Notch2 and Notch3 suppress the proliferation and mediate invasion of trophoblast cell lines.

Notch signaling pathways play important roles in cell fate and many diseases, including preeclampsia, the dysregulation of which may be the main cause of maternal mortality. This study aimed to investigate the roles of Notch2 and Notch3 in proliferation and invasion in trophoblast cell lines (BeWo and JAR). Small hairpin RNAs targeting Notch2/Notch3 and Notch2/Notch3-overexpression vectors were designed, constructed and transfected into BeWo and JAR cells. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were then used to detect Notch2 and Notch3 mRNA and protein levels, and confirm the efficiency of silence and overexpression. Flow cytometry assays were conducted to evaluate the cell cycle of the two cell lines, and transwell assays were used to detect migration and invasion. Western blot analysis was also performed to show the alteration of the cell lines' physiological activities at protein level.When Notch2 was downregulated in BeWo cells, proliferation was dramatically promoted, while migration and invasion were significantly inhibited. When Notch2 was upregulated in JAR cells, proliferation was inhibited, but migration and invasion were promoted. After overexpression of Notch3 in BeWo cells, proliferation was downregulated, but migration and invasion were both upregulated. By contrast, the silencing of Notch3 expression in JAR cells significantly enhanced proliferation, but suppressed migration and invasion. These data indicated that Notch2 and Notch3 mediate the invasion and migration of BeWo and JAR cells, and may play a potential role in early onset severe preeclampsia.

Effects of Notch2 and Notch3 on Cell Proliferation and Apoptosis of Trophoblast Cell Lines.

AIMS: To investigate the effect of Notch2 and Notch3 on cell proliferation and apoptosis of two trophoblast cell lines, BeWo and JAR. METHODS: Notch2 and Notch3 expression in BeWo and JAR cells was upregulated or downregulated using lentivirus-mediated overexpression or RNA interference. The effect of Notch2 and Notch3 on cell proliferation was assessed by the CCK-8 assay. The effect of Notch2 and Notch3 on the apoptosis of BeWo and JAR cells was evaluated by flow cytometry using the Annexin V-PE Apoptosis kit. Lentivirus-based overexpression vectors were constructed by cloning the full-length coding sequences of human Notch2 and Notch3 C-terminally tagged with GFP or GFP alone (control) into a lentivirus-based expression vector. Lentivirus-based gene silencing vectors were prepared by cloning small interfering sequences targeting human Notch2 and Notch3 and scrambled control RNA sequence into a lentivirus-based gene knockdown vector. The effect of Notch2 and Notch3 on cell proliferation was assessed by the CCK-8 assay. And the effect of Notch2 and Notch3 on the apoptosis of BeWo and JAR cells was evaluated by flow cytometry using the Annexin V PE Apoptosis kit. RESULTS: We found that the downregulation of Notch2 and Notch3 gene expression in BeWo and JAR cells resulted in an increase in cell proliferation, while upregulation of Notch3 and Notch2 expression led to a decrease in cell proliferation. Moreover, the overexpression of Notch3 and Notch2 in BeWo and JAR cells reduced apoptosis in these trophoblast cell lines, whereas apoptosis was increased in the cells in which the expression of Notch3 and Notch2 was downregulated. CONCLUSIONS: Notch2 and Notch3 inhibited both cell proliferation and cell apoptosis in BeWo and JAR trophoblast cell lines.

Expression of notch family proteins in placentas from patients with early-onset severe preeclampsia.

OBJECTIVES: This study is aimed to identify the expression of Notch family proteins in placentas from patients with early-onset severe preeclampsia. STUDY DESIGN: The expression of Notch family proteins in placentas was investigated by immunohistochemistry, Western blotting, and real-time reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The profile of distribution of all Notch family proteins in placentas from patients with early-onset severe preeclampsia is similar to that in normal placentas. All Notch family proteins are expressed in placental trophoblasts. Moreover, Notch1 and Jagged1 (Jag1) are detected in placental endothelial cells. Real-time RT-PCR showed that messenger RNA levels of Notch2 and Delta-like4 (Dll4) in placentas from patients with early-onset severe preeclampsia are lower than that of normal placentas. Western blotting showed a significant increase in Notch3 expression and a significant decrease in Notch2 expression in placentas from patients with early-onset severe preeclampsia relative to those in normal placentas. CONCLUSION: The results suggest that Notch2 and Notch3 may play some roles in the pathogenesis of preeclampsia.

Notch signaling pathway and human placenta.

Notch signaling was evolutionarily conserved and critical for cell-fate determination, differentiation and many other biological processes. Growing evidences suggested that Notch signaling pathway played an important role in the mammalian placental development. All of the mammalian Notch family proteins had been identified in human placenta except Delta-like 3, which appeared to affect the axial skeletal system. However the molecular mechanisms that regulated the Notch signaling pathway remained largely unknown in human placenta. Therefore, additional research was needed to investigate expression pattern of Notch family members and the mechanisms for activation of Notch signaling pathway in human placenta, which might help elucidate the roles of Notch signaling pathway in human placentation. This review would focus on the roles of Notch receptors and ligands in the human placental trophoblasts function and placental angiogenesis. It might hopefully provide perspectives for future research about human placentation of pregnancy complicated by preeclampsia and other placenta associated diseases.

[Perinatal management and pregnancy outcome in pregnant women with pulmonary hypertension complicating cardiac disease].

OBJECTIVE: To evaluate the pregnancy outcome of women with pulmonary hypertension complicating cardiac disease. METHODS: Clinical data of 61 cases of pregnant women with pulmonary hypertension from Jan 1996 to Aug 2004 were analyzed and they were divided into three groups: 32 cases of slight group [pulmonary hypertension from 30 mm Hg (1 mm Hg = 0.133 kPa) to 49 mm Hg], 23 cases of moderate group (pulmonary hypertension from 50 mm Hg to 79 mm Hg) and 6 cases of severe group (pulmonary hypertension equal to or higher than 80 mm Hg). The types of heart disease, cardiac functional status (New York heart association, NYHA), gestational weeks of pregnancy termination, mode of delivery and outcomes of infants were compared between the groups. RESULTS: (1) The occurrence rate of NYHA class III - IV was 5/6 in severe group. The rate of NYHA class I - II was 72% (23/32) in slight group. (2) The rate of moderate and severe pulmonary hypertension was 53% (11/21) and of NYHA class IV 43% (9/21) in rheumatic heart disease. The rate of slight pulmonary hypertension was 97% (35/36) and NYHA class I - II 81% (29/36) in congenital heart disease. (3) The rate of term delivery was 75% (24/32) and the birth weight was 2744 g on average in slight group. The rate of term delivery was 48% (11/23), preterm labor 35% (8/23), abortion 17% (4/23) in moderate group. The rate of term delivery was 1/6, preterm labor occurred in 3 cases, and abortion in 2 cases in severe group. The rates of neonatal complications between the three groups had no significant difference. (4) Caesarean section rate was 79% (48/61) among all patients. (5) Overall maternal mortality was 2% (1/61). CONCLUSIONS: The rate of heart failure increases gradually with the severity of pulmonary hypertension. The severity of pulmonary hypertension in rheumatic heart disease is higher than in congenital heart disease. The rate of maternal mortality and fetal loss increases in pregnant women with pulmonary hypertension complicating cardiac disease. Perinatal morbidity is higher than normal. Cesarean section is more suitable for those women.