Why does chemotherapy affect miRNA levels?

Chemotherapy and radiation therapy cause massive cell death (both cancerous and normal cells) and trigger profound inflammatory and stress responses throughout the body. These processes dramatically alter miRNA expression and release patterns. Dying tumor cells release large amounts of intracellular miRNA, which can temporarily spike miRNA levels in blood and urine. Simultaneously, the cytotoxic effects on normal tissue alter the baseline miRNA expression of healthy cells. Because OncuraKit's threshold is calibrated for people not in active treatment, the miRNA landscape during or immediately after chemotherapy or radiation is too disrupted to interpret accurately with the standard HL reference. This is why active cancer treatment is a contraindication.