Immunohistochemical distribution of cell cycle proteins PCNA, Ki67, siklin D3, p27 and p57 in normal and pathological placentas

The placenta is a regulator organ for many metabolic activities between mother and fetus. Therefore fetal growth is directly related to the placental development. Placental development is a series of events that depend on the coordinated action of trophoblast cells? proliferation, differentiation and invasion. Studies on cell cycle related proteins which control these events are fairly limited.How placental tissue proliferation is affected by preeclampsia (PE), diabetes and intrauterine growth retardation (IUGR) is not exactly known yet. Therefore in this study, the immunohistochemical localizations of cell cycle related proteins like PCNA, Ki67, cyclin D3, p27 and p57 in the differentiation, proliferation and apoptosis mechanisms of normal, preeclamptic, diabetic and IUGR placenta were investigated.In the study, a total of 12 human term placentas consisting of 3 preeclamptic, 3 diabetic, 3 IUGR and 3 normal pregnancy placentas were used. After routine tissue processing, tissues embedded in paraffin. Tissue sections prepared from the embedded tissue samples were stained via immunohistochemistry with PCNA, Ki67, cyclin D3, p27 and p57 antibodies and were examined by light microscopy.Comparing to control placentas, PCNA, Ki67 and cyclin D3 staining intensities were significantly increased in villous parts of PE and diabetes groups while significantly decreased in basal plates of PE group. In chorionic plates, p27 and p57 staining intensities were significantly increased in PE group whilst decreased in diabetic group. In all parts of IUGR placentas, PCNA, Ki67 and cyclin D3 staining intensities were significantly reduced. p27 staining intensity of IUGR group was significantly increased in villous and basal plates and p57 staining intensity was increased significantly in all parts of IUGR placentas as well.In conclusion, cell cycle related proteins PCNA, Ki67, cyclin D3, p27 and p57 play roles in normal and pathological placental development and there is a relation between the immunoreactivity of these proteins and the size of placentas.