Shinya Yoshioka

Trophoblasts acquire a chemokine receptor, CCR1, as they differentiate towards invasive phenotype

At the human feto-maternal interface, trophoblasts differentiate towards extravillous trophoblasts (EVTs) and form the cell column. EVTs acquire invasive activity in the distal part of the cell column and begin to migrate into the maternal tissue. We previously reported that dipeptidyl peptidase IV (DPPIV) is expressed on EVTs in the proximal part of cell column and is involved in the inhibition of their migration. Because DPPIV has been shown to degrade several chemokines, we examined possible roles of chemokines in EVT migration. Immunohistochemistry demonstrated that C-C chemokine receptor 1 (CCR1) was hardly detected on cytotrophoblasts and syncytiotrophoblast but was expressed on EVTs in the cell column. In vitro, CCR1 protein was also present on the surface of EVTs that grew out from chorionic villous explants cultured under 20% O2. Chemokines that can bind to CCR1 (CCR1 ligands), such as regulated on activation, normal T cell expressed and secreted (RANTES) and macrophage inflammatory protein-1α (MIP-1α), were confirmed in the decidual tissues by RT-PCR and immunohistochemistry. These CCR1 ligands promoted the migration of the EVTs that were isolated from the explant cultures in vitro. These results indicate that CCR1 is expressed on trophoblasts as they differentiate to EVTs and that CCR1 ligands produced from the decidual tissue induce EVT migration. By contrast, CCR1 was scarcely expressed on EVTs that grew out from villous explants cultured in 1% O2, indicating that a relatively high oxygenic environment is needed to induce CCR1 expression. Moreover, CCR1 expression on the isolated EVTs was significantly reduced in the presence of decidua-conditioned medium. Such regulation of CCR1 by surrounding oxygenic and decidual environments supports a close correlation between EVT invasion and their expression of CCR1. This study demonstrates that trophoblasts acquire CCR1 as they differentiate to an invasive phenotype at the villus-anchoring sites and indicates a novel role for the chemokine-CCR1 system in the initial step of trophoblastic invasion towards the maternal tissue.

Oct4 expression in immature teratoma of the ovary: Relevance to histologic grade and degree of differentiation

Immature teratoma of the ovary is an uncommon tumor comprising 1% of ovarian malignancies. The amount of immature neuroepithelium in the teratoma is an important prognostic factor. Although the current grading system based on this criterion is widely accepted, the biological significance of immature neuroepithelium is poorly understood. In this study, we used immunohistochemistry to evaluate the expression of Oct4 (also known as Oct3 or POU5F1), a transcription factor expressed in primordial germ cells and embryonic stem cells, along with that of PAX6, a transcription factor contributing to neurogenesis, and CD56, a known marker for tumors of neural origin, in 18 cases of pure immature teratoma of the ovary. Oct4 was expressed in the immature neuroepithelium of all 7 grade-3 cases and 2 grade-2 cases. It was not expressed in 4 grade-2 cases and all 5 grade-1 cases. These tumor cells lacked CD30 or &agr;-fetoprotein expression, which supported the diagnosis of pure immature teratoma. PAX6 was expressed in the immature neuroepithelium of all immature teratomas, but not in Oct4-positive cells. CD56 was expressed in neural components of various maturities including PAX6-positive immature neuroepithelium, but not in Oct4-positive cells. These data suggest that the expression of these markers probably reflects the differentiation status of neural tissue in immature teratomas. The finding that Oct4 expression was exclusively detected in immature neuroepithelium of high-grade immature teratomas indicates that Oct4 might serve as a promising biomarker for the diagnosis of highly malignant cases of immature teratoma.

Eph-ephrin A system regulates murine blastocyst attachment and spreading.

Although numerous adhesion molecules are expressed on mammalian endometrial epithelial cells, there have not been any studies of a mechanism to prevent premature attachment of the embryo. In this study, we examined the possible involvement of Eph–ephrin interaction, which can induce repulsive forces. In mice, Eph A1, A2, and A4 were expressed on endometrial epithelial cells and ephrin A1–4 on blastocysts. Reverse transcriptase‐polymerase chain reaction showed that mRNA expression of ephrin A1–4 on embryos transiently decreased around the implantation period. Immunohistochemistry demonstrated that the expression of Eph A1 on endometrial epithelial cells and ephrin A1 and A3 expression on embryos decreased at implantation sites. Recombinant Eph A1 reacted with cell the surface of ephrin A‐bearing trophectoderm cells. Attachment assays using Eph A1‐coated dishes showed that blastocyst attachment was reversibly inhibited by Eph A1. These findings suggest an important role of the Eph–ephrin A system in regulating the initial embryo–maternal contact during the cross‐talk period that precedes embryo implantation. Developmental Dynamics 235:3250–3258, 2006.

