Laparoscopic surgery for fallopian tube torsion due to benign tumour in the third trimester of pregnancy: a case report and literature review.

Isolated fallopian tubal torsion is rare among women of reproductive age, and it is even rarer during pregnancy. Despite its rare incidence, it is important to consider this diagnosis to facilitate prompt and effective intervention. We present the case of a pregnant woman in her third trimester who presented with acute right abdominal pain. A 32-year-old primigravida woman at 29 weeks and four days of gestation visited the emergency department with acute right flank and abdominal pain. Sonography and MRI revealed the presence of a right adnexal cystic mass. Exploratory laparoscopy revealed isolated right tubal torsion and a normal ovary. To avoid torsion recurrence, we performed laparoscopic right salpingectomy. The remainder of her gestation was uneventful. Histopathological examination revealed serous cystadenoma with haemorrhagic infarction. We reviewed the literature for cases of isolated tubal torsion in the past 11 years. Twenty-three case reports were included in this study, and the average time from presentation to surgical intervention was 35.6 hours. In these cases, most of the patients underwent laparotomy and had good pregnancy outcomes. Although the approach may vary depending on the situation, the laparoscopic approach should be preferred to laparotomy in the third trimester of pregnancy.

Who Really Benefits from 3D-Based Planning of Brachytherapy for Cervical Cancer?

BACKGROUND: Although intracavitary radiotherapy (ICR) is essential for the radiation therapy of cervical cancer, few institutions in Korea perform 3-dimensional (3D)-based ICR. To identify patients who would benefit from 3D-based ICR, dosimetric parameters for tumor targets and organs at risk (OARs) were compared between 2-dimensional (2D)- and 3D-based ICR. METHODS: Twenty patients with locally advanced cervical cancer who underwent external beam radiation therapy (EBRT) following 3D-based ICR were retrospectively evaluated. New 2D-based plans based on the Manchester system were developed. Tumor size was measured by magnetic resonance imaging. RESULTS: The mean high risk clinical target volume (HR-CTV) D90 value was about 10% lower for 2D- than for 3D-based plans (88.4% vs. 97.7%; P = 0.068). Tumor coverage did not differ between 2D- and 3D-based plans in patients with tumors ≤ 4 cm at the time of brachytherapy, but the mean HR-CTV D90 values in patients with tumors > 4 cm were significantly higher for 3D-based plans than for 2D-based plans (96.0% vs. 78.1%; P = 0.017). Similar results were found for patients with tumors > 5 cm initially. Other dosimetric parameters for OARs were similar between 2D- and 3D-based plans, except that mean sigmoid D2cc was higher for 2D- than for 3D-based plans (67.5% vs. 58.8%; P = 0.043). CONCLUSION: These findings indicate that 3D-based ICR plans improve tumor coverage while satisfying the dose constraints for OARs. 3D-based ICR should be considered in patients with tumors > 4 cm size at the time of brachytherapy or > 5 cm initially.

Selection of reference genes for quantitative real-time polymerase chain reaction in porcine embryos.

To study gene expression and to determine distinctive characteristics of embryos produced by different methods, normalisation of the gene(s) of interest against reference gene(s) has commonly been employed. Therefore, the present study aimed to assess which reference genes tend to express more stably in single porcine blastocysts produced in vivo (IVO) or by parthenogenetic activation (PA), in vitro fertilisation (IVF) and somatic cell nuclear transfer (SCNT) using different analysis programs, namely geNorm, Normfinder and Bestkeeper. Commonly used reference genes including 18S rRNA (18S), H2A histone family, member Z (H2A), hypoxanthine phosphoribosyltransferase1 (HPRT1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), ribosomal protein 4 (RPL4), peptidylprolyl isomerase A (PPIA), beta actin (ACTB), succinate dehydrogenase complex, subunit A (SDHA) and hydroxymethylbilane synthase (HMBS2) were analysed; most of them resulted in significantly (P<0.05) different cycle threshold (CT) values in porcine embryos except for SDHA and H2A. In evaluation of stable reference genes across in vivo and in vitro porcine blastocysts, three kinds of programs showed slightly different results; however, there were similar patterns about the rankings of more or less stability overall. In conclusion, SDHA and H2A were determined as the most appropriate reference genes for reliable normalisation in order to find the comparative gene expression in porcine blastocysts produced by different methods, whereas 18S was regarded as a less-stable reference gene. The present study has evaluated the stability of commonly used reference genes for accurate normalisation in porcine embryos to obtain reliable results.

