bloodjourГематология и трансфузиологияRussian journal of hematology and transfusiology0234-57302411-3042ООО Издательский дом «Практика»10.35754/0234-5730-2023-68-2-182-194bloodjour-454Research ArticleОРИГИНАЛЬНЫЕ СТАТЬИORIGINAL ARTICLESОценка относительной аллельной нагрузки мутаций устойчивости к ибрутинибу в гене ВТК методом аллель-специфичной ПЦР у больных с прогрессией хронического лимфолейкозаEvaluation of the relative allelic load of mutations of resistance to ibrutinib in the BTK gene by allele-specific PCR in patients with progression of CLLhttps://orcid.org/0000-0003-0422-6608ЛикольдЕ. Б.LikoldE. B.

Ликольд Екатерина Борисовна, научный сотрудник лаборатории молекулярной гематологии

125167, Москва

Ekaterina B. Likold, Researcher, Department of Molecular Hematology

125167, Moscow

ekaterina_likold@mail.ruhttps://orcid.org/0000-0002-6253-3334БидерманБ. В.BidermanB. V.

Бидерман Белла Вениаминовна, кандидат биологических наук, старший научный сотрудник лаборатории молекулярной гематологии

125167, Москва

Bella V. Biderman, Cand. Sci. (Biol.), Senior Researcher, Department of Molecular Hematology

125167, Moscow

https://orcid.org/0000-0002-8763-246XФевралеваИ. С.FevralevaI. S.

Февралева Ирина Серафимовна, кандидат биологических наук, ведущий научный сотрудник лаборатории молекулярной гематологии

125167, Москва

Irina S. Fevraleva, Cand. Sci. (Biol.), Leading Researcher, Department of Molecular Hematology

125167, Moscow

https://orcid.org/0000-0002-7036-9968СеверинаН. А.SeverinaN. A.

Северина Наталья Александровна, кандидат биологических наук, старший научный сотрудник лаборатории молекулярной гематологии

125167, Москва

Nataliya  A.  Severina, Cand.  Sci.  (Biol.), Senior Researcher, Department of Molecular Hematology

125167, Moscow

https://orcid.org/0000-0002-3866-4510ДмитриеваЕ. А.DmitrievaE. A.

Дмитриева Елена Александровна, гематолог

125284, Москва

 Elena A. Dmitrieva, Hematologist

125284, Moscow

https://orcid.org/0000-0001-8461-5421ПетренкоА. А.PetrenkoA. A.

Петренко Андрей Анатольевич, гематолог; аспирант кафедры гематологии и трансфузиологии

125284, Москва; 125993, Москва

 Andrii A. Petrenko, Hematologist; Postgraduate

125284, Moscow; 125993, Moscow

https://orcid.org/0000-0002-2490-1263НикитинЕ. А.NikitinE. A.

Никитин Евгений Александрович, доктор медицинских наук, профессор, заведующий дневным стационаром гематологии, онкологии и химиотерапии городского гематологического центра;заведующий кафедрой гематологии и трансфузиологии им. акад. И.А. Кассирского и А.И. Воробьева

125284, Москва; 125993, Москва

 Eugene A. Nikitin, Dr. Sci. (Med.), Professor, Head of the Day Hospital of Hematology, Oncology and Chemotherapy of the City Hematological Center; Head of the Department of Hematology and Transfusiology

125284, Moscow; 125993, Moscow

https://orcid.org/0000-0001-9463-9187СудариковА. Б.SudarikovA. B.

Судариков Андрей Борисович, доктор биологических наук, заведующий лабораторией молекулярной гематологии

125167, Москва

Andrey B. Sudarikov, Dr. Sci. (Biol.), Head of Department of Molecular Hematology

125167, Moscow

ФГБУ «Национальный медицинский исследовательский центр гематологии» Министерства здравоохранения Российской ФедерацииРоссияNational Medical Research Center for HematologyRussian FederationГБУЗ «Городская клиническая больница им. С.П. Боткина» Департамента здравоохранения г. МосквыРоссияBotkin City Clinical Hospital of the Moscow Health DepartmentRussian FederationГБУЗ «Городская клиническая больница им. С.П. Боткина» Департамента здравоохранения г. Москвы; ФГБОУ ДПО «Российская медицинская академия непрерывного профессионального образования» Министерства здравоохранения Российской ФедерацииРоссияBotkin City Clinical Hospital of the Moscow Health Department; Russian Medical Academy of Continuous Professional Education of the Ministry of Healthcare of the Russian FederationRussian Federation202318072023682182194Copyright © Ликольд Е.Б., Бидерман Б.В., Февралева И.С., Северина Н.А., Дмитриева Е.А., Петренко А.А., Никитин Е.А., Судариков А.Б., 20232023Ликольд Е.Б., Бидерман Б.В., Февралева И.С., Северина Н.А., Дмитриева Е.А., Петренко А.А., Никитин Е.А., Судариков А.Б.Likold E.B., Biderman B.V., Fevraleva I.S., Severina N.A., Dmitrieva E.A., Petrenko A.A., Nikitin E.A., Sudarikov A.B.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.htjournal.ru/jour/article/view/454Введение

Введение. Ибрутиниб является эффективным препаратом для лечения рецидивирующего, рефрактерного хронического лимфолейкоза (ХЛЛ). У большей части больных ХЛЛ ибрутиниб вызывает стойкие ремиссии, однако у части больных происходит прогрессия заболевания. Рефрактерность к ибрутинибу в большинстве случаев связана с мутацией С481S, что соответствует заменам c.1441Т>А и c.1442G>C в гене BTK, однако встречаются и другие варианты мутаций гена в этом положении.

