Toshiyuki Sado

A randomized study of screening for ovarian cancer: a multicenter study in Japan.

Ovarian cancer is common in women from developed countries. We designed a prospective randomized controlled trial of ovarian cancer screening to establish an improved strategy for the early detection of cancers. Asymptomatic postmenopausal women were randomly assigned between 1985 and 1999 to either an intervention group (n= 41,688) or a control group (n= 40,799) in a ratio of 1:1, with follow-up of mean 9.2 years, in Shizuoka district, Japan. The original intention was to offer women in the intervention group annual screens by gynecological examination (sequential pelvic ultrasound [US] and serum CA125 test). Women with abnormal US findings and/or raised CA125 values were referred for surgical investigation by a gynecological oncologist. In December 2002, the code was broken and the Shizuoka Cohort Study of Ovarian Cancer Screening and Shizuoka Cancer Registry were searched to determine both malignant and nonmalignant diagnoses. Twenty-seven cancers were detected in the 41,688-screened women. Eight more cancers were diagnosed outside the screening program. Detection rates of ovarian cancer were 0.31 per 1000 at the prevalent screen and 0.38–0.74 per 1000 at subsequent screens; they increased with successive screening rounds. Among the 40,779 control women, 32 women developed ovarian cancer. The proportion of stage I ovarian cancer was higher in the screened group (63%) than in the control group (38%), which did not reach statistical significance (P= 0.2285). This is to our knowledge the first prospective randomized report of the ovarian cancer screening. The rise in the detection of early-stage ovarian cancer in asymptomatic postmenopausal women is not significant, but future decisions on screening policy should be informed by further follow-up from this trial.

New insights into the pathophysiology of endometriosis: from chronic inflammation to danger signal.

Background. Various theories try to explain the development and progression of endometriosis, however, no single theory can explain all aspects of this disorder. Gene expression profiling studies might reveal factors that explain variability in disease development and progression, which can serve as specific biomarkers for endometriosis and novel drug development. We have recently showed that the upregulated genes were predominantly clustered in stress and detoxification, providing a mechanistic explanation for the oxidative stress and chronic inflammatory response in endometriosis. Objective. This review aims: (1) to analyse the published data, with the aim of identifying pathways consistently regulated by the endometriosis genotype and (2) to summarise the findings of specific genes, which are involved in the process of oxidative stress and inflammation. Methods. We identified gene array and proteomics studies whose data were accessible in PubMed. Results. A major finding is the increased expressions of several markers including heat shock protein, S100, fibronectin, and neutrophil elastase, which might be involved in the process of Toll-like receptor (TLR)-dependent sterile inflammation. The study reviews a convergence in the main pathogenic process, where the TLR-mediated inflammation occurs possibly through the endogenous ligands. Conclusions. In conclusion, a circulus vitiosus of both the oxidative stress pathway and the TLR pathways is generated when the process becomes chronic (danger signal spiral).

The role of iron in the pathogenesis of endometriosis

Background. Endometriosis may cause symptoms including chronic pelvic pain and infertility, and increases susceptibility to the development of ovarian cancer. Genomic studies have started to delineate the wide array of mediators involved in the development of endometriosis. Understanding the mechanisms of endometriosis development and elucidating its pathogenesis and pathophysiology are intrinsic to prevention and the search for effective therapies. Method of study. The present article reviews the English language literature for biological, pathogenetic and pathophysiological studies on endometriosis. Several recent genomic studies are discussed in the context of endometriosis biology. Results. Severe hemolysis occurring during the development of endometriosis results in high levels of free heme and iron. These compounds oxidatively modify lipids and proteins, leading to cell and DNA damage, and subsequently fibrosis development. Recent studies based on genome-wide expression analysis technology have noted specific expression of heme/iron-dependent mediators in endometriosis. The heme/iron-dependent signaling pathway of endometriosis, which is providing new insights into the regulation of inflammation, detoxification and survival, is discussed. Conclusion. Several important endometriosis-specific genes overlap with those known to be regulated by iron. Other genes are involved in oxidative stress. Iron has a significant impact on endometriotic-cell gene expression. This review summarizes recent advances in the heme/iron-mediated signaling and its target genes, outlines the potential challenges to understanding of the pathogenesis and pathophysiology of endometriosis, and proposes a possible novel model.

Hypoxia inhibits invasion of extravillous trophoblast cells through reduction of matrix metalloproteinase (MMP)-2 activation in the early first trimester of human pregnancy.

