental Oncology 48 (2). 2026
P. Gordiichuk, M. Doronina, O. Ponomarova, M. Gordiichuk, D. Shapochka, D. Melnyk, A. Tereshchenko
Among patients with RAD51-positive status, the
disease progressed up to 12 months in 93.75% of cas-
es compared to 35.7% of cases with PFS < 12 months
in patients with RAD51-negative status (p = 0.0014,
Fisher’s exact test). Moreover, among patients with
RAD51-negative status, in 42.85% of cases, no pro-
gression of the disease was evident during the ob-
servation period (36 months).
Due to a small sample size, the Cox proportion-
al hazards model was used to assess the risk of dis-
ease progression. The proportional hazards as-
sumption was formally tested using the analysis of
scaled Schoenfeld residuals (Grambsch–Therneau
test, p = 0.14), confirming the adequacy of the
model. It was found that the risk of progression in
patients with RAD51 HRP status was 3.42 times
higher compared to patients with RAD51 HRD sta-
tus (HR = 3.42; 95% CI 1.38—8.46; p = 0.008).
To assess the PFS, Kaplan–Meier curves were
plotted for both groups (Fig. 3). A log-rank test
(χ2 = 12.62, p = 0.00038) confirmed a significant
difference between the survival curves. Patients
with RAD51 HRD status had a better prognosis in
terms of RFS after receiving therapy.
Discussion
Our results indicated that in patients with high-
grade SOC of stage III with RAD51 HRP status,
despite chemotherapy, the risk of progression
was significantly higher compared to patients
with RAD51 HRD status.
We found RAD51 expression in 46.7% of our
SOC cases, which is slightly higher than the 30%—
40% reported in several other studies [16, 28, 30].
This discrepancy likely stems from varying cut-off
thresholds across the literature. Following studies
that established a >10% threshold as most accurate
[16, 28, 29], we defined positive RAD51 status
(HRP) as >10% geminin-positive nuclei and nega-
tive (HRD) as <10%. Nevertheless, different refe
rence values have also been used in other studies
(e.g., >25.89% or >35%) [16, 31]. Consequently, es-
tablishing a standardized clinical cut-off for defin-
ing RAD51 expression requires further accumula-
tion of clinical data.
Our study results have demonstrated that the
HRD functional test can predict a longer period
without tumor recurrence (HR = 0.22), which con-
firms the significant predictive value of RAD51 for
the effectiveness of the treatment with platinum
drugs. Nevertheless, our study does not fully sup-
port the suggestions [28, 31] that RAD51 foci can
predict platinum sensitivity with 100% specificity
and 100% positive predictive value.
The results show a high probability of platinum
sensitivity in SOC with low RAD51 expression lev-
els. However, it should be noted that platinum sen-
sitivity is multifactorial and also depends on drug
uptake, DNA damage signaling, nucleotide exci-
sion repair, cell cycle checkpoints, cell death path-
ways, etc. [32].
In this study, we did not find any association be-
tween RAD51 expression levels and patient age,
BMI, and disease stage, nor have we found such
data in other similar studies.
Because our study relied on archival material, we
could not assess RAD51 dynamics. Nevertheless,
IGH histological analysis offers an accessible, inex-
pensive, and highly predictive method for evalua
ting PARP inhibitor efficacy [16, 33, 34], advancing
future ovarian cancer research.
Acknowledgments
All authors express their sincere gratitude to the
Armed Forces of Ukraine, who ensure our safety
and make it possible for us to work.
Conflicts of interest/Financial
disclosures
The authors declare no conflict of interest regarding
the research, authorship, or publication of this arti-
cle. This study did not receive any financial support.
Fig. 3. Kaplan–Meier curves of PFS: Group 1 — RAD51
HRP (n = 16); Group 2 — RAD51 HRD (n = 14)
ISSN 1812-9269. Experimental Oncology 48 (2). 2026 137
Study of Predictive Value of RAD51 Expression for the Effectiveness of Platinum-Based Therapy
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Submitted: January 29, 2026
П. Гордійчук 1, 2, М. Дороніна 1 , О. Пономарьова 1, 2,
М. Гордійчук 1, 2, Д. Шапочка 3, Д. Мельник 1, А. Терещенко 4
1 Національний університет охорони здоров’я України
імені П.Л. Шупика, Київ, Україна
2 КНП «Київський міський клінічний онкологічний центр», Київ, Україна
3 Клінічна лікарня «Феофанія», Київ, Україна
4 ННЦ «Інститут біології та медицини», Київ, Україна
ПРОГНОСТИЧНЕ ЗНАЧЕННЯ ЕКСПРЕСІЇ RAD51 У ЛІКУВАННІ
ПРЕПАРАТАМИ ПЛАТИНИ ПАЦІЄНТОК ІЗ СЕРОЗНОЮ
КАРЦИНОМОЮ ЯЄЧНИКА ВИСОКОГО СТУПЕНЯ ЗЛОЯКІСНОСТІ
Вступ. Рак яєчника характеризується високим рівнем захворюваності та смертності. Висока інвазивність серозної
карциноми яєчника високого ступеня злоякісності за відсутності надійних біомаркерів призводить до пізньої
діагностики та раннього метастазування, що стає на заваді вибору ефективного медикаментозного лікування.
