Fib-EXO increased the expression of vimentin, EZH2, DNMT1, TGF-β3, and c-MYC, and phosphorylated p65 protein, reduced COL1A1 and COL3A1 expression, and decreased miR-133a, miR-29, and miR-200c while increasing miR-21 in cultured myometrial smooth muscle cells, mirroring changes observed in fibroids. This evidence concerns the gene COL1A1 and leiomyoma.