Цель — оценить относительную аллельную нагрузку мутаций устойчивости к ибрутинибу в гене ВТК у больных с прогрессией ХЛЛ при помощи разработанной тест-системы на основе аллель-специфичной полимеразной цепной реакции (АС-ПЦР) в режиме реального времени.

Материалы и методы

Материалы и методы. В исследование был включен материал от 102 больных ХЛЛ: 39 больных ХЛЛ с прогрессией заболевания на фоне терапии ибрутинибом, 24 больных с прогрессией после терапии по протоколам «FCR/ FCR-lite», 38 больных ХЛЛ до начала лечения. Группа контроля включала в себя 118 больных неопухолевыми гематологическими заболеваниями.

Результаты

Результаты. С помощью АС-ПЦР у 20 из 39 больных ХЛЛ с прогрессией на фоне терапии ибрутинибом была выявлена мутация c.1442G>C. У 2 больных была выявлена мутация c.1442G>T. У 1 больного были обнаружены одновременно две мутации: c.1441Т>А и c.1442G>C, у 1 больного — сочетание 3 мутаций: c.1442G>C, c.1442G>T и c.1442G>A. У 15 больных с прогрессией на терапии ибрутинибом мутаций в гене BTK выявлено не было. В группах больных ХЛЛ без предварительного лечения, после режимов «FCR/FCR-lite» и в контрольной группе больных неопухолевыми заболеваниями мутаций в гене BTK выявлено не было.

Заключение

Заключение. Определена относительная аллельная нагрузка мутаций устойчивости к ибрутинибу в 15-м экзоне гена ВТК у больных с прогрессией ХЛЛ с помощью разработанной тест-системы на основе АС-ПЦР в режиме реального времени. У 50 % больных наблюдалась одна мутация, у 5 % — две мутации, у 2,5 % — три мутации в гене BTK. Своевременное выявление мутаций гена BTK до клинического рецидива может быть основанием для изменения тактики лечения. Поскольку клинические проявления устойчивости к ибрутинибу проявляются в среднем через 1–2 года, предлагается проводить мониторинг мутаций и определение относительной аллельной нагрузки каждые 3 месяца у больных ХЛЛ до рецидива при лечении ибрутинибом.

Introduction

Introduction. Currently, Ibrutinib is one of the most effective drugs for relapsed and refractory chronic lymphocytic leukemia treatment. In most patients with CLL, ibrutinib causes persistent remissions, but in some patients the disease progresses. Ibrutinib resistance in most cases is associated with the C481S mutation, which corresponds to the c.1441T>A and c.1442G>C substitutions in the BTK gene, however, other variants also exist.

Aim — to evaluate variable allele fraction of the BTK gene mutations in patients with relapsed chronic lymphocytic leukemia using the in-house allele-specific real-time PCR test.

Materials and methods

Materials and methods. The study included material from 102 cases: 39 CLL patients with disease progression on ibrutinib therapy, 24 CLL patients with disease progression on the FCR/FCR-lite protocols, and 38 CLL treatment-naive patients. The control group included 118 patients with non-neoplastic hematological diseases.

Results

Results. Using in-house using AS-PCR, we detected the c.1442G>C mutation in 20 out of 39 CLL patients with progression on ibrutinib therapy. Mutation c.1442G>T was detected in 2 patients. In a single patient, two mutations were detected simultaneously: c.1441T>A and c.1442G>C. Another single patient had a combination of three mutations: c.1442G>C, c.1442G>T and c.1442G>A. In 15 patients with progression on ibrutinib therapy, mutations in the BTK gene were not detected. In treatment-naive CLL patients, in the group treated with FCR/FCR-lite regimens, and in the control group of patients with nonneoplastic diseases, mutations in the BTK gene were not detected.

Conclusion

Conclusion. Variable allele fraction of exon 15 BTK gene mutations in the patients with CLL progression was successfully determined using in-house AS-PCR test: 50 % of patients had one mutation, 5 % had two mutations, and 2.5 % had three mutations in the BTK gene. Timely detection of these mutations before clinical recurrence may facilitate effective treatment strategy. Since clinical manifestations of ibrutinib resistance appear after an average of 1–2 years, we suggest monitoring BTK mutation load every 3 months in patients with CLL before relapse during treatment with ibrutinib.

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The authors declare that there are no conflicts of interest present.