Jeong Kyu Shin

DHA and EPA Down-regulate COX-2 Expression through Suppression of NF-κB Activity in LPS-treated Human Umbilical Vein Endothelial Cells

Inflammatory processes of vascular endothelial cells play a key role in the development ofatherosclerosis. We determined the anti-inflammatory effects and mechanisms of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on LPS-treated human umbilical vein endothelial cells (HUVECs) to evaluate their cardioprotective potential. Cells were pretreated with DHA, EPA, or troglitazone prior to activation with LPS. Expression of COX-2, prostaglandin E(2) (PGE(2)) and IL-6 production, and NF-kappaB activity were measured by Western blot, ELISA, and luciferase activity, respectively. Results showed that EPA, DHA, or troglitazone significantly reduced COX-2 expression, NF-kappaB luciferase activity, and PGE(2) and IL-6 production in a dose-dependent fashion. Interestingly, low doses (10 microM) of DHA and EPA, but not troglitozone, significantly increased the activity of NF-kappaB in resting HUVECs. Our study suggests that while DHA, EPA, and troglitazone may be protective on HUVECs under inflammatory conditions in a dose-dependent manner. However there may be some negative effects when the concentrations are abnormally low, even in normal endothelium.

Inhibition of the PI3K-Akt Pathway Suppresses sFlt1 Expression in Human Placental Hypoxia Models In Vitro

OBJECTIVE Although elevated expression of soluble fms-like tyrosine kinase 1 (sFlt1) plays a major role in the pathogenesis of pre-eclampsia, it is unclear how hypoxia regulates placental sFlt1 expression. Thus, we investigated sFlt1 expression in placentas from normal and preeclamptic pregnancies and in human placental hypoxia models in vitro to examine the role of the PI3K-Akt pathway in regulating the expression of this molecule. METHODS We examined the expression of VEGF, PlGF, sFlt1, PI3K, Akt, and HIF-1 in placental samples from ten women with pre-eclampsia and ten normotensive control patients and in human choriocarcinoma trophoblast cells treated with 600muM CoCl(2) by Western blotting. Using models of placental hypoxia, we also determined whether inhibition of the PI3K-Akt pathway plays a direct role in regulating the expression of sFlt1. RESULTS The VEGF, PlGF, sFlt1, PI3K, Akt, and HIF-1 levels were significantly higher in the preeclamptic placentas than the normal placentas. In the placental hypoxia models, the expression of VEGF and PlGF increased in a time-dependent manner, whereas the expression of sFlt1 plateaued after 3h of CoCl(2) treatment. The expression levels of p-Akt and PI3K were maximal after 6 and 12h of CoCl(2) treatment, respectively. The expression of HIF-1alpha increased in a time-dependent manner with CoCl(2) treatment. Inhibition of the PI3K-Akt pathway with the PI3K-specific inhibitor LY294002 leads to decreased sFlt1 levels and unchanged or increased VEGF and PlGF levels. CONCLUSION Inhibition of the PI3K-Akt pathway may be a useful therapeutic approach, if it were to decrease sFlt1 secretion without inhibiting VEGF or PlGF secretion. This pathway provides a potential target for a new treatment strategy in patients with pre-eclampsia.

Failure of uterine artery embolization for controlling postpartum hemorrhage

Aim:  We evaluated the efficacy of uterine artery embolization (UAE) for controlling postpartum hemorrhage (PPH).

