Can benign (non-cancerous) conditions cause miRNA overexpression?

Certain benign conditions can cause transient or modest miRNA elevation. Benign prostatic hyperplasia (BPH) has been associated with modest miR-21 elevation in some studies. Inflammatory bowel disease (IBD) and endometriosis have been linked to miR-21 changes. However, Yenos's validation data shows zero overlap between healthy and cancer populations using the 1.5× HL threshold — and the healthy control group in these studies included individuals who may have had benign conditions. The HL threshold was calibrated to produce this clean separation. A single confirmed elevation (above 1.5× HL) on initial testing triggers a second confirmatory test on the same sample — and if both tests are elevated, the probability of a true cancer signal is very high. That said, anyone with a known inflammatory condition should discuss this with their physician when interpreting their results.