Simultaneous submission of seven CTSA proposals: UM1, K12, R25, T32-predoctoral, T32-postdoctoral, and RC2: strategies, evaluation, and lessons learned

Translation is the process of turning observations in the research laboratory, clinic, and community into interventions that improve people's health. The Clinical and Translational Science Awards (CTSA) program is a National Center for Advancing Translational Sciences (NCATS) initiative to advance translational science and research. Currently, 64 "CTSA hubs" exist across the nation. Since 2006, the Houston-based Center for Clinical Translational Sciences (CCTS) has assembled a well-integrated, high-impact hub in Texas that includes six partner institutions within the state, encompassing ∼23,000 sq. miles and over 16 million residents. To achieve the NCATS goal of "more treatments for all people more quickly," the CCTS promotes diversity and inclusion by integrating underrepresented populations into clinical studies, workforce training, and career development. In May 2023, we submitted the UM1 application and six "companion" proposals: K12, R25, T32-Predoctoral, T32-Postdoctoral, and RC2 (two applications). In October 2023, we received priority scores for the UM1 (22), K12 (25), T32-Predoctoral (20), and T32-Postdoctoral (23), which historically fall within the NCATS funding range. This report describes the grant preparation and submission approach, coupled with data from an internal survey designed to assimilate feedback from principal investigators, writers, reviewers, and administrative specialists. Herein, we share the challenges faced, the approaches developed, and the lessons learned.

[Comparison of tolerance to decentration and tilt in the early postoperative period between the continuous range and bifocal intraocular lens implantation in myopic eyes]

Objective: To compare decentration and tilt tolerances between continuous range intraocular lens (IOL) and bifocal IOL in myopia during the early stages post intraocular implantation. Method: A retrospective cohort study was conducted using follow-up data of 145 patients (145 eyes) who underwent phacoemulsification combined with IOL implantation in the Eye & ENT Hospital of Fudan University from January 2018 to December 2020. According to whether the axial length was less than 24.5 mm, patients were divided into non-myopic and myopic groups. According to IOL type, patients were divided into extend depth of focus (EDOF) ZXR00 IOL group (myopic 38 eyes, non-myopic 41 eyes) and bifocal ZMB00 IOL group (myopic 23 eyes, non-myopic 43 eyes). The distance and near visual acuity (log of the minimum angle of resolution visual acuity), IOL tilt and decentration, intraocular high-order aberration (HOA), coma, trefoil, spherical aberrations, modulation transfer function (MTF), as well as VF-14 index and the incidence of dysphotopsia were compared between the 2 groups at 3 months after surgery. Statistics were performed using Student's t-test, χ² test, Pearson correlation analysis and multiple linear regression analysis. Results: In either the myopic or non-myopic group, no significant differences were found in age, gender, eye laterality, axial length and IOL degree between eyes with the two different types of IOLs (all P>0.05). At 3 months after surgery, there was no significant difference in uncorrected and best-corrected distance visual acuity between the ZXR00 IOL group and the ZXR00 IOL group, while uncorrected near visual acuity was better in the ZMB00 IOL group than the ZXR00 IOL group (t=10.41, P<0.01). The total postoperative IOL decentration in the ZXR00 IOL group and ZMB00 IOL group in myopic eyes were (0.32±0.17) and (0.38±0.16) mm, respectively, which were greater than those in non-myopic eyes [(0.22±0.12), (0.28±0.12) mm; t=3.16, 2.57; both P<0.05]. However, there were no significant differences in IOL tilt between myopic and non-myopic eyes in the 2 groups (both P>0.05). There were no significant differences in postoperative IOL tilt and decentration between the 2 groups regardless of myopia or non-myopia (all P>0.05). In myopic eyes, HOA, coma aberration and spherical aberration in the ZXR00 IOL group were significantly lower than those in the ZMB00 IOL group, while the total ocular MTF (38.15±10.12) was significantly higher than that in the ZMB00 IOL group (30.46±10.53) (all P<0.05). Pearson correlation analysis and multiple linear regression analysis showed a positive correlation between postoperative HOA and both IOL tilt and decentration in the ZMB00 IOL group (r=0.627, 0.726; β=0.446, 0.587; all P<0.01). However, no such relationship was found in the ZXR00 IOL group (all P>0.05). In myopic eyes, when the IOL tilt aberration and decentration were greater than the median, the HOAs in the ZXR00 IOL group [(0.33±0.14), (0.27±0.11) μm] were lower than those in the ZMB00 IOL group [(0.88±0.56), (0.96±0.45) μm], while the total ocular MTF (42.87±10.97, 40.22±9.30) were higher than those in the ZMB00 IOL group (25.02±8.99, 29.87±10.19) (all P<0.05). In myopic eyes, the proportion of patients with visual interference symptoms in the ZXR00 IOL group [42.11% (16/38)] was significantly lower than that in the ZMB00 IOL group [78.26%(18/23), χ²=7.59, P<0.05]. Conclusion: During the early stages after IOL implantation in myopic eyes, EDOF IOL is more tolerant to decentration and tilt than bifocal IOL.

SARS-CoV-2 seroprevalence and antibody trends in vaccinated, multi-ethnic healthcare employees

Understanding of antibody kinetics against SARS-CoV-2 and its vaccines is rapidly evolving. This study aims to (1) determine post-vaccination seroprevalence; (2) compare antibody levels between vaccine types and various clinical/demographic determinants; and (3) determine post-vaccination antibody concentrations against time. This is a retrospective cross-sectional study involving 148 healthcare employees all over Malaysia. IgG Spike (RBD), IgM Spike and IgG Nucleocapsid concentration medians were compared using Mann-Whitney U or Kruskal-Wallis tests. Chi Square and Spearman correlation coefficient tests were performed to identify variables associated with antibody titers. A scatter plot of IgG Spike (RBD) against time from last vaccine dose was also plotted. At 1-month post-vaccination, all employees successfully seroconverted regardless of vaccine type, health status and COVID- 19 history. Comirnaty, convalescent, female or Malay vaccinees had significantly higher IgG Spike (RBD) titers compared to their respective counterparts. No correlation was found between age and IgG Spike (RBD) levels. Concentration of all three antibodies waned with time post-vaccination, with IgM Spike and IgG Nucleocapsid waning faster than IgG Spike (RBD).

Effects of Pre-Existing Liver Disease on Acute Pain Management Using Patient-Controlled Analgesia Fentanyl With Parecoxib After Major Liver Resection: A Retrospective, Pragmatic Study

BACKGROUND

The aim of this study was to compare the outcomes of pain management with the use of patient-controlled analgesia (PCA) fentanyl with IV parecoxib between patients with healthy liver with patients with diseased liver undergoing major liver resection.

METHODS

Patients with healthy liver undergoing partial hepatectomy as liver donors for liver transplantation (group 1) and patients with liver cirrhosis (Child's criteria A) undergoing major liver resection for hepatoma (group 2) were identified retrospectively. Both groups routinely received post-operative IV PCA fentanyl and a single dose of parecoxib 40 mg. They were followed up for 3 days or until PCA fentanyl was discontinued post-operatively. Daily Visual Analog Scale, PCA fentanyl usage, rescue attempts, and common drug side effects were collected and analyzed with the use of SPSS version 20.

RESULTS

One hundred one patients were included in the study: 54 in group 1, and 47 in group 2. There were no statistical differences between the two groups in terms of the daily and total fentanyl usage, VAS resting, and incidence of itchiness. The rate of rescue analgesia on post-operative day (POD) 1 was lower in group 2, with a value of P = .045. VAS dynamics were better on POD 1 and 2 for group 2, with P = .05 and P = .012, respectively.

CONCLUSIONS

We found that combining a single dose of IV parecoxib 40 mg with PCA fentanyl is an easy and effective method of acute pain control after major liver resection. We propose the careful usage of post-operative fentanyl and parecoxib in patients with diseased liver, given the difference in effect as compared with healthy liver.

What are the Needs of Students? An Experience from a District Based Health Promoting Schools Project in Hong Kong

A district based needs assessment as conducted over the past year to uderstand the health problems and the health education needs of the students in Tai Po district, Hong ong. 6879 primary one to primary six students from eighteen rimary schools, participating in a district based Health Promoting Schools Project in Hong Kong, were invited to complete a self-administrated questionnaire which was partly adapted from the Centre for Diseases and Control (CDC)'s Youth Risk Behaviour Surveillance Survey. The results presented a holistic picture of the health and needs of primary students with respect to their general health status, mental health, body weight and dietary behaviour, exercise, preventive health care, tobacco use, alcohol and other drug use, school environment and school health education. It provides baseline information for the project to prioritize the problems and strategically plan health promotion 'programmes with reference to the concept of Health Promoting Schools by the World Health Organization.

Correlation Between Changes in End-Tidal Carbon Dioxide Concentration and Cardiac Output During Inferior Vena Cava Clamping and Unclamping in Living-donor Liver Transplantation

BACKGROUND

To test the hypothesis that low end-tidal carbon dioxide tension encountered during anhepatic phase in liver transplantation is related to hemodynamic status rather than ventilatory status, and can be used to predict the change in cardiac output during anhepatic phase.

METHODS

We retrospectively analyzed and compared data, included end-tidal carbon dioxide tension (ETCO2), arterial blood pressure, heart rate, central venous pressure, cardiac output, cardiac index, and stroke volume, before and after inferior vena cava clamping, and 0, 5, 10, 30 minutes during the anhepatic, and 5 minutes after the release of IVC cross clamp during the reperfusion phase, with paired Student t test, repeated measurement, and linear regression. P < .05 was regarded as significant.

