Then nine key miRNAs (miR-217, miR-144, miR-129, miR-125a, miR-125b, miR-375, miR-328, miR-486, and miR-194) and five hub genes (PPARGC1A, COL1A1, SYT1, PGR, and KCNB1) are confirmed to have prognostic value in COAD. The gene discussed is COL1A1; the disease is colon adenocarcinoma.