Для раку яєчника характерним є дефіцит системи гомологічної репарації (HRD), де RAD51 відіграє ключову роль
у її відновленні. Мета роботи — встановити зв’язок між рівнем експресії білка RAD51 у пацієнток з серозною
карциномою яєчників високого ступеня злоякісності після неоад’ювантної хіміотерапії препаратами платини
з частотою виникнення рецидиву, прогресування захворювання та безрецидивною виживаністю. Матеріали та
методи. Представлено попередні результати дослідження архівних гістологічних матеріалів 30 хворих на серозну
карциному яєчника високого ступеня злоякісності III стадії, які отримували периопераційну хіміотерапію. Статус
RAD51 оцінювався імуногістохімічно в зразках, що містили мінімум 100 пухлинних клітин, позитивних на гемі-
нін. Статус RAD51 вважався позитивним, якщо >10% гемінін-позитивних ядер були позитивні на RAD51. Резуль-
тати. У 16 з 30 пацієнток (53,33%) пухлини мали RAD51-позитивний статус HRP (із збереженою функцією гомо-
логічної рекомбінації), у 14 (46,66%) — RAD51-негативний статус HRD (із дефіцитом гомологічної рекомбінації).
Встановлено, що ризик прогресування захворювання в пацієнток зі статусом RAD51 HRP був у 3,42 раза вищим
порівняно з пацієнтами зі статусом RAD51 HRD (HR = 3,42; 95% ДІ 1,38—8,46; p = 0,008). Отримані результати
свідчать, що в пацієнток із серозною карциномою яєчників високого ступеня злоякісності III стадії зі статусом
RAD51 HRP, незважаючи на проведену хіміотерапію, спостерігалося статистично значуще (p < 0,001) підвищення
частоти прогресування захворювання в період від 3 до 12 місяців післяопераційного спостереження порівняно
з пацієнтами зі статусом RAD51 HRD. Висновок. Експресія RAD51 має вагоме прогностичне значення щодо від-
повіді хворих на серозну карциному яєчника високого ступеня злоякісності на терапію препаратами платини та
потребує проведення додаткових досліджень для рутинного застосування в клінічній практиці.
Ключові слова: рак яєчника, RAD51, платиновмісна хіміотерапія, потенційний предиктор чутливості до пла-
тини, система гомологічної репарації.
https://doi.org/10.1200/JCO.2021.39.15_suppl.5513
https://doi.org/10.1016/
https://doi.org/10.1158/0008-5472.CAN-21-2409
https://doi.org/10.1158/1078-0432.CCR-10-1027
https://doi.org/10.1158/1078-0432.CCR-10-1027
https://doi.org/10.15252/emmm.202013366
https://doi.org/10.1016/j.ijgc.2024.100031
https://doi.org/10.1038/nrd1691
https://doi.org/10.3389/fonc.2022.963728
https://doi.org/10.3389/fonc.2022.963728
https://doi.org/10.3892/ijo.2025.5771
|
| id | oai:ojs2.ex.aqua-time.com.ua:article-645 |
| institution | Experimental Oncology |
| issn | 2312-8852 |
| keywords_txt_mv | |
| language | English |
| last_indexed | 2026-08-22T01:00:36Z |
| publishDate | 2026 |
| publisher | PH Akademperiodyka |
| record_format | ojs |
| resource_txt_mv | exp-oncologycomua/ea/c054dd236e29e4b818cde2d2906988ea.pdf |