RESULTS

The cardiac output and ETCO2 decrease significantly after clamping the inferior vena cava and increase concomitantly after unclamping. There is a positive correlation between the changes in % in cardiac output and ETCO2 (Pearson coefficient r = 0.741).

CONCLUSION

The changes in ETCO2 can be used to predict the changes of the cardiac output in % when cardiac output monitoring is not available. Before unclamping of the IVC, mild hyperventilation is suggested to prevent excessive increase in PaCO2.

Knockdown of RAB25 promotes autophagy and inhibits cell growth in ovarian cancer cells

RAB25 belongs to the Rab family of small GTPases and is implicated in the development of various types of human cancer. To evaluate the role of RAB25 in ovarian cancer, RAB25 was knocked down by siRNA in HEY and ES‑2 human ovarian cancer cells. Autophagy, cell growth and cell apoptosis were evaluated. The results showed that knockdown of RAB25 increased acidic vesicle organelles and GFP-microtubule-associated protein 1 light chain 3 punctate fluorescence in ovarian cancer cells. Autophagy that promoted by knockdown of RAB25 was not observed in cells where the ERK1/2 signaling pathway had been inhibited by U0126. Knockdown of RAB25 reduced cell cycle progression and cell growth. Apoptosis of ovarian cancer cells could be induced by knockdown of RAB25. These results support the tumorigenic role of RAB25 in ovarian cancer cells.

Rab25 increases cellular ATP and glycogen stores protecting cancer cells from bioenergetic stress

Cancer cells are metabolically stressed during tumour progression due to limited tumour vascularity and resultant nutrient, growth factor and oxygen deficiency that can induce cell death and inhibit tumour growth. We demonstrate that Rab25, a small GTPase involved in endosomal recycling, that is genomically amplified in multiple tumour lineages, is a key regulator of cellular bioenergetics and autophagy. RAB25 enhanced survival during nutrient stress by preventing apoptosis and autophagy via binding and activating AKT leading to increased glucose uptake and improved cellular bioenergetics. Unexpectedly, Rab25 induced the accumulation of glycogen in epithelial cancer cells, a process not previously identified. Strikingly, an increase in basal ATP levels combined with AKT-dependent increases in glucose uptake and glycogen storage allowed maintenance of ATP levels during bioenergetic stress. The clinical relevance of these findings was validated by the ability of a Rab25-dependent expression profile enriched for bioenergetics targets to identify patients with a poor prognosis. Thus, Rab25 is an unexpected regulator of cellular bioenergetics implicated as a useful biomarker and potential therapeutic target.

P4-05-01: Rab25 Alters Cellular Energetics and Growth Signaling during Breast Oncogenesis

Background: Conservation and consumption of cellular energy is centrally regulated by growth and metabolism of the whole organism. The cancer cell gains autonomy from this regulation to become an organism with indeterminate growth potential. Plasma membrane receptors including growth factors and nutrient receptors are sensors for microenvironmental cues that dictate the intracellular energetic pathways to recalibrate ATP production based on available resources. So altercations in both growth and metabolic pathways are common features of cancers. A unifying component between receptor mediated growth signaling and metabolic pathways within a cell could be the vesicular trafficking system that imports, transports and exports a wide array of cargo from both these pathways.

In fact, derailed endocytosis is a hallmark of cancer. The endocytic pathway, as demonstrated by our laboratory, is a frequent target of genomic aberrations in cancer, and plays a critical role in maintenance of cellular polarity, stem cell fnction, bioenergetics, proliferation, motility, invasion, metastasis, apoptosis and autophagy. The Rab GTPases along with their effectors are critical regulators of this endocytic machinary and can have a huge impact on the cellular iterinary of growth and metabolism.

Methods and results: A broad spectrum analysis of distribution of all the Rab family members across 52 breast cancer cell lines reflected a dichotomous distribution of Rab25, with higher mRNA and protein expression in ER+ cell lines. Rab 25 is of immense interest to us because of its unique substitution of leucine for glutamine at position 71which typically decreases the intrinsic GTPase activity, resulting in a dominant, constitutively active protein, akin to a transforming RAS mutation.

Using high throughput mRNA data analysis, we report that Rab25 and its effector Rab Coupling Protein (RCP) are frequently coamplified and coordinately elevated in ER +ve breast cancers. Specifically in the luminal B subtypes, they are significantly associated with a markedly worsened outcome. In vitro, in MCF7 cell line, we observe an increased EGFR stability and MAPK signaling in Rab25 overexpressing stable clones which could be reversed with shRNA knockdown of Rab25. Loss of either Rab25 or RCP inhibited survival and growth of MCF7 lines under serum free conditions suggesting that Rab25 can potentially facilitate growth factor independence in cancer cells. Most importantly, we report that Rab25 enhances mitochondrial ATP production in breast and ***ovarian cancer cells and significantly reduces acidification of the ECM. Our ongoing experiments are directed towards understanding the mechanistic link between Rab25 mediated effects on EGFR/pERK signaling and its effects on cellular metabolism.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-05-01.

Dual inhibition of tumor energy pathway by 2-deoxyglucose and metformin is effective against a broad spectrum of preclinical cancer models

Tumor cell proliferation requires both growth signals and sufficient cellular bioenergetics. The AMP-activated protein kinase (AMPK) pathway seems dominant over the oncogenic signaling pathway suppressing cell proliferation. This study investigated the preclinical efficacy of targeting the tumor bioenergetic pathway using a glycolysis inhibitor 2-deoxyglucose (2DG) and AMPK agonists, AICAR and metformin. We evaluated the in vitro antitumor activity of 2DG, metformin or AICAR alone, and 2DG in combination either with metformin or AICAR. We examined in vivo efficacy using xenograft mouse models. 2DG alone was not sufficient to promote tumor cell death, reflecting the limited efficacy showed in clinical trials. A combined use of 2DG and AICAR also failed to induce cell death. However, 2DG and metformin led to significant cell death associated with decrease in cellular ATP, prolonged activation of AMPK, and sustained autophagy. Gene expression analysis and functional assays revealed that the selective AMPK agonist AICAR augments mitochondrial energy transduction (OXPHOS) whereas metformin compromises OXPHOS. Importantly, forced energy restoration with methyl pyruvate reversed the cell death induced by 2DG and metformin, suggesting a critical role of energetic deprivation in the underlying mechanism of cell death. The combination of 2DG and metformin inhibited tumor growth in mouse xenograft models. Deprivation of tumor bioenergetics by dual inhibition of energy pathways might be an effective novel therapeutic approach for a broad spectrum of human tumors.

FSH inhibits ovarian cancer cell apoptosis by up-regulating survivin and down-regulating PDCD6 and DR5

Ovarian epithelial cancer is the leading cause of death among gynecological malignancies. FSH may increase the risk of ovarian malignancy and play an important role in ovarian carcinogenesis. Our previous studies showed that FSH increases the expression of VEGF through survivin. In this study, the function and mechanism of FSH in ovarian cancer were further explored. We found that FSH promoted proliferation and prevented apoptosis of ovarian cancer cells by activating survivin through the SAPK/JNK and PI3K/AKT pathways. FSH also down-regulated the expression of programmed cell death gene 6 (PDCD6) and death receptor 5 (DR5), two molecules required for induction of apoptosis. RNA interference was applied to knock down survivin and PDCD6 expression, and we found that the blockage of survivin reversed the effects of FSH on apoptosis and proliferation, whereas knock down of PDCD6 enhanced these effects. The expression of DR5, cyclin D1, and cyclin E correlated with survivin expression, but PDCD6 did not. Using immunohistochemical staining, we further showed that ovarian serous cystadenocarcinoma samples had higher expression of survivin than did benign ovarian cystadenoma and borderline cystadenoma samples (P<0.01). Furthermore, survivin expression in the ovarian serous cystadenocarcinoma specimens was correlated with disease stage (P<0.05). Our results suggest that FSH promotes ovarian cancer development by regulating the expression of survivin, PDCD6, and DR5. Greater understanding of the molecular mechanisms of FSH in ovarian epithelial carcinogenesis and development will ultimately help in the development of a novel targeted therapy for ovarian cancer.

Genomic and proteomic approaches identify Rab25 as a potential prognostic marker for luminal B breast tumors

Estrogen receptor (ER) +ve luminal B subtype of breast tumors initially respond well to tamoxifen treatment. However, over longer periods of time, their frequent recurrence contributes to the overall high mortality rate of hormone receptor +ve breast cancer patients. Recently, with the development of PARP inhibitors, there is a potential line of treatment for the triple negative subtype. But a huge dearth exists in therapeutically targeting luminal B tumors since these tumors are also insensitive to chemotherapy. Our current research addresses this urgent need by utilizing a systems biology approach to identify potential therapeutic targets and diagnostic markers for luminal B subtype of breast cancer.

The endocytic pathway, as demonstrated by our laboratory is a frequent target of genomic aberrations in cancer, and plays a critical role in maintenance of cellular polarity, stem cell function, bioenergetics, proliferation, motility, invasion, metastasis, apoptosis and autophagy. Derailed endocytosis is therefore a hallmark of cancer. The Rab GTPases along with their effectors are critical regulators of this endocytic machinery and can have a huge impact on the cellular itinerary of growth factor as well as integrin receptor signaling. A broad spectrum analysis of distribution of all the Rab family members across 52 breast cancer cell lines reflected a dichotomous distribution of Rab25, with higher mRNA and protein expression in ER+ cell lines. Rab 25 is of immense interest to us because of its unique substitution of leucine for glutamine at position 71 which typically decreases the intrinsic GTPase activity, resulting in a dominant, constitutively active protein, akin to a transforming RAS mutation. Here we evaluate the role of Rab25 as a valuable predictive and prognostic marker for ER+ breast cancers, with critical implication in disease management and predicting response to therapy.

