PTSMT have an increased MYC expression [1] and low levels of THBS1 but no up-regulation of the miR 17~92 cluster, including miR-19a (in PTSMT mean relative expression level 0.02 versus 0.03 in leiomyomas) and miR-19b (mean 1.63 in PTSMT versus 2.23 in leiomyomas) [29]. Here, THBS1 is linked to leiomyoma.