| spelling | oai:ojs2.ex.aqua-time.com.ua:article-6452026-08-21T12:36:17Z STUDY OF PREDICTIVE VALUE OF RAD51 EXPRESSION FOR THE EFFECTIVENESS OF PLATINUM-BASED THERAPY OF HIGH-GRADE SEROUS OVARIAN CARCINOMA ПРОГНОСТИЧНЕ ЗНАЧЕННЯ ЕКСПРЕСІЇ RAD51 У ЛІКУВАННІ ПРЕПАРАТАМИ ПЛАТИНИ ПАЦІЄНТОК ІЗ СЕРОЗНОЮ КАРЦИНОМОЮ ЯЄЧНИКА ВИСОКОГО СТУПЕНЯ ЗЛОЯКІСНОСТІ Gordiichuk, P. Doronina, M. Ponomarova, O. Gordiichuk, M. Shapochka, D. Melnyk, D. Tereshchenko, A. рак яєчника, RAD51, платиновмісна хіміотерапія, потенційний предиктор чутливості до платини, система гомологічної репарації ovarian cancer, RAD51, platinum-containing chemotherapy, potential predictor of platinum sensitivity, homologous repair system Background. The search for novel markers of predictive significance is an important issue in the management of ovarian cancer (OC) patients. Recently, the expression of the RAD51 protein, involved in homologous DNA repair has been shown to be predictive of platinum chemotherapy response in OC patients. Aim. To establish the relationship between the level of RAD51 protein expression in patients with high-grade serous ovarian carcinoma (SOC) after neoadjuvant platinum chemotherapy and the frequency of recurrence, disease progression, and relapse-free survival. Materials and Methods. RAD51 status was assessed in the archival histological material of 30 patients with SOC of stage III who received perioperative platinum-based chemotherapy. RAD51 expression was analyzed using a double-staining technique in samples containing at least 100 geminin-positive tumor cells. RAD51 status was considered positive if &gt; 10% of geminin-positive nuclei were positive for RAD51. Results. In 16 of 30 cases, the tumor had a RAD51–positive status (homologous repair proficient, HRP), and in 14 — RAD51-negative (homologous repair deficient, HRD). We found that the risk of disease progression in patients with RAD51 HRP status was 3.42 times higher compared to patients with RAD51 HRD status (HR = 3.42; 95% CI 1.38—8.46; p = 0.008). In SOC patients with RAD51 HRP status, a significantly higher (p &lt; 0.001) rate of disease progression over 3 to 12 months of postoperative observation compared to patients with RAD51 HRD status was detected. Conclusions. RAD51 expression is predictive for the response of highgrade SOC to platinum therapy. Вступ. Рак яєчника характеризується високим рівнем захворюваності та смертності. Висока інвазивність серозної карциноми яєчника високого ступеня злоякісності за відсутності надійних біомаркерів призводить до пізньої діагностики та раннього метастазування, що стає на заваді вибору ефективного медикаментозного лікування. Для раку яєчника характерним є дефіцит системи гомологічної репарації (HRD), де RAD51 відіграє ключову роль у її відновленні. Мета роботи — встановити зв’язок між рівнем експресії білка RAD51 у пацієнток з серозною карциномою яєчників високого ступеня злоякісності після неоад’ювантної хіміотерапії препаратами платини з частотою виникнення рецидиву, прогресування захворювання та безрецидивною виживаністю. Матеріали та методи. Представлено попередні результати дослідження архівних гістологічних матеріалів 30 хворих на серозну карциному яєчника високого ступеня злоякісності III стадії, які отримували периопераційну хіміотерапію. Статус RAD51 оцінювався імуногістохімічно в зразках, що містили мінімум 100 пухлинних клітин, позитивних на гемінін. Статус RAD51 вважався позитивним, якщо &gt;10% гемінін-позитивних ядер були позитивні на RAD51. Результати. У 16 з 30 пацієнток (53,33%) пухлини мали RAD51-позитивний статус HRP (із збереженою функцією гомологічної рекомбінації), у 14 (46,66%) — RAD51-негативний статус HRD (із дефіцитом гомологічної рекомбінації). Встановлено, що ризик прогресування захворювання в