Using high throughput data analysis from publicly available mRNA expression datasets, we report that Rab25 and its effector Rab coupling protein (RCP) are frequently coamplified and coordinately elevated in ER +ve breast cancers. Specifically in the luminal B subtypes, they are significantly associated with a markedly worsened outcome. Compatible with Rab25 and RCP being drivers of the amplicons, their respective mRNA levels are highly correlated across multiple tumor sets, most prominently in luminal B tumors (Soritiou p&lt;0.0015; Pawitan p&lt;0.01). Patients with low RNA levels of both Rab25 and RCP have a very good outcome, those with high level of either Rab25 or RCP have an intermediate outcome and patients with coordinate elevation of Rab25 and RCP mRNA have a bad outcome. Additionally, using our Reverse Phase Protein Array (RPPA) technology, we found that at protein level Rab25 and RCP correlate with poorer outcome in luminal B tumors. In vitro, using MCF7 cell line, which is a prototype of luminal B subtype, we observed an altered EGFR stability and signaling in Rab25 overexpressing stable clones which could be rescued with shRNA knock-down of Rab25, confirming specificity of Rab25 action. In MCF7 cells overexpressing Rab25, we found higher proliferation index as well as increased cell migration and invasion potentials. When injected as xenografts in mice, Rab25 overexpressing cells formed larger tumors than their wildtype controls, strongly suggesting a role for Rab25 in promoting tumor progression in luminal B tumors. The proposed studies will have a marked impact on our understanding of the mechanisms by which Rab25 and RCP contribute to breast cancer aggressiveness, and also of the therapeutic and clinical potential of Rab25 and the Rab25: RCP complex as a target and marker of the behavior of breast tumors.

Color variation in periodic Ag line arrays patterned by using electron-beam lithography

Periodic Ag line arrays with different line pitches from 500 nm to 950 nm on ITO coated glass substrates have been fabricated by using electron-beam lithography (EBL) technique for studying the color light guide in a display system. The patterned Ag line array is used as a light outcoupling and color-selection component due to the emission wavelength changed by the Ag line arrays with different periodic distances that could achieve color variation. We have demonstrated that the ITO coated glass substrates containing periodic Ag line arrays with varied line pitches can be used as a color filter in a display device. This means that with a proper metallic nanostructure layer, the red, green, and blue colors in a display system can be obtained without a traditional color filter for modern multi-applications of optoelectronic display devices.

Effects of hemorrhagic shock in early and late partial posthepatectomy rats

INTRODUCTION

The purpose of the study was to determine the compensatory function of the remnant liver as a blood reservoir after 70% hepatectomy in rats to counteract hemorrhagic shock and reperfusion.

METHODS AND MATERIALS

One hour of hemorrhagic shock followed by 1 hour of resuscitation induced in normal rats (group I) was compared with animals that had undergone 70% hepatectomy at postoperative day 3 (group II) and day 7 (group III). We compared the total blood loss, the blood pressure before hemorrhagic shock, hemoglobin, hemotocrit, and mortality. Liver function such as aspartate transferase (AST), alanine transferase, and lactate dehydrogenase (LDH) were also compared among groups by one-way analysis of variance with post hoc correction. A P value less than .05 was regarded as significant.

RESULTS

The results showed a lower volume of drawn blood induced hemorrhagic shock in group II compared with group I or group III hosts. The blood loss was 15.6+/-1.0, 5.68+/-2.5, and 13.2+/-1.6 mL for groups I, II, and III, respectively. The mortality due to hemorrhagic shock was significantly higher in group II compared with group I or group III. Liver function tests showed that the AST and LDH were significantly higher after resuscitation in group II.

CONCLUSION

In the early postoperative period (day 3) after 70% hepatectomy, rats were more vulnerable to a high mortality after hemorrhagic shock compared with hosts in the late postoperative period (day 7). Significantly higher AST and LDH in group II indicated that the remnant liver was more injured after hemorrhagic shock in the early postoperative period.

The emerging role of the RAB25 small GTPase in cancer

RAB25, a member of the rat sarcoma (RAS) family of small GTPase, has been implicated in the pathophysiology of ovarian, breast and other cancers. Its role in endosomal transport and recycling of cell-surface receptors and signaling proteins presents a novel paradigm for the disruption of cellular pathways and promotion of tumor development and aggressiveness. Variations in structure and post-translational modifications control the localization of RAS superfamily proteins to specific subcellular compartments and recruitment of downstream effectors, allowing these small GTPases to function as sophisticated modulators of a complex and diverse range of cellular processes. Here, we review the link between RAB25 and tumor development and current knowledge regarding its possible roles in cancer.

Rab25 associates with alpha5beta1 integrin to promote invasive migration in 3D microenvironments

Here, we report a direct interaction between the beta1 integrin cytoplasmic tail and Rab25, a GTPase that has been linked to tumor aggressiveness and metastasis. Rab25 promotes a mode of migration on 3D matrices that is characterized by the extension of long pseudopodia, and the association of the GTPase with alpha5beta1 promotes localization of vesicles that deliver integrin to the plasma membrane at pseudopodial tips as well as the retention of a pool of cycling alpha5beta1 at the cell front. Furthermore, Rab25-driven tumor-cell invasion into a 3D extracellular matrix environment is strongly dependent on ligation of fibronectin by alpha5beta1 integrin and the capacity of Rab25 to interact with beta1 integrin. These data indicate that Rab25 contributes to tumor progression by directing the localization of integrin-recycling vesicles and thereby enhancing the ability of tumor cells to invade the extracellular matrix.

Religious coping and problem-solving by couples faced with prostate cancer

Religion can be an important resource for people struggling with chronic illness. Problem-solving skills have also been shown to be helpful. This study examined whether turning to religion as a coping resource would be associated with better problem-solving in couples trying to manage challenges associated with prostate cancer. The sample was 101 patients with prostate cancer and their wives. Wives completed the Social Problem-Solving Inventory--Revised at baseline (T1) and 10 weeks later (T2). Patients and their wives also completed a measure that included items on religious coping. These items were used to classify couples into four groups based on whether one or both members engaged in religious coping: (1) husband only, (2) wife only, (3) both husband and wife, and (4) neither husband nor wife. From T1 to T2, wives who used religious coping along with their husbands (group 3) showed a significantly greater reduction in dysfunctional problem-solving (specifically, on impulsive/careless problem-solving) in comparison with wives who used religious coping while their husbands did not (group 2). Findings suggest that when couples share in turning to religion as a source of coping, this may be associated with improved problem-solving, but sole engagement in religious coping by wives may be associated with worse problem-solving.

Amplification of MDS1/EVI1 and EVI1, located in the 3q26.2 amplicon, is associated with favorable patient prognosis in ovarian cancer

Increased copy number involving chromosome 3q26 is a frequent and early event in cancers of the ovary, lung, head and neck, cervix, and BRCA1 positive and basal breast cancers. The p110alpha catalytic subunit of phosphoinositide-3-kinase (PI3KCA) and protein kinase Ciota (PKCiota) have previously been shown as functionally deregulated by 3q copy number increase. High-resolution array comparative genomic hybridization of 235 high-grade serous epithelial ovarian cancers using contiguous bacterial artificial chromosomes across 3q26 delineated an approximately 2 Mb-wide region at 3q26.2 encompassing PDCD10 to MYNN (chr3:168722613-170908630). Ecotropic viral integration site-1 (EVI1) and myelodysplastic syndrome 1 (MDS1) are located at the center of this region, and their DNA copy number increases are associated with at least 5-fold increased RNA transcript levels in 83% and 98% of advanced ovarian cancers, respectively. Moreover, MDS1/EVI1 and EVI1 protein levels are increased in ovarian cancers and cancer cell lines. EVI1 and MDS1/EVI1 gene products increased cell proliferation, migration, and decreased transforming growth factor-beta-mediated plasminogen activator inhibitor-1 promoter activity in ovarian epithelial cells. Intriguingly, the increases in EVI1 DNA copy number and MDS1/EVI1 transcripts are associated with improved patient outcomes, whereas EVI1 transcript levels are associated with a poor patient survival. Thus, the favorable patient prognosis associated with increased DNA copy number seems to be as a result of high-level expression of the fusion transcript MDS1/EVI1. Collectively, these studies suggest that MDS1/EVI1 and EVI1, previously implicated in acute myelogenous leukemia, contribute to the pathophysiology of epithelial ovarian cancer.

Atypical PKCiota contributes to poor prognosis through loss of apical-basal polarity and cyclin E overexpression in ovarian cancer

We show that atypical PKCiota, which plays a critical role in the establishment and maintenance of epithelial cell polarity, is genomically amplified and overexpressed in serous epithelial ovarian cancers. Furthermore, PKCiota protein is markedly increased or mislocalized in all serous ovarian cancers. An increased PKCiota DNA copy number is associated with decreased progression-free survival in serous epithelial ovarian cancers. In a Drosophila in vivo epithelial tissue model, overexpression of persistently active atypical PKC results in defects in apical-basal polarity, increased Cyclin E protein expression, and increased proliferation. Similar to the Drosophila model, increased PKCiota proteins levels are associated with increased Cyclin E protein expression and proliferation in ovarian cancers. In nonserous ovarian cancers, increased PKCiota protein levels, particularly in the presence of Cyclin E, are associated with markedly decreased overall survival. These results implicate PKCiota as a potential oncogene in ovarian cancer regulating epithelial cell polarity and proliferation and suggest that PKCiota is a novel target for therapy.

