DIAGNOSTIC AND PROGNOSTIC VALUE OF TUMOR-ASSOCIATED miRNA-21, -125b AND -221 IN PATIENTS WITH THE MOST COMMON HORMONE-DEPENDENT MALIGNANCIES

Lukianova N.Yu.¹, Borikun T.V.¹, Zadvornyi T.V.¹, Yalovenko T.M.¹, Bazas V.M.², Kliusov O.M.², Stakhovsky E.O.³, Chekhun V.F.¹

• ¹R.E. Kavetsky Institute of experimental pathology, oncology and radiobiology of NAS of Ukraine, Kyiv, Ukraine
• ²Kyiv City Clinical Oncology Center, Kyiv, Ukraine
• ³National Cancer Institute, Kyiv, Ukraine

One of the current areas of fundamental oncology in recent years is the study of epigenetic disorders in the development and progression of hormone-dependent malignancies, which include breast cancer (BC) and prostate cancer (PCa). Aim: to investigate the expression of miRNA-21, -125b and -221 in tumor tissue of patients with benign and malignant neoplasms of the breast and prostate glands and to evaluate the possibility of their use as diagnostic and prognostic markers. Object and methods: the study was performed on clinical material of 90 patients with stage I–III breast cancer, 20 patients with benign breast tumors, 80 patients with stage II–IV prostate cancer and 20 patients with benign prostatic hyperplasia. MicroRNA levels were determined by real-time reverse transcription PCR. Results: an increase in the expression of tumor-associated miRNA-21 and-221 in the tissues of both studied malignant hormone-dependent cancers compared with benign tumors was established. We showed the correlations of the studied miRNA levels with some clinical and pathological characteristics of patients with BC and PCa, which have prognostic value (age of patients, stage of the disease, tumor size, presence of lymph node lesion, degree of differentiation, molecular subtype and PSA level in patients’ serum), indicate the participation of these miRNAs in the formation of the BC malignancy degree of and the association with the aggressiveness of studied diseases. Conclusion: the results indicate the relationship of the main clinical and pathological characteristics of patients with BC and PCa with expression levels of miRNA-21, -125b and -221, which justifies the need to continue studying the proposed panel of miRNAs for use as additional prognostic and diagnostic markers.