amphotericin-b and Choriocarcinoma

The sensitivity to actinomycin-D (Act-D) and the changes in survival rate of two human choriocarcinoma cell lines (BeWo and SCH) were studied in vitro and the following results were obtained. BeWo was shown to be more sensitive to Act-D than SCH, when the survival rate was compared in the two cell lines. 3H X Act-D uptake was 39 pmol/10(6) cells in BeWo and 12 pmol/10(6) cells in SCH after a two hours treatment. Those results suggested that the sensitivity to Act-D of choriocarcinoma cells was positively correlated with the intracellular Act-D concentration. The intracellular Act-D concentration was increased depending upon the concentrations of amphotericin B (AMB). After a two hours treatment with Act-D and AMB, the intracellular Act-D concentrations were twice in BeWo, and 2.3 times in SCH comparing with those treated with Act-D alone. The synergistic effects of Act-D and AMB on the survival rate were 1,000 times in BeWo and 100 times in SCH compared with those treated with Act-D alone. From the above, combination therapy with Act-D and AMB was supposed to be one of the trial methods in the treatment of drug resistant choriocarcinoma.

Topics: Amphotericin B; Cell Line; Cell Survival; Choriocarcinoma; Colony-Forming Units Assay; Dactinomycin; Drug Evaluation, Preclinical; Drug Synergism; Humans; Male; Stomach Neoplasms; Tumor Stem Cell Assay

The cultured human choriocarcinoma JEG-3 cells secrete biologically active HCG and free HCG alpha-subunit. When compared with the alpha-subunit dissociated from HCG obtained either from pregnancy urine or JEG-3 cells, free alpha-subunit has a larger molecular weight, is more acidic and is non-functional, lacking the property to recombine with the HCG beta-subunit. The understanding of the biochemical differences observed between free alpha-subunit and alpha-subunit found in HCG is important and should help to unravel the biosynthesis of gonadotrophins. Two proteins which bind to the cell membrane, epidermal growth factor and concanavalin A, are capable of stimulating JEG-3 cell secretion. Epidermal growth factor stimulates the secretion of HCG while concanavalin A stimulates both HCG and HCG alpha-subunit secretion. Amphotericin B, an antifungal agent commonly used in tissue cultures, which also affects the cell membrane, was shown to stimulate HCG and HCG alpha-subunit secretions. The use of these agents should contribute to the understanding of membrane-related events which lead to the secretion of HCG and alpha-subunit.

Topics: Amphotericin B; Cells, Cultured; Choriocarcinoma; Chorionic Gonadotropin; Concanavalin A; Epidermal Growth Factor; Female; Humans; Pregnancy; Uterine Neoplasms