Methods: Five to six week old male athymic nude mice were inoculated with 3x106 Sk-Hep-1 cells subcutaneously and then randomly divided into two groups. Group A was fed a basal mouse chow diet and Group B the basal diet supplemented with 0.5% NM. Four weeks later, the mice were euthanized and their tumors were excised, weighed and processed for histology. In addition, the effect of NM on the viability of SK-Hep-1 cells, by MTT assay, invasion through Matrigel, MMP secretion by zymography and induction of apoptosis by Live-Green Caspases kit were also determined.
Results: Dietary exposure to 0.5% NM resulted in a decrease in the incidence by 33% as well as inhibition in tumor growth by 36%. In vitro, NM inhibited cell viability by 33% over the control at 500 and 1000 µg/ml concentration and induced apoptosis in a dose-dependent manner. NM inhibited secretion of MMP-2 and MMP-9 as well as invasion through Matrigel in a dose dependent fashion, with virtual total inhibition at 1000 µg/ml.
Conclusions: The results presented demonstrate that the nutrient mixture of chemopreventive agents inhibits the growth of hepatocellular carcinoma cells both in vivo and in vitro and invasion in Matrigel.
hepatocellular carcinoma; SK-Hep-1; nutrient mixture of chemopreventive agents; athymic nude mice; apoptosis; invasion