Increased NFAT5 expression stimulates transcription of Hsp70 in preeclamptic placentas

OBJECTIVE We investigated the expression of heat shock protein 70 (Hsp70), nuclear factor of activated T cells 5 (NFAT5), and hypoxia-induced factor-1α (HIF-1α) in the placentas of normal and preeclamptic pregnancies and in human placental hypoxia models in vitro to examine the regulatory mechanisms of placental Hsp70 expression. METHODS The expression levels of HIF-1α, NFAT5, and Hsp70 were examined in placental samples from 10 females with preeclampsia and 10 normotensive control patients and in human choriocarcinoma trophoblast cells treated with 1 mM CoCl2 by western blotting. Using models of placental hypoxia, pharmacological inhibition of HIF-1α with chetomin and shRNA knockdown and overexpression of NFAT5 were performed to investigate the roles of HIF-1α and NFAT5 in induction of Hsp70 by placental hypoxia. RESULTS The levels of HIF-1α, NFAT5, and Hsp70 expression were significantly higher in the preeclamptic compared to normal placentas. In the placental hypoxia models, the expression of HIF-1α, NFAT5, and Hsp70 were significantly higher after 3, 6, and 12 h of 1 mM CoCl2 treatment, respectively. Pharmacological inhibition of HIF-1α suppressed the induction of NFAT5 and Hsp70 at the protein level. shRNA knockdown of NFAT5 suppressed the induction of Hsp70 protein and overexpression of NFAT5 stimulated the induction of Hsp70 mRNA and protein in models of human placental hypoxia in vitro. CONCLUSION HIF-1α positively regulates the induction of NFAT5 and Hsp70 by placental hypoxia and NFAT5 stimulates transcription of Hsp70 in response to placental hypoxia in models of human placental hypoxia in vitro.

PKC δ in Preeclamptic Placentas Promotes Bax Dissociation from 14-3-3 ζ through 14-3-3 ζ Phosphorylation

OBJECTIVE We investigated placental apoptosis and the expression of and interactions between 14-3-3 and Bcl-2 family proteins during preeclampsia. In addition, we explored the mechanism of Bax dissociation from 14-3-3, hypothesizing that PKC-mediated phosphorylation of 14-3-3 results in dissociation of Bax from 14-3-3 proteins, and leads to apoptosis. METHODS Placental samples from 10 women with preeclampsia and 10 normotensive control patients were analyzed using M30-specific immunohistochemistry to assess placental apoptosis. Biochemical markers of cellular apoptosis, such as cleaved caspase-3, Bax, Bcl-2, 14-3-3, and PKC were followed by Western blotting. Interaction of 14-3-3 proteins with Bax and with PKC was assessed by immunoprecipitation. RESULTS M30-positive cells were widespread in the preeclamptic placentas. The levels of cleaved caspase-3, Bax, 14-3-3 zeta, phospho-(Ser)-14-3-3, and PKC delta were significantly higher in the preeclamptic placentas than in normal placentas. Preeclampsia was also associated with weaker interactions between 14-3-3 zeta and Bax and stronger interactions between 14-3-3 zeta and PKC delta. CONCLUSION Our results suggest that PKC delta in preeclamptic placentas promotes Bax dissociation from 14-3-3 zeta through the phosphorylation of 14-3-3 zeta. This finding may at least in part explain the apoptosis-inducing activity of PKC delta, revealing the important role of PKC delta in the development of apoptosis-related diseases such as preeclampsia.

Regulation of the epithelial to mesenchymal transition and metastasis by Raf kinase inhibitory protein-dependent Notch1 activity

Raf kinase inhibitory protein (RKIP), an endogenous inhibitor of the extracellular signal-regulated kinase (ERK) pathway, has been implicated as a suppressor of metastasis and a prognostic marker in cancers. However, how RKIP acts as a suppressor during metastasis is not fully understood. Here, we show that RKIP activity in cervical and stomach cancer is inversely correlated with endogenous levels of the Notch1 intracellular domain (NICD), which stimulates the epithelial to mesenchymal transition (EMT) and metastasis. The levels of RKIP were significantly decreased in tumor tissues compared to normal tissues, whereas NICD levels were increased. Overexpression of RKIP in several cell lines resulted in a dramatic decrease of NICD and subsequent inhibition of several mesenchymal markers, such as vimentin, N-cadherin, and Snail. In contrast, knockdown of RKIP exhibited opposite results both in vitro and in vivo using mouse models. Nevertheless, knockdown of Notch1 in cancer cells had no effect on the expression of RKIP, suggesting that RKIP is likely an upstream regulator of the Notch1 pathway. We also found that RKIP directly interacts with Notch1 but has no influence on the intracellular level of the γ-secretase complex that is necessary for Notch1 activation. These data suggest that RKIP plays a distinct role in activation of Notch1 during EMT and metastasis, providing a new target for cancer treatment.

