Small leucine rich proteoglycans are differently expressed in normal and pathological endometrium

During the woman’s fertile period, the non pregnant uterusis subject to constant cyclic changes, involving mainly theendometrial and myometrial tissue. The cell cycle modificationinduced the switching from a high proliferative state to a dif-ferentiation state, typical of the secretory phase. The complexmechanisms that control the balance between proliferation,differentiation, cell death and the structural remodeling of theextracellular matrix can contribute to the benign or malignantendometrial pathological state. The small leucine-rich proteo-glycans (SLRPs) are important components of cell surfaceand extracellular matrices. In the present paper we describethe distribution of SLRPs in the physiological endometriumand in the pathological endometrium. Through immunohisto-chemistry we have shown that the distribution patterns ofSLRPs were completely modified in the pathologicalendometrium as compared to normal endometrium. The expression of SLRPs was low/absent in all the endome-trial pathologies examined as compared to normal endometri-um. We observed an increase of lumican from proliferative tosecretory phase of the endometrium and a decrease of fibro-modulin, biglycan, and decorin. In menopause endometrial tis-sue the level of expression of fibromodulin, biglycan, decorinand lumican dramatically decreased. The results reveal the prominence and importance of pro-teoglycans in the tissue architecture and extracellular matrixorganization.