During early pregnancy, extravillous trophoblast (EVT) cells are exposed to very low pO(2) values. In this study, we investigated the proteolytic functions and invasiveness of human primary EVT cells under hypoxic conditions to show the early placental pathophysiology. Placental samples (from 5 to 10 weeks gestation) were obtained at termination of pregnancy. Cytotrophoblast cells were separated by Percoll(®) gradient method and cultured on Matrigel(®) to obtain an invasive phenotype (similar to EVT). The invasion capacity (Matrigel-coated invasion assay), migration of the cells (wound healing assay), activity and expression of matrix metalloproteinase (MMP)-2 and tissue inhibitor for MMP (TIMP)-2 (gelatin gel zymography, ELISA, and quantitative RT-PCR), and expression of membrane-type (MT)1-MMP (western blot) were investigated. All cultures (except for quantitative RT-PCR) were performed under 20% oxygen, 5% oxygen, and 5% oxygen with 3 repetitions of 0.1% oxygen hypoxic stimulation for 1 h. Invasion and MMP2 activity of the cells were significantly increased in 20% and decreased in 0.1% oxygen. There was no significant difference in cell migration among the oxygen environments. Concentrations of MMP2 in the supernatant and expression of MT1-MMP were increased in both the 0.1% and 20% oxygen environments. The MMP2 mRNA level was increased after 1-h stimulation with 0.1% oxygen. The TIMP2 concentration was increased only in 20% oxygen, but the mRNA level was decreased in 0.1% oxygen. These results suggested that hypoxia might inhibit the invasive capacity and MMP2 activation of EVT cells in the early first trimester of pregnancy. Decrease in TIMP2 production may reduce the MMP2/TIMP2/MT1-MMP complex and lead to this unique behavior of EVT cells under hypoxic conditions.

The role of hepatocyte nuclear factor-1beta in the pathogenesis of clear cell carcinoma of the ovary.

Problem: Clear cell carcinoma (CCC) of the ovary has a number of features distinguishing it from other epithelial ovarian carcinomas (EOC) because of its characteristic histology and biology, frequent concurrence with endometriotic lesion, and highly chemoresistant nature resulting in an extremely poor prognosis. The incidence of CCC has been steadily increasing in Japan. They comprise approximately 20% of all EOC. Understanding the mechanisms of CCC development and elucidating pathogenesis and pathophysiology are intrinsic to prevention and effective therapies for CCC. Method of study: This article reviews the English language literature for biology, pathogenesis, and pathophysiological studies on endometriosis-associated EOC. Several data are discussed in the context of endometriosis and CCC biology. Results: Recent studies based on genome-wide expression analysis technology have noted specific expression of hepatocyte nuclear factor-1β (HNF-1β) in endometriosis and CCC, suggesting that early differentiation into the clear cell lineage takes place in the endometriosis. The HNF-1β-dependent pathway of CCC will be discussed, which are providing new insights into regulation of apoptosis and glycogen synthesis and resistance of CCC to anticancer agents. Conclusions: This review summarizes recent advances in the HNF-1β and its target genes; the potential challenges to the understanding of carcinogenesis, pathogenesis, and pathophysiology of CCC; and a possible novel model is proposed.

Fatal Factors of Clinical Manifestations and Laboratory Testing in Patients with Amniotic Fluid Embolism

Aims: To identify factors leading to fatality of patients with amniotic fluid embolism (AFE). Methods: Patients who had fatal or nonfatal AFE were registered at the Hamamatsu University School of Medicine in the Department of Obstetrics and Gynecology from 1992 to 2006. Data collected included information about demographics and clinical characteristics. The fatal factors among these data were identified using χ2 analysis and the Mann-Whitney test. Results: One hundred and thirty-five patients met the criteria, which included fatal (n = 65) and nonfatal AFE (n = 70). Maternal full-term gestational weeks, multiparous and noncesarean sections were the risk factors for death found in this study (p < 0.01). Sialyl Tn levels (mean ± SD) in the serum of patients with fatal AFE (69.7± 126.4 U/ml) were higher compared to those with nonfatal AFE (48.3± 161.8 U/ml; p = 0.003). Each of three items (cardiac arrest, dyspnea or loss of consciousness) was more common in fatal AFE (p < 0.01). Maternal pregnancy and labor complications were not associated with the distinction between fatal and nonfatal AFE. Conclusion: Factors associated with patients with fatal AFE were identified. These included multiparity, noncesarean section at full-term and the three symptoms mentioned above. Sialyl Tn levels could be a possible prognostic fatality factor.

Evidence for activation of Toll-like receptor and receptor for advanced glycation end products in preterm birth.

