H. Iwasawa

Effect of methotrexate on the growth and human chorionic gonadotropin secretion of human choriocarcinoma cell lines in vitro

The effect of methotrexate (MTX) on the growth and human chorionic gonadotropin (hCG) secretion of five gestational and two nongestational human choriocarcinoma cell lines was studied in vitro. A striking heterogeneity in hCG secretion was noted among the cell lines. The growth of cells which secreted large quantities of hCG, such as HCCM-5, BeWo, and IMa, was inhibited by continuous exposure to 2 X 10(-8)M MTX. In contrast, cells which secreted little hCG, such as SCH, ENAMI-1, and GCH-1, showed no response to the growth inhibitory action of 2 X 10(-8)M MTX and the 3H-thymidine uptake was not reduced by treatment with MTX at doses of up to 10(-4)M for 48 hours. The common morphologic alterations observed in the cells which responded to MTX were an increase in the number of multinucleated giant cells, the appearance of vacuoles and granules in the cytoplasm, and enlargement of the nuclei. Increased hCG secretion was observed in accordance with the appearance of such morphologically altered cells. Part of the mechanisms of resistance to MTX appeared to involve both impairment of MTX uptake by the cells and an increase in the level of intracellular dihydrofolate reductase.

Serum levels of six tumor markers in patients with benign and malignant gynecological disease

SummaryWe studied the pretreatment serum levels of 6 tumor markers in gynecological patients with and without malignant disease. The tumor markers were carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA), ferritin, Schwangerschaftsprotein 1 (SP1), Schwangerschaftsprotein 3 (SP3) and cancer antigen 125 (CA125). The results were as follows: (1) Serum CA125 and TPA levels were raised in 81% and 57% of patients with ovarian serous cystadenocarcinoma: CEA and SP3, in 52% and 43% respectively of patients with ovarian mucinous cystadenocarcinoma; CA125, TPA and SP3, in 76%, 48% and 48% respectively of patients with other ovarian malignancies; and TPA and SP3, in 56% and 40% respectively of patients with endometrial carcinoma. (2) Serum levels of TPA, ferritin and CA125 were more often raised with advancing stages of malignant disease. (3) Serum TPA levels were elevated in 55% of patients with stage I endometrial carcinoma, and serum SP3 levels were elevated in 35% of patients with a stage I malignant ovarian neoplasm and in 45% of patients with endometrial carcinoma. (4) One of the 6 tumor markers showed a raised level in 84% of patients with gynecologic malignancy as against 56% in those with benign gynecologic diseases.

A newly established human gestational choriocarcinoma cell line and its characterization

The cell biological characteristics of a newly established human gestational choriocarcinoma cell line, HM, were examined and compared with four other gestational and two nongestational choriocarcinoma cell lines. Striking heterogeneity in the production and secretion of hCG and its subunits was observed among the cell lines. The HM cell line consisted mainly of cytotrophoblast-like cells, and the hCG and its subunit values in both the cells and culture fluid were extremely low. The syncytiotrophoblast-like multinucleated giant cells which were occasionally seen in other cell lines were scarce in the HM cell line in vitro. On the other hand, deviation of the LDH isozyme pattern to the heart-type (LDH1) was characteristic of the HM cells in contrast to the other cell lines in which LDH3 was dominant. The HM cell line represents useful material for investigating the cell biological heterogeneity of human choriocarcinomas.

Establishment and properties of a human choriocarcinoma cell line of ovarian origin

SummaryA human nongestational choriocarcinoma cell line of ovarian origin (IMa) was established in vitro. This cell line had been subcultured serially more than 22 times over 18 months. Small polygonal cells with a prominent nucleus were dominant and a sparsity of cytoplasmic organelles was an ultrastructural characteristic of the IMa cells. The production and secretion of human chorionic gonadotropin and its subunits were identified by radioimmunoassay. The IMa cells were transplantable in the hamster cheek pouch and the histological diagnosis was choriocarcinoma. A newly established ovarian choriocarcinoma cell line can be considered useful for clarifying the biological differences between nongestational and gestational choriocarcinoma cells.

Comparison of the intraperitoneal and intravenous routes of cisplatin administration in an advanced ovarian cancer model of the rat

A model of human advanced ovarian cancer was made by intra-abdominal inoculation of a cloned ovarian adenocarcinoma cell line of the Sprague-Dawley rat (ROT68/C1) into isologous newborn rats. Intra-abdominal tumors and tumors metastatic to the lung developed in 100% of the animals within 3 weeks after inoculation. With use of this model the intraperitoneal and intravenous routes of cisplatin (cis-diamminedichloroplatinum) administration were compared with regard to both the pharmacokinetics and the antitumor activity. After 2 hours of administration the serum cisplatin values were greater following use of the intraperitoneal route than with use of the intravenous route. Cisplatin values in the intra-abdominal tumor tissues were greater after the intraperitoneal route of administration than the intravenous route, and the growth was suppressed more prominently after intraperitoneal administration. No difference in drug values in the kidney tissues was found between the two administration routes. Thus the intraperitoneal route of cisplatin administration seems to be much more effective against advanced ovarian cancer confined to intra-abdominal cavity than does the intravenous route.