Assay of Rab25 function in ovarian and breast cancers

There is a multitude of critical steps during the pathogenesis of cancer that allow cells to acquire the ability to escape from normal controls on cell growth, to avoid programmed cell death, and to become malignant. Here, we describe a molecular approach that can be broadly applied to identify drivers of genomic aberrations in cancer development. In the process, areas of genomic aberrations and genes that are dysregulated by genomic amplification are identified by array comparative genomic hybridization (CGH) and transcription profiling, respectively, with major emphasis on coordinating amplification at the CGH and RNA level and on correlation with patient's outcomes. Once candidate genes are identified, we perform functional genomics by manipulating levels in normal and tumor cells using RNAi or transfection, and assessing a battery of cellular functions including proliferation, anti-apoptosis, loss of contact inhibition, changes in cell signaling or transcriptional profiles, anchorage-independent growth, and in vivo tumor growth. We have successfully used this approach to identify the RAB25 gene that has been implicated in the progression and aggressiveness of ovarian and breast cancers.

The RAB25 small GTPase determines aggressiveness of ovarian and breast cancers

High-density array comparative genomic hybridization (CGH) showed amplification of chromosome 1q22 centered on the RAB25 small GTPase, which is implicated in apical vesicle trafficking, in approximately half of ovarian and breast cancers. RAB25 mRNA levels were selectively increased in stage III and IV serous epithelial ovarian cancers compared to other genes within the amplified region, implicating RAB25 as a driving event in the development of the amplicon. Increased DNA copy number or RNA level of RAB25 was associated with markedly decreased disease-free survival or overall survival in ovarian and breast cancers, respectively. Forced expression of RAB25 markedly increased anchorage-dependent and anchorage-independent cell proliferation, prevented apoptosis and anoikis, including that induced by chemotherapy, and increased aggressiveness of cancer cells in vivo. The inhibition of apoptosis was associated with a decrease in expression of the proapoptotic molecules, BAK and BAX, and activation of the antiapoptotic phosphatidylinositol 3 kinase (PI3K) and AKT pathway, providing potential mechanisms for the effects of RAB25 on tumor aggressiveness. Overall, these studies implicate RAB25, and thus the RAB family of small G proteins, in aggressiveness of epithelial cancers.

Analysis of Molecular Aberrations in Ovarian Cancer Allows Novel Target Identification

The completion of the Human Genome Project and recent advances in functional genomic, proteomic, and high-throughput screening methodologies have provided powerful tools for determining the mechanisms of human diseases, including complex polygenic diseases such as ovarian cancer. These developments may eventually lead to individualized molecular medicine, which is the treatment of patients based on the underlying genetic defects in their tumours and their own genetic makeup. A plethora of novel therapeutic agents that act on specific molecular targets defined by cancer genetics are under development. There is thus a great deal of interest in determining how specific genes and proteins function in cancers, in order to further the understanding of cancer initiation and progression; to aid in identifying biomarkers, therapeutic targets, and determinants of drug responsiveness; and to progress the development of novel antitumour agents.

Active finite element analysis of skeletal muscle-tendon complex during isometric, shortening and lengthening contraction

An active finite element model was developed to predict the mechanical behaviors of skeletal muscle-tendon complex during isometric, shortening and lengthening contraction. The active finite element was created through incorporation of a user-defined material property into ABAQUS finite element code. The active finite element is controlled by a motor element that is activated by a mathematical function. The nonlinear passive behavior of the muscle was defined by the viscoelastic elements and can be easily altered to other properties by using other elements in the material library without the need of re-defining the constitutive relation of the muscle. The isometric force-length relationship, force-strain relations of the muscle-tendon complex during both shortening and lengthening contraction and muscle relaxation response were predicted using the proposed finite element model. The predicted results were found to be in good agreement with available experimental data. In addition, the stress distribution in the muscle-tendon complex during isometric, shortening and lengthening contractions was simulated. The location of the maximum stress may provide useful information for studying muscle damage and fatigue in the future.

Welded tracheal stent removal in a child under cardiopulmonary bypass

Metallic tracheal stents have been used in the treatment of paediatric tracheomalacia for more than a decade. We describe a case in which critical airway obstruction occurred during removal of a welded tracheal stent using a rigid bronchoscope under general anaesthesia. Life-saving cardiopulmonary bypass was instituted urgently, and the welded stent was then removed successfully by directly opening the trachea.

Identification of a phosphothionate analogue of lysophosphatidic acid (LPA) as a selective agonist of the LPA3 receptor

Lysophosphatidic acid (LPA) is a bioactive lysophospholipid mediator that acts through G protein-coupled receptors. Most cell lines in culture express one or more LPA receptors, making it difficult to assign a response to specific LPA receptors. Dissection of the signaling properties of LPA has been hampered by lack of LPA receptor subtype-specific agonists and antagonists. The present study characterizes an ester-linked thiophosphate derivative (1-oleoyl-2-O-methyl-rac-glycerophosphothionate, OMPT) of LPA. OMPT is a functional LPA analogue with potent mitogenic activity in fibroblasts. In contrast to LPA, OMPT does not couple to the pheromone response through the LPA(1) receptor in yeast cells. OMPT induces intracellular calcium increases efficiently in LPA(3) receptor-expressing Sf9 cells but poorly in LPA(2) receptor-expressing cells. Guanosine 5'-O-(3-[(35)S]thio)triphosphate binding assays in mammalian cells showed that LPA exhibits agonistic activity on all three LPA receptor subtypes, whereas OMPT has a potent agonistic effect only on the LPA(3) receptor. In transiently transfected HEK293 cells, OMPT stimulates mitogen-activated protein kinases through the LPA(3) but not the LPA(1) or LPA(2) receptors. Furthermore, OMPT-induced intracellular calcium mobilization in mammalian cells is efficiently inhibited by the LPA(1)/LPA(3) receptor-selective antagonist VPC12249. These results establish that OMPT is an LPA(3)-selective agonist. OMPT binding to the LPA(3) receptor in mammalian cells is sufficient to elicit multiple responses, including activation of G proteins, calcium mobilization, and activation of mitogen-activated protein kinases. Thus OMPT offers a powerful probe for the dissection of LPA signaling events in complex mammalian systems.

Human chorionic gonadotropin-activated cAMP pathway regulates human placental GnRH receptor gene transcription in choriocarcinoma JEG-3 cells

A dose- and time-dependent increase in the human GnRH receptor (GnRHR) promoter activity after forskolin treatment was observed after transient transfection of human placental choriocarcinoma JEG-3 cells with a 2297-bp human GnRHR promoter-luciferase construct (p2300-LucF). This stimulatory effect was mimicked by administrating of cholera toxin, cAMP analog, or human chorionic gonadotropin. A specific adenylate cyclase inhibitor or protein kinase A inhibitor pretreatment reversed the forskolin- and human chorionic gonadotropin-induced increase in the human GnRHR promoter activity. Progressive 5' deletion assays identified a 412-bp fragment (-577 to -167) in the human GnRHR 5'-flanking region that is essential in maintaining the basal responsiveness to cAMP. Mutagenesis, coupled with functional studies, has identified two putative activating protein-1 (AP-1)/cAMP-responsive element (CRE) binding protein binding sites, namely human GnRHR (hGR)-AP/CRE-1 and hGR-AP/CRE-2, mediating the cAMP-stimulatory effect. Mutation of the putative hGR-AP/CRE-1 and hGR-AP/CRE-2 resulted in 32% and 35% decreases in the forskolin-induced stimulation, respectively. The binding of CRE binding protein to these motifs was confirmed by gel mobility shift assay and antibody supershift assay.

A population of oligodendrocytes derived from multipotent neural precursor cells expresses a cholinergic phenotype in culture and responds to ciliary neurotrophic factor

Because oligodendrocytes and their precursors possess receptors for classical transmitters, and neurotransmitters such as glutamate and noradrenaline can mediate oligodendroglial proliferation and differentiation, it is possible that other neurotransmitters can also exert regulatory roles in oligodendrocyte function. We used mitogen-proliferated multipotent neuroepithelial precursors (neurospheres) and identified oligodendroglia that expressed markers traditionally found in cholinergic neurons. Regardless of culture conditions, there existed a large population of cells that resembled oligodendrocytes morphologically and coexpressed the oligodendrocyte-specific marker galactocerebroside (GalC) and the acetylcholine (ACh)-synthesizing enzyme choline acetyltransferase (ChAT). These cells did not express neuronal markers, and whole-cell recordings from cells with similar morphology displayed only outward currents in response to depolarizing voltage steps, further supporting their oligodendroglial identity. Another cholinergic marker, the vesicular ACh transporter, was also detected in GalC(+) oligodendrocytes. Furthermore, neurospheres cultured in the presence of the cholinergic receptor antagonist atropine showed a decrease in the number of GalC(+) spheres, implicating the muscarinic ACh receptor in oligodendrocyte development. The actions of neurotrophins and ciliary neurotrophic factor (CNTF) on these ChAT(+) oligodendrocytes were examined. Among these, CNTF treatment significantly increased oligodendrocytic process outgrowth. These results demonstrate classical cholinergic neuronal markers in oligodendrocytes as well as an effect of muscarinic receptor blockade on oligodendrocyte differentiation.

