PGR and neoplasm: Progesterone, interacting similarly as with its specific receptors (progesterone receptors, PRs), and with non-genomic membrane receptors (mPRs/PGRMCs), activates a number of signaling pathways (WNT/β-catenin, PI3K/AKT pathways) that stimulate the growth/proliferation of myomatous cells, promote their survival (by reducing apoptosis), lead to certain vascular changes that improve blood supply to fibroids and cause UM-significant modification of the extracellular matrix (it is a key component of the tumor structure) [82,83,84,85,86,87,88,89].