3α-Hydroxysteroid Dehydrogenase Messenger RNA Transcription in the Immature Rat Ovary in Response to an Ovulatory Dose of Gonadotropin

Abstract The ovulatory process in mammals involves a substantial increase in the metabolism of steroids and eicosanoids in response to a surge in LH or to an injection of hCG into experimental animals. This study provides evidence that the ovulatory stimulus causes induction of the gene for 3α-hydroxysteroid dehydrogenase (3α-HSD), an enzyme that belongs to several oxidoreductase superfamilies that affect steroid and eicosanoid metabolism. Immature Wistar rats were primed with 10 IU eCG s.c., and 48 h later the 12-h ovulatory process was initiated by 10 IU hCG s.c. Ovarian RNA was extracted at 0, 2, 4, 8, 12, and 24 h after injecting the animals with hCG. The RNA extracts were used for reverse transcription-polymerase chain reaction (PCR) differential display to detect gene expression in the stimulated ovarian tissue. One of the PCR primer sets differentially amplified a cDNA fragment that is 52.3% homologous with a 3α-HSD gene in rat liver. Northern analyses revealed that maximum transcription was at 8 h after the animals had been treated with hCG. The Northerns also indicated that the 3α-HSD cDNA probe cross-hybridized with as many as six different bands of mRNA on the blots. In situ hybridization localized 3α-HSD mRNA in the granulosa and thecal layers of mature follicles and in newly formed corpora lutea at 24 h after the ovulatory stimulus. In conclusion, gene(s) for 3α-HSD are transcribed in ovarian follicles in response to an ovulatory dose of gonadotropin. A possible function of the oxidoreductase enzyme that is translated from the 3α-HSD mRNA may be to reduce the toxic aldehyde and ketone components of the steroids and eicosanoids that accumulate in the mammalian ovary at the time of ovulation.

New regulatory mechanisms for human extravillous trophoblast invasion

Human extravillous trophoblasts (EVT) invade maternal deciduas and reconstructed maternal spiral arteries during early placentation. However, the precise regulatory mechanisms to induce EVT invasion toward arteries and/or to protect EVT from further invasion have not been well understood. Recently, it was found that EVT that had already ceased their invasion, specifically expressed cluster of differentiation (CD9) and dipeptidyl peptidase IV (DPPIV) on their cell surface. In addition, EVT migrating to maternal spiral arteries expressed CC chemokine receptor type-1 (CCR-1), which is a chemokine receptor for regulated on activation normal T cell expressed and secreted (RANTES) and so on. CD9 is associated with integrin molecules on the cell surface and is considered to modulate integrin function. In contrast, DPPIV is a cell surface peptidase that can metabolize RANTES at extracellular sites before its accessing to the chemokine receptors. In vitro functional assay showed that CD9, DPPIV and RANTES are involved in the regulation for EVT invasion. From these findings, it can be proposed that CD9 and DPPIV, including chemokines, are new regulatory factors for human extravillous trophoblasts.

A case of Sertoli-Leydig cell tumour of the ovary with a multilocular cystic appearance on CT and MR imaging

We present a case of Sertoli-Leydig cell tumour of the ovary in a 14-year-old girl who presented with abdominal distension. Ultrasonography showed a multilocular cystic lesion filled with finely echogenic fluid. Contrast-enhanced CT demonstrated a huge multilocular cystic mass with thickened septa. At MR imaging, the capsule of the cyst was focally thickened, showing intermediate signal intensity on T2-W images. Although extensive cyst formation of Sertoli-Leydig cell tumour is rare, this tumour should be considered in the differential diagnosis of a multilocular cystic ovarian tumour in a young female.