Differential role of PR-A and -B isoforms in transcription regulation of human GnRH receptor gene

The presence of progesterone response element (PRE) in the 5'-flanking region of the human GnRH receptor (GnRHR) suggests the possible regulation of this gene by progesterone (P). In the present study, we examined the effects of P in transcriptional regulation of human GnRHR gene expression at the pituitary and placenta levels since the GnRHR has been detected in both tissues. By the use of transient transfection assays, a differential regulation of human GnRHR promoter activity by P was observed. P treatment resulted in a decrease in promoter activity in the pituitary alphaT3-1 cells, suggesting a P-mediated inhibitory action. Interestingly, P is found to have a stimulatory role at the placental expression of this gene. Addition of RU486 to, or inhibition of endogenous P production by, the placental JEG-3 cells leads to a decrease in promoter activity, which is reversed by the replacement of P. Further studies have identified a putative PRE, namely human GR-PRE (located between -535 and -521, related to translation start site), that may be responsible for the P action since the mutation of these motifs reversed the P-mediated effects. The binding of PR to this element is confirmed by antibody supershift assays. The physiological effects of P are mediated through two PR isoforms, namely PR-A and PR-B. In the present study, overexpression of human PR-A resulted in a decrease in human promoter activity in both pituitary and placental cells. Interestingly, overexpression of PR-B exhibits a cell-dependent transcriptional activity, whereby it functions as a transcription activator in the placenta but as a transcription repressor in the pituitary. In summary, our results demonstrated a differential usage of PR-A and PR-B in transcriptional regulation of human GnRHR gene expression by P at the pituitary and placenta levels.

The role of genetic abnormalities of PTEN and the phosphatidylinositol 3-kinase pathway in breast and ovarian tumorigenesis, prognosis, and therapy

Breast and ovarian cancers exhibit similar epidemiologic, genotypic, and phenotypic characteristics. Phosphatidylinositol 3-kinase (PI3K) and the PTEN tumor suppressor gene product phosphorylate and dephosphorylate the same 3' site in the inositol ring of membrane phosphatidylinositols. Germ-line mutations in the PTEN tumor suppressor gene are causative of Cowden's breast cancer predisposition syndrome, and PTEN is frequently mutated in sporadic breast cancers. In contrast, amplification of multiple components of the PI3K pathway is a hallmark of serous epithelial ovarian cancers. The resultant activation of the PI3K pathway in both breast and ovarian cancers contributes to cell-cycle progression, decreased apoptosis, and increased metastatic capabilities. Strikingly, both ovarian and breast cancer cells are selectively sensitive to pharmacologic and genetic manipulation of the PI3K pathway, making molecular therapeutics targeting this pathway particularly attractive approaches for these cancers.

Human gonadotropin-releasing hormone receptor gene transcription: up-regulation by 3',5'-cyclic adenosine monophosphate/protein kinase A pathway

Transient transfection of mouse gonadotrope-derived (alphaT3-1) cells with a 2297 bp human GnRHR promoter-luciferase construct (p2300-LucF) showed a dose- and time-dependent increase in the human gonodotropin-releasing hormone receptor (GnRHR) promoter activity after forskolin treatment. An average of 4.8-fold increase in promoter activity was observed after 12 h of 10 microM forskolin treatment. This effect was mimicked by administration of cholera toxin, cAMP analog or pituitary adenylate cyclase activating polypeptide 38 (PACAP). A specific adenylate cyclase (AC) inhibitor (ACI) or protein kinase A (PKA) inhibitor (PKAI) pretreatment reversed the forskolin- and PACAP-induced increase in the human GnRHR promoter activity. These results not only confirm the stimulatory effect of Cyclic adenosine monophosphate (cAMP) in human GnRHR promoter activation, but also suggest that hormones or neurotransmitters that activate adenylate cyclase in pituitary gonadotropes may increase the expression of human GnRHR gene in transcriptional level. Progressive 5' deletion assays identified a 412 bp fragment (-577 to 167) in the human GnRHR 5'-flanking region that is essential in maintaining the basal responsiveness to cAMP. Mutagenesis coupled with functional studies have identified two putative AP-1/CREB binding sites, namely hGR-AP/CRE-1 and hGR-AP/CRE-2 that participated in mediating the cAMP-stimulatory effect. Mutation of the putative hGR-AP/CRE-1 and hGR-CRE-2 resulted in a 38 and 32% decrease in the forskolin-induced stimulation. However, mutation of both binding sites did not completely abolish the cAMP-stimulatory effect, suggesting that multiple transcription factor binding sites were involved in full response in cAMP stimulation. The binding of CREB to these motifs was confirmed by gel mobility shift assay and antibody supershift assay.

Functional mapping of a placenta-specific upstream promoter for human gonadotropin-releasing hormone receptor gene

GnRH has been showed to regulate hCG expression and secretion from the placenta through a GnRH receptor (GnRHR)-mediated process. Recently, we have reported the isolation of human GnRHR full-length complementary DNA from the human placental cells including choriocarcinoma JEG-3 cells, immortalized extravillous trophoblasts, and primary cultures of trophoblasts. Despite these observations, the molecular mechanism that controls the transcription regulation of the GnRHR gene expression in the placenta remains unknown. Here we described the identification of an upstream placenta-specific promoter located between nucleotide (nt) -1737 and -1346 (relative to the translation start site) for the human GnRHR gene. Using transient transfection studies, this upstream promoter has been shown to determine the placental cell-specific expression of this gene. Primer extension studies further confirmed the utilization of this promoter in JEG-3 cells in vivo. By mutagenesis coupled to functional studies, we have identified four putative transcription factor-binding sites, namely human glucocorticoid receptor (hGR)-Oct-1 (nt -1718 to -1710), hGR-cAMP response element (CRE; nt -1649 to -1641), hGR-GATA (nt -1602 to -1597), and hGR-activating protein-1 (nt -1518 to -1511), that are essential to the expression of this gene. Mutations of these cis-acting motifs reduced the promoter activity. The CRE and GATA motifs were subsequently shown to be placenta specific, as mutations of these motifs caused a dramatic loss in promoter activities in the placental JEG-3 cells, but not in the ovarian carcinoma OVCAR-3, monkey kidney COS-1, and human embryonic kidney 293 cells. Gel mobility assays confirmed the binding of nuclear proteins Oct-1, CRE-binding protein, GATA-2, GATA-3, c-Fos, and c-Jun from JEG-3 cells to these four elements.

Differential expression of activin/inhibin subunit and activin receptor mRNAs in normal and neoplastic ovarian surface epithelium (OSE)

Ovarian surface epithelium (OSE) is the tissue of origin for the majority of ovarian cancers. The mechanism underlying the neoplastic transformation of OSE to ovarian cancer is poorly understood. Activin, a member of the transforming growth factor-beta superfamily, has been shown to increase cell proliferation in ovarian cancer cells. The present study was carried out to investigate the expression and regulation of activin/inhibin subunits and activin receptors in normal and neoplastic OSE. Using reverse transcriptase-polymerase chain reaction and Southern blot analysis, the mRNA levels of alpha, betaA and betaB subunits and activin receptor type IIA and IIB were analyzed in normal OSE and the ovarian cancer cell line, OVCAR-3 cells. The alpha and betaA subunits were highly expressed in normal OSE when compared to OVCAR-3 cells. By contrast, betaB subunit was highly expressed in OVCAR-3 cells, when compared to normal OSE cells. Interestingly, activin receptor IIB mRNA levels were significantly higher in OVCAR-3 when compared to normal OSE cells, whereas activin receptor IIA mRNA levels were the same in both cell types. To characterize the growth modulatory role of activin during neoplastic progression, normal OSE and OVCAR-3 cells were treated with recombinant human activin A (rh-activin A). At concentrations of 1,10 and 100 ng/ml, rh-activin A stimulated the growth of OVCAR-3 cells, but not of normal OSE. Treatment with follistatin, binding protein of activin, attenuates the stimulatory effect of activin. To determine whether the growth stimulatory action of activin in the neoplastic OSE is mediated via an autocrine regulatory mechanism, OVCAR-3 cells were treated with rh-activin A in a dose- and time-dependent manner and the expression levels of activin/inhibin subunits and activin receptors were investigated. Treatments with activin increased the alpha and betaA subunit mRNA levels in a dose- and time-dependent manner. However, no difference was observed in levels of betaB subunit, or in activin receptor type IIA and IIB mRNAs following activin treatments in OVCAR-3 cells. Taken together, these results suggest that different levels of activin/inhibin and activin receptor isoforms are expressed in normal and neoplastic OSE cells. In addition, the altered expression of the activin/inhibin subunits, as well as the cell proliferative effect of activin observed in OVCAR-3 but not in normal OSE cells, indicate that activin may act as an autocrine regulator of neoplastic OSE progression.