пацієнток зі статусом RAD51 HRP був у 3,42 раза вищим порівняно з пацієнтами зі статусом RAD51 HRD (HR = 3,42; 95% ДІ 1,38—8,46; p = 0,008). Отримані результати свідчать, що в пацієнток із серозною карциномою яєчників високого ступеня злоякісності III стадії зі статусом RAD51 HRP, незважаючи на проведену хіміотерапію, спостерігалося статистично значуще (p &lt; 0,001) підвищення частоти прогресування захворювання в період від 3 до 12 місяців післяопераційного спостереження порівняно з пацієнтами зі статусом RAD51 HRD. Висновок. Експресія RAD51 має вагоме прогностичне значення щодо відповіді хворих на серозну карциному яєчника високого ступеня злоякісності на терапію препаратами платини та потребує проведення додаткових досліджень для рутинного застосування в клінічній практиці. PH Akademperiodyka 2026-08-21 Article Article application/pdf https://exp-oncology.com.ua/index.php/Exp/article/view/645 10.15407/exp-oncology.2026.02.133 Experimental Oncology; Vol. 48 No. 2 (2026): Experimental Oncology; 133-138 Експериментальна онкологія; Том 48 № 2 (2026): Експериментальна онкологія; 133-138 2312-8852 1812-9269 10.15407/exp-oncology.2026.02 en https://exp-oncology.com.ua/index.php/Exp/article/view/645/473 Copyright (c) 2026 Experimental Oncology https://creativecommons.org/licenses/by-nc-nd/4.0/ |
| spellingShingle | рак яєчника RAD51 платиновмісна хіміотерапія потенційний предиктор чутливості до платини система гомологічної репарації Gordiichuk, P. Doronina, M. Ponomarova, O. Gordiichuk, M. Shapochka, D. Melnyk, D. Tereshchenko, A. ПРОГНОСТИЧНЕ ЗНАЧЕННЯ ЕКСПРЕСІЇ RAD51 У ЛІКУВАННІ ПРЕПАРАТАМИ ПЛАТИНИ ПАЦІЄНТОК ІЗ СЕРОЗНОЮ КАРЦИНОМОЮ ЯЄЧНИКА ВИСОКОГО СТУПЕНЯ ЗЛОЯКІСНОСТІ |
| title | ПРОГНОСТИЧНЕ ЗНАЧЕННЯ ЕКСПРЕСІЇ RAD51 У ЛІКУВАННІ ПРЕПАРАТАМИ ПЛАТИНИ ПАЦІЄНТОК ІЗ СЕРОЗНОЮ КАРЦИНОМОЮ ЯЄЧНИКА ВИСОКОГО СТУПЕНЯ ЗЛОЯКІСНОСТІ |
| title_alt | STUDY OF PREDICTIVE VALUE OF RAD51 EXPRESSION FOR THE EFFECTIVENESS OF PLATINUM-BASED THERAPY OF HIGH-GRADE SEROUS OVARIAN CARCINOMA |
| title_full | ПРОГНОСТИЧНЕ ЗНАЧЕННЯ ЕКСПРЕСІЇ RAD51 У ЛІКУВАННІ ПРЕПАРАТАМИ ПЛАТИНИ ПАЦІЄНТОК ІЗ СЕРОЗНОЮ КАРЦИНОМОЮ ЯЄЧНИКА ВИСОКОГО СТУПЕНЯ ЗЛОЯКІСНОСТІ |
| title_fullStr | ПРОГНОСТИЧНЕ ЗНАЧЕННЯ ЕКСПРЕСІЇ RAD51 У ЛІКУВАННІ ПРЕПАРАТАМИ ПЛАТИНИ ПАЦІЄНТОК ІЗ СЕРОЗНОЮ КАРЦИНОМОЮ ЯЄЧНИКА ВИСОКОГО СТУПЕНЯ ЗЛОЯКІСНОСТІ |
| title_full_unstemmed | ПРОГНОСТИЧНЕ ЗНАЧЕННЯ ЕКСПРЕСІЇ RAD51 У ЛІКУВАННІ ПРЕПАРАТАМИ ПЛАТИНИ ПАЦІЄНТОК ІЗ СЕРОЗНОЮ КАРЦИНОМОЮ ЯЄЧНИКА ВИСОКОГО СТУПЕНЯ ЗЛОЯКІСНОСТІ |
| title_short | ПРОГНОСТИЧНЕ ЗНАЧЕННЯ ЕКСПРЕСІЇ RAD51 У ЛІКУВАННІ ПРЕПАРАТАМИ ПЛАТИНИ ПАЦІЄНТОК ІЗ СЕРОЗНОЮ КАРЦИНОМОЮ ЯЄЧНИКА ВИСОКОГО СТУПЕНЯ ЗЛОЯКІСНОСТІ |
| title_sort | прогностичне значення експресії rad51 у лікуванні препаратами платини пацієнток із серозною карциномою яєчника високого ступеня злоякісності |
| topic | рак яєчника RAD51 платиновмісна хіміотерапія потенційний предиктор чутливості до платини система гомологічної репарації |
| topic_facet | рак яєчника RAD51 платиновмісна хіміотерапія потенційний предиктор чутливості до платини система гомологічної репарації ovarian cancer RAD51 platinum-containing chemotherapy potential predictor of platinum sensitivity homologous repair system |
| url | https://exp-oncology.com.ua/index.php/Exp/article/view/645 |
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