Laminin and fibronectin concentrations of the follicular fluid correlate with granulosa cell luteinization and oocyte quality

Background and AimsProgesterone production of human cultured luteinizing granulosa cells was reported to be modified by extracellular matrix, suggesting that extracellular matrix regulates luteinization of granulosa cells after ovulation. In the present study, the relationship among laminin, fibronectin, progesterone and estradiol in follicular fluid along with oocyte quality was analyzed to estimate the physiological role of extracellular matrix in follicular luteinization and oocyte quality during ovulation.Methods and ResultsFollicular fluid was collected at oocyte pick-up from the patients undergoingin vitro fertilization treatment and intracytoplasmic sperm injection. The concentrations of laminin, fibronectin, progesterone and estradiol in the follicular fluid were measured by enzyme immunoassay and radioimmunoassay. The morphology of oocytes were also assessed during the procedure of intracytoplasmic sperm injection and was classified into normal and abnormal groups. The fibronectin concentration was higher in the normal ooplasm group than in the abnormal group, but it did not correlate with estradiol or progesterone concentration. However, laminin concentration significantly correlated with that of progesterone, but not with cytoplasm morphology of oocytes. There was no difference in estradiol or progesterone concentration between the normal and abnormal groups.ConclusionThese findings suggest that extracellular matrix plays some roles in regulating human granulosa cell luteinization and oocyte quality during ovulation.

Monoamine oxidase A is highly expressed by the human corpus luteum of pregnancy

To investigate the physiological characteristics of the corpus luteum (CL) of pregnancy, we raised a mAb, human corpus luteum (HCL)-4, against human luteal cells obtained from CL of pregnancy. The affinity-purified antigen from human CL of pregnancy or placenta using HCL-4 was a 61 kDa protein. The partial amino acid sequence of the antigenic protein was identical to that of human monoamine oxidase A (MAOA, EC1.4.3.4). MAOA has been shown to catabolize catecholamines that were reported to regulate luteal function in CL and vasoconstriction in various organs. Immunohistochemistry using HCL-4 mAb showed that MAOA was intensely expressed on large luteal cells and moderately expressed on small luteal cells in the CL of pregnancy. In the CL of menstrual cycle, MAOA was weakly detected on large luteal cells but not detected at all on small luteal cells. Western blotting analysis confirmed the high expression of MAOA in CL of pregnancy. Northern blot analysis also showed the expression of MAOA mRNA in human CL, and showed that its expression was higher in CL of pregnancy than in CL of menstrual cycle. The increased expression of MAOA in the CL of pregnancy suggests the contribution of MAOA to the function of the CL of pregnancy.

Useful technique for submucous myomectomy under direct transcervical resectoscope observation

The transcervical resectoscope (TCR) is used for resecting a submucous myoma (SMM). Safe grasping of an SMM with forceps and its complete resection under transabdominal ultrasound (TAUS) guidance is not always easy. SMMs are slippery, making them difficult to grasp. The SMM moves right to left and anterior to posterior when the surgeon tries to grasp it with placental forceps. Surgeons could use small Martin forceps (65% smaller) to grasp SMMs safely and tightly under direct TCR (transcervical resectoscope) observation. We present a case in which this operative procedure was used to remove an SMM with Figure and Video. The benefits of this procedure are enormous and could be immeasurably important to hysteroscopists and gynecologists.

Choriocarcinoma with multiple lung metastases from complete hydatidiform mole with coexistent fetus during pregnancy: Choriocarcinoma from CHMCF in pregnancy

Gestational trophoblastic neoplasm (GTN) is a serious morbidity of complete hydatidiform mole with coexistent fetus (CHMCF) and usually develops after termination of pregnancy. Here we report a case of choriocarcinoma derived from CHMCF during pregnancy. A 33‐year‐old multiparous woman with suspected CHMCF was admitted with a severe cough. Computed tomography revealed multiple lung metastases. Cesarean section and hysterectomy were performed at 31 weeks of gestation on diagnosis of high‐risk GTN from International Federation of Gynecology and Obstetrics (FIGO) scoring. A live female infant weighing 1390 g was delivered. Choriocarcinoma was diagnosed from pathological findings. The patient received multi‐agent chemotherapy and was discharged on the 40th postoperative day. In conclusion, CHMCF can result in high‐risk GTN during pregnancy. For a suspected GTN, diagnosis from FIGO scoring should determine treatment strategy. If patients with CHMCF wish to continue their pregnancy, careful follow‐up, including regular chest radiography and ultrasonography, is warranted.