Gonadotropin-releasing hormone activates mitogen-activated protein kinase in human ovarian and placental cells

Considering that the action of gonadotropin-releasing hormone (GnRH) may be mediated via different signaling pathways in extrapituitary tissues, in the present study we investigated the role of the human GnRH receptor (GnRHR) in activating mitogen-activated protein kinases (MAPKs), which regulate cell growth, division, and differentiation. The phosphorylation state of p44 and p42 MAPKs was examined using antibodies that distinguish phospho-p44/42 MAPK (P-MAPK, Thr(202)/Tyr(204)) from total p44/42 MAPK (T-MAPK, activated plus inactivated) in human ovarian and placental cells. Cell cultures were treated with various concentrations of a GnRH agonist, (D-Ala(6))-GnRH, for 5 min. (D-Ala(6))-GnRH stimulated a rapid activation of P-MAPK in human granulosa-luteal cells (hGLCs) and immortalized extravillous trophoblast (IEVT) cells. Interestingly, (D-Ala(6))-GnRH treatment of ovarian cancer (OVCAR-3) and placental carcinoma (JEG-3) cells induced a biphasic regulatory pattern in P-MAPK activity. In contrast, no change of T-MAPK levels was observed following addition of the GnRH agonist in the ovarian and placental cells examined. The physiological implication of MAPK activation by GnRH in the ovarian and placental cells was also investigated. Human GLCs were treated with (D-Ala(6))-GnRH for 24 h, and progesterone secretion was measured by an established RIA. (D-Ala(6))-GnRH induced a significant decrease in progesterone secretion with maximum inhibition (a 45% decrease over basal level) at 10(-7) M. This inhibitory effect was completely reversed by pretreatment with MAPK/ERK kinase 1 (MEK1) inhibitor (PD98059), suggesting the involvement of the MAPK pathway in hGLCs. Placental JEG-3 cells were treated with (D-Ala(6))-GnRH for 24 h, and betahCG mRNA level was measured using Northern blot analysis. (D-Ala(6))-GnRH stimulated the expression of betahCG mRNA to 160% of control value in JEG-3 cells. In contrast to the ovarian cells, pretreatment of JEG-3 cells with PD98059 failed to block the stimulatory effect of GnRH on betahCG mRNA level, suggesting that other signaling pathway(s) may play a more dominant role in GnRH-induced betahCG mRNA expression. To our knowledge, this is the first demonstration that (1) GnRH induces activation of the MAPK signaling pathway in normal and carcinoma cells of the human ovary and placenta, and (2) MAPK mediates the direct action of GnRH on progesterone production in hGLCs.

The expression, regulation and signal transduction pathways of the mammalian gonadotropin-releasing hormone receptor

Normal mammalian sexual maturation and reproductive functions require the integration and precise coordination of hormones at the hypothalamic, pituitary, and gonadal levels. Hypothalamic gonadotropin-releasing hormone (GnRH) is a key regulator in this system; after binding to its receptor (GnRHR), it stimulates de novo synthesis and release of gonadotropins in anterior pituitary gonadotropes. Since the isolation of the GnRHR cDNA, the expression of GnRHR mRNA has been detected not only in the pituitary, but also in extrapituitary tissues, including the ovary and placenta. It has been shown that change in GnRHR mRNA is one of the mechanisms for regulating the expression of the GnRHR. To help understand the molecular mechanism(s) involved in transcriptional regulation of the GnRHR gene, the 5' flanking region of the GnRHR gene has recently been isolated. Initial characterization studies have identified several DNA regions in the GnRHR 5' flanking region which are responsible for both basal expression and GnRH-mediated homologous regulation of this gene in pituitary cells. The mammalian GnRHR lacks a C-terminus and possesses a relatively short third intracellular loop; both features are important in desensitization of many others G-protein coupled receptors (GPCRs), Homologous desensitization of GnRHR has been shown to be regulated by various serine-threonine protein kinases including protein kinase A (PKA) and protein kinase C (PKC), as well as by G-protein coupled receptor kinases (GRKs). Furthermore, GnRHR was demonstrated to couple with multiple G proteins (Gq/11, Gs, and Gi), and to activate cascades that involved the PKC, PKA, and mitogen-activator protein kinases. These results suggest the diversity of GnRHR-G protein coupling and signal transduction systems. The identification of second form of GnRH (GnRH-II) in mammals adds to the complexity of the GnRH-GnRHR system. This review summaries our recent progress in understanding the regulation of GnRHR gene expression and the GnRHR signal transduction pathways.

Autocrine role of gonadotropin-releasing hormone and its receptor in ovarian cancer cell growth

We have recently proposed an autocrine role of gonadotropin-releasing hormone (GnRH) and its receptor (GnRH-R) in human ovarian surface epithelium. In the present study, we examine the presence and role of a GnRH/GnRH-R loop in epithelial ovarian cancer cells, OVCAR-3. A dose-dependent biphasic response in GnRH and GnRH-R mRNA levels were observed after treating with GnRH agonist [GnRHa, (D-Ala6)-GnRH], for 24 h. High concentrations of GnRHa (10(-9) M and 10(-7)) decreased the GnRH and GnRH-R mRNA levels, whereas a low concentration (10(-11) M) resulted in an upregulation of GnRH and GnRH-R genes expression. Cotretment with the competitive antagonist, antide, prevented the biphasic effect induced by GnRHa, confirming the specificity of the response. In addition, GnRHa treatment resulted in a time- and dose-dependent inhibition on OVCAR-3 cells growth. A significant inhibition of proliferation was detected as early as the d 2 of treatment. Treatment with 10(-7) M GnRHa induced DNA fragmentation in OVCAR-3 cells, suggesting that the GnRHa-induced antiproliferation in OVCAR-3 cells was mediated by apoptosis. Again, this effect was prevented by cotreatment of antide. Taken together, our findings strongly support the notion that GnRH acts as an autocrine/paracrine regulator of ovarian cancer cell proliferation.

The expression, regulation and signal transduction pathways of the mammalian gonadotropin-releasing hormone receptor

Normal mammalian sexual maturation and reproductive functions require the integration and precise coordination of hormones at the hypothalamic, pituitary, and gonadal levels. Hypothalamic gonadotropin-releasing hormone (GnRH) is a key regulator in this system; after binding to its receptor (GnRHR), it stimulates de novo synthesis and release of gonadotropins in anterior pituitary gonadotropes. Since the isolation of the GnRHR cDNA, the expression of GnRHR mRNA has been detected not only in the pituitary, but also in extrapituitary tissues, including the ovary and placenta. It has been shown that change in GnRHR mRNA is one of the mechanisms for regulating the expression of the GnRHR. To help understand the molecular mechanism(s) involved in transcriptional regulation of the GnRHR gene, the 5' flanking region of the GnRHR gene has recently been isolated. Initial characterization studies have identified several DNA regions in the GnRHR 5' flanking region which are responsible for both basal expression and GnRH-mediated homologous regulation of this gene in pituitary cells. The mammalian GnRHR lacks a C-terminus and possesses a relatively short third intracellular loop; both features are important in desensitization of many others G-protein coupled receptors (GPCRs), Homologous desensitization of GnRHR has been shown to be regulated by various serine-threonine protein kinases including protein kinase A (PKA) and protein kinase C (PKC), as well as by G-protein coupled receptor kinases (GRKs). Furthermore, GnRHR was demonstrated to couple with multiple G proteins (Gq/11, Gs, and Gi), and to activate cascades that involved the PKC, PKA, and mitogen-activator protein kinases. These results suggest the diversity of GnRHR-G protein coupling and signal transduction systems. The identification of second form of GnRH (GnRH-II) in mammals adds to the complexity of the GnRH-GnRHR system. This review summaries our recent progress in understanding the regulation of GnRHR gene expression and the GnRHR signal transduction pathways.Key words: gonadotropin-releasing hormone receptor, transcriptional regulation, desensitization, signal transduction.

Hormonal regulation of estrogen receptor alpha and beta gene expression in human granulosa-luteal cells in vitro

Estrogen is one of the major sex steroid hormones that is produced from the human ovary, and its actions are established to be a receptor-mediated process. Despite the demonstration of estrogen receptor (ER) expression, little is known regarding the regulation of ER in the human ovary. In the present study we investigated the expression and hormonal regulation of ERalpha and ERbeta in human granulosa-luteal cells (hGLCs). Using RT-PCR amplification, both ERalpha and ERbeta messenger ribonucleic acid (mRNA) were detected from hGLCs. Northern blot analysis revealed that ERalpha is expressed at a relatively lower level than ERbeta. Basal expression studies indicated that ERalpha mRNA levels remain unchanged, whereas ERbeta mRNA levels increased with time in culture in vitro, suggesting that ERbeta is likely to play a dynamic role in mediating estrogen action in hGLCs. The regulation of ERalpha and ERbeta expression by hCG was examined. hCG treatment (10 IU/mL) significantly attenuated the ERalpha (45%; P < 0.01) and ERbeta (40%; P < 0.01) mRNA levels. The hCG-induced decrease in ERalpha and ERbeta expression was mimicked by 8-bromo-cAMP (1 mmol/L) and forskolin (10 micromol/L) treatment. Additional studies using a specific protein kinase A (PKA) inhibitor (adenosine 3',5'-cyclic monophosphorothioate, Rp-isomer, triethylammonium salt) and an adenylate cyclase inhibitor (SQ 22536) further implicated the involvement of the cAMP/PKA signaling pathway in hCG action in these cells. The hCG-induced decrease in ERalpha and ERbeta mRNA levels was prevented in the presence of these inhibitors. Next, the effect of GnRH on ER expression was studied. Sixty-eight percent (P < 0.001) and 60% (P < 0.001) decreases in ERalpha and ERbeta mRNA levels, respectively, were observed after treatment with 0.1 micromol/L GnRH agonist (GnRHa). Pretreatment of the cells with a protein kinase C (PKC) inhibitor (GF109203X) completely reversed the GnRHa-induced down-regulation of ERalpha and ERbeta expression, suggesting the involvement of PKC in GnRH signal transduction in hGLCs. In agreement with the semiquantitative RT-PCR results, Western blot analysis detected a decrease in ERalpha and ERbeta proteins levels in hGLCs after treatment with hCG (10 IU/mL), GnRH (0.1 micromol/L), 8-bromo-cAMP (1 mmol/L), forskolin (10 micromol/L), or phorbol 12-myristate 13 acetate (10 micromol/L). Functionally, we demonstrated an inhibition of progesterone production in hGLCs in vitro by 17beta-estradiol, and this inhibitory effect was eliminated by pretreatment of 10 IU/mL hCG or 0.1 micromol/L GnRHa for 24 h before 17beta-estradiol administration. In summary, we observed a differential expression of ERalpha and ERbeta mRNA in hGLCs in vitro. The demonstration of hCG- and GnRHa-induced down-regulation of ERalpha and ERbeta gene expression suggests that hCG and GnRH may contribute to the control of granulosa-luteal cell function. Furthermore, our data suggest that the effects of hCG and GnRH on ERalpha and ERbeta expression in hGLCs are mediated in part by activation of PKA and PKC signaling pathways, respectively.

