Prostate cancer(PCa) is the second most common cause of cancer-related death in men after lung cancer. Diagnostic methods such as measurement of serum Prostate-specific antigen (PSA) levels used in the clinic still cannot distinguish between benign conditions and prostate cancer, and biopsy is essential for the diagnosis of prostate cancer. Due to the high false-positive rate of PSA, many patients are accidentally biopsied, which carries various risks for patients. Therefore, there is a need for new diagnostic methods to support PSA and the identification of reliable biomarkers for early diagnosis.

microRNAs (miRNAs) are short non-coding RNAs that can be detected in body fluids such as urine, blood and serum. In recent years, miRNAs have been nominated as reliable biomarkers that help us make an accurate diagnosis in many diseases, such as cancer. Although various miRNAs have been detected in the sera of prostate cancer patients, there is still little data on which miRNAs can be used as biomarkers.

In this study, investigators aimed to evaluate the expression levels of miR-107, miR-134-5p, miR-149-5p, miR-370-3p and miR-221 in blood as biomarkers capable of distinguishing PCa from benign prostatic hyperplasia (BPH) and will prevent unnecessary biopsies. In addition, they aimed to compare some clinical features such as serum PSA and Gleason Score with serum miRNA levels and determine the relationship between them.

The present study is a prospective study and consists of three work packages. First, clinical evaluations were made and biopsy samples were taken from patients who applied to the urology clinic, had serum PSA levels higher than 4 ng/ML, and were suspected of prostate cancer. Then, a pathological examination of the biopsy samples was performed and the patients were grouped into PCA and BPH. Finally, molecular analyses were performed on blood samples obtained from patients and healthy controls and all obtained data were statistically evaluated.

Inclusion Criteria:

• For all groups, between 40-70 years of age.
• Prostate cancer group: Patients with positive digital rectal examination (DRE) results, serum PSA level above 4 ng/mL and a confirmed pathological diagnosis of Prostate cancer.
• BPH group: Patients with a PSA level over 4 ng/mL and a negative DRE result who were clinically and pathologically diagnosed with BPH.
• Control: Healthy volunteers who applied to the urology outpatient clinic for routine check-ups and whose PSA value was below 4 ng/ml.

Exclusion Criteria:

• To have undergone drug therapy or surgery for prostate cancer,
• To have chronic inflammatory or infectious diseases,
• Were hospitalized within the past year for a chronic illness,
• To have another known malignancy,
• Being outside the age limit of 40-70.

Since the study was about prostate cancer, only male patients were included in the study.

Patients applying to the Urology Clinic of Alanya Alaaddin Keykubat University Training and Research Hospital.

The study included 20 PCa and 17 BPH patients who were clinically and pathologically confirmed, aged between 40 and 70, and had serum PSA levels above 4 ng/mL. Additionally, 20 healthy volunteers were included in the study as the control group.

The clinical diagnosis of patients included in the study was conducted at the University Training and Research Hospital Urology Outpatient Clinic, with pathological assessments performed in the Pathology Laboratory. miRNA expression analyses were performed using quantitative real-time polymerase chain reaction (qRT- PCR) in peripheral blood samples.

All statistical analyses were performed using GraphPad Prism-5 (ver.9.0). Analyses were performed using the Kruskal-Wallis rank or Mann Whitney-U test and Spearman's test was used for correlation analysis. The role of miRNAs as biomarkers in PCa was investigated by drawing the receiver operating characteristic (ROC) curves. Statistical significance was taken as p <0.05.

Ethical approval: 13.02.2020; Project start and completion: 01.06.2020-02.03.2023; Patient registration start and completion: 26.01.2021-05.12.2022; The project duration lasted 2 years and 9 months in total.

IPD and any additional supporting information can be shared with investigators who write about Prostate cancer.