Torsion of a parasitic myoma that developed after abdominal myomectomy

Iatrogenic parasitic myomas are rare. The condition is defined by the presence of multiple smooth-muscle tumorous nodules in the peritoneal cavity. This may be attributable to seeding of myoma particles during uterine surgery. The clinical course is usually indolent. The disease is often asymptomatic and is usually discovered only incidentally. A 38-year-old woman who had undergone abdominal myomectomy 7 months prior presented with acute abdominal pain and a huge pelvic mass. We performed exploratory laparotomy. A parasitic mass 17 cm in diameter with a twisted omental pedicle was identified. En bloc excision of the mass and omentum was performed, followed by total abdominal hysterectomy. Histopathological examination of multiple sections revealed features compatible with an infarcted leiomyoma. Thus, we present a very rare case of an iatrogenic, rapidly growing parasitic myoma complicated by omental torsion (which caused the acute abdominal pain). We also offer a literature review.

Pseudoexstrophy of the bladder diagnosed prenatally

Department of Urology, School of Medicine, Gyeongsang National University, JinJu, Korea Department of Surgery, School of Medicine, Gyeongsang National University, JinJu, Korea Department of Obstetrics and Gynecology, School of Medicine, Gyeongsang National University, JinJu, Korea Institute of Health Sciences, School of Medicine, Gyeongsang National University, JinJu, Korea *Correspondence to: Ji Kwon Park. E-mail: obgypjk@gnu.ac.kr

Molecular cytogenetic investigation of a balanced complex chromosomal rearrangement carrier ascertained through a neonate with partial trisomies of 13 and 22

Complex chromosomal rearrangement (CCR) is a structural abnormality of chromosomes that rarely appears in individuals with normal phenotypes. A CCR involving chromosomes 9, 13, and 22 was ascertained in a phenotypically normal woman through a neonate with multiple congenital malformations and partial trisomies of 13 and 22. We diagnosed the CCR using high‐resolution chromosome analysis and three‐color fluorescence in situ hybridization (three‐color FISH) analysis, and ascertained a balanced CCR without cryptic imbalances using array comparative genomic hybridization (array CGH) and FISH. In the present work, we report on the case together with a literature review.

O-linked N-acetylglucosamine transferase promotes cervical cancer tumorigenesis through human papillomaviruses E6 and E7 oncogenes.

O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) increases O-GlcNAc modification (O-GlcNAcylation), and transcriptional co-regulator host cell factor 1 (HCF-1) is one of OGT targets. High-risk Human Papillomaviruses (HPVs) encode E6 and E7 oncoproteins, which promote cervical cancer. Here, we tested whether O-GlcNAc modification of HCF-1 affects HPV E6 and E7 expressions and tumorigenesis of cervical cancer. We found that depleting OGT with OGT-specific shRNA significantly decreased levels of E6 and E7 oncoproteins, and cervical cancer tumorigenesis, while OGT overexpression greatly increased levels of E6 and E7 oncoproteins. Notably, OGT overexpression caused dose-dependent increases in the transcriptional activity of E6 and E7, and this activity was decreased when HCF-1 was depleted with HCF-1-specific siRNA. Moreover, OGT depletion reduced proliferation, invasion, and metastasis in cervical cancer cells. Further, high glucose enhanced the interaction between OGT and HCF-1, paralleling increased levels of E6 and E7 in cervical cancer cells. Most importantly, we found that reducing OGT in HeLa cells caused decreased tumor growth in vivo. These findings identify OGT as a novel cellular factor involved in E6 and E7 expressions and cervical cancer tumorigenesis, suggesting that targeting OGT in cervical cancer may have potential therapeutic benefit.