Transcriptional down-regulation of human gonadotropin-releasing hormone (GnRH) receptor gene by GnRH: role of protein kinase C and activating protein 1

Clinical applications of GnRH agonists (GnRHa) are based primarily on the decrease in gonadotropin release after down-regulation of the GnRH receptor (GnRHR) by continuous GnRHa administration. However, the molecular mechanisms underlying the transcriptional regulation of the human GnRHR gene after prolonged GnRH treatment remain poorly understood. In the present study GnRHa-mediated regulation of human GnRHR gene transcription was studied by transiently transfecting the mouse gonadotrope-derived (alphaT3-1) cells with a 2297-bp human GnRHR promoter-luciferase construct (p2300-LucF). A dose- and time-dependent decrease in human GnRHR promoter activity was observed after GnRHa treatment. An average 71% decrease in promoter activity was observed after 24-h treatment with 0.1 microM GnRHa, which was blocked by cotreatment of the GnRH antagonist, antide. This effect was mimicked by phorbol 12-myristate 13-acetate (TPA) administration. In addition, the GnRHa- and TPA-mediated decrease in the human GnRHR promoter activity was reversed by a specific protein kinase C (PKC) inhibitor, GF109203X, or depletion of PKC by TPA pretreatment. These findings indicate that the activation of the PKC pathway is important in regulating the human GnRHR gene expression. By progressive 5'-deletion studies, we have identified a 248-bp DNA fragment (-1018 to -771, relative to the translation start site) at the 5'-flanking region of the human GnRHR gene that is responsible for the GnRHa-mediated down-regulation of human GnRHR promoter activity. Analysis of this sequence reveals the existence of two putative activating protein-1 (AP-1) sites with 87% homology to the consensus sequence (5'-TGA(G/C)T(C/A)A-3'), located at -1000 to -994 (5'-TTAGACA-3', in complementary orientation) and -943 to 937 (5'-TGAATAA-3'). Using competitive gel mobility shift assays, AP-1 binding was observed within this 248-bp region. Site-directed mutation of the putative AP-1-binding site located at -1000 to -994 abolished the GnRHa-induced inhibition. Further competitive GMSA and supershift experiments confirmed the identity of AP-1 binding in this region. By the use of Western blot analysis, a significant increase in c-Jun (100%; P < 0.05) and c-Fos (50%; P < 0.05) protein levels was observed after GnRHa treatment in alphaT3-1 cells. In addition, our data suggested that a change in AP-1 composition, particularly c-Fos, was important in mediating GnRHa-induced inhibition of human GnRHR gene expression. We conclude that activation of the PKC pathway by GnRH is important in controlling human GnRHR gene expression. In addition, the putative AP-1-binding site located at -1000 to -994 of the human GnRHR5'-flanking region has been functionally identified to be involved in mediating this down-regulatory effect.

Regulation of human gonadotropin-releasing hormone receptor gene expression in placental cells

GnRH has been suggested to regulate hCG secretion in the placenta. In the present study, we report isolation of full-length GnRH receptor (GnRHR) complementary DNA from human placental cells, including a choriocarcinoma cell line (JEG-3), immortalized extravillous trophoblasts (IEVT), and first trimester cytotrophoblast cells in primary culture. Sequence analysis of the placental GnRHR complementary DNA revealed a 100% similarity to its pituitary counterpart. Northern blot analysis using polyadenylated RNA isolated from JEG-3 and IEVT cells revealed a 2.5- and 1.2-kb GnRHR transcripts. Using semiquantitative RT-PCR, regulation ofplacental GnRHR gene expression was examined. In contrast to pituitary gonadotrope alphaT3-1 cells, down-regulation of GnRHR messenger RNA (mRNA) levels was not observed in placental cells after 24 h of 0.1-microM GnRH agonist (GnRHa) treatment. Instead, a 43% (P < 0.01) and 30% (P < 0.05) increase in GnRHR mRNA levels was observed in JEG-3 and IEVT cells, respectively. In addition, 10 microM phorbol ester or forskolin treatments resulted in a significant increase in GnRHR expression in both JEG-3 and IEVT cells. The GnRHa-induced increase in GnRHR expression was shown to be a receptor-mediated process, as cotreatment of GnRH antagonist abolished the effect. It has also been demonstrated that these stimulatory effects on GnRHR gene expression were regulated at least in part at the transcriptional level. Pretreatment of JEG-3 cells with a specific protein kinase C inhibitor (GF109203X), adenylate cyclase inhibitor (SQ22536), or protein kinase A inhibitor [PKI-(14-22) amide, myristylated] reversed GnRHa-induced GnRHR gene expression, suggesting that the placental GnRHR couples to the protein kinase C (PKC) and cAMP/ protein kinase A (PKA) pathways. By Northern blot analysis, we observed a 100% (P < 0.001) increase in hCGbeta mRNA levels after 0.1 microM GnRHa treatment in JEG-3 cells. Again, this effect was prevented in the presence of either protein kinase C inhibitor or adenylate cyclase inhibitor, further supporting the role of the PKC and PKA pathways in GnRHR-coupled signaling in placental cells. In summary, these data strongly support the idea that 1) GnRH plays an autocrine/paracrine role in regulating placental function through a receptor-mediated mechanism; and 2) the placental GnRHR couples to both the PKC and PKA pathways.

Aspiration in chest compression alone without mechanical ventilation in the head down position in dogs

BACKGROUND

Previous work by the authors has shown that chest compressions alone without mechanical ventilation during cardiopulmonary resuscitation in the natural supine position was associated with pulmonary aspiration in dogs. The purpose of this investigation was to test the hypothesis that a head down position may prevent aspiration during chest compressions alone and whether oxygenation can be improved by simply insufflation of oral oxygen 10 min after cardiac arrest.

METHODS

Cardiac arrest was induced in ten mongrel dogs which were anesthetized and paralysed. Eight underwent chest compressions alone in different head down positions using an automatic compressor at 9 kg compression force and 3 cm compression depth. The study was composed of two parts. Part 1 evaluated the effect of insufflation of 10 l/min O2, into the mouth of the dogs, 10 min after initiation of resuscitation, using chest compressions alone. Part 2 was designed to test our hypothesis that the head down position may protect the lungs from aspiration during chest compression alone. The mouths of the dogs were filled with mixed barium and the dogs underwent serial episodes of chest compressions, for 10 min each, in the 20 degree head down, 10 degree head down and the natural supine positions. Chest X-rays with antero-posterior and lateral views were taken to evaluate pulmonary aspiration. Two additional dogs underwent direct chest compression alone in the natural supine position and the time of chest compression was shortened to 5 min.

RESULTS

All dogs in the natural position showed evidence of pulmonary aspiration of barium, five or six of the dogs showed tracheal aspiration in the 10 degree head down position, while no any barium was visualized in the tracheo-broncheal trees of the dogs in the 20 degree head down position. Supplemental oxygen in the mouth improved the mean PaO2 from 67 +/- 26 to 160 +/- 97 mmHg during chest compressions alone.

CONCLUSION

Chest compression alone without mechanical ventilation in the supine position caused pulmonary aspiration in the unprotected airway in dogs. This complication could be prevented by adopting a 20 degree head down position. The 10 degree head down position seemed to reduce the severity of the pulmonary aspiration, but not enough to eliminate the danger altogether. Supplemental oxygen in the mouth can improve oxygenation in chest compressions alone.