Objective. Individuals with inflammation have a myriad of pregnancy aberrations including increasing their preterm birth risk. Toll-like receptors (TLRs) and receptor for advanced glycation end products (RAGE) and their ligands were all found to play a key role in inflammation. In the present study, we reviewed TLR and RAGE expression, their ligands, and signaling in preterm birth. Research Design and Methods. A systematic search was performed in the electronic databases PubMed and ScienceDirect up to July 2010, combining the keywords “preterm birth,” “TLR”, “RAGE”, “danger signal”, “alarmin”, “genomewide,” “microarray,” and “proteomics” with specific expression profiles of genes and proteins. Results. This paper provides data on TLR and RAGE levels and critical downstream signaling events including NF-kappaB-dependent proinflammatory cytokine expression in preterm birth. About half of the genes and proteins specifically present in preterm birth have the properties of endogenous ligands “alarmin” for receptor activation. The interactions between the TLR-mediated acute inflammation and RAGE-mediated chronic inflammation have clear implications for preterm birth via the TLR and RAGE system, which may be acting collectively. Conclusions. TLR and RAGE expression and their ligands, signaling, and functional activation are increased in preterm birth and may contribute to the proinflammatory state.

Peripheral RAGE (Receptor for Advanced Glycation Endproducts)-ligands in normal pregnancy and preeclampsia: novel markers of inflammatory response

Inflammatory response in preeclampsia (PE) is a key feature in its pathophysiology. Advanced Glycation Endproducts (AGEs), receptors for AGEs (RAGE), and RAGE ligands are involved in systemic inflammation in various pathological conditions. In this study, we measured serum RAGE ligands in normal pregnancy controls and PE patients. Levels of Carboxymethyl Lysine (CML), HMGB1 and S100A12/EN-RAGE were measured in thirty-three normal pregnant women 3 times at 10-12 (1st measurement), 28 (2nd measurement), and 36 (3rd measurement) weeks during gestation for paired analysis. We also measured those in serum samples from 17 severe PE patients at admission using ELISA. Early onset (EO, <32 weeks) and late onset (LO, ≥32 weeks) PE patients were compared with the 2nd and 3rd measurements of normal controls, respectively. CML and HMGB1 did not change during normal pregnancy. However, S100A12/EN-RAGE decreased from the 1st to 2nd measurement (P<0.0001). Across all PE patients, serum CML was unaltered, while HMGB1 significantly increased compared to 2nd (P=0.0002) and 3rd (P<0.0001) measurement as well as individually compared to both EO (P=0.018) and LO groups (P=0.0001). S100A12 in all PE patients increased over 2nd (P=0.0015) and 3rd (P=0.0002) measurements, although only LO was significantly increased compared to the 3rd measurement (P=0.0005). Our data suggest that patterns of serum RAGE ligand concentration indicate different inflammatory pathways in normal pregnancy, EO-PE, and LO-PE.

Molecular Mechanisms Linking Endometriosis Under Oxidative Stress With Ovarian Tumorigenesis and Therapeutic Modalities

Inflammation plays a role in the pathogenesis of endometriosis. Endometriosis-associated ovarian carcinogenesis might be promoted through oxidative stress-induced increased genomic instability, aberrant methylation, and aberrant chromatin remodeling, as well as mutations of tumor suppressor genes. Aberrant expression of ARID1A, PIK3CA, and NF-kB genes has been recognized as the major target genes involved in oxidative stress-induced carcinogenesis. HNF-1beta appears to play a key role in anti-oxidative defense mechanisms. We discuss the pathophysiologic roles of oxidative stress as somatic mutations as well as highly specific agents that effectively modulate these targets.

Inflammatory pattern recognition receptors and their ligands: factors contributing to the pathogenesis of preeclampsia

ProblemPreeclampsia, a pregnancy-specific hypertensive syndrome, is one of the leading causes of premature births as well as fetal and maternal death. Preeclampsia lacks effective therapies because of the poor understanding of disease pathogenesis. The aim of this paper is to review molecular signaling pathways that could be responsible for the pathogenesis of preeclampsia.Method of studyThis article reviews the English-language literature for pathogenesis and pathophysiological mechanisms of preeclampsia based on genome-wide gene expression profiling and proteomic studies.ResultsWe show that the expression of the genes and proteins involved in response to stress, host-pathogen interactions, immune system, inflammation, lipid metabolism, carbohydrate metabolism, growth and tissue remodeling was increased in preeclampsia. Several significant common pathways observed in preeclampsia overlap the datasets identified in TLR (Toll-like receptor)- and RAGE (receptor for advanced glycation end products)-dependent signaling pathways. Placental oxidative stress and subsequent chronic inflammation are considered to be major contributors to the development of preeclampsia.ConclusionThis review summarizes recent advances in TLR- and RAGE-mediated signaling and the target molecules, and provides new insights into the pathogenesis of preeclampsia.