Exploratory Analysis of Circulating Serum miR-197-3p, miR-1236, and miR-1271 Expression in Early Breast Cancer

Early detection of breast cancer (BC) remains a challenge despite advances in screening, leading to poor prognosis in late-stage disease. Circulating microRNAs (miRNAs) have emerged as promising non-invasive biomarkers for early diagnosis. The study aimed to evaluate the diagnostic utility of serum miR-197-3p, miR-1236, and miR-1271 levels in distinguishing BC patients from healthy individuals. Serum samples from 92 BC patients and 31 healthy controls were analyzed. Total RNA was extracted, and miRNA expression levels were quantified using quantitative real-time PCR (qRT-PCR). Expression differences were assessed using the ΔCt method. Receiver Operating Characteristic (ROC) curve analysis evaluated diagnostic performance. Serum miR-197-3p levels were significantly upregulated (fold change = 8.939, p = 0.0048), while miR-1236 was downregulated (fold change = 0.112, p = 0.0029) in BC patients. miR-1271 showed no significant association. miR-1236 demonstrated superior diagnostic performance (AUC = 0.731, sensitivity = 80.7%, specificity = 51.3%) compared to miR-197-3p (AUC = 0.667, sensitivity = 67.0%, specificity = 45.6%). The combination of miR-197-3p and miR-1236 improved diagnostic accuracy (AUC = 0.842, CI: 0.764-0.936). Serum miR-197-3p and miR-1236 hold promise as complementary biomarkers for early BC detection. Larger multicenter studies are warranted to validate their clinical utility.