Regulation of gonadotropin-releasing hormone and its receptor gene expression by 17beta-estradiol in cultured human granulosa-luteal cells

There is evidence that GnRH and its binding sites are expressed in numerous extrapituitary tissues, including the primate ovary. However, the factors that regulate ovarian GnRH and its receptor (GnRH-R) remain poorly characterized. Since gonadal steroids are key regulators of ovarian functions, the present study investigated the role of 17beta-estradiol (E2) in regulating GnRH and GnRH-R messenger RNA (mRNA) from human granulosa-luteal cells (hGLCs). RT-PCR was used to isolate the ovarian GnRH-R transcript equivalent to the full-length coding region in the pituitary from hGLCs. Sequence analysis revealed that the ovarian GnRH-R mRNA is identical to its pituitary counterpart. Basal expression studies indicated that GnRH and GnRH-R mRNA levels significantly increased with time in vitro, reaching levels of 160% and 170% on day 8 and 10 of culture, respectively (P < 0.05). Treatment with various concentrations of estradiol (1-100 nM) for 24 h resulted in a dose-dependent decrease (P < 0.05) in GnRH and GnRH-R mRNA levels. Time course studies indicated that short-term treatment (6 h) with E2 (1 nM) had no significant effect on GnRH mRNA levels, while long-term treatment (48 h) with E2 resulted in a 40% decrease (P < 0.001) in GnRH mRNA levels. In contrast, GnRH-R mRNA levels exhibited a biphasic pattern, such that a short-term treatment (6 h) with E2 increased GnRH-R mRNA levels by 20% (P < 0.05), whereas long-term treatment (48 h) resulted in a 60% decrease (P < 0.001) in GnRH-R expression in hGLCs. Cotreatment of estradiol and tamoxifen blocked the E2 induced-regulation of GnRH and its receptor mRNAs, indicating that the E2 effect was mediated through its receptor. In summary, our studies demonstrate that the ovary possesses an intrinsic GnRH axis that is regulated during luteinization in vitro, and that E2 is capable of regulating GnRH and its receptor in the human ovary.

Differential expression of human gonadotropin-releasing hormone receptor gene in pituitary and ovarian cells

In terms of regulation of gene expression, gonadotropin-releasing hormone receptor (GnRHR) found in extrapituitary tissues has been suggested to be different from that in the pituitary. In the present study, we examined the molecular basis of this difference using the pituitary alphaT3-1 and ovarian carcinoma OVCAR-3 cells. As a first step, the different expression levels of GnRHR mRNA in the pituitary and ovarian cells were investigated using semi-quantitative RT-PCR. Quantitative analysis showed that the expression level of hGnRHR is a nine-fold higher in primary pituitary tissues than the primary culture of ovarian carcinomas (PCO). In pituitary alphaT3-1 cells, the expression level of hGnRHR was ten-fold higher than ovarian carcinoma OVCAR-3 cells. The possibility of the differential use of various cell-specific promoters in different cells was addressed by transiently transfecting cells with 3'-deletion clones of human GnRHR promoter. Sequential deletion of the 5'-flanking region of the gene revealed the use of two putative promoters, designated PR1 (-771 to -557) and PR2 (-1351 to -1022), and a negative control region (-1022 to -771), in the pituitary and ovarian cells. The same promoters appeared to be utilized for driving the basal promoter activities in both alphaT3-1 and OVCAR-3 cells, suggesting that there is no cell-specific promoter usage for the human GnRHR gene. Alternatively, the involvement of different regulatory protein factors was investigated using electrophoretic gel mobility shift assays. When end-labeled PR1 was used as a probe, two unique shifted complexes were identified in OVCAR-3 cells when compared to alphaT3-1 cells. One unique protein-DNA complex was observed in alphaT3-1 cells compared to OVCAR-3 cells when incubated with end-labeled PR2 as a probe. These DNA-protein complexes appeared to be specific, as they competed with excess amount of unlabelled competitor PR1 and PR2, respectively. In summary, it is unlikely that the use of a cell-specific promoter contributes to the different characteristics of ovarian GnRHR. Our study demonstrates that one mechanism by which cell-specific expression of human GnRHR is achieved is through the binding of distinct and/or combinations of cell-specific regulatory factors to various promoter elements in the 5'-flanking region of the gene.

Expression and regulation of P2U-purinergic receptor in human granulosa-luteal cells

The P2U purinoceptor (P2UR) has been identified pharmacologically in the ovary. However, the expression and regulation of the P2UR messenger RNA (mRNA) in human ovarian cells are still poorly characterized. The present study was designed to examine the expression and regulation of the P2UR in human granulosa-luteal cells (hGLCs) by RT-PCR and Northern blot analysis. A PCR product corresponding to the expected 599-bp P2UR complementary DNA was obtained from hGLCs. Molecular cloning and sequencing of the PCR product revealed an identical sequence to the reported P2UR complementary DNA. Two mRNA transcripts of 2.0 kb and 4.6 kb were identified in hGLCs using Northern blot analysis. The expression of the P2UR mRNA was down-regulated by human CG in a dose- and time-dependent manner. Treatment with 8-bromo-cAMP and forskolin also attenuated P2UR mRNA levels. Calcium signaling following the activation of the P2UR in single hGLCs was studied using microspectrofluorimetry. It revealed that, like ATP, uridine triphosphate (UTP) also induced cytosolic calcium mobilization in a dose-dependent manner. These results demonstrate for the first time that the P2UR mRNA is expressed in hGLCs and that P2UR mRNA is regulated by human CG, cAMP, and forskolin. The P2UR expressed in hGLCs functional because activation of the P2UR by ATP or UTP resulted in rapid and transient mobilization of cytosolic calcium at the single cell level. These findings further support a potential role of this neurotransmitter receptor in the human ovary.

Anesthesia for patients with aortic aneurysm for non-aneurysmal surgery--a retrospective study

BACKGROUND

Most anesthesiologists at one time or other saw the anesthetic management of patients with aortic aneurysm who underwent surgical procedures other than correction of aneurysm with or without prior knowledge of the existence of the aneurysm. The risk of intraoperate rupture of aneurysm depends on its size, type, severity, and presentation of symptoms; stress and unstable hemodynamics have been usually held responsible for the aggravation and even rupture of aneurysm. There are numerous other factors that affect the hemodynamic force during anesthesia and surgery, the increase of which would be very dangerous to the surgical patients with aortic aneurysm whether they receive anesthesia for a radical correction of the disease per se or for a surgical procedure unrelated to its correction. Therefore the anesthetic management of a patient with aortic aneurysm is a great challenge which the anesthesiologist must accept. Here, we present eleven cases of aortic aneurysm, who underwent non-corrective surgery during 1992-1998.

METHODS

There were eight cases of thoracoaortic dissecting aneurysm and three cases of abdominoaortic aneurysm. All underwent laparotomy under general anesthesia without the aneurysm being corrected. We reviewed the anesthetic management of these patients retrospectively.

RESULTS

Our review showed that no aneurysm rupture was noted in these eleven cases. Seven of the eleven patients are still alive at the time of this report.

CONCLUSIONS

We are of the opinion that under close monitoring and with prompt treatment, the allowance of a slow climb of arterial pulse pressure is acceptable and would not increase the risk of aneurysm rupture.

Role of gonadotropin-releasing hormone as an autocrine growth factor in human ovarian surface epithelium

Epithelial ovarian cancer, which accounts for 80-90% of all ovarian cancers, is the most common cause of death from gynecological malignancies and is believed to originate from the ovarian surface epithelium. In the present study we investigated the expression of GnRH and its receptor in human ovarian surface epithelial (hOSE) cells and provided novel evidence that GnRH may have antiproliferative effects in this tissue. Using RT-PCR and Southern blot analysis, we cloned the GnRH and GnRH receptor (GnRHR) in hOSE cells. Sequence analysis revealed that GnRH and its receptor have sequences identical to those found in the hypothalamus and pituitary, respectively. To address whether GnRH regulates its own and receptor messenger RNA (mRNA), the cells were treated with different concentrations of the GnRH agonist (D-Ala6)-GnRH. Expression levels of GnRH and its receptor were investigated using quantitative and competitive RT-PCR, respectively. Interestingly, a biphasic effect was observed for the GnRH and GnRHR mRNA levels. High concentrations of the GnRH agonist (10(-7) and 10(-9) M) decreased GnRH and GnRHR mRNA levels, whereas a low concentration (10(-11) M) resulted in up-regulation of GnRH and receptor mRNA levels. Treatment with the GnRH antagonist, antide, prevented the biphasic effects of the GnRH agonist in hOSE cells, confirming the specificity of the response. Furthermore, to investigate the physiological significance, we studied receptor-mediated growth regulatory effects of GnRH in human ovarian surface epithelial cells. The cells were treated with GnRH analogs, and the proliferative index of cells was measured using a [3H]thymidine incorporation assay. (D-Ala6)-GnRH had a direct inhibitory effect on the growth of hOSE cells in a time- and dose-dependent manner. This antiproliferative effect of the GnRH agonist was receptor mediated, as cotreatment of hOSE cells with antide abolished the growth inhibitory effects of the GnRH agonist. The results strongly suggest that GnRH can act as an autocrine/paracrine regulator in hOSE cells.

Expression of the messenger RNA for gonadotropin-releasing hormone and its receptor in human cancer cell lines

The presence of gonadotropin-releasing hormone (GnRH) binding sites in biopsy samples of human epithelial ovarian cancer and ovarian tumor cell lines as well as the demonstration of the inhibitory effects of GnRH analogues on the growth of these cells raised the possibility that GnRH is produced locally by ovarian cancer cells. In order to investigate an autocrine/paracrine regulatory mechanism in human carcinomas, we have studied the expression of GnRH and GnRHR mRNA in human ovarian epithelial cell lines (OVCAR-3 and SKOV-3), human choriocarcinoma cell line (JEG-3) and human hepatocarcinoma cell line (HepG 2). Using primers corresponding to published human GnRH and GnRHR cDNA sequences, predicted PCR products were obtained from these cell lines by reverse transcription-polymerase chain reaction (RT-PCR) and confirmed by Southern hybridization. Sequencing analysis of GnRH PCR products showed that their sequences have 100% identity to the published human GnRH cDNA sequence. These results indicated that GnRH and GnRHR genes are expressed in all the cell lines tested in the present study, and strengthen the concept that GnRH may act as an autocrine regulator on the growth of cancer cells.