Eiji Imaizumi

Inhibitory effects by oral administration of ginsenoside Rh2 on the growth of human ovarian cancer cells in nude mice

Recently two new compounds, ginsenosides Rh1 and Rh2, have been isolated from an ethanol extract of the processed root ofPanax ginseng CA Meyer, and Rh2 (but not Rh1) has been found to cause growth inhibition of cultured B16 melanoma cells. We have also demonstrated that Rh2 caused inhibition of cultured human ovarian cancer cell (HRA) proliferation. The effect of oral administration of Rh2 on tumor growth and survival of nude mice bearing HRA cells was examined. Nude mice were inoculated subcutaneously in the right flank with 106 HRA cells. After 7 days of tumor inoculation 2 mg/kgcis-diamminedichloroplatinum(II) (cisplatin) was administered intraperitoneally once a week for 5 weeks. In Rh2-treated groups. Rh2 was dissolved in absolute ethanol, adjusted with distilled water to 1, 15, and 120 μM, and 0.4 ml of each concentration was administered orally by canula every day for 90 days, from the next day of tumor inoculation. The tumor volume, hematocrit and body weight were measured every week. On days 56 and 63 after tumor inoculation, the tumor volumes in all groups treated with Rh2 were significantly less than those in an ethanol-treated control group and also in cisplatin treated group. After 70 days, the tumor growth in nude mice treated with 15 μM and 120 μM Rh2 was significantly inhibited compared to that in a cisplatin treated group as well as a control group. Consequently, the survival of nude mice treated with 15 μM and 120 μM Rh2 was also significantly prolonged, compared to that of cisplatin treated mice. No toxic effects were observed in any of the mice.

Changes of peripheral blood lymphocyte subsets before and after operation of patients with endometriosis

This study was performed to elucidate whether endometriotic lesions can affect peripheral blood lymphocyte‐subsets. Changes of lymphocyte‐subsets of normal healthy women and patients with uterine myoma or endometriosis before and after operation were also examined by using two‐color assay methods. The percentage and absolute number of CD57+CD16+ cells [moderately differentiated natural killer (NK) cells] of NK cell subsets in peripheral blood from patients with endometriosis were signficantly lower than values from normal healthy women and patients with uterine myoma, while there was no difference in CD4+ and CD8+ lymphocyte‐subsets between normal healthy women and patients with uterine myoma or endometriosis. In patients with endometriosis the percentage and absolute number of CD8+CD11+ cells (suppressor T‐cells) was significantly increased after operation, while those in patients with uterine myoma did not change. On the other hand, resection of endometriotic lesions resulted in a significant decrease of the percentage of CD57+CD16+ cells (immature NK cells) and a significant increase of not only the percentage but also the absolute number of CD57+CD16+ cells (moderately differentiated NK cells), suggesting that existence of endometriotic lesions disturbs differentiation of the NK cells. Furthermore, suppressor inducer T‐cells as shown by measuring CD4+2H4+ and CD4+4B4− cells were significantly increased after operation of endometriosis. These results suggest that endometriotic lesions can affect differentiation of NK cells and such functional changes of the NK cells may be involved with progression or development of endometriosis.

Gene Expressions of Oxytocin and Oxytocin Receptor in Cumulus Cells of Human Ovary

Oxytocin (OT) has been detected in mammalian granulosa-luteal cells during the early stages. The purpose of this study was to explore gene expressions of OT and OT receptor (OTR) in human cumulus cells. Cumulus cells enclosing a mature oocyte were obtained from 6 women undergoing clinical in vitro fertilization and embryo transfer programs. OT and OTR gene expressions were investigated by employing reverse transcription polymerase chain reaction and reverse transcription polymerase chain reaction/single-strand conformation polymorphism methods. OT gene expression in the cumulus cells was positive in 5 women and weakly positive in the remaining patient. The structure of OT mRNA in the cumulus cells was equivalent to that in human hypothalamus. OTR gene expression was also observed in the cumulus cells. This study is the first to describe the simultaneous expression of both OT and OTR genes in human cumulus cells. It is suggested that local OT plays some important roles in fertility through modification of the micro-environment around the oocyte.

