Anti-neoplastic efficacy of Haimiding on gastric carcinoma and its mechanisms

AIM:To study the anti-neoplastic effect of Haimiding and its mechanisms of action.METHODS:Experiments using MIT and colony formation were carried out to study the in vitro anti-neoplastic action of Haimiding, its in vivo anti-neoplastic action was studied by observing its effect on the weight of tumors in FC mice and S180, H22 tumor bearing mice, as well as their life spans.The effect of Haimiding on cell apoptosis and different stages of cell cycles in human gastric carcinoma cells were studied by flow cytometry. Its effect on [Ca^2+]i of human gastric carcinoma cells and the source of Ca^2+ during the change of [Ca^2+]i were observed by confocal laser scanning technique.RESULTS:Haimiding showed a definite cytotoxicity to 8 human tumor cell lines, which was most prominent against BGC-823, Eca-109 and HCT-8 tumor cells. It also exhibited an obvious inhibition on colony formation of the above tumor cell lines, which was most prominent in Eca-109 tumor cells. It showed obvious inhibition on the growth of tumor in FC mice and S180 bearing mice as well as prolonged the life span of H22 bearing mice. It was able to induce apoptosis and elevate intracellular [Ca^2+]i concentration of tumor cells.The source of Ca^2+ came from both extracellular Ca^2+ influx and intracellular Ca^2+ release.CONCLUSION:Haimiding is composed of a TCM preparation and 5-flurouracil.Its anti-neoplastic potency is highly enhanced by synergism as compared with either one of its components. Its mechanisms of anti-neoplastic action can be attributed to its action to initiate apoptosis of tumor cells by opening the membrane calcium channel and inducing intracellular Ca^2+ release to elevate [Ca^2+]i of the tumor cells.

PREPARATION AND ADSORBABILITY OF DEXTRAN MICROSPHERES WITH UNIFORM DIAMETER

The method of preparing uniform dextran microspheres with a narrow diameter distribution was introduced and the adsorbability of these microspheres was evaluated.The microspheres were prepared in W/O microemulsion using 0.5% dextran solution as the aqueous phase and n-hexane as the oil phase.Characteristics of the prepared dextran microspheres were examined with laser light blocking technique,optical microscope and ultraviolet spectrometer.The results show that the prepared dextran microspheres have uniform morphology and narrow diameter distribution,nearly 92% of them having a diameter of 56.6 μm.In vitro evaluation of adsorbability,wet dextran microspheres have good adsorption of 98.32 mg/g of model drug methylene blue in 20.86 mg/L methylene blue solution at 25℃.The adsorption of dried dextran microspheres under the same condition is 132.15 mg/g,which is even higher.And the adsorbability of dextran microspheres has significant relationship with the concentration of methylene blue and temperature.The adsorbability is better at lower temperature and higher concentration of methylene blue.