This fluctuating behavior of miRNAs was significant in responder patients compared to non-responders, and the change in miRNA19a-3p significantly associated CRC patients with high ERK, EGFR, and PTEN protein levels making the level of miRNA19a-3p at the end of 5-FU-based therapy a significant predictor for disease recurrence and progression. The gene discussed is EGFR; the disease is colorectal carcinoma.