Effects of granulocyte-colony-stimulating factor and interleukin-2 on ascites formation and the survival time of nude mice bearing human ovarian cancer cells

Abstract The aim of this study was to elucidate the effect of intraperitoneal (i.p.) instillations of granulocyte-colony-stimulating factor (G-CSF) and/or interleukin-2 (IL-2) on ascites formation and the survival time of nude mice with malignant ascites, produced by i.p. inoculation of human ovarian cancer cells. When the nude mice were treated with medium alone, ascites was observed in all mice 28 days after tumor inoculation. When the mice were treated with cis-diamminedichloroplatinum(II) (cisplatin) alone, G-CSF alone or IL-2 alone, it took 35 days for the ascites to form in all mice. When cisplatin was combined with G-CSF or IL-2, one of ten mice did not form ascites during the observation period. Surprisingly, when G-CSF and IL-2 were simultaneously administered, ascites formation was not observed in any mice. Although i.p. treatment with cisplatin alone significantly prolonged the survival time, compared to medium alone, the lytic activity of spleen cells against HRA cells was significantly suppressed. When G-CSF or IL-2 was combined with cisplatin, the suppression by cisplatin was eliminated and subsequently resulted in a prolongation of the survival time. When G-CSF was combined with IL-2, both the peritoneal and splenic macrophages/monocytes were stimulated and the splenic lytic activity was about double that following treatment with G-CSF alone on IL-2 alone, suggesting that complete inhibition of ascites formation results not only from a significant increase of the peritoneal macrophages but also from enhancement of the lytic activity. Two mice, died from dissemination of tumor in the abdominal cavity, but eight mice survived without tumor for more than 90 days. As confirmed by monitoring body weight and hematocrit, G-CSF and IL-2 seemed to have no adverse effect. From these results, we conclude that a combination therapy with G-CSF and IL-2 might be of clinical use for inhibiting large amounts of ascites, which may inhibit therapeutic effects for ovarian cancer patients.

A Novel Biological Aspect of Ovarian Oxytocin: Oxytocin Gene Expression in Cumulus/Luteal Cells and the Effect of Oxytocin on Embryogenesis in Fertilized Oocytes

Recently, several reports have demonstrated the presence of oxytocin (OT) in the corpus luteum of mammalian species. However, the biological role of ovarian OT remains obscure. This study was performed to examine OT gene expression in cumulus cells of mice and humans, and in human corpus luteum, and the role of OT in early embryogenesis. OT gene and OT mRNA were analyzed by reverse transcription-polymerase chain reaction, with single-strand-conformation polymorphism and heteroduplex procedures. OT-treated in-vitro-fertilized mouse oocytes were cultured and the rate of blastocyst development estimated. An immunohistochemical study was also carried out to detect OT on the surface of the mouse oocytes.

Primary ovarian lymphoma. A case report.

SummaryA 44-year-old woman with stage IV non-Hodgkins lymphoma (NHL) of the left ovary is described. She had an extended hysterectomy and bilateral salpingooophorectomy and thereafter received six courses of combination chemotherapy (cyclophosphamide, adriamycin, vincristine and predonisolone; CHOP). The patient is well with no evidence of recurrence at 12 months after surgery. The literature on primary ovarian lymphoma is reviewed.

Correlation between the Stimulatory Effect of Oxytocin on the Formation of Inositol Phosphates and the Oxytocin Receptor Level in the Pregnant Rabbit Myometrium

Objective: In order to elucidate the roles of inositol trisphosphate (IP3) and oxytocin (OT) receptors in rabbit parturition, the concentration of IP3 induced by OT and the OT receptor levels were determined in rabbit myometria before and after parturition.

Changes in Plasma Cyclic AMP and Cyclic GMP during Spontaneous Labor and Labor Induced by Oxytocin, Prostaglandin F2α and Prostaglandin E2

To investigate the response of cyclic nucleotides to the oxytocic agents administered for induction of labor, plasma concentrations of cyclic AMP (cAMP) and cyclic GMP (cGMP) were determined by radioimmunoassay during spontaneous labor and labor induced by oxytocin (OT), prostaglandin F2 alpha (PGF2 alpha), or PGE2 (PGE2). Subjects were 7 Japanese women in each labor group. Plasma cAMP levels significantly rose at the time of crowning of the fetal head in all 4 groups. They did not increase until that time in the 3 labor groups (spontaneous, OT-induced, and PGF2 alpha-induced labor groups). In the PGE2-induced labor group, plasma cAMP levels were significantly higher at labor onset (mean +/- SEM = 16.5 +/- 1.3 pg/ml) when compared to the pretreatment values (13.7 +/- 1.0 pg/ml), and increased thereafter gradually toward the time of crowning of the head (26.3 +/- 2.0 pg/ml). Plasma cGMP levels in the OT-induced group significantly rose after the onset of labor and remained at a high level until expulsion of the fetus. Plasma cGMP levels in the other groups did not change significantly throughout labor. These results suggest that cAMP may be involved in the labor process induced by PGE2, and that cGMP may be in that induced by OT.