AFP-producing sertoli-leydig cell tumor of the ovary

SummaryA tumor of the right ovary in a 21-year-old single woman is reported. Secondary amenorrhea, hirsutism, acne and deepening of the voice were associated with the tumor. Light and electron microscopic examinations showed that the tumor was composed of cells resembling Sertoli and Leydig cells of the testis in their cytology features and growth patterns. High levels of circulating dehydroepiandrosterone, androstene-dione, testosterone and alpha-fetoprotein (AFP) were found preoperatively. Preoperative estrogen and progesterone levels were all slightly above the upper limits of normal for females. These hormone and AFP levels fell to within the normal range after removal of the tumor. Direct hormone and AFP production of this tumor was confirmed by immunohistochemical techniques and long-term cell cultures in vitro. This is possibly the first report on a Sertoli-Leydig cell tumor in which AFP has been identified in the patients plasma, in part of the tumor cells and the culture fluid.

Effect of cis-dichlorodiammineplatinum(II) on cloned ovarian adenocarcinoma cells of the rat in vitro

Abstract Cloned rat ovarian adenocarcinoma cells (ROT58/C3) treated for 1 hr with 0.5 (μg/ml or more of cis -dichlorodiammineplatinum(II) (DDP) or Adriamycin (ADM) revealed a marked decrease in survival as estimated by the colony-forming method. Compared to cloned rat uterine adenocarcinoma cells (HTP/C1), the ROT58/C3 cells were more sensitive to the cytotoxic effect of both drugs. The survival of exponentially growing ROT58/C3 cells was reduced to less than 10% by a 0.5 μg/ml dose of DDP, as compared to a 1 μg/ml dose of ADM. Extensive morphological changes such as enlargement of the nuclear and nucleolar diameters, increase in the number of nucleoli, and the appearance of coarse and opaque chromatins were observed by optical and electron microscopy at as early as 48 hr after exposure to DDP for 1 hr. In addition, accumulation of cells at the G 2 phase in the cell cycle was observed by flow microfluorometry.

In vivo studies on the antitumor effect of cis-dichlorodiammineplatinum(II) against transplantable ovarian adenocarcinoma cells of the rat

Both prolongation of survival and inhibition of tumor growth were observed in rats inoculated with 5 X 10(5) cloned ovarian adenocarcinoma (ROT68/C1) cells when they were administered intraperitoneally with cis-dichlorodiammineplatinum(II) (Cisplatin) at doses of from 1 to 4 mg/kg body wt every 3 weeks or one-third of the dose every week. However, the effects were not dose-schedule dependent and administration of 2 mg/kg every 3 weeks appeared to be the most effective. In contrast to nontreated controls, rats treated with Cisplatin developed both degeneration and necrosis particularly in tumor cells located around the capillaries, and thrombus formation was detected on the inside of many capillaries. Severe nephro- and hepatotoxicities were demonstrated after four courses of Cisplatin administration at doses of 2 mg/kg or more every 3 weeks.

Effect of cytochalasin B on growth, multinucleation and human chorionic gonadotropin secretion in a human choriocarcinoma cell line

Treatment of human choriocarcinoma cells with cytochalasin B at the doses of inhibiting cell division but not inhibiting nuclear division led to in vitro formation of the multinucleated syncytiotrophoblast-like ( STL ) cells. A concomitant increase in human chorionic gonadotropin (hCG) secretion per cell was noted. Immunocytochemical staining demonstrated the predominant localization of hCG in the STL cells. These results indicate that multinucleation stimulates hCG synthesis and secretion in the choriocarcinoma cells.

Experiments with tissue cultures from a human ovarian serous cystadenocarcinoma producing cancer antigen 125 (CA125), tissue polypeptide antigen (TPA) and carcinoembryonic antigen (CEA)

SummaryThe patient was a 57-year-old woman with ovarian serous cystadenocarcinoma in FIGO clinical stage IV. Cancer antigen 125 (CA 125), tissue polypeptide antigen (TPA) and carcinoembryonic antigen (CEA) were immunohistochemically demonstrated in tumor cells, and the variations of serum CA125 and TPA levels reflected the clinical course. The tumor tissue obtained at exploratory laparotomy was minced with scissors, and transplanted subcutaneously into female nude mice for in vivo maintenance. The tumor cells from 5th generation nude mice were dispersed in Eagles minimal essential medium supplemented with 10% fetal calf serum, and incubated in Falcon tissue culture dishes at 37°C in 5% CO2 in air for in vitro maintenance. The results were as follows: Histopathologically the tumor transplanted into nude mice showed a cystadenocarcinoma, which closely resembled the original human tumor. Immunohistochemically CA125, TPA and CEA were demonstrated in the tumor transplanted into nude mice as well as in the original human tumor. From the growth curve in nude mice, the doubling time was estimated to be about 3.5 days. Serum TPA levels in nude mice were increased in proportion to the tumor growth after transplantation, but serum levels CA125 and CEA were normal. The concentrations of CA125 and TPA were increased in the conditioned media compared with the control media, although the elevated values were decreased with subsequent passages. CEA concentrations in the conditioned media were unchanged.