CCN2 and endometriosis: We propose, that the main common target for the action of all these factors are endometriosis epithelial stem cells, and that stromal mesenchymal/bone marrow-derived stem cells are one of the most relevant modulators of carcinogenesis via CTGF secretion, and modulation of the endometriotic niche (shaping resistance to hypoxic stress, regulation of mesothelial-to-mesenchymal transition and fibrosis, ECM remodeling and angiogenesis).