Huge vaginal stone: Case report and review of the literature.

Primary vaginal stones have been rarely reported; the reports that do exist are usually case reports. Because of their low incidence, they are often misdiagnosed. This case report and literature review of a primary vaginal stone presents an assessment of symptoms and common risk factors for vaginal stone formation. A 28-year-old woman with spastic quadriplegia who had been bedridden for most of her life presented to the emergency department for abdominal distension and fever. She had chronic constipation, recurrent urinary tract infections (UTIs), and vaginal discharge. Abdominopelvic computed tomography (CT) was performed and a large stone observed. The vaginal stone was completely removed through the vaginal stump after hysterectomy. Differential diagnoses of vesicovaginal fistula, urethrovaginal fistula, genital anomaly, and ectopic ureter were made by performing several tests using indigo-carmine dye. She recovered from surgery without any complications. There was no recurrence of vaginal stones after 3 months. A biochemical analysis reported that the vaginal stone was 100% struvite. Vaginal stones are caused by repeated infections in an environment in which urine collects gradually. Patients with recurrent UTIs who are bedridden should be able to prevent vaginal stones with periodic gynecological examinations for early diagnosis and management.

Serum vitamin D-binding protein (VDBP) concentration and rs7041 genotype may be associated with preterm labor.

PURPOSE: Vitamin D deficiency is common during pregnancy and may cause complications such as preterm labor (PTL). This study was aimed to investigate the effect of the vitamin D-binding protein (VDBP) rs7041 genotype, which has a significant effect on vitamin D metabolism and PTL. METHODS: This cross-sectional study was conducted with 32 pregnant women who had spontaneous PTL and 54 pregnant women who had no specific findings as a control group. Serum total vitamin D 25-hydroxy vitamin D (25(OH)D) levels were measured using the Elecsys Vitamin D Total Kit. VDBP was measured using a VDBP Quantikine ELISA Kit. The levels of bioavailable 25(OH)D were calculated based on the total 25(OH)D and VDBP concentrations. DNA was extracted using the DNeasy Blood and Tissue Kit. Single nucleotide polymorphisms (rs7041) in GC were analyzed using a TaqMan SNP Genotyping Assay Kit. The unpaired t-test, Chi-squared, and ANCOVA tests were performed. Firth's penalized logistic regression was applied. The area under the curve (AUC) was calculated and the cutoff value was determined. All statistical analyses were performed using R version 4.0.3 (R Foundation for Statistical Computing, Vienna, Austria). RESULTS: Total 25(OH)D levels were not significantly different between the two groups. Bioavailable 25(OH)D was significantly decreased in PTL women (p= .011), and VDBP was significantly increased in PTL women (p= .004) compared to the controls. Bioavailable 25(OH)D was lower in women with GT/TG and TT rs7041 genotypes than in those with GG, with statistical significance in women with the TT allele (p= .048). VDBP was higher in women with GT/TG and TT than those with GG, but there was no statistical significance. In PTL prevalence, bioavailable 25(OH)D and VDBP, the odds ratio increased by 1.463 times in GT/TG (p= .728) and increased by 1.675 times in TT compared to the GG allele (p= .640). In receiver operating characteristic (ROC) analysis for bioavailable 25(OH)D and VDBP, the AUC was 0.665 and 0685, respectively. The optimum cutoff of bioavailable 25(OH)D and VDBP levels for the diagnosis of PTL was calculated as 0.6 ng/mL and 523 µg/mL, respectively. CONCLUSIONS: Pregnant women with the VDBP rs7041(c.1296 T > G) T allele genotype had reduced serum levels of bioavailable 25(OH)D and were more likely to develop PTL. Therefore, if the T allele is found in the VDBP rs7041 SNP genotyping test before or during pregnancy, more careful prenatal care may be required because of the increased risk of PTL.

