Preparation of the core-shell structure adriamycin lipiodol microemulsions and their synergistic anti-tumor effects with diethyldithiocarbamate in vivo

We prepared the core-shell structure adriamycin lipiodol microemulsions (ADM-CSLMs) and evaluated their in vivo antitumor effects in combination with Diethyldithiocarbamate (DDC). Two types of ADM-CSLMs, adriamycin liposome-lipiodol microemulsion(ADM-LLM) and adriamycin microsphere lipiodol microemulsion (ADM-MLM), were prepared through the emulsification method. The drug loading and encapsulation efficiency of ADM-CSLMs were measured by the high-performance liquid chromatograph (HPLC). The size and shape of the ADM-CSLMs were determined by an atom force microscopy (AFM), a transmission electron microscopy (TEM), and a particle size analyzer, respectively. The synergistic effects of DDC and ADM-CSLMs for cancer treatment of carcinoma drug-resistance cell was evaluated by the MTT method, the activation of superoxide dismutase (SOD) was detected by chemiluminescence, and the ADM accumulation in cells was measured by flow cytometry. Walker-256 carcinoma was transplanted to the livers of the male SD rats, ADM-CSLMs were administrated to the livers of the rats by intervention hepatic artery embolization through microsurgery. The tumor growth and animal survival were evaluated. The results show that the average diameter of ADM-LLM and ADM-MLM were 4.23 ± 1.2 μm and 4.67 ± 1.4 μm, respectively, and their ADM encapsulation efficiency were 83.7% and 87.2% with respect to loading efficiency of 82 μg/ml and 91 μg/ml. The tumor growth and animal survival in two of the ADM-CSLMs combined with DDC groups were significantly higher than that of ADM only treatment, ADM liposome combined with DDC (P< 0.01), as well as the ADM microsphere combined with DDC (P< 0.01). Therefore, ADM-CSLMs are useful carriers for the treatment of carcinoma and their anti-tumor effect can be enhanced by DDC in a suitable concentration.