Implication of circulating microRNA-21 as a potential non-invasive diagnostic predictor of prostate cancer patients

Background: Prostate cancer is a major cause of morbidity and mortality worldwide with an increasing incidence every year leading to enlarged socioeconomic burden and poor quality of life of patients. Current diagnostic approaches are non-specific and have inadequate clinical applicability due to reduced sensitivity and specificity. Aim: To evaluate the significance of circulatory microRNA-21 as a non-invasive diagnostic tool for prostate cancer patients with high level of sensitivity and specificity irrespective of the patient's age. Methods: A total of 64 men, including 32 patients with prostate cancer and 32 healthy controls were enrolled in this study. Circulating microRNA was extracted from serum samples using miRNeasy Serum/Plasma Kit (Cat No. 217184, Qiagen). Circulating microRNA-21 was quantified using SYBR Green-based relative quantification assay. The age-wise (<50 years and > 50 years) correlation of microRNA-21 expression with serum Prostate-specific antigen (PSA) levels was performed to determine their possible association. Results: Circulating microRNA-21 showed significantly upregulated expression in patients compared to control individuals with 71.05% sensitivity and 77.35% specificity (p < 0.0001). Age-wise analysis showed significantly increased expression levels of microRNA-21 in both the younger and older patients (for both p < 0.0001) compared to respective control individuals. The XY analysis showed positive correlation between microRNA-21 expression and PSA levels (r = 0.03012; p = 0.8992). The trend in values of microRNA-21 expression was corresponding to the serum PSA levels. Conclusion: Circulating microRNA-21 levels with serum PSA can be used as a non-invasive tool for accurate diagnosis of prostate cancer patients to overcome the constraints of current approaches for timely management.