Proteomic analysis reveals an elevated expression of heat shock protein 27 in preeclamptic placentas.

AIM: The purpose of this study was to identify the placental proteins that are associated with preeclampsia by performing proteomic analysis. METHODS: To identify the proteins associated with preeclampsia, we performed two-dimensional electrophoresis (2-DE), followed by silver staining. The overexpressed proteins were identified by performing matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS), followed by peptide mass fingerprinting, a protein database search and Western blot analysis. Immunohistochemical staining was performed to determine the localization of the overexpressed Hsp27. RESULTS: By use of 2-DE and MALDI-TOF-MS analysis, twelve differentially expressed proteins were identified, of which four proteins were upregulated and eight proteins were downregulated. One of the upregulated spots was identified as Hsp27. Immunohistochemical analysis showed that Hsp27 was mainly located in the trophoblasts. The Western blot analysis showed that the expression of Hsp27 in the tissues of the preeclampsia placenta was significantly increased. CONCLUSIONS: Our study confirmed that four proteins are upregulated and eight proteins are downregulated in preeclampsia. These differentially expressed proteins include signal transduction protein and molecular chaperon protein, in which Hsp27 is upregulated. We suggest that the increased expression level of Hsp27 might be correlated with the pathophysiology of preeclampsia.

Failure of uterine artery embolization for controlling postpartum hemorrhage.

AIM: We evaluated the efficacy of uterine artery embolization (UAE) for controlling postpartum hemorrhage (PPH). MATERIALS AND METHODS: Between January 2008 and December 2009, 23 women with intractable PPH underwent UAE. Specific diagnoses included uterine atony (n = 10), placenta accreta (n = 8), puerperal hematoma (n = 2) and placental polyp (n = 3). RESULTS: Of 10 patients with uterine atony, treatment with UAE failed in two women with severe vasoconstriction. One patient developed lumbosacral plexopathy. All eight patients with placenta accreta were treated successfully with the placement of multiple sutures in the placental bed and UAE. Two of the three women with placental polyps were treated successfully with UAE and packing of the uterus. CONCLUSIONS: Embolization should follow resuscitation for vascular collapse. In the case of an adherent placenta, embolization is more effective with the placement of multiple sutures in the placental bed or compression of the placental bed.

UHRF1 Induces Methylation of the TXNIP Promoter and Down-Regulates Gene Expression in Cervical Cancer.

DNA methylation, and consequent down-regulation, of tumour suppressor genes occurs in response to epigenetic stimuli during cancer development. Similarly, human oncoviruses, including human papillomavirus (HPV), up-regulate and augment DNA methyltransferase (DNMT) and histone deacetylase (HDAC) activities, thereby decreasing tumour suppressor genes (TSGs) expression. Ubiquitin-like containing PHD and RING finger domain 1 (UHRF1), an epigenetic regulator of DNA methylation, is overexpressed in HPV-induced cervical cancers. Here, we investigated the role of UHRF1 in cervical cancer by knocking down its expression in HeLa cells using lentiviral-encoded short hairpin (sh)RNA and performing cDNA microarrays. We detected significantly elevated expression of thioredoxin-interacting protein (TXNIP), a known TSG, in UHRF1-knockdown cells, and this gene is hypermethylated in cervical cancer tissue and cell lines, as indicated by whole-genome methylation analysis. Up-regulation of UHRF1 and decreased TXNIP were further detected in cervical cancer by western blot and immunohistochemistry and confirmed by Oncomine database analysis. Using chromatin immunoprecipitation, we identified the inverted CCAAT domain-containing UHRF1-binding site in the TXNIP promoter and demonstrated UHRF1 knockdown decreases UHRF1 promoter binding and enhances TXNIP expression through demethylation of this region. TXNIP promoter CpG methylation was further confirmed in cervical cancer tissue by pyrosequencing and methylation-specific polymerase chain reaction. Critically, down-regulation of UHRF1 by siRNA or UHRF1 antagonist (thymoquinone) induces cell cycle arrest and apoptosis, and ubiquitin-specific protease 7 (USP7), which stabilises and promotes UHRF1 function, is increased by HPV viral protein E6/E7 overexpression. These results indicate HPV might induce carcinogenesis through UHRF1-mediated TXNIP promoter methylation, thus suggesting a possible link between CpG methylation and cervical cancer.

