[Paclitaxel carried by long circulating microemulsions used for metabonomic chemotherapy of cancer].

Long circulating paclitaxel microemulsions (TXL-M) were prepared and its anticancer effect was evaluated in metronomic chemotherapy of cancer using animal tumor models. In TXL-M, paclitaxel was dissolved in vitamin E and polyethylene glycol-distearoylphosphatidylethanolamine (PEG-DSPE) was used as surfactant. The shape and particle size distribution of TXL-M were evaluated using an electronic microscope and a laser size scanner. The toxicity comparisons of TXL-M and paclitaxel were conducted using mice. Its anticancer effect and long circulation were evaluated using animal tumor model in C57BL/6 mice. The average diameter of TXL-M was (98.6 +/- 11.2) nm and its zeta potential was (-32.4 +/- 6.8) mV. Compared with paclitaxel, TXL-M showed lower toxicity. When used in metronomic chemotherapy of cancer, TXL-M showed longer circulation time in the blood and greater anticancer effect than paclitaxel. Thus, TXL-M is a better candidate for metronomic chemotherapy of cancer than paclitaxel injection.