Correlational analysis of bone health status and vitamin D-related biomarkers in women working in agriculture.

ABSTRACT: The purpose of this study was to investigate the status of bone health in women working in agriculture and analyze the associations between bone health and various vitamin D-related biomarkers.This observational study enrolled women working in agriculture (n = 210) and control occupations (n = 180). The concentration of serum total 25-hydroxy vitamin D [25(OH)D] was measured using the Elecsys Vitamin D Total Kit, and serum vitamin D-binding protein (VDBP) was measured by enzyme-linked immunosorbent assay. Along with albumin, 25(OH)D and VDBP were used to calculate the concentrations of bioavailable and free 25(OH)D. Bone mineral density (BMD) and T-score were measured at lumbar 1 to 4 and the femur neck using dual-energy X-ray absorptiometry. To identify factors affecting BMD, log-linear model and linear regression analysis were performed for statistical analysis.Agricultural women workers showed higher serum concentrations of bioavailable 25(OH)D (12.8 ±â€Š3.7 vs 8.7 ±â€Š5.1 ng/mL) and lower VDBP concentrations (201.8 ±â€Š45.0 vs 216.0 ±â€Š68.2 µg/mL) than control women. The association between these 2 vitamin D related-biomarkers and femur neck BMD were confirmed through univariable and multivariable linear model analysis. Although lumbar BMD did not differ between groups, the agricultural group displayed a lower femur BMD and a 4.3-fold increase in the risk of osteoporosis compared with the control group.Women working in agriculture showed lower femur BMD than the control group. Of the vitamin D-related biomarkers tested, bioavailable 25(OH)D and VDBP were associated with BMD. As bioavailable 25(OH)D levels are affected mainly by VDBP levels, VDBP may play a role in the lower femur neck BMD values observed in the agricultural group. Thus, the measurement of VDBP concentration might be considered a simple and non-invasive method for measuring bone health status.

Increased interaction between heat shock protein 27 and mitogen-activated protein kinase (p38 and extracellular signal-regulated kinase) in pre-eclamptic placentas.

AIMS: Heat shock protein 27 (Hsp27) is a well-known stress response protein that is characterized by its phosphorylative capacity. Hsp27 becomes phosphorylated in response to various stimuli through interaction with several different kinases. The purpose of this study was to evaluate the interaction between Hsp27 and mitogen-activated protein kinase (MAPK) (p38, extracellular signal-regulated kinase [ERK], and c-Jun N-terminal kinase) in the human placenta derived from patients with pre-eclampsia. METHODS: Western blot analysis was used to examine the levels of expression of Hsp27 and MAPK (p38, ERK, and c-Jun N-terminal kinase). Immunoprecipitation analysis was used to determine the interaction between Hsp27 and MAPK (p38 and ERK). RESULTS: Western blotting analysis and immunohistochemistry showed that the expression of Hsp27 and p-Hsp27 in the placental tissues of the pre-eclampsia group were significantly higher than that in the normal pregnancy group. Immunoprecipitation analysis showed that the interaction between Hsp27 and MAPK (p38 and ERK) was significantly increased in the pre-eclamptic placenta tissues. CONCLUSION: The interaction between Hsp27 and MAPK was increased, suggesting that phosphorylation of Hsp27 might be induced by p38 and ERK in placentas from patients with pre-eclampsia.

Bilateral ovarian granulocytic sarcoma as the primary manifestation of acute myelogenous leukemia treated with allogenic stem cell transplantation: A case report.

RATIONALE: Granulocytic sarcoma (GS), also known as chloroma, is a tumor comprising myeloblasts or monoblasts, potentially occurring as an extramedullary mass. Systemic chemotherapy should be used to induce complete remission. However, such patients with chloroma have a poorer treatment outcome than those without extramedullary myeloid sarcomas. PATIENT CONCERNS: A 30-year-old woman who initially presented with bilateral ovarian masses and splenomegaly was admitted to hospital. Also, her complete blood cell counts showed pancytopenia and blood smear revealed a few immature cells (3%). DIAGNOSES: A bone marrow biopsy demonstrated acute myelomonocytic leukemia, and the chromosomal analysis revealed a 46, XX, del18 (p11) [20] karyotype and cytogenetics and molecular markers showed all negative results. INTERVENTIONS: Since this diagnosis, she received remission-inducing chemotherapy comprising anthracycline and cytarabine, which is a standard regimen for acute myeloid leukemia (AML), and followed by allogenic hematopoietic stem cell transplantation from Human leukocyte antigen (HLA)-identical sibling donor. OUTCOMES: After transplantation, the bone marrow engrafted successfully without complications. She visited our clinic regularly with no evidence of leukemia relapse or graft-versus host disease. LESSONS: This report represents the first case of ovarian GS, wherein treatment was successful with high-dose chemotherapy, followed by allogenic hematopoietic stem cell transplantation without oophorectomy.

Analysis of vitamin D-binding protein (VDBP) gene polymorphisms in Korean women with and without endometriosis.

OBJECTIVE: Vitamin D-binding protein (VDBP) mediates various biological processes in humans. The goal of this study was to investigate whether VDBP gene polymorphisms could predispose Korean women to endometriosis. METHODS: We prospectively enrolled women with endometriosis (n = 16) and healthy controls (n = 16). Total serum 25-hydroxyl vitamin D (25(OH)D) concentrations were measured using an Elecsys vitamin D total kit. Levels of bioavailable and free 25(OH)D were calculated. Concentrations of VDBP were measured using a vitamin D BP Quantikine ELISA kit. DNA was extracted using a DNeasy blood & tissue kit. Two singlenucleotide polymorphisms (SNPs; rs4588 and rs7041) in GC, the gene that codes for VDBP, were analyzed using a TaqMan SNP genotyping assay kit. The functional variant of VDBP was determined based on the results of the two SNPs. RESULTS: Gravidity and parity were significantly lower in the endometriosis patients than in the control group, but serum CA-125 levels and the erythrocyte sedimentation rate were significantly higher. Total serum 25(OH)D levels in the endometriosis patients were significantly lower than in the control group. However, serum bioavailable 25(OH)D, free 25(OH)D, and VDBP levels did not differ significantly between the endometriosis and control groups. The genotypes and allele frequencies of GC were similar in both groups. CONCLUSION: Korean women with endometriosis had lower total serum 25(OH)D concentrations than controls. Neither serum VDBP concentrations nor polymorphisms in the gene coding for VDBP were associated with endometriosis. Further studies are needed to investigate the pathophysiology and clinical implications of 25(OH)D and VDBP in endometriosis.

Differences in 25-hydroxy vitamin D and vitamin D-binding protein concentrations according to the severity of endometriosis.

OBJECTIVE: To investigate serum 25-hydroxyl vitamin D (25(OH)D) and vitamin D-binding protein (VDBP) concentrations in women with endometriosis according to the severity of disease. METHODS: Women with mild endometriosis (n = 9) and advanced endometriosis (n = 7), as well as healthy controls (n = 16), were enrolled in this observational study. Serum total 25(OH)D concentrations were analyzed using the Elecsys vitamin D total kit with the Cobas e602 module. Concentrations of bioavailable and free 25(OH)D were calculated. Concentrations of VDBP were measured using the Human Vitamin D BP Quantikine ELISA kit. Variables were tested for normality and homoscedasticity using the Shapiro-Wilk test and Leven F test, respectively. Correlation analysis was used to identify the variables related to total 25(OH)D and VDBP levels. To assess the effects of total 25(OH)D and VDBP levels in the three groups, multivariate generalized additive modeling (GAM) was performed. RESULTS: Gravidity and parity were significantly different across the three groups. Erythrocyte sedimentation rate (ESR) and CA-125 levels increased as a function of endometriosis severity, respectively (p= 0.051, p= 0.004). The correlation analysis showed that total 25(OH)D levels were positively correlated with gravidity (r = 0.59, p< 0.001) and parity (r = 0.51, p< 0.003). Multivariate GAM showed no significant relationship of total 25(OH)D levels with EMT severity after adjusting for gravidity and ESR. However, the coefficient of total 25(OH)D levels with gravidity was significant (1.87; 95% confidence interval, 0.12-3.63; p= 0.040). CONCLUSION: These results indicate that vitamin D and VDBP levels were not associated with the severity of endometriosis.

Metformin inhibits cervical cancer cell proliferation via decreased AMPK O-GlcNAcylation.

Metformin is a widely used drug for the treatment of type 2 diabetes. Antidiabetic drugs are also known to influence cancer progression, as high glucose levels affect both cancer and diabetes. Metformin induces cell cycle arrest in cancer cells, but the underlying mechanism remains unclear in cervical cancer system. Here, we examined how metformin affects cell cycle arrest and apoptosis in cervical cancer cells. Western blot analysis showed that levels of O-linked N-acetylglucosamine (O-GlcNAc) and O-GlcNAc transferase (OGT) were increased in cervical cancer cells; these effects were reversed by metformin treatment. Immunoprecipitation analysis was used to examine the interplay between O-GlcNAcylation and phosphorylation in HeLa cells, revealing that metformin decreased O-GlcNAcylated AMP-activated protein kinase (AMPK) and increased levels of phospho-AMPK compared to untreated cells. These results were associated with decreased cell cycle arrest and apoptotic cell death in HeLa cells, as shown by flow cytometry. Moreover, 6-diazo-5-oxo-L-norleucine (a glutamine fructose-6-phosphate aminotransferase inhibitor) or thiamet G (an O-GlcNAcase inhibitor) decreased or increased levels of O-GlcNAcylated AMPK, and increased or decreased levels of phosphorylated AMPK, respectively, suggesting that O-GlcNAc modification affects AMPK activation. Of note, we found that metformin treatment of HeLa cells increased the levels of p21 and p27 (which are AMPK-dependent cell cycle inhibitors), leading to increased cell cycle arrest and apoptosis in HeLa cells compared to untreated cells. These findings suggest that metformin may serve as a useful antiproliferative drug in cervical cancer cells, with potential therapeutic benefit.

Angiopoietin-1 and -2 and vascular endothelial growth factor expression in ovarian grafts after cryopreservation using two methods.

OBJECTIVE: The favored method of preserving fertility in young female cancer survivors is cryopreservation and autotransplantation of ovarian tissue. Reducing hypoxia until angiogenesis takes place is essential for the survival of transplanted ovarian tissue. The aim of this study was to investigate the role of angiopoietin-1 (Angpt-1), angiopoietin-2 (Angpt-2), and vascular endothelial growth factor (VEGF) in ovarian tissue grafts that were cryopreserved using two methods. METHODS: Ovarian tissues harvested from ICR mice were divided into three groups: group I (control), no cryopreservation; group II, vitrification in EFS (ethylene-glycol, ficoll, and sucrose solution)-40; and group III, slow freezing in dimethyl sulfoxide. We extracted mRNA for VEGF, Angpt-1, and Angpt-2 from ovarian tissue 1 week following cryopreservation and again 2 weeks after autotransplantation. We used reverse transcriptase-polymerase chain reaction to quantify the levels of VEGF, Angpt-1, and Angpt-2 in the tissue. RESULTS: Angpt-1 and Angpt-2 expression decreased after cryopreservation in groups II and III. After autotransplantation, Angpt-1 and Angpt-2 expression in ovarian tissue showed different trends. Angpt-1 expression in groups II and III was lower than in group I, but Angpt-2 in groups II and III showed no significant difference from group I. The vitrified ovarian tissues had higher expression of VEGF and Angpt-2 than the slowfrozen ovarian tissues, but the difference was not statistically significant. CONCLUSION: Our results indicate that Angpt-2 may play an important role in ovarian tissue transplantation after cryopreservation although further studies are needed